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Martínez-Plaza E, López-de la Rosa A, Molina-Martín A, Piñero DP. Orthokeratology effect on the corneo scleral profile: Beyond the bull's eye. Ophthalmic Physiol Opt 2024; 44:757-768. [PMID: 38240175 DOI: 10.1111/opo.13279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 05/01/2024]
Abstract
PURPOSE To assess the impact of 3 months of orthokeratology (ortho-k) contact lenses (CLs) for myopia correction on the corneoscleral profile, as changes in scleral geometry could serve as indirect evidence of alteration in the corneal biomechanical properties. METHODS Twenty subjects (40 eyes) were recruited to wear ortho-k lenses overnight; however, after discontinuation (two CL fractures, one under-correction and two non-serious adverse events), 16 subjects (31 eyes) finished a 3-month follow-up. Corneoscleral topographies were acquired using the Eye Surface Profiler (ESP) system before and after 3 months of lens wear. Steep (SimKs) and flat (SimKf) simulated keratometry and scleral sagittal height measurements for 13-, 14- and 15-mm chord lengths were automatically calculated by the ESP software. Additionally, sagittal height and slope were calculated in polar format from 21 radii (0-10 mm from the corneal apex) at 12 angles (0-330°). Linear mixed models were fitted to determine the differences between visits. RESULTS SimKs and SimKf were increased significantly (p ≤ 0.02). The sagittal height in polar format increased significantly (p = 0.046) at a radius of 2.5 mm for 150°, 180°, 210° and 240° orientations and at a radius of 3.0 mm for 210°. Additionally, the slope in polar format significantly decreased (p ≤ 0.04) at radii ranges of 0.0-0.5, 0.5-1.0 and 1.0-1.5 mm for multiple angles and at a radii range of 5.0-5.5 mm for 90°. It also increased significantly (p ≤ 0.045) at a radii range of 1.5-2.0 mm for 30° and at radii ranges of 2.0-2.5, 2.5-3.0 and 3.0-3.5 mm for multiple angles. No significant changes were found for any parameter measured from the scleral area. CONCLUSIONS Three months of overnight ortho-k lens wear changed the central and mid-peripheral corneal geometry as expected, maintaining the peripheral cornea and the surrounding sclera stability.
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Affiliation(s)
- Elena Martínez-Plaza
- Group of Optics and Visual Perception, Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain
- University of Valladolid, Valladolid, Spain
| | - Alberto López-de la Rosa
- Department of Theoretical Physics, Atomic and Optics, University of Valladolid, Valladolid, Spain
- Instituto de Oftalmobiología Aplicada (IOBA), University of Valladolid, Valladolid, Spain
| | - Ainhoa Molina-Martín
- Group of Optics and Visual Perception, Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain
| | - David P Piñero
- Group of Optics and Visual Perception, Department of Optics, Pharmacology and Anatomy, University of Alicante, Alicante, Spain
- Department of Ophthalmology, Vithas Medimar International Hospital, Alicante, Spain
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Alluyn L, Dequeker L, Dhaese S, Consejo A, De Zaeytijd J, Leroy BP, De Backer J, Kreps EO. Anterior scleral thickness in Marfan syndrome: A quantitative analysis. Acta Ophthalmol 2024. [PMID: 38773052 DOI: 10.1111/aos.16721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Accepted: 05/11/2024] [Indexed: 05/23/2024]
Abstract
PURPOSE To investigate the anterior scleral thickness (AST) in patients with Marfan syndrome (MFS). METHODS A prospective, cross-sectional study was conducted at the Department of Ophthalmology, Ghent University Hospital, Ghent, including patients with a genetically confirmed clinical diagnosis of MFS and age-, gender- and axial length-matched controls. Subjects with known corneal, conjunctival or scleral pathology and a history of ocular surgery, including pars plana vitrectomy, recent contact lens use or high-grade astigmatism were excluded. Subjects underwent non-cycloplegic autorefraction, Scheimpflug-based corneal tomography, axial length measurement and spectral-domain optical coherence tomography (OCT). AST was manually measured at 1 mm (AST1), 2 mm (AST2) and 3 mm (AST3) from the scleral spur, temporally and nasally. RESULTS A total of 56 subjects (28 subjects in the MFS group and 28 matched subjects in the control group) were included in this study. In patients with MFS, AST was significantly reduced compared to matched controls, both overall and at every analysed measuring point in the nasal and temporal areas (p < 0.001). Central corneal thickness (CCT) and mean keratometry (Kmean) values were significantly lower in patients with MFS (p < 0.05). A positive correlation was found between nasal AST and CCT in patients with MFS. No correlation was found between AST and Kmean or between AST and axial length. In patients with MFS with ectopia lentis, compared to those without, temporal AST3 was significantly lower (p < 0.05). AST was significantly lower in patients with MFS harbouring a variant predicted to cause haploinsufficiency compared to those with a variant expected to lead to a dominant negative effect for both nasal and temporal measurements. CONCLUSION Based on anterior segment OCT measurements, AST of patients with MFS is significantly lower compared to matched controls.
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Affiliation(s)
- Lien Alluyn
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
| | - Laure Dequeker
- Department of Ophthalmology, AZ Groeninge, Kortrijk, Belgium
| | | | - Alejandra Consejo
- Aragon Institute for Engineering Research (I3A), University of Zaragoza, Zaragoza, Spain
| | - Julie De Zaeytijd
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
| | - Bart P Leroy
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
- Division of Ophthalmology & Center for Cellular & Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Julie De Backer
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
- Department of Cardiology, Ghent University Hospital, Ghent, Belgium
| | - Elke O Kreps
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
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Suzuki S, Ikeda A, Uemura T, Harada K, Takahashi R, Huang J, Tsukahara-Kawamura T, Ozaki H, Kadonosono K, Uchio E. Simulation of Changes in Tensile Strain by Airbag Impact on Eyes After Trabeculectomy by Using Finite Element Analysis. Clin Ophthalmol 2024; 18:1353-1370. [PMID: 38765458 PMCID: PMC11102099 DOI: 10.2147/opth.s459925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 04/24/2024] [Indexed: 05/22/2024] Open
Abstract
Purpose We studied the kinetic phenomenon of an airbag impact on eyes after trabeculectomy using finite element analysis (FEA), a computerized method for predicting how an object reacts to real-world physical effects and showing whether an object will break, to sequentially determine the responses at various airbag deployment velocities. Methods A human eye model was used in the simulations using the FEA program PAM-GENERISTM (Nihon ESI, Tokyo, Japan). A half-thickness incised scleral flap was created on the limbus and the strength of its adhesion to the outer sclera was set at 30%, 50%, and 100%. The airbag was set to hit the surface of the post-trabeculectomy eye at various velocities in two directions: perpendicular to the corneal center or perpendicular to the scleral flap (30° gaze-down position), at initial velocities of 20, 30, 40, 50, and 60 m/s. Results When the airbag impacted at 20 m/s or 30 m/s, the strain on the cornea and sclera did not reach the mechanical threshold and globe rupture was not observed. Scleral flap lacerations were observed at 40 m/s or more in any eye position, and scleral rupture extending posteriorly from the scleral flap edge and rupture of the scleral flap resulting from extension of the corneal laceration through limbal damage were observed. Even in the case of 100% scleral flap adhesion strength, scleral flap rupture occurred at 50 m/s impact velocity in the 30° gaze-down position, whereas in eyes with 30% or 50% scleral flap adhesion strength, scleral rupture was observed at an impact velocity of 40 m/s or more in both eye positions. Conclusion An airbag impact of ≥40 m/s might induce scleral flap rupture, indicating that current airbags may induce globe rupture in the eyes after trabeculectomy. The considerable damage caused by an airbag on the eyes of short-stature patients with glaucoma who have undergone trabeculectomy might indicate the necessity of ocular protection to avoid permanent eye damage.
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Affiliation(s)
- Shuji Suzuki
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Aya Ikeda
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Takashi Uemura
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Kazuhiro Harada
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Rie Takahashi
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Jane Huang
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
| | | | - Hiroaki Ozaki
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
| | - Kazuaki Kadonosono
- Department of Ophthalmology, Yokohama City University Medical Center, Yokohama, Japan
| | - Eiichi Uchio
- Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan
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Ji F, Islam MR, Wang B, Hua Y, Sigal IA. Lamina Cribrosa Insertions Into the Sclera Are Sparser, Narrower, and More Slanted in the Anterior Lamina. Invest Ophthalmol Vis Sci 2024; 65:35. [PMID: 38648038 PMCID: PMC11044832 DOI: 10.1167/iovs.65.4.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 04/03/2024] [Indexed: 04/25/2024] Open
Abstract
Purpose The lamina cribrosa (LC) depends on the sclera for support. The support must be provided through the LC insertions. Although a continuous insertion over the whole LC periphery is often assumed, LC insertions are actually discrete locations where LC collagenous beams meet the sclera. We hypothesized that LC insertions vary in number, size, and shape by quadrant and depth. Methods Coronal cryosections through the full LCs from six healthy monkey eyes were imaged using instant polarized light microscopy. The images were registered into a stack, on which we manually marked LC insertion outlines, nothing their position in-depth and quadrant (inferior, superior, nasal, or temporal). From the marks, we determined the insertion number, width, angle to the canal wall (90 degrees = perpendicular), and insertion ratio (fraction of LC periphery represented by insertions). Using linear mixed effect models, we determined if the insertion characteristics were associated with depth or quadrant. Results Insertions in the anterior LC were sparser, narrower, and more slanted than those in deeper LC (P values < 0.001). There were more insertions spanning a larger ratio of the canal wall in the middle LC than in the anterior and posterior (P values < 0.001). In the nasal quadrant, the insertion angles were significantly smaller (P < 0.001). Conclusions LC insertions vary substantially and significantly over the canal. The sparser, narrower, and more slanted insertions of the anterior-most LC may not provide the robust support afforded by insertions of the middle and posterior LC. These variations may contribute to the progressive deepening of the LC and regional susceptibility to glaucoma.
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Affiliation(s)
- Fengting Ji
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Mohammad R. Islam
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Mechanical Engineering, University of Texas Rio Grande Valley, Edinburg, Texas, United States
| | - Bingrui Wang
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Yi Hua
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Biomedical Engineering, University of Mississippi, University, Mississippi, United States
| | - Ian A. Sigal
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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Luo J, Zhang Y, Ai S, Shi G, Han X, Wang Y, Zhao Y, Yang H, Li Y, He X. Two-dimensional elastic distribution imaging of the sclera using acoustic radiation force optical coherence elastography. J Biophotonics 2024; 17:e202300368. [PMID: 38010344 DOI: 10.1002/jbio.202300368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/23/2023] [Accepted: 11/15/2023] [Indexed: 11/29/2023]
Abstract
The scleral elasticity is closely related with many ocular diseases, but the relevant research is still insufficient. Here, we utilized optical coherence elastography to carefully study biomechanical properties of the sclera at different positions and under different intraocular pressures. Meanwhile, elastic wave velocity and Young's modulus of each position were obtained using a phase velocity algorithm. Accordingly, the two-dimensional elasticity distribution image was achieved by mapping the Young's modulus values to the corresponding structure based on the relationship between the position and its Young's modulus. Therefore, elastic information in regions-of-interest can be read and compared directly from the scleral structure, indicating that our method may be a very useful tool to evaluate the elasticity of sclera and provide intuitive and reliable proof for diagnosis and research.
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Affiliation(s)
- Jiahui Luo
- Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province and Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang, PR China
| | - Yubao Zhang
- Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province and Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang, PR China
| | - Sizhu Ai
- Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province and Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang, PR China
| | - Gang Shi
- Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province and Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang, PR China
| | - Xiao Han
- Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province and Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang, PR China
| | - Yidi Wang
- Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province and Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang, PR China
| | - Yanzhi Zhao
- Eye Center, Second Affiliated Hospital of Nanchang University, Nanchang, PR China
| | - Hongwei Yang
- Eye Center, Second Affiliated Hospital of Nanchang University, Nanchang, PR China
| | - Yingjie Li
- Department of Ophthalmology, Nanchang First Hospital, Nanchang, PR China
| | - Xingdao He
- Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province and Jiangxi Engineering Laboratory for Optoelectronics Testing Technology, Nanchang Hangkong University, Nanchang, PR China
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Gebert M, Heimbucher J, Gsell VK, Keimer K, Dillinger AE, Tamm ER. Induced Attenuation of Scleral TGF-β Signaling in Mutant Mice Increases Susceptibility to IOP-Induced Optic Nerve Damage. Invest Ophthalmol Vis Sci 2024; 65:48. [PMID: 38294803 PMCID: PMC10839816 DOI: 10.1167/iovs.65.1.48] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 01/11/2024] [Indexed: 02/01/2024] Open
Abstract
Purpose Axonal optic nerve (ON) damage in glaucoma is characteristically associated with increased amounts of active transforming growth factor-beta 2 (TGF-β2) in the ON head. Here we investigated the functional role of scleral TGF-β signaling in glaucoma. Methods A deficiency of Tgfbr2, which encodes for TGF-β receptor type II (TGF-βRII), the essential receptor for canonical TGF-β signaling, was induced in fibroblasts (including those of the sclera) of mutant mice. To this end, 5-week-old mice were treated with tamoxifen eye drops. Experimental glaucoma was induced in 8-week-old mice using a magnetic microbead (MB) model. After 6 weeks of high intraocular pressure (IOP), the ON axons and their somata in the retina were labeled by paraphenylenediamine (PPD) and RNA-binding protein with multiple splicing (RBPMS) immunohistochemistry, respectively, and quantified. Results Tamoxifen treatment resulted in a significant decrease of TGF-βRII and its mRNA in the sclera. After 6 weeks of high IOP, reduced numbers of PPD-stained ON axons were seen in MB-injected eyes in comparison with not-injected contralateral eyes. Moreover, MB injection also led to a decrease of retinal ganglion cell (RGC) somata as seen in RBPMS-stained retinal wholemounts. Axon loss and RGC loss were significantly higher in mice with a fibroblast specific deficiency of TGF-βRII in comparison with control animals. Conclusions We conclude that the ablation of scleral TGF-β signaling increases the susceptibility to IOP-induced ON damage. Scleral TGF-β signaling in mutant mice appears to be beneficial for ON axon survival in experimentally induced glaucoma.
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Affiliation(s)
- Magdalena Gebert
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Johanna Heimbucher
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Valentina K. Gsell
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Kristof Keimer
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Andrea E. Dillinger
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Ernst R. Tamm
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
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Avetisov KS, Chizhonkova EA, Avetisov SE. [Structural and functional features of the eye in Marfan syndrome. Report 1. Changes in the fibrous tunic of the eye]. Vestn Oftalmol 2024; 140:5-10. [PMID: 38450460 DOI: 10.17116/oftalma20241400115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
Marfan syndrome (MS) is an orphan hereditary connective tissue disease associated with a mutation in the FBN1 gene, which pathological manifestations are characterized by polysystemic involvement. The fibrillin-1 protein is an integral component of the sclera and cornea of the eye, and in MS its structure is distrubed. PURPOSE This study assesses potential structural and functional changes in the cornea and sclera of a patient with MS. MATERIAL AND METHODS Two groups were formed, comparable in the axial length of the eye and age: the main group - 19 patients (38 eyes) with a verified diagnosis of MS, and the control group - 24 patients (48 eyes) with myopia of varying degrees. The results obtained from MS patients were analyzed depending on the absence or presence of ectopia lentis. In addition to measuring the basic ophthalmological parameters (refraction, axial length, visual acuity), topographic keratometry, anterior segment optical coherence tomography, and ocular response analyzer were used for structural and functional assessment of the cornea and sclera. RESULTS In MS there was a statistically significant increase in the radius of curvature and a decrease in corneal refraction in the central zone compared to the control group. There were no significant differences in central corneal thickness, but there was a significant decrease in the thickness of the sclera in the limbal zone compared to the control group. There were no statistically significant changes in corneal hysteresis and corneal resistance factor in MS. CONCLUSION This study confirmed the previously obtained data on the tendency of the optical power to reliably decrease in MS (flattening of the cornea). This symptom can be considered as a compensatory factor affecting clinical refraction, while the decrease in the thickness of the sclera - as the main reason for aaxial length elongation in MS. There were no clear patterns of dependence of the changes in the cornea and sclera analyzed in this study on the presence or absence of ectopia lentis. Changes in the lens, perhaps, should be regarded only as one of the potential components of the ocular symptom complex in MS.
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Affiliation(s)
- K S Avetisov
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
| | | | - S E Avetisov
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
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Dítě J, Netuková M, Procházková A, Poláchová M, Krivosheev K, Studený P. Scleral Grafts in Ophthalmic Surgery. A Review. Cesk Slov Oftalmol 2024; 80:1-8. [PMID: 38413226 DOI: 10.31348/2024/11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
AIM To summarize the history and current trends in the use of scleral grafts in ophthalmology. MATERIALS AND METHODS We conducted a review of the literature through the MEDLINE and Cochrane Library databases. The search terms were "sclera", "graft", and "surgery". The search resulted in 1596 articles, of which we evaluated 192 as relevant. The relevant articles were sorted chronologically and according to the method of using scleral grafts, which enabled the development of a review article. RESULTS The sclera has been routinely used in ophthalmology since the 1950s in many different indications. Some of these indications have become practically obsolete over time (for example, use in the surgical management of retinal detachment), but a large number still find application today (especially use in glaucoma or oculoplastic surgery, or as a patch for a defect in the sclera or cornea). CONCLUSION Even though allogeneic sclera is currently used less frequently in ophthalmology compared to other tissue banking products and the range of its indications has partially narrowed, it remains a useful material due to its availability and properties.
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Teeuw GJ, Vergouwen DPC, Ramdas WD, Sanchez-Brea L, Andrade De Jesus D, Rothova A, Vingerling JR, Ten Berge JC. Assessment of conjunctival, epi scleral and scleral thickness in healthy individuals using anterior segment optical coherence tomography. Acta Ophthalmol 2023. [PMID: 38140822 DOI: 10.1111/aos.16606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 11/07/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023]
Abstract
PURPOSE To determine the thickness of the conjunctiva, episclera and sclera in healthy individuals using anterior segment optical coherence tomography (AS-OCT). METHODS We prospectively included 107 healthy individuals of different age groups (18-39 years, 40-54 years, 55-69 years and ≥70 years). For each eye, AS-OCT scans of four quadrants (temporal, nasal, superior and inferior) were acquired. The thickness of the conjunctiva, episclera and sclera was measured for each scan. In addition, the axial length of both eyes was measured, and general characteristics, including smoking, allergies and contact lens use, were collected. RESULTS The mean conjunctival thickness was significantly different between the nasal and superior quadrants (87 ± 30 μm vs. 77 ± 16 μm; p < 0.001), as well as the superior and inferior quadrants (77 ± 16 μm vs. 86 ± 19 μm; p = 0.001). The mean episcleral thickness was larger in the superior (174 ± 54 μm) and inferior (141 ± 43 μm) quadrants, compared to the nasal (83 ± 38 μm) and temporal quadrants (90 ± 44 μm). The mean scleral thickness of the inferior quadrant was the largest (596 ± 64 μm), followed by the nasal (567 ± 76 μm), temporal (516 ± 67 μm) and superior (467 ± 52 μm) quadrants (all p < 0.001). The averaged scleral thickness increased 0.96 μm per age year (0.41-1.47 μm, p < 0.001). CONCLUSIONS This study provides an assessment of the thickness of scleral and adjacent superficial layers in healthy individuals determined on AS-OCT, which could enable future research into the use of AS-OCT in diseases affecting the anterior eye wall.
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Affiliation(s)
- G J Teeuw
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - D P C Vergouwen
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Department of Immunology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - W D Ramdas
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - L Sanchez-Brea
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - D Andrade De Jesus
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Department of Radiology & Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - A Rothova
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - J R Vingerling
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - J C Ten Berge
- Department of Ophthalmology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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Fukumoto S, Minamoto T. Traction suture fixation technique using a capsular tension ring fragment for severe lens displacement during cataract surgery in dogs. Vet Ophthalmol 2023. [PMID: 38018339 DOI: 10.1111/vop.13167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 09/30/2023] [Accepted: 11/09/2023] [Indexed: 11/30/2023]
Abstract
OBJECTIVES To describe the traction suture fixation technique for severely displaced lenses (≥180°) using a capsular tension ring (CTR) fragment during cataract surgery in dogs, and to retrospectively investigate its clinical outcomes. ANIMALS STUDIED Eight dogs (nine eyes). PROCEDURES The medical records of dogs with severe lens displacement (≥180°) due to cataracts that underwent traction suture fixation during cataract surgery using a CTR fragment at the Grand Animal Hospital (Hyogo, Japan) between November 2019 and September 2022 were retrospectively reviewed. The retrieved data included the signalment, type of CTR, and postoperative outcomes. RESULTS A single CTR fragment was used to fix the capsular bag to the sclera in six eyes, and two CTR fragments were used at two sites in three eyes. The lengths of the CTR fragments used were 1 one-fifth fragment, 3 one-fourth fragments, and 8 one-third fragments. Postoperative complications included uveitis (nine eyes), glaucoma (one eye), posterior iris adhesion (one eye), corneal ulcer (one eye), and intracorneal stromal hemorrhage (one eye). Vision was maintained in all dogs during the follow-up period (2 months to 2 years and 8 months) without recurrent capsular bag displacement. CONCLUSIONS This technique can correct and stabilize capsular bag displacement relatively easily through a small incision during cataract surgery in dogs with severe lens displacement. Intraocular lens implantation was also possible.
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Affiliation(s)
| | - Tomomi Minamoto
- Evergreen Vet Research & Publication, Duvall, Washington, USA
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Burguera-Giménez N, Díez-Ajenjo MA, Burguera N, Peris-Martínez C. Anterior Scleral Thickness Profile in Keratoconus. Life (Basel) 2023; 13:2223. [PMID: 38004363 PMCID: PMC10671989 DOI: 10.3390/life13112223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 10/24/2023] [Accepted: 11/07/2023] [Indexed: 11/26/2023] Open
Abstract
PURPOSE Considering that peripheral corneal thinning occurs in keratoconus (KC), the anterior scleral thickness (AST) profile was measured to compare thickness variations in healthy and KC eyes across several meridians. METHODS This cross-sectional case-control study comprised 111 eyes of 111 patients: 61 KC eyes and 50 age- and axial-length-matched healthy eyes. The AST was explored at three scleral eccentricities (1, 2, and 3 mm from the scleral spur) across four scleral zones (nasal, temporal, superior, and inferior) by using swept-source optical coherence tomography. The AST variations among eccentricities and scleral regions within and between groups were investigated. RESULTS The AST significantly varied with scleral eccentricity in healthy eyes over the temporal meridian (p = 0.009), whereas in KC eyes, this variation was observed over the nasal (p = 0.001), temporal (p = 0.029) and inferior (p = 0.006) meridians. The thinnest point in both groups was 2 mm posterior to the scleral spur (p < 0.001). The sclera was thickest over the inferior region (control 581 ± 52 μm, KC 577 ± 67 μm) and thinnest over the superior region (control 448 ± 48 μm, KC 468 ± 58 μm) in both populations (p < 0.001 for all eccentricities). The AST profiles were not significantly different between groups (p > 0.05). The inferior-superior thickness asymmetry was statistically different 2 mm posterior to the scleral spur between groups (p = 0.009), specifically with subclinical KC (p = 0.03). There is a trend where the asymmetry increases, although not significantly, with the KC degree (p > 0.05). CONCLUSIONS KC eyes presented significant thickness variations among eccentricities over the paracentral sclera. Although AST profiles did not differ between groups, the inferior-superior asymmetry differences demonstrated scleral changes over the vertical meridian in KC that need further investigation.
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Affiliation(s)
- Neus Burguera-Giménez
- Anterior Segment and Cornea and External Eye Diseases Unit, Foundation Ophthalmological Medical Hospital (FOM), Av. Pío Baroja, 12, E-46015 Valencia, Spain; (M.A.D.-A.); (C.P.-M.)
- Department of Optics and Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain
| | - María Amparo Díez-Ajenjo
- Anterior Segment and Cornea and External Eye Diseases Unit, Foundation Ophthalmological Medical Hospital (FOM), Av. Pío Baroja, 12, E-46015 Valencia, Spain; (M.A.D.-A.); (C.P.-M.)
- Department of Optics and Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain
| | - Noemí Burguera
- Q Vision, Ophthalmology Department, Vithas Virgen del Mar Hospital, Ctra. el Mami a Viator, Km.1, E-04120 Almería, Spain;
| | - Cristina Peris-Martínez
- Anterior Segment and Cornea and External Eye Diseases Unit, Foundation Ophthalmological Medical Hospital (FOM), Av. Pío Baroja, 12, E-46015 Valencia, Spain; (M.A.D.-A.); (C.P.-M.)
- Surgery Department, Ophthalmology, School of Medicine, University of Valencia, Av. Blasco Ibáñez, 15, E-46010 Valencia, Spain
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Franz-Odendaal TA. The elusive scleral cartilages: Comparative anatomy and development in teleosts and avians. Anat Rec (Hoboken) 2023. [PMID: 37943147 DOI: 10.1002/ar.25345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 10/04/2023] [Accepted: 10/16/2023] [Indexed: 11/10/2023]
Abstract
The sclera of all vertebrate eyes is comprised of connective tissue, with some organisms developing cartilage within this tissue. A review of the cartilages that have been described in the vertebrate sclera and their anatomical relationships is discussed together with their potential homology. Incorrect terminology erroneously implies similarity in location, development, morphology, and evolution, which may lead some scientists to assume all cartilages in orbit are the same elements when reading the literature. Therefore, new terminology to distinguish the different types of cartilage associated with the vertebrate eye is proposed. The scleral cartilages that are likely homologous to one another and which are situated in the sclera, should be termed scleral cartilages sensu stricto, while other cartilages in the sclera should be termed ocular cartilages. Some of the cartilages also ossify, and these bones should be distinguished from the scleral ossicles. The plasticity of the scleral tissue layer and its range of morphologies from fibrous to cartilaginous connective tissue across different vertebrate lineages are also described. This review also highlights several gaps in our understanding of the vertebrate scleral cartilages, in particular.
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Chen J, Ikeda SI, Kang L, Negishi K, Tsubota K, Kurihara T. Bisphenol A exposure triggers endoplasmic reticulum stress pathway leading to ocular axial elongation in mice. Front Med (Lausanne) 2023; 10:1255121. [PMID: 37746069 PMCID: PMC10517050 DOI: 10.3389/fmed.2023.1255121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 08/23/2023] [Indexed: 09/26/2023] Open
Abstract
Background Ocular axial elongation is one of the features of myopia progression. Endoplasmic reticulum (ER) stress-associated scleral remodeling plays an important role in ocular axial elongation. Bisphenol A (BPA) is one of the most common environmental pollutants and is known to affect various human organs through ER stress. However, whether BPA exerts an effect on scleral remodeling remains unknown. The purpose of this study was to determine the effect of BPA on the development of myopia and scleral ER stress. Methods BPA was administered by intraperitoneal injection. 4-PBA was administered as an endoplasmic reticulum stress inhibitor by eye drops. Refraction and axial length were measured by refractometer and SD-OCT system. Western blot was performed to detect the expression level of ER stress-related proteins. Results BPA-administered mice exhibit axial elongation and myopic refractive shift with endoplasmic reticulum stress in the sclera. BPA administration activated scleral PERK and ATF6 pathways, and 4-PBA eye drops attenuated ER stress response and suppressed myopia progression. Conclusion BPA controlled axial elongation during myopia development in a mouse model by inducing scleral ER stress and activation of the PERK/ATF6 pathway. 4-PBA eye drops as ER stress inhibitor suppressed BPA-induced myopia development.
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Affiliation(s)
- Junhan Chen
- Laboratory of Photobiology, Keio University School of Medicine, Tokyo, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Shin-ichi Ikeda
- Laboratory of Photobiology, Keio University School of Medicine, Tokyo, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Longdan Kang
- Laboratory of Photobiology, Keio University School of Medicine, Tokyo, Japan
- Department of Ophthalmology, The First Hospital of China Medical University, Shenyang, China
| | - Kazuno Negishi
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
- Tsubota Laboratory, Inc., Tokyo, Japan
| | - Toshihide Kurihara
- Laboratory of Photobiology, Keio University School of Medicine, Tokyo, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
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Huang L, Sun H, Liu Y, Xu L, Hu M, Yang Y, Wang N, Wu Y, Guo W. GNAQ R183Q somatic mutation contributes to aberrant arteriovenous specification in Sturge-Weber syndrome through Notch signaling. FASEB J 2023; 37:e23148. [PMID: 37606556 DOI: 10.1096/fj.202300608r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/08/2023] [Accepted: 08/04/2023] [Indexed: 08/23/2023]
Abstract
Episcleral vasculature malformation is a significant feature of Sturge-Weber syndrome (SWS) secondary glaucoma, the density and diameter of which are correlated with increased intraocular pressure. We previously reported that the GNAQ R183Q somatic mutation was located in the SWS episclera. However, the mechanism by which GNAQ R183Q leads to episcleral vascular malformation remains poorly understood. In this study, we investigated the correlation between GNAQ R183Q and episcleral vascular malformation via surgical specimens, human umbilical vein endothelial cells (HUVECs), and the HUVEC cell line EA.hy926. Our findings demonstrated a positive correlation between episcleral vessel diameter and the frequency of the GNAQ R183Q variant. Furthermore, the upregulation of genes from the Notch signaling pathway and abnormal coexpression of the arterial marker EphrinB2 and venous marker EphB4 were demonstrated in the scleral vasculature of SWS. Analysis of HUVECs overexpressing GNAQ R183Q in vitro confirmed the upregulation of Notch signaling and arterial markers. In addition, knocking down of Notch1 diminished the upregulation of arterial markers induced by GNAQ R183Q. Our findings strongly suggest that GNAQ R183Q leads to malformed episcleral vasculatures through Notch-induced aberrant arteriovenous specification. These insights into the molecular basis of episcleral vascular malformation will provide new pathways for the development of effective treatments for SWS secondary glaucoma.
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Affiliation(s)
- Lulu Huang
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Hao Sun
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yixin Liu
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Li Xu
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Menghan Hu
- Shanghai Key Laboratory of Multidimensional Information Processing, East China Normal University, Shanghai, China
| | - Yijie Yang
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Ning Wang
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yue Wu
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Wenyi Guo
- Department of Ophthalmology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
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Mehr JA, Hatami-Marbini H. Finite Deformation of Scleral Tissue under Electrical Stimulation: An Arbitrary Lagrangian-Eulerian Finite Element Method. Bioengineering (Basel) 2023; 10:920. [PMID: 37627805 PMCID: PMC10451613 DOI: 10.3390/bioengineering10080920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/28/2023] [Accepted: 07/13/2023] [Indexed: 08/27/2023] Open
Abstract
The sclera is considered as the principal load-bearing tissue within the eye. The sclera is negatively charged; thus, it exhibits mechanical response to electrical stimulation. We recently demonstrated the electroactive behavior of sclera by performing experimental measurements that captured the deformation of the tip of scleral strips subjected to electric voltage. We also numerically analyzed the electromechanical response of the tissue using a chemo-electro-mechanical model. In the pre-sent study, we extended our previous work by experimentally characterizing the deformation profile of scleral strips along their length under electrical stimulation. In addition, we improved our previous mathematical model such that it could numerically capture the large deformation of samples. For this purpose, we considered the transient variability of the fixed charge density and the coupling between mechanical and chemo-electrical phenomena. These improvements in-creased the accuracy of the computational model, resulting in a better numerical representation of experimentally measured bending angles.
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Affiliation(s)
| | - Hamed Hatami-Marbini
- Mechanical and Industrial Engineering Department, University of Illinois Chicago, Chicago, IL 60607, USA
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16
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Burgoyne CF, Wang YX, Jeoung JW, Hong S, Gardiner S, Reynaud J, Fortune B, Girard MJA, Sharpe G, Nicolela M, Chauhan BC, Yang H. OCT Optic Nerve Head Morphology in Myopia II: Peri-Neural Canal Scleral Bowing and Choroidal Thickness in High Myopia-An American Ophthalmological Society Thesis. Am J Ophthalmol 2023; 252:225-252. [PMID: 36906092 PMCID: PMC10492898 DOI: 10.1016/j.ajo.2023.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/16/2023] [Accepted: 03/01/2023] [Indexed: 03/12/2023]
Abstract
PURPOSE To use optical coherence tomography (OCT) to characterize optic nerve head (ONH) peri-neural canal (pNC) scleral bowing (pNC-SB) and pNC choroidal thickness (pNC-CT) in 69 highly myopic and 138 healthy, age-matched, control eyes. DESIGN Cross-sectional, case control study. METHODS Within ONH radial B-scans, Bruch membrane (BM), BM opening (BMO), anterior scleral canal opening (ASCO), and pNC scleral surface were segmented. BMO and ASCO planes and centroids were determined. pNC-SB was characterized within 30° foveal-BMO (FoBMO) sectors by 2 parameters: pNC-SB-scleral slope (pNC-SB-SS), measured within 3 pNC segments (0-300, 300-700, and 700-1000 μm from the ASCO centroid); and pNC-SB-ASCO depth relative to a pNC scleral reference plane (pNC-SB-ASCOD). pNC-CT was calculated as the minimum distance between the scleral surface and BM at 3 pNC locations (300, 700, and 1100 μm from the ASCO). RESULTS pNC-SB increased and pNC-CT decreased with axial length (P < .0133; P < .0001) and age (P < .0211; P < .0004) among all study eyes. pNC-SB was increased (P < .001) and pNC-CT was decreased (P < .0279) in the highly myopic compared to control eyes, and these differences were greatest in the inferior quadrant sectors (P < .0002). Sectoral pNC-SB was not related to sectoral pNC-CT in control eyes, but was inversely related to sectoral pNC-CT (P < .0001) in the highly myopic eyes. CONCLUSIONS Our data suggest that pNC-SB is increased and pNC-CT is decreased in highly myopic eyes and that these phenomena are greatest in the inferior sectors. They support the hypothesis that sectors of maximum pNC-SB may predict sectors of greatest susceptibility to aging and glaucoma in future longitudinal studies of highly myopic eyes. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.
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Affiliation(s)
- Claude F Burgoyne
- From the Devers Eye Institute Optic Nerve Head Research Laboratory (C.F., J.R., H.Y.), Legacy Research Institute, Portland, Oregon, USA; Devers Eye Institute Discoveries in Sight Research Laboratories (C.F.B., S.G., J.R., B.F., H.Y.), Legacy Research Institute, Portland, Oregon, USA.
| | - Ya Xing Wang
- Beijing Institute of Ophthalmology (Y.X.W.), Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing, China
| | - Jin Wook Jeoung
- Department of Ophthalmology (J.W.J.), Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | | | - Stuart Gardiner
- Devers Eye Institute Discoveries in Sight Research Laboratories (C.F.B., S.G., J.R., B.F., H.Y.), Legacy Research Institute, Portland, Oregon, USA
| | - Juan Reynaud
- Devers Eye Institute Discoveries in Sight Research Laboratories (C.F.B., S.G., J.R., B.F., H.Y.), Legacy Research Institute, Portland, Oregon, USA
| | - Brad Fortune
- Devers Eye Institute Discoveries in Sight Research Laboratories (C.F.B., S.G., J.R., B.F., H.Y.), Legacy Research Institute, Portland, Oregon, USA
| | - Michaël J A Girard
- Ophthalmic Engineering & Innovation Laboratory (M.J.A.G.), Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Glen Sharpe
- Department of Ophthalmology and Visual Sciences (G.S., M.N., B.C.C.), Dalhousie University, Halifax, Nova Scotia, Canada
| | - Marcelo Nicolela
- Department of Ophthalmology and Visual Sciences (G.S., M.N., B.C.C.), Dalhousie University, Halifax, Nova Scotia, Canada
| | - Balwantray C Chauhan
- Department of Ophthalmology and Visual Sciences (G.S., M.N., B.C.C.), Dalhousie University, Halifax, Nova Scotia, Canada
| | - Hongli Yang
- Devers Eye Institute Discoveries in Sight Research Laboratories (C.F.B., S.G., J.R., B.F., H.Y.), Legacy Research Institute, Portland, Oregon, USA
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Makarem A, Abass A, Bao F, Elsheikh A. Assessment of age-related change of the ocular support system. Front Bioeng Biotechnol 2023; 11:1146828. [PMID: 37492801 PMCID: PMC10363727 DOI: 10.3389/fbioe.2023.1146828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 06/23/2023] [Indexed: 07/27/2023] Open
Abstract
To estimate the material stiffness of the orbital soft tissue in human orbits using an inverse numerical analysis approach, which could be used in future studies to understand the behaviour under dynamic, non-contact tonometry or simulate various ophthalmological conditions. Clinical data were obtained for the left eye of 185 Chinese participants subjected to a complete ophthalmic examination, including tests by the Corvis ST and Pentacam. 185 numerical models of the eye globes were built with idealised geometry of the sclera while considering the corneal tomography measured by the Pentacam. The models were extended to include representations of the orbital soft tissue (OST), which were given idealised geometry. The movement of the whole eye in response to an air-puff directed at the central cornea was examined and used in an inverse analysis process to estimate the biomechanical stiffness parameters of the OST. The results indicated a weak correlation of E t with the progression of age, regardless of the stress at which E t was calculated. However, there was evidence of significant differences in E t between some of the age groups. There was statistical evidence of significant differences between E t in the age range 20< years < 43 relative to E t in OST with age ranges 43< years < 63 (p = 0.022) and 63< years < 91 (p = 0.011). In contrast, E t in OST with age ranges 43< years < 63 and 63< years < 91 were not significantly different (p = 0.863). The optimised mechanical properties of the OST were found to be almost four times stiffer than properties of fatty tissue of previous experimental work. This study consolidated previous findings of the role of extraocular muscles on the ocular suppor system. In addition, the rotation of the globe during corvis loading is suggested to be of posterior components of the globe and shall be further investigated.
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Affiliation(s)
- Ahmed Makarem
- School of Engineering, University of Liverpool, Liverpool, United Kingdom
| | - Ahmed Abass
- School of Engineering, University of Liverpool, Liverpool, United Kingdom
- Faculty of Engineering, Port Said University, Port Fouad, Egypt
| | - Fangjun Bao
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ahmed Elsheikh
- School of Engineering, University of Liverpool, Liverpool, United Kingdom
- Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, China
- National Institute for Health Research (NIHR), Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust, UCL Institute of Ophthalmology, London, United Kingdom
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Jan NJ, Lee PY, Wallace J, Iasella M, Gogola A, Wang B, Sigal IA. Stretch-Induced Uncrimping of Equatorial Sclera Collagen Bundles. J Biomech Eng 2023; 145:054503. [PMID: 36459150 PMCID: PMC9791674 DOI: 10.1115/1.4056354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/20/2022] [Accepted: 11/21/2022] [Indexed: 12/03/2022]
Abstract
Stretch-induced collagen uncrimping underlies the nonlinear mechanical behavior of the sclera according to what is often called the process of recruitment. We recently reported experimental measurements of sclera collagen crimp and pressure-induced uncrimping. Our studies, however, were cross-sectional, providing statistical descriptions of crimp with no information on the effects of stretch on specific collagen bundles. Data on bundle-specific uncrimping is necessary to better understand the effects of macroscale input on the collagen microscale and tissue failure. Our goal in this project was to measure bundle-specific stretch-induced collagen uncrimping of sclera. Three goat eyes were cryosectioned sagittally (30 μm). Samples of equatorial sclera were isolated, mounted to a custom uni-axial stretcher and imaged with polarized light microscopy at various levels of clamp-to-clamp stretch until failure. At each stretch level, local strain was measured using image tracking techniques. The level of collagen crimping was determined from the bundle waviness, defined as the circular standard deviation of fiber orientation along a bundle. Eye-specific recruitment curves were then computed using eye-specific waviness at maximum stretch before sample failure to define fibers as recruited. Nonlinear mixed effect models were used to determine the associations of waviness to local strain and recruitment to clamp-to-clamp stretch. Waviness decreased exponentially with local strain (p < 0.001), whereas bundle recruitment followed a sigmoidal curve with clamp-to-clamp stretch (p < 0.001). Individual bundle responses to stretch varied substantially, but recruitment curves were similar across sections and eyes. In conclusion, uni-axial stretch caused measurable bundle-specific uncrimping, with the sigmoidal recruitment pattern characteristic of fiber-reinforced soft tissues.
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Affiliation(s)
- Ning-Jiun Jan
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213
| | - Po-Yi Lee
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213
| | - Jacob Wallace
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213
| | - Michael Iasella
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213
| | - Alexandra Gogola
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Bingrui Wang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Ian A. Sigal
- Department of Ophthalmology, Laboratory of Ocular Biomechanics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213; Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15213
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Brown DM, Yu J, Kumar P, Paulus QM, Kowalski MA, Patel JM, Kane MA, Ethier CR, Pardue MT. Exogenous All-Trans Retinoic Acid Induces Myopia and Alters Scleral Biomechanics in Mice. Invest Ophthalmol Vis Sci 2023; 64:22. [PMID: 37219510 PMCID: PMC10210516 DOI: 10.1167/iovs.64.5.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 04/21/2023] [Indexed: 05/24/2023] Open
Abstract
Purpose Ocular all-trans retinoic acid (atRA) levels are influenced by visual cues, and exogenous atRA has been shown to increase eye size in chickens and guinea pigs. However, it is not clear whether atRA induces myopic axial elongation via scleral changes. Here, we test the hypothesis that exogenous atRA will induce myopia and alter scleral biomechanics in the mouse. Methods Male C57BL/6J mice were trained to voluntarily ingest atRA + vehicle (1% atRA in sugar, 25 mg/kg) (RA: n = 16 animals) or vehicle only (Ctrl: n = 14 animals). Refractive error (RE) and ocular biometry were measured at baseline and after 1 and 2 weeks of daily atRA treatment. Eyes were used in ex vivo assays to measure scleral biomechanics (unconfined compression: n = 18), total scleral sulfated glycosaminoglycan (sGAG) content (dimethylmethylene blue: n = 23), and specific sGAGs (immunohistochemistry: n = 18). Results Exogenous atRA caused myopic RE and larger vitreous chamber depth (VCD) to develop by 1 week (RE: -3.7 ± 2.2 diopters [D], P < 0.001; VCD: +20.7 ± 15.1 µm, P < 0.001), becoming more severe by 2 weeks (RE: -5.7 ± 2.2 D, P < 0.001; VCD: +32.3 ± 25.8 µm, P < 0.001). The anterior eye biometry was unaffected. While scleral sGAG content was not measurably affected, scleral biomechanics were significantly altered (tensile stiffness: -30% ± 19.5%, P < 0.001; permeability: +60% ± 95.3%, P < 0.001). Conclusions In mice, atRA treatment results in an axial myopia phenotype. Eyes developed myopic RE and larger VCD without the anterior eye being affected. The decrease in stiffness and increase in permeability of the sclera are consistent with the form-deprivation myopia phenotype.
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Affiliation(s)
- Dillon M. Brown
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
| | - Jianshi Yu
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland, United States
| | - Praveen Kumar
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland, United States
| | - Quinn M. Paulus
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
| | - Michael A. Kowalski
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, Georgia, United States
| | - Jay M. Patel
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
- Department of Orthopaedics, Emory University School of Medicine, Atlanta, Georgia, United States
| | - Maureen A. Kane
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland, United States
| | - C. Ross Ethier
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States
| | - Machelle T. Pardue
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States
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Liang Y, Ikeda SI, Chen J, Zhang Y, Negishi K, Tsubota K, Kurihara T. Myopia Is Suppressed by Digested Lactoferrin or Holo-Lactoferrin Administration. Int J Mol Sci 2023; 24:ijms24065815. [PMID: 36982888 PMCID: PMC10057310 DOI: 10.3390/ijms24065815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/16/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
Myopia is becoming a leading cause of vision impairment. An effective intervention is needed. Lactoferrin (LF) is a protein that has been reported to inhibit myopia progression when taken orally. This study looked at the effects of different forms of LF, such as native LF and digested LF, on myopia in mice. Mice were given different forms of LF from 3 weeks of age, and myopia was induced with minus lenses from 4 weeks of age. Results showed that mice given digested LF or holo-LF had a less elongated axial length and thinned choroid, compared to those given native-LF. Gene expression analysis also showed that the groups given native-LF and its derivatives had lower levels of certain cytokines and growth factors associated with myopia. These results suggest that myopia can be more effectively suppressed by digested LF or holo-LF than native-LF.
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Affiliation(s)
- Yifan Liang
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Shin-Ichi Ikeda
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Junhan Chen
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Yan Zhang
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Kazuno Negishi
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
- Tsubota Laboratory, Inc., 34 Shinanomachi, Shinjuku-ku, Tokyo 160-0016, Japan
| | - Toshihide Kurihara
- Laboratory of Photobiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
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21
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Kose F, Orhan I, Alan A, Cabir A, Beyaz F, Duzler A. A new perspective on the corneo- scleral junction with three types of microscopy techniques. Microsc Res Tech 2023; 86:629-635. [PMID: 36929228 DOI: 10.1002/jemt.24314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 03/03/2023] [Indexed: 03/18/2023]
Abstract
The conjunctions of the cornea and sclera in the eyes of donkeys, cattle, dogs, sheep, pigs and rabbits, regardless of gender, were examined in this study. No animals were specifically sacrificed for this investigation. Scanning electron microscopy, light microscopy, and dissecting microscopy were used in this research. In the limbus of all the animals investigated, the cornea and sclera fused in accordance with a pattern. At the corneo-scleral junction, the sclera was situated anteriorly and the cornea posteriorly in the dorsal and ventral sections of the bulbus oculi. In the medial and lateral parts of the eyeball, the cornea and sclera were facing each other and interlaced. Pigmentation and the sulcus scleralis externus could be used to identify the macro-and micro-anatomical boundaries of the limbus. In addition, the cytoplasm of basal epithelial cells shrank, signaling the end of the corneal epithelium and the start of the conjunctival epithelium. The presence of Bowman's membrane in cattle and sheep eyes was definitely determined in histological examinations. Bowman's membrane in these animals came to an end at the limbus, which is where the conjunctival epithelium starts and the corneal epithelium ends. In all areas of the cornea, Bowman's membrane revealed irregular, abrupt thickening and thinning. The corneal epithelium was thick in the vertex and thinner towards the limbus, whereas Descemet's membrane was thin in the center (vertex) and thick in the periphery (near the limbus). In this study, pictures and diagrams were used to illustrate the general anatomical, histological, and morphometric characteristics of the limbus in the species under investigation. The data from our study showed that the limbus region of the bulbus oculi was narrow in the lateral and medial parts and wide in the dorsal and ventral parts. This was confirmed in the studied animals as a general rule. The width value will undoubtedly affect the number of cells covered by the regions. It is conceivable that these cells will play a significant role in the decision of where to perform surgical procedures in order to promote wound healing, giving doctors an advantage. In this circumstances, we think that the limbus should be studied in terms of clinical methods because it has different shapes depending on the species and the position of the bulbus.
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Affiliation(s)
- Fatma Kose
- Department of Veterinary Anatomy, Institute of Health Sciences, Erciyes University, Kayseri, Turkey
| | - Imdat Orhan
- Erciyes Üniversitesi Teknoloji Geliştirme Bölgesi (TEKNOPARK), Kayseri, Turkey
| | - Aydın Alan
- Faculty of Veterinary Medicine, Department of Anatomy, Erciyes University, Kayseri, Turkey
| | - Ahmet Cabir
- Department of Veterinary Histology and Embryology, Institute of Health Sciences, Erciyes University, Kayseri, Turkey
| | - Feyzullah Beyaz
- Faculty of Veterinary Medicine, Department of Histology and Embryology, Erciyes University, Kayseri, Turkey
| | - Ayhan Duzler
- Faculty of Veterinary Medicine, Department of Anatomy, Erciyes University, Kayseri, Turkey
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22
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Jiao S, Reinach PS, Huang C, Yu L, Zhuang H, Ran H, Zhao F, Srinivasalu N, Qu J, Zhou X. Calcipotriol Attenuates Form Deprivation Myopia Through a Signaling Pathway Parallel to TGF-β2-Induced Increases in Collagen Expression. Invest Ophthalmol Vis Sci 2023; 64:2. [PMID: 36723926 PMCID: PMC9904334 DOI: 10.1167/iovs.64.2.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Purpose To determine the role of calcipotriol, a vitamin D3 analogue, in myopia development and altering the expression of scleral α1 chain of type I collagen (Col1α1) in mice. We also aimed to identify if the signaling pathway mediating the above changes is different from the one involved in transforming growth factor β2 (TGF-β2)-mediated increases of COL1A1 in cultured human scleral fibroblasts (HSFs). Methods C57BL/6J mice were either intraperitoneally injected with calcipotriol and subjected to form deprivation (FD) or exposed to normal refractive development for 4 weeks. Scleral vitamin D receptor (Vdr) expression was knocked down using a Sub-Tenon's capsule injection of an adeno-associated virus-packaged short hairpin RNA (AAV8-shRNA). Refraction and biometric measurements evaluated myopia development. A combination of knockdown and induction strategies determined the relative contributions of the vitamin D3 and the TGF-β2 signaling pathways in modulating COL1A1 expression in HSFs. Results Calcipotriol injections suppressed FD-induced myopia (FDM), but it had no significant effect on normal refractive development. AAV8-shRNA injection reduced Vdr mRNA expression by 42% and shifted the refraction toward myopia (-3.15 ± 0.99D, means ± SEM) in normal eyes. In HSFs, VDR knockdown reduced calcipotriol-induced rises in COL1A1 expression, but it did not alter TGF-β2-induced increases in COL1A1 expression. Additionally, TGF-β2 augmented calcipotriol-induced rises in COL1A1 expression. TGF-β receptor (TGFBRI/II) knockdown blunted TGF-β2-induced increases in COL1A1 expression, whereas calcipotriol-induced increases in VDR and COL1A1 expression levels were unaltered. Conclusions Scleral vitamin D3 inhibits myopia development in mice, potentially by activating a VDR-dependent signaling pathway and increasing scleral COL1A1 expression levels.
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Affiliation(s)
- Shiming Jiao
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Peter Sol Reinach
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Chengjie Huang
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Lan Yu
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Huiman Zhuang
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Hongli Ran
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Fei Zhao
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,Research Unit of Myopia Basic Research and Clinical Prevention and Control, Chinese Academy of Medical Sciences, Wenzhou, Zhejiang, China,Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou, Zhejiang, China,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, China
| | - Nethrajeith Srinivasalu
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jia Qu
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou, Zhejiang, China,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, China
| | - Xiangtian Zhou
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China,Research Unit of Myopia Basic Research and Clinical Prevention and Control, Chinese Academy of Medical Sciences, Wenzhou, Zhejiang, China,Oujiang Laboratory, Zhejiang Lab for Regenerative Medicine, Vision and Brain Health, Wenzhou, Zhejiang, China,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, China
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23
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AlAmry M, Alahareef E, Aljebreen A, AlJudaibi R. Preoperative and Intraoperative Spontaneous Scleral Rupture: A Case Report and Review of Literature. Middle East Afr J Ophthalmol 2023; 30:59-61. [PMID: 38435109 PMCID: PMC10903711 DOI: 10.4103/meajo.meajo_71_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 12/05/2023] [Accepted: 12/20/2023] [Indexed: 03/05/2024] Open
Abstract
Scleral rupture is a rare but significant complication that can occur due to multiple risk factors. In this report, we discuss two instances of scleral perforation that happened during a silicone oil injection and after a peribulbar injection. Our study suggests that prior ocular surgery is a further risk factor for intraoperative scleral rupture, and more investigation is required to identify additional relevant risk factors that weaken the sclera.
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Affiliation(s)
- Mohammed AlAmry
- Emergency Department Senior Consultant, Anterior Segment Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Esraa Alahareef
- General Practitioner, Ministry of Health, Medina, Saudi Arabia
| | | | - Ramzi AlJudaibi
- Ophthalmology Consultant, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
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24
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Brown DM, Kowalski MA, Paulus QM, Yu J, Kumar P, Kane MA, Patel JM, Ethier CR, Pardue MT. Altered Structure and Function of Murine Sclera in Form-Deprivation Myopia. Invest Ophthalmol Vis Sci 2022; 63:13. [PMID: 36512347 PMCID: PMC9753793 DOI: 10.1167/iovs.63.13.13] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 11/15/2022] [Indexed: 12/15/2022] Open
Abstract
Purpose The sclera is believed to biomechanically influence eye size, facilitating the excessive axial elongation that occurs during myopigenesis. Here, we test the hypothesis that the sclera will be remodeled and exhibit altered biomechanics in the mouse model of form-deprivation (FD) myopia, accompanied by altered retinoid concentrations, a potential signaling molecule involved in the process. Methods Male C57 Bl/6J mice were subjected to unilateral FD (n = 44 eyes), leaving the contralateral eye untreated (contra; n = 44). Refractive error and ocular biometry were measured in vivo prior to and after 1 or 3 weeks of FD. Ex vivo measurements were made of scleral biomechanical properties (unconfined compression: n = 24), scleral sulfated glycosaminoglycan (sGAG) content (dimethylmethylene blue: n = 18, and immunohistochemistry: n = 22), and ocular all-trans retinoic acid (atRA) concentrations (retina and RPE + choroid + sclera, n = 24). Age-matched naïve controls were included for some outcomes (n = 32 eyes). Results Significant myopia developed after 1 (-2.4 ± 1.1 diopters [D], P < 0.001) and 3 weeks of FD (-4.1 ± 0.7 D, P = 0.025; mean ± standard deviation). Scleral tensile stiffness and permeability were significantly altered during myopigenesis (stiffness = -31.4 ± 12.7%, P < 0.001, and permeability = 224.4 ± 205.5%, P < 0.001). Total scleral sGAG content was not measurably altered; however, immunohistochemistry indicated a sustained decrease in chondroitin-4-sulfate and a slower decline in dermatan sulfate. The atRA increased in the retinas of eyes form-deprived for 1 week. Conclusions We report that biomechanics and GAG content of the mouse sclera are altered during myopigenesis. All scleral outcomes generally follow the trends found in other species and support a retina-to-sclera signaling cascade underlying mouse myopigenesis.
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Affiliation(s)
- Dillon M. Brown
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
| | - Michael A. Kowalski
- Department of Orthopedics, Emory University School of Medicine, Atlanta, Georgia, United States
| | - Quinn M. Paulus
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
| | - Jianshi Yu
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland, United States
| | - Praveen Kumar
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland, United States
| | - Maureen A. Kane
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland, United States
| | - Jay M. Patel
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
- Department of Orthopedics, Emory University School of Medicine, Atlanta, Georgia, United States
| | - C. Ross Ethier
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
| | - Machelle T. Pardue
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Healthcare System, Atlanta, Georgia, United States
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25
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Silver FH, Deshmukh T, Benedetto D, Gonzalez-Mercedes M, Mesica A. Measurement of the Elastic Modulus of Cornea, Sclera and Limbus: The Importance of the Corneal-Limbus-Scleral Biomechanical Unit. Front Biosci (Schol Ed) 2022; 14:30. [PMID: 36575840 DOI: 10.31083/j.fbs1404030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/22/2022] [Accepted: 09/29/2022] [Indexed: 11/06/2022]
Abstract
BACKGROUND Energy storage, transmission and dissipation are important considerations of normal mechanical homeostasis. In this paper we present a new technique termed vibrational optical coherence tomography (VOCT) to study the anterior anatomic structures of the pig eye to better understand how energy applied to the cornea is dissipated without delamination occurring. METHODS VOCT uses infrared light and an applied sinusoidal audible sound wave to image and measure the resonant frequency and modulus of individual macromolecular components of tissue non-invasively. We have measured the resonant frequencies and calculated the moduli of tissues in the anterior portion of the pig eye using VOCT. RESULTS While both pig and human eyes have similar resonant frequencies, they do differ in the peak amplitudes near the frequencies of 80, 120, 150 and 250 Hz. It is known that the stroma of pig cornea is much thicker than that of human corneas and these differences may explain the normalized peak height differences. The similarity of the resonant frequency peaks near 80, 120, 150 and 250 Hz of cornea, sclera and limbus suggest that the anatomically described layers in these tissues are connected into a single biomechanical unit that can store external mechanical energy and then transmit it for dissipation. Since the energy stored and dissipated is proportional to the modulus and the ability of the tissue to deform under stress, energy storage in these tissues is related to the stiffness. CONCLUSIONS It is concluded that stored energy is transmitted to the posterior segment of the eye for dissipation through the attachment with the sclera. This mechanism of energy dissipation may protect the cornea from changes in shape, curvature, and refractive power. However, ultimately, energy dissipation through thinning of the sclera may cause globe elongation observed in subjects with myopia and glaucoma.
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Affiliation(s)
- Frederick H Silver
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.,OptoVibronex, LLC., Ben Franklin Tech Partners, Bethlehem, PA 18015, USA
| | - Tanmay Deshmukh
- OptoVibronex, LLC., Ben Franklin Tech Partners, Bethlehem, PA 18015, USA
| | | | | | - Arielle Mesica
- OptoVibronex, LLC., Ben Franklin Tech Partners, Bethlehem, PA 18015, USA
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26
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Abstract
Eye gaze is an important source of information for animals, implicated in communication, cooperation, hunting and antipredator behaviour. Gaze perception and its cognitive underpinnings are much studied in primates, but the specific features that are used to estimate gaze can be difficult to isolate behaviourally. We photographed 13 laboratory-housed tufted capuchin monkeys (Sapajus [Cebus] apella) to quantify chromatic and achromatic contrasts between their iris, pupil, sclera and skin. We used colour vision models to quantify the degree to which capuchin eye gaze is discriminable to capuchins, their predators and their prey. We found that capuchins, regardless of their colour vision phenotype, as well as their predators, were capable of effectively discriminating capuchin gaze across ecologically relevant distances. Their prey, in contrast, were not capable of discriminating capuchin gaze, even under relatively ideal conditions. These results suggest that specific features of primate eyes can influence gaze perception, both within and across species.
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Affiliation(s)
- Will Whitham
- Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, USA,Department of Comparative Medicine, UT MD Anderson Cancer Center, Bastrop, TX, USA
| | - Steven J. Schapiro
- Department of Comparative Medicine, UT MD Anderson Cancer Center, Bastrop, TX, USA
| | - Jolyon Troscianko
- Centre for Ecology and Conservation, University of Exeter, Exeter, UK
| | - Jessica L. Yorzinski
- Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, USA
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27
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Ertaş TD, Kahvecioğlu KO, Erdoğan S. Morphological Aspects and Microscopic Analyses of Fibrous Tunic and Uveal Components in Bovine Eye. Microsc Microanal 2022; 28:1-14. [PMID: 35616072 DOI: 10.1017/s1431927622000812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This study aimed to reveal the anatomical features of the bovine eye by scanning electron and light microscopic methods. For this purpose, a total of 40 eyes were evaluated. Gross and microscopic characteristics of the cornea, sclera, ciliary body, choroid, iris, and lens were determined. Bowman's and Descemet's membranes of the cornea were quite dense and prominent. Collagen lamellae of the cornea were wavy in the periphery and more parallel to the basal and metachromatic fibroblasts were noted. Three to four ciliary plicae merged to form ciliary processes. The presence of prominent intermediate bands connecting the ciliary plicae was determined. The zonular fibrils merged and attached to the lens in the form of thick zonular bands. A dense corpora nigra was present at the rectangular pupillary border of the iris. Tapetum fibrosum, consisting of polygonal tapetal cells, was in blue-yellow-green color and covered most of the choroid. A complex drainage system consisting of trabecular meshwork, angular aqueous plexus, ciliary sinus, and scleral venous vessels localized in a fairly wide iridocorneal angle was identified. Identifying structural features of the bovine eye is very important and useful for pathological evaluations, understanding species-specific physiological mechanisms and for operative interventions of ruminant species.
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Affiliation(s)
- Tuba Damla Ertaş
- Department of Anatomy, Faculty of Veterinary Medicine, Tekirdağ Namık Kemal University, Tekirdağ, Turkey
| | - Kifayet Oya Kahvecioğlu
- Department of Anatomy, Faculty of Veterinary Medicine, İstanbul-Cerrrahpaşa University, İstanbul, Turkey
| | - Serkan Erdoğan
- Department of Anatomy, Faculty of Veterinary Medicine, Tekirdağ Namık Kemal University, Tekirdağ, Turkey
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28
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Gerberich BG, Hannon BG, Brown DM, Read AT, Ritch MD, Schrader Echeverri E, Nichols L, Potnis C, Sridhar S, Toothman MG, Schwaner SA, Winger EJ, Huang H, Gershon GS, Feola AJ, Pardue MT, Prausnitz MR, Ethier CR. Evaluation of Spatially Targeted Scleral Stiffening on Neuroprotection in a Rat Model of Glaucoma. Transl Vis Sci Technol 2022; 11:7. [PMID: 35536721 PMCID: PMC9100482 DOI: 10.1167/tvst.11.5.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 03/14/2022] [Indexed: 11/25/2022] Open
Abstract
Purpose Scleral stiffening may protect against glaucomatous retinal ganglion cell (RGC) loss or dysfunction associated with ocular hypertension. Here, we assess the potential neuroprotective effects of two treatments designed to stiffen either the entire posterior sclera or only the sclera adjacent to the peripapillary sclera in an experimental model of glaucoma. Methods Rat sclerae were stiffened in vivo using either genipin (crosslinking the entire posterior sclera) or a regionally selective photosensitizer, methylene blue (stiffening only the juxtaperipapillary region surrounding the optic nerve). Ocular hypertension was induced using magnetic microbeads delivered to the anterior chamber. Morphological and functional outcomes, including optic nerve axon count and appearance, retinal thickness measured by optical coherence tomography, optomotor response, and electroretinography traces, were assessed. Results Both local (juxtaperipapillary) and global (whole posterior) scleral stiffening treatments were successful at increasing scleral stiffness, but neither provided demonstrable neuroprotection in hypertensive eyes as assessed by RGC axon counts and appearance, optomotor response, or electroretinography. There was a weak indication that scleral crosslinking protected against retinal thinning as assessed by optical coherence tomography. Conclusions Scleral stiffening was not demonstrated to be neuroprotective in ocular hypertensive rats. We hypothesize that the absence of benefit may in part be due to RGC loss associated with the scleral stiffening agents themselves (mild in the case of genipin, and moderate in the case of methylene blue), negating any potential benefit of scleral stiffening. Translational Relevance The development of scleral stiffening as a neuroprotective treatment will require the identification of better tolerated stiffening protocols and further preclinical testing.
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Affiliation(s)
- Brandon G. Gerberich
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Bailey G. Hannon
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Dillon M. Brown
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - A. Thomas Read
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Matthew D. Ritch
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Elisa Schrader Echeverri
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Lauren Nichols
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Cahil Potnis
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veteran Affairs Healthcare System, Atlanta, GA, USA
| | - Sreesh Sridhar
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Maya G. Toothman
- College of Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Stephen A. Schwaner
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- Exponent, Inc., Biomechanics Practice, Atlanta, GA, USA
| | - Erin J. Winger
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Hannah Huang
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Gabby S. Gershon
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Andrew J. Feola
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veteran Affairs Healthcare System, Atlanta, GA, USA
| | - Machelle T. Pardue
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veteran Affairs Healthcare System, Atlanta, GA, USA
| | - Mark R. Prausnitz
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - C. Ross Ethier
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
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Golovchenko AV, Baum OI, Bolshunov AV, Siplivy VI. [Methods of studying deformation properties of ocular structures]. Vestn Oftalmol 2022; 138:114-119. [PMID: 35488570 DOI: 10.17116/oftalma2022138021114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Studying ocular biomechanics presents apparent interest because of certain clinical situations when in vivo evaluation of mechanical properties can help with both diagnosis and treatment. This literature review considers the approaches to studying deformation properties of various ocular structures: dynamometric methods, elastotonometry, ophthalmic mechanography, photoelasticity method, ultrasound methods, analysis of pneumatic applanation of the cornea, atomic force microscopy, holographic interferometry, optical coherence elastography. Knowledge of the particularities of tissue deformation during examination with various methods can expand our understanding of the mechanisms of pathological changes in different structures of the organ of vision, which can help develop new methods of diagnosis and treatment.
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Affiliation(s)
- A V Golovchenko
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - O I Baum
- Federal research center «Crystallography and Photonics», Moscow, Russia
| | | | - V I Siplivy
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.,Research Institute of eye diseases, Moscow, Russia
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30
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Acar YB, Yılmaz HN, Özbilen EÖ. Does Maxillary Protraction with Alt-RAMEC Protocol Affect Inferior Sclera Exposure? A Controlled 3dMD Study. Turk J Orthod 2022; 35:1-6. [PMID: 35370127 PMCID: PMC9128539 DOI: 10.5152/turkjorthod.2020.0167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 09/23/2021] [Indexed: 09/06/2023]
Abstract
OBJECTIVE The purpose of this controlled retrospective study was to measure and evaluate the inferior sclera exposure changes using 3dMD stereophotogrammetric images in a prepubertal Class III patient sample that underwent maxillary protraction with alternate rapid maxillary expansions and constrictions protocol followed by facemask. METHODS The study group included 15 prepubertal patients (mean age: 9.85 ± 1.44 years) with Class III malocclusion due to maxillary retrognathism. Nine weeks of alternate rapid maxillary expansions and constrictions protocol was followed prior to 7 months of face mask treatment and 3 months of retention with Bionator. Pretreatment (T0) and post-retention (T1) lateral cephalometric radiographs and 3dMD images were retrieved from clinical archive. The same records were used for a control group of 15 well-matched, untreated patients (mean age: 9.4 ± 0.79 years). The distance between the upper eyelid margin and the lower eyelid margin was recorded as the overall eye height (E), and the distance between inferior limbus and the lower eyelid margin was recorded as inferior sclera exposure (S). The S : E ratio in percentage was calculated. Sella-nasion-A point angle (SNA) was used as the skeletal variable. RESULTS SNA angle, right S : E, and left S : E changed significantly in both groups at T1-T0. The intergroup comparison was highly significant for SNA angle but was not significant for right and left S : E variables. CONCLUSION The S : E ratio decreased significantly in both alternate rapid maxillary expansions and constrictions/facemask and the control groups. However, the change in S : E ratio between groups was not significant.
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Affiliation(s)
- Yasemin Bahar Acar
- Department of Orthodontics, Marmara University, Faculty of Dentistry, İstanbul, Turkey
| | - Hanife Nuray Yılmaz
- Department of Orthodontics, Marmara University, Faculty of Dentistry, İstanbul, Turkey
| | - Elvan Önem Özbilen
- Department of Orthodontics, Marmara University, Faculty of Dentistry, İstanbul, Turkey
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31
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Šulavíková Z, Káčerik M, Šustykevičová Z, Krásnik V. IDIOPATHIC SCLEROCHOROIDAL CALCIFICATIONS. A CASE REPORT. Cesk Slov Oftalmol 2022; 78:86-92. [PMID: 35477249 DOI: 10.31348/2022/12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
AIM Sclerochoroidal calcifications (SCHC) are an uncommon benign ocular condition that occurs in elderly patients. SCHC usually manifest as multiple placoid yellow lesions in the midperipheral fundus, most often in the upper temporal quadrant. They are asymptomatic and often discovered during routine eye examinations in a patient with good visual acuity and visual field. According to the etiology, SCHC are divided into idiopathic, metastatic and dystrophic. CASE REPORTS This is case report of 2 patients with idiopathic SCHC, who underwent basic eye examinations, fundus photography, optical coherence tomography, ultrasonography, fluorescein angiography, fundusautofluorescence, laboratory screening and in the second case also CT head scan. CONCLUSION The aim of this publication is to point out the typical features of SCHC and their distinction from more serious conditions that they may resemble.
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32
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Svetozarskiy SN, Andreev AN. [Capabilities of optical coherence tomography in examination of senile scleral plaques]. Vestn Oftalmol 2022; 138:31-34. [PMID: 35801877 DOI: 10.17116/oftalma202213803131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
UNLABELLED Senile scleral plaque (SSP) is a degenerative disease of the sclera manifested by the appearance of gray spots with clearly defined borders anteriorly from the insertion site of horizontal rectus muscles. Even with minimal changes over time changes over time are minor, SSP weakens the structural function of the sclera and creates a risk of a complicated course associated with scleromalacia. Interest in the study of SSP is increasing due to the growing number of transscleral intravitreal injections. PURPOSE To assess the morphological characteristics of SSP using spectral optical coherence tomography (OCT). MATERIAL AND METHODS The study examined 13 patients (21 eyes) with average age of 77.1±6.3 years. OCT scanning was performed to determine OCT signs of SSP, the length (parallel to the limb), the width and height of the SSP, as well as the depth and thickness of the overlying sclera. RESULTS A combination of nasal and temporal SSP was observed in 14 eyes, and nasal only SSP was detected in 6 eyes. In all cases, OCT presented a characteristic picture of SSP observed as an intrascleral cavity with hyperreflective content with lower reflectivity than the surrounding tissues, and clear borders represented by unchanged scleral fibers. The length of the SSP parallel to the limb was 3296±820 µm, the width - 2312±436 µm, the height of the SSP cavity - 482±89 µm. The depth of SSP site was 213±36 µm, the thickness of the overlying sclera - 125±29 µm. CONCLUSION Updated information about SSP structure can be used in the development of standard surgical algorithms contributing to prevention of postoperative complications.
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Affiliation(s)
- S N Svetozarskiy
- Privolzhsky Research Medical University, Nizhny Novgorod, Russia
- Volga District Medical Centre of the Federal Medical-Biological Agency, Nizhny Novgorod, Russia
| | - A N Andreev
- Volga District Medical Centre of the Federal Medical-Biological Agency, Nizhny Novgorod, Russia
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33
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Ganjei AY, Shlager GGL, Brocks D. Scleral Tonometry Precision During Scleral Lens Wear: A Pilot Study. Clin Optom (Auckl) 2021; 13:341-350. [PMID: 35002349 PMCID: PMC8725838 DOI: 10.2147/opto.s339411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
PURPOSE To evaluate the reproducibility, and therefore the utility, of using traditional tonometry devices for measuring intraocular pressure (IOP), while a prosthetic replacement of the ocular surface ecosystem device (PD) or scleral lens is applied to the eye. PATIENTS AND METHODS Twenty subjects (40 eyes) with keratoconus were enrolled. With PD applied, the first 10 consecutive patients had IOP measured multiple times with a handheld tonometer (Tono-Pen AVIA, Reichert, Depew, NY) on the superotemporal sclera 1 mm posterior to the PD edge. This identical procedure was repeated for the next 10 consecutive patients with a pneumatonometer (Model 30, Reichert, Depew, NY). Once three reliable measurements, as defined by the study protocol, were obtained for an eye, the procedure was repeated with the same tonometer device on the fellow eye. RESULTS The mean standard deviation for reliable IOP measurements was ±2.92 mmHg, median (IQR) of 2.62 (1.68 to 3.53) mmHg in the handheld tonometer group and ±1.98 mmHg in the pneumatonometer group. There was no statistically significant difference between the groups (p = 0.07). The mean IOP range for the reliable IOP measurements was 5.5 ± 3.80 mmHg, median (IQR) of 5 (3 to 7) mmHg for the handheld tonometer group and 3.71 ±1.12 mmHg in the pneumatonometer group. There was no statistically significant difference between the groups (p = 0.06). CONCLUSION Handheld tonometry and pneumatonometry have poor reproducibility when used to measure scleral IOP in keratoconus patients, while a PD is applied to the eye. An alternative research model and methodology should be investigated and confirmed to have precision prior to proceeding with further analysis of any relationship between scleral lens wear and IOP.
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Affiliation(s)
- Allen Y Ganjei
- Department of Medical Education, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Gabriel G L Shlager
- Department of Medical Education, Tufts University School of Medicine, Boston, MA, USA
| | - Daniel Brocks
- Department of Ophthalmology, BostonSight, Needham, MA, USA
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Khomchik OV, Yusef NY, Gamidov AA, Gavrilina PD. [Technique for laser activation of scleral hydropermeability in the treatment of patients with refractory forms of glaucoma]. Vestn Oftalmol 2021; 137:82-86. [PMID: 34965072 DOI: 10.17116/oftalma202113706182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Laser cyclodestructive interventions are considered the method of choice in the treatment of refractory glaucoma. However, the traumatic nature of cyclocoagulation makes it necessary to search for more gentle methods of laser treatment. One of the possible directions is the development of laser transscleral technologies that mainly affect the uveoscleral outflow. This article presents a new technique for laser activation of scleral hydropermeability (LASH) using pulse-periodic erbium glass (Er-glass) fiber-optics laser with wave length of 1.56 μm. The article describes the parameters of laser emission and the technique of LASH, and presents the mechanism of reducing intraocular pressure associated with increased transcleral drainage of intraocular fluid by forming new pores in the sclera. The effectiveness and safety of LASH is supported by a detailed example from clinical practice. This technology has proven itself as a possible alternative to the conventional contact transcleral cyclocoagulation.
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Affiliation(s)
- O V Khomchik
- Research Institute of Eye Diseases, Moscow, Russia
| | - N Y Yusef
- Research Institute of Eye Diseases, Moscow, Russia
| | - A A Gamidov
- Research Institute of Eye Diseases, Moscow, Russia
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35
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She M, Li B, Li T, Zhou X. Dynamic Changes of AREG in the Sclera during the Development of Form-Deprivation Myopia in Guinea Pigs. Curr Eye Res 2021; 47:477-483. [PMID: 34766531 DOI: 10.1080/02713683.2021.1998543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE To investigate amphiregulin (AREG) expression in the sclera during the development of form-deprivation myopia (FDM) and after the recovery of FDM in guinea pigs. METHODS Sixty-four 2-week-old guinea pigs were randomly divided into the control and FDM groups. The right eyes of animals in FDM group were covered for 2 weeks (2 W) and 4 weeks (4 W), or were covered for 4 weeks and then uncovered for the subsequent 2 weeks (6 W). The diopters and axial lengths (AL) in the right eyes of guinea pigs were measured. Reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence, and western blotting assays were used to detect the relative mRNA and protein expressions of AREG in the sclera of guinea pigs. RESULTS Before masking (0 W), the refraction and AL in the right eyes of guinea pigs in the control and FDM groups did not differ significantly (both p > .05). Myopic shift was induced in guinea pigs with the diopters gradually decreased and AL increased in the FDM group. While no significant difference was found in control group at different time points, the relative AREG mRNA and protein expression levels in the FDM group were significantly increased in 2 W and 4 W and then decreased after 4 weeks of covering followed by uncovering for 2 weeks (all p < .05). CONCLUSIONS AREG was expressed in the sclera of guinea pigs. Moreover, the expression levels of AREG increased during the development of FDM and downregulated after recovery of FDM. Therefore, AREG may be involved in the regulation of scleral remodeling in myopia.
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Affiliation(s)
- Man She
- Department of Ophthalmology, Jinshan Hospital of Fudan University, Shanghai, China
| | - Bing Li
- Central Laboratory, Jinshan Hospital Affiliated to Fudan University, Shanghai, China
| | - Tao Li
- Department of Ophthalmology, Jinshan Hospital of Fudan University, Shanghai, China
| | - Xiaodong Zhou
- Department of Ophthalmology, Jinshan Hospital of Fudan University, Shanghai, China
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36
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Hu D, Jiang J, Ding B, Xue K, Sun X, Qian S. Mechanical Strain Regulates Myofibroblast Differentiation of Human Scleral Fibroblasts by YAP. Front Physiol 2021; 12:712509. [PMID: 34658907 PMCID: PMC8514697 DOI: 10.3389/fphys.2021.712509] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 08/30/2021] [Indexed: 12/14/2022] Open
Abstract
Scleral extracellular matrix (ECM) remodeling is thought to play a critical role in the pathogenesis of glaucoma. Mechanical strain induced by elevated intraocular pressure can promote myofibroblast differentiation of fibroblasts and result in scleral ECM remodeling; however, the underlying mechanism remains poorly understood. Yes-associated protein (YAP) is a mechanosensory protein and the key downstream transcriptional effector of the Hippo signaling pathway. Here, we investigated the role of YAP in mechanical strain-induced myofibroblast transformation during glaucoma scleral ECM remodeling. Integrative bioinformatics analyses were performed to identify the key pathways for the ECM remodeling of the sclera in glaucoma. Sprague–Dawley rats were used to establish a chronic ocular hypertension model, and the expression of collagen type I (COL1) and YAP in the sclera was analyzed by immunohistochemical analysis and Western blotting. Furthermore, human scleral fibroblasts (HSFs) were cultured and subjected to mechanical strain. In groups with or without the YAP siRNA or YAP inhibitor, cell proliferation, migration capacity, and the expression levels of YAP, COL1, and α-smooth muscle actin (α-SMA) were evaluated by Cell Counting Kit-8 assay, scratch assay, and Western blotting. The interactions between YAP and Smad3 were demonstrated by coimmunoprecipitation, and the expression levels of COL1 and α-SMA were evaluated in groups treated with or without the Smad3 inhibitor. We first revealed that the Hippo signaling pathway may be involved in mechanical strain-induced scleral ECM remodeling through bioinformatics analysis. Furthermore, the in vivo study showed upregulated YAP, COL1, and α-SMA expression in the hypertensive sclera of rats. In vitro, mechanical strain increased YAP and COL1 expression in HSFs and promoted myofibroblast differentiation. After YAP knockdown or inhibition with verteporfin, mechanical strain-induced fibrotic changes in HSFs were markedly suppressed. Additionally, YAP showed a protein interaction with Smad3, and the upregulation of a-SMA and COL1 in response to mechanical strain was also significantly downregulated following the inhibition of Smad3. In conclusion, mechanical strain activated scleral myofibroblast differentiation via YAP. The YAP pathway may play an important role in regulating scleral myofibroblast differentiation and ECM remodeling of the sclera in glaucoma.
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Affiliation(s)
- Di Hu
- Department of Ophthalmology & Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,NHC Key Laboratory of Myopia, Chinese Academy of Medical Sciences, and Shanghai Key Laboratory of Visual Impairment and Restoration (Fudan University), Shanghai, China.,Department of Ophthalmology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Junhong Jiang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Baiyang Ding
- Spine Research Center of Wannan Medical College, Wuhu, China
| | - Kang Xue
- Department of Ophthalmology & Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,NHC Key Laboratory of Myopia, Chinese Academy of Medical Sciences, and Shanghai Key Laboratory of Visual Impairment and Restoration (Fudan University), Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology & Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,NHC Key Laboratory of Myopia, Chinese Academy of Medical Sciences, and Shanghai Key Laboratory of Visual Impairment and Restoration (Fudan University), Shanghai, China.,State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Shaohong Qian
- Department of Ophthalmology & Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,NHC Key Laboratory of Myopia, Chinese Academy of Medical Sciences, and Shanghai Key Laboratory of Visual Impairment and Restoration (Fudan University), Shanghai, China
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37
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Fernández-Vigo JI, Burgos-Blasco B, De-Pablo-Gómez-de-Liaño L, Kudsieh B, Fernández-Vigo JÁ. Implications of SS-OCT-anterior scleral thickness biometry on the definition of nanophthtalmos. Clin Exp Optom 2021; 105:453-454. [PMID: 34538203 DOI: 10.1080/08164622.2021.1973867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- José Ignacio Fernández-Vigo
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain.,Department of Ophthalmology, Centro Internacional de Oftalmología Avanzada, Madrid, Spain
| | - Bárbara Burgos-Blasco
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | | | - Bachar Kudsieh
- Department of Ophthalmology, Hospital Puerta de Hierro Majadahonda, Madrid, Spain
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Siva Jyothi EL, Gopala Krishna O, Lakshmana Rao P, Raja Sekhar P. Case series of scleral patch grafts during COVID-19 pandemic. Indian J Ophthalmol 2021; 69:2530-2532. [PMID: 34427260 PMCID: PMC8544111 DOI: 10.4103/ijo.ijo_3784_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Scleral graft is done for clinical conditions as scleral melt post pterygium surgery, immune or infection related scleral melt, for covering the tubes of Ahmed glaucoma valve implant, for covering the orbital implants post enucleation, etc. A review of literature revealed the use of sclera for corneal perforations in the past, but became obsolete after the cornea being used for patch grafts. Now in this COVID-19 time, due to scarcity of corneal tissue, this technique of scleral patch grafts can be considered as an alternative to corneal patch grafts, which serves well the tectonic/therapeutic purpose and helps salvage the eye.
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Affiliation(s)
- E Lalitha Siva Jyothi
- Chief Consultant, Cornea and Ocular Surface Disorders, Modern Eye Hospital and Research Center, Nellore, Andhra Pradesh, India
| | - O Gopala Krishna
- Chief Consultant and Medical Director, Cataract and Anterior Segment, Modern Eye Hospital and Research Center, Nellore, Andhra Pradesh, India
| | - P Lakshmana Rao
- Chief Consultant and Medical Director, Squint and Refractive Surgeries, Modern Eye Hospital and Research Center, Nellore, Andhra Pradesh, India
| | - P Raja Sekhar
- Chief Consultant, Department of Vitreo Retinal Services, Modern Retina Centre, Nellore, Andhra Pradesh, India
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Fernández-Vigo JI, Shi H, Burgos-Blasco B, Fernández-Aragón S, De-Pablo-Gómez-de-Liaño L, Kudsieh B, Macarro-Merino A, Fernández-Vigo JÁ. Anterior scleral thickness dimensions by swept-source optical coherence tomography. Clin Exp Optom 2021; 105:13-19. [PMID: 34134598 DOI: 10.1080/08164622.2021.1924629] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Clinical relevance: Given the association of scleral characteristics with many ophthalmological diseases, there is an important need to measure the anterior scleral thickness (AST).Background: This study examined the AST by swept-source optical coherence tomography (SS-OCT) in a large healthy population, assessing also the reproducibility of AST measurements and the correlation with different parameters.Methods: Cross-sectional study in 605 eyes of 605 subjects. AST measurements were made in the temporal and nasal quadrants at 1 (AST1) and 3 mm (AST3) from the scleral spur using SS-OCT. These dimensions were then assessed for associations in a multivariate model with the factors age, sex, refractive error, conjunctival-Tenon capsule thickness (CTT), anterior chamber angle (ACA), intraocular pressure (IOP), iris thickness (IT), limbus-sulcus distance (LSD), and ciliary muscle thickness (CMT). The reproducibility of the AST measurements was determined in 30 of the participants.Results: The mean age was 42.6 ± 17.3 years (range 5 to 86 years). The following means were recorded: AST1 was 522.3 ± 65.7 µm (355 to 761) and 558.4 ± 71.5 µm (357 to 889); AST2 was 513.3 ± 67.3 µm (343 to 732) and 574.4 ± 71.6 µm (389 to 789), and AST3 548.8 ± 71.9 µm (356 to 762) and 590.1 ± 76.6 µm (414 to 873) in the temporal and nasal quadrants respectively, being thicker the nasal quadrant (all p < 0.001). A positive correlation was detected between AST and age, sex, temporal ACA and LSD (all p ≤ 0.043), being negative the correlation with CMT (p ≤ 0.044). No correlation was observed between AST measurements and refractive error, CTT and IT (p ≥ 0.064). The reproducibility of AST measurements was excellent (intraclass correlation coefficient ≥0.951).Conclusions: SS-OCT allows for in vivo AST measurements. Our data contained a wide range of measurements, showing an association between AST and age, sex, ACA, LSD and CMT.
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Affiliation(s)
- José Ignacio Fernández-Vigo
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | - Hang Shi
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | - Bárbara Burgos-Blasco
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | | | | | - Bachar Kudsieh
- Department of Ophthalmology, Hospital Puerta de Hierro Majadahonda, Madrid, Spain
| | - Ana Macarro-Merino
- Department of Ophthalmology, Centro Internacional de Oftalmología Avanzada, Madrid, Spain
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40
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Vanhonsebrouck E, Consejo A, Coucke PJ, Leroy BP, Kreps EO. The corneo scleral shape in Marfan syndrome. Acta Ophthalmol 2021; 99:405-410. [PMID: 32996688 DOI: 10.1111/aos.14636] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 07/07/2020] [Accepted: 09/02/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE To investigate the corneoscleral shape in Marfan syndrome (MFS) patients. METHODS Thirty eyes of 15 participants with molecularly proven MFS were included in this prospective, cross-sectional study. Optical biometry, Scheimpflug imaging, and corneoscleral topography (Eye Surface Profiler) were performed in all patients. Topographic data were compared to data from controls (25 emmetropes and 17 myopes). The raw three-dimensional anterior height data from MFS eyes and control eyes were exported for further analysis. Custom-made software was used to demarcate the limbal radius and to calculate the sagittal height in different concentric annuli centred at the corneal apex, placed in a pupil plane, for the central cornea (0-4 mm radius), peripheral cornea (4-6 mm radius) and sclera (6-8 mm radius) and the corneoscleral asymmetry. RESULTS Marfan syndrome (MFS) eyes had significantly lower values of mean sagittal height compared to non-MFS eyes in all three annuli (central cornea, corneal periphery and sclera (independent t-test, p < 0.01 except for the inferior area of the scleral radius: p > 0.05). The sclera was significantly more asymmetric in MFS eyes compared to myopes (independent t-test, p < 0.01 for both eyes), but similar to emmetropes (independent t-test, p = 0.17 and p = 0.93 for right and left eyes, respectively). In MFS eyes, scleral asymmetry was not found to be correlated with axial length (Pearson correlation coefficient, r < 0.30, p > 0.05). CONCLUSION The peripheral cornea and sclera of Marfan syndrome patients have a significantly different shape compared to healthy controls.
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Affiliation(s)
| | - Alejandra Consejo
- Institute of Physical Chemistry Polish Academy of Sciences Warsaw Poland
| | - Paul J. Coucke
- Center for Medical Genetics Ghent University Hospital Ghent Belgium
| | - Bart P. Leroy
- Department of Ophthalmology Ghent University Hospital Ghent Belgium
- Center for Medical Genetics Ghent University Hospital Ghent Belgium
- Division of Ophthalmology & Center for Cellular & Molecular Therapeutics Children’s Hospital of Philadelphia Philadelphia USA
| | - Elke O. Kreps
- Department of Ophthalmology Ghent University Hospital Ghent Belgium
- Faculty of Medical Sciences Antwerp University Antwerp Belgium
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Abstract
The procedure involved an ab-externo scleral fixation technique using a double-armed 10-0 polypropylene suture with straight needles that require no scleral flaps. The IOLs are sutured to the sclera, the free suture ends are tied to the suture loops, and they are buried together under the sclera. Forty eyes of 37 patients were included. Postoperative complications are IOL capture in five eyes (12.5%), a significant IOL tilt in one eye (2.5%), recurrent UGH (uveitis-glaucoma-hyphema) syndrome in two eyes (5%), glaucoma in three eyes (7.5%), suture exposure in two eyes (5%) and IOL drop due to haptic breakage in one eye (2.5%). The technique can be effectively used for the refixation of dislocated hydrophobic acrylic IOLs by temporary haptic externalization through a corneal incision and for the treatment of aphakia with or without penetrating keratoplasty. Surgeons should be aware of the possibility of UGH syndrome due to IOL capture, especially in young eyes.
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Affiliation(s)
- Emre Altinkurt
- Istanbul University, Istanbul Faculty of Medicine, Department of Ophthalmology, Istanbul, Turkey
| | - Gizem Sayar Bilgin
- Istanbul University, Istanbul Faculty of Medicine, Department of Ophthalmology, Istanbul, Turkey
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Kumar RM, Konana VK, Kanakamedla A, Gudimetla J, Poluri S, Potti S. Modified balanced two-string technique of internal scleral fixation of posteriorly dislocated intraocular lens. Indian J Ophthalmol 2021; 69:762-764. [PMID: 33595521 PMCID: PMC7942082 DOI: 10.4103/ijo.ijo_922_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Posterior dislocation of the intraocular lens (IOL) is a rare but potentially dangerous complication encountered by a cataract surgeon. We describe a modified balanced two-string technique of internally fixing a posteriorly dislocated rigid IOL using the pars plana approach in eyes which lack adequate capsular support. Five eyes of five patients underwent the procedure. All eyes had successful IOL refixation. One eye had mild temporal decentration. BCVA improved in all patients. Our technique is an alternate method of scleral fixation of posteriorly dislocated IOL with advantages of minimal postoperative astigmatism, minimal anterior segment manipulation, and good IOL centration.
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Affiliation(s)
- R Madhu Kumar
- Department of Vitreoretina, Sankara Eye Hospital, Guntur, Andhra Pradesh, India
| | - Vinaya Kumar Konana
- Department of Vitreoretina, Sankara Eye Hospital, Guntur, Andhra Pradesh, India
| | - Ashok Kanakamedla
- Department of Vitreoretina, Sankara Eye Hospital, Guntur, Andhra Pradesh, India
| | | | - Swarnalatha Poluri
- Department of Vitreoretina, Sankara Eye Hospital, Guntur, Andhra Pradesh, India
| | - Sudhakar Potti
- Department of Vitreoretina, Sankara Eye Hospital, Guntur, Andhra Pradesh, India
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Dutt S, Vadivel SS, Nagarajan S, Galagali A, Christy JS, Sivaraman A, Rao DP. A novel approach to anterior segment imaging with smartphones in the COVID-19 era. Indian J Ophthalmol 2021; 69:1257-1262. [PMID: 33913872 PMCID: PMC8186572 DOI: 10.4103/ijo.ijo_3707_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Purpose: To report a novel, telemedicine-friendly, smartphone-based, wireless anterior segment device with instant photo-documentation ability in the COVID-19 era. Methods: Anterior Imaging Module (AIM) was constructed based on a 50/50 beam splitter design, to match the magnification drum optics of slit-lamps with a three-step or higher level of magnification. The design fills the smartphone sensor fully at the lowest magnification and matches the fixed focus of the slit-lamp. It comes with a smartphone for instant photo-documentation, an in-built software application for data-management and secure HIPAA compliant cloud storage, and a Bluetooth trigger for a one-tap image capture. The construction of the device is explained, and the optical resolution measured using U.S. air-force resolution test. AIM’s performance was characterized with traceability to internationally relevant performance standards for digital slit-lamps after image quality assessment through a pilot study. Results: Clinically useful anterior segment images were obtained with both diffuse and slit illumination at different magnification settings with the highest magnification (40X) resolution of 359 lines per cm and the lowest magnification (16X) resolution of 113 lines per cm. Conclusion: AIM is a novel, wireless, telemedicine-enabled design that digitizes existing, analog slit lamps with at least three-step magnification. The settings ensure the focus is determined purely by the position of the slit-lamp. Hence, the image viewed and captured on the smartphone is exactly what the clinician sees through the eyepiece. This helps in maintaining distance from the patient in the ongoing COVID-19 pandemic, as well.
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Affiliation(s)
- Sreetama Dutt
- Research & Development, Remidio Innovative Solutions Pvt. Ltd., Bengaluru, Karnataka, India
| | - Siva S Vadivel
- Research & Development, Remidio Innovative Solutions Pvt. Ltd., Bengaluru, Karnataka, India
| | | | - Amrutha Galagali
- Research & Development, Remidio Innovative Solutions Pvt. Ltd., Bengaluru, Karnataka, India
| | | | - Anand Sivaraman
- Research & Development, Remidio Innovative Solutions Pvt. Ltd., Bengaluru, Karnataka, India
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Abstract
Crosslinking involves the formation of bonds between polymer chains, such as proteins. In biological tissues, these bonds tend to stiffen the tissue, making it more resistant to mechanical degradation and deformation. In ophthalmology, the crosslinking phenomenon is being increasingly harnessed and explored as a treatment strategy for treating corneal ectasias, keratitis, degenerative myopia, and glaucoma. This review surveys the multitude of exogenous crosslinking strategies reported in the literature, both "light" (involving light energy) and "dark" (involving non-photic chemical processes), and explores their mechanisms, cytotoxicity, and stage of translational development. The spectrum of ophthalmic applications described in the literature is then discussed, with particular attention to proposed therapeutic mechanisms in the cornea and sclera. The mechanical effects of crosslinking are then discussed in the context of their proposed site and scale of action. Biomechanical characterization of the crosslinking effect is needed to more thoroughly address knowledge gaps in this area, and a review of reported methods for biomechanical characterization is presented with an attempt to assess the sensitivity of each method to crosslinking-mediated changes using data from the experimental and clinical literature. Biomechanical measurement methods differ in spatial resolution, mechanical sensitivity, suitability for detecting crosslinking subtypes, and translational readiness and are central to the effort to understand the mechanistic link between crosslinking methods and clinical outcomes of candidate therapies. Data on differences in the biomechanical effect of different crosslinking protocols and their correspondence to clinical outcomes are reviewed, and strategies for leveraging measurement advances predicting clinical outcomes of crosslinking procedures are discussed. Advancing the understanding of ophthalmic crosslinking, its biomechanical underpinnings, and its applications supports the development of next-generation crosslinking procedures that optimize therapeutic effect while reducing complications.
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Affiliation(s)
- Brecken J. Blackburn
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Andrew M. Rollins
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - William J. Dupps
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
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Li Y, Zhang F, Sun M, Lai L, Lv X, Liu C, Wang M, Wang N. Safety and Long-term Scleral Biomechanical Stability of Rhesus Eyes after Scleral Cross-linking by Blue Light. Curr Eye Res 2021; 46:1061-1070. [PMID: 33213212 DOI: 10.1080/02713683.2020.1853781] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Purpose: To assess the safety and long-term scleral biomechanical stability of rhesus eyes after blue light scleral CXL by investigating the biomechanical and microstructural changes.Methods: Seven rhesus monkeys (14 eyes) were observed in this study. All right eyes received blue light scleral CXL at the superior temporal equatorial sclera, and the left eyes served as controls. Biological ocular parameters were followed up to 1 year after scleral CXL. Stress-strain measurements of three rhesus sclera were measured, three rhesus retinas were examined histologically by H&E and TUNEL staining. And the microstructure of both the sclera and retina were observed by transmission electron microscopy at 1 year.Results: As for the retinal thickness, choroidal thickness, flow density of retinal superficial vascular networks and flash electroretinography (f-ERG) results, no significant differences were observed between the paired eyes at 1 year (P >.05). At the same time, the scleral collagen fibril distribution was much tighter, and the scleral biomechanical properties were significantly increased in the experimental eyes. However, apoptotic cells and retinal ultrastructural changes could still be found in the retina of the experimental eyes.Conclusion: This study demonstrates that blue light scleral CXL could effectively increase the scleral stiffness of the rhesus eye for at least 1 year, but ultrastructural change was still observed in the retina of scleral CXL eye. Therefore, the long-term intraocular safety of the blue light scleral CXL technique for preventing myopia progression should be investigated further.
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Affiliation(s)
- Yu Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Fengju Zhang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Mingshen Sun
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Lingbo Lai
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Xiaotong Lv
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Chong Liu
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
| | - Mengmeng Wang
- Hebei Ophthalmology Key Lab, Hebei Eye Hospital, Xingtai, Hebei Province, China
| | - Ningli Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, China
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46
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Aboulatta A, Abass A, Makarem A, Eliasy A, Zhou D, Chen D, Liu X, Elsheikh A. Experimental evaluation of the viscoelasticity of porcine vitreous. J R Soc Interface 2021; 18:20200849. [PMID: 33530856 DOI: 10.1098/rsif.2020.0849] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study aims to estimate the material properties of the porcine vitreous while testing it in close to its natural physiological conditions. Eighteen porcine eyes were tested within 48 h post-mortem. A custom-built computer-controlled test rig was designed to support, load and monitor the behaviour of eye globes while being subjected to dynamic rotation cycles mimicking saccade eye movement. Specimens were glued to the base of a container, surrounded by gelatin, frozen and cut in half to expose the vitreous. After thawing, the container was subjected to concentric dynamic rotations of up to 5°, 10° or 15°, while taking 50 MP photos of the specimen every 2 ms. The images were analysed by a digital image correlation algorithm to trace the movement of marked points on the vitreous surface with different radii from the centre of the posterior chamber. The initial camera image was used in building a finite-element model of the test set-up, which was used in an inverse analysis exercise to estimate the material properties of the vitreous. Angular displacements of the monitored points were up to 3.3°, 4.1° and 3.9° in response to eye rotations of 5°, 10° and 15°, respectively. With the experimental relationships between eye rotation and angular displacements used as target behaviour, the inverse analysis exercise estimated the initial shear modulus, the long-term shear modulus and the viscoelastic decay constant of the porcine vitreous as 2.10 ± 0.15 Pa, 0.50 ± 0.04 Pa and 1.20 ± 0.09 s-1, respectively. Consideration of the viscoelasticity of the vitreous was essential to represent its experimental behaviour. Testing the vitreous in close to its normal physiological conditions produced estimations of the initial shear modulus and long-term shear modulus that were, respectively, smaller and larger than reported values (Zimberlin et al. 2010 Soft Matter 6, 3632-3635. (doi:10.1039/b925407b), Liu et al. 2013 J. Biomech. 46, 1321-7. (doi:10.1016/j.jbiomech.2013.02.006), Rossi et al. 2011 Invest. Ophthalmol. Vis. Sci. 52, 3994-4002. (doi:10.1167/iovs.10-6477)).
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Affiliation(s)
- Ali Aboulatta
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK
| | - Ahmed Abass
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK
| | - Ahmed Makarem
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK
| | - Ashkan Eliasy
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK
| | - Dong Zhou
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK
| | - Duo Chen
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, People's Republic of China
| | - Xiaoyu Liu
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, People's Republic of China.,Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing 100083, People's Republic of China
| | - Ahmed Elsheikh
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK.,Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing 100083, People's Republic of China.,NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
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Lv W, Song Y, Fu R, Lin X, Su Y, Jin X, Yang H, Shan X, Du W, Huang Q, Zhong H, Jiang K, Zhang Z, Wang L, Huang G. Deep Learning Algorithm for Automated Detection of Polycystic Ovary Syndrome Using Scleral Images. Front Endocrinol (Lausanne) 2021; 12:789878. [PMID: 35154003 PMCID: PMC8828568 DOI: 10.3389/fendo.2021.789878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 12/15/2021] [Indexed: 11/15/2022] Open
Abstract
The high prevalence of polycystic ovary syndrome (PCOS) among reproductive-aged women has attracted more and more attention. As a common disorder that is likely to threaten women's health physically and mentally, the detection of PCOS is a growing public health concern worldwide. In this paper, we proposed an automated deep learning algorithm for the auxiliary detection of PCOS, which explores the potential of scleral changes in PCOS detection. The algorithm was applied to the dataset that contains the full-eye images of 721 Chinese women, among which 388 are PCOS patients. Inputs of the proposed algorithm are scleral images segmented from full-eye images using an improved U-Net, and then a Resnet model was applied to extract deep features from scleral images. Finally, a multi-instance model was developed to achieve classification. Various performance indices such as AUC, classification accuracy, precision, recall, precision, and F1-score were adopted to assess the performance of our algorithm. Results show that our method achieves an average AUC of 0.979 and a classification accuracy of 0.929, which indicates the great potential of deep learning in the detection of PCOS.
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Affiliation(s)
- Wenqi Lv
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Ying Song
- Reproductive Medicine Centre, Peking University Third Hospital, Beijing, China
| | - Rongxin Fu
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Xue Lin
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Ya Su
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Xiangyu Jin
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Han Yang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Xiaohui Shan
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Wenli Du
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Qin Huang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Hao Zhong
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Kai Jiang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | - Zhi Zhang
- National Engineering Research Center for Beijing Biochip Technology, Beijing, China
- *Correspondence: Zhi Zhang, ; Lina Wang, ; Guoliang Huang,
| | - Lina Wang
- Reproductive Medicine Centre, Peking University Third Hospital, Beijing, China
- *Correspondence: Zhi Zhang, ; Lina Wang, ; Guoliang Huang,
| | - Guoliang Huang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
- National Engineering Research Center for Beijing Biochip Technology, Beijing, China
- *Correspondence: Zhi Zhang, ; Lina Wang, ; Guoliang Huang,
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Hu D, Jiang J, Lin Z, Zhang C, Moonasar N, Qian S. Identification of key genes and pathways in scleral extracellular matrix remodeling in glaucoma: Potential therapeutic agents discovered using bioinformatics analysis. Int J Med Sci 2021; 18:1554-1565. [PMID: 33746571 PMCID: PMC7976561 DOI: 10.7150/ijms.52846] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 01/05/2021] [Indexed: 12/29/2022] Open
Abstract
Background: Glaucoma is a leading cause of irreversible blindness. Remodeling of the scleral extracellular matrix (ECM) plays an important role in the development of glaucoma. The aim of this study was to identify the key genes and pathways for the ECM remodeling of sclera in glaucoma by bioinformatics analysis and to explore potential therapeutic agents for glaucoma management. Methods: Genes associated with glaucoma, sclera and ECM remodeling were detected using the text mining tool pubmed2ensembl, and assigned Gene Ontology (GO) biological process terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways using the GeneCodis program. A protein-protein interaction (PPI) network was constructed by STRING and visualized in Cytoscape, module analysis was performed using the Molecular Complex Detection (MCODE) plugin, and GO and KEGG analyses of the gene modules were performed using the Database of Annotation, Visualization and Integrated Discovery (DAVID) platform. The genes that clustered in the significant module were selected as core genes, and functions and pathways of the core genes were visualized using ClueGO and CluePedia. Lastly, the drug-gene interaction database was used to explore drug-gene interactions of the core genes to find drug candidates for glaucoma. Results: We identified 125 genes common to "Glaucoma", "Sclera", and "ECM remodeling" by text mining. Gene functional enrichment analysis yielded 30 enriched GO terms and 20 associated KEGG pathways. A PPI network that included 60 nodes with 249 edges was constructed, and three gene modules were obtained using the MCODE. We selected 13 genes that clustered in module 1 as core candidate genes that were associated mainly with ECM degradation and cell proliferation and division. The HIF-1 signaling pathway, FOXO signaling pathway, PI3K-Akt signaling pathway and TGFB signaling pathway were found to be enriched. We found that 11 of the 13 selected genes could be targeted by 26 existing drugs. Conclusions: The results showed that VEGFA, TGFB1, TGFB2, TGFB3, IGF2, IGF1, EGF, FN1, KNG1, TIMP1, SERPINE1, THBS1, and VWF were potential key genes involved to scleral ECM remodeling. Furthermore, 26 drugs were identified as potential therapeutic agents for glaucoma treatment and management.
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Affiliation(s)
- Di Hu
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Junhong Jiang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhong Lin
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Cong Zhang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | | | - Shaohong Qian
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
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49
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Markov P, Hayes AJ, Zhu H, Boote C, Blain EJ. 3D immuno-confocal image reconstruction of fibroblast cytoskeleton and nucleus architecture. J Biophotonics 2021; 14:e202000202. [PMID: 33038053 DOI: 10.1002/jbio.202000202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 09/28/2020] [Accepted: 10/07/2020] [Indexed: 06/11/2023]
Abstract
Computational models of cellular structures generally rely on simplifying approximations and assumptions that limit biological accuracy. This study presents a comprehensive image processing pipeline for creating unified three-dimensional (3D) reconstructions of the cell cytoskeletal networks and nuclei. Confocal image stacks of these cellular structures were reconstructed to 3D isosurfaces (Imaris), then tessellations were simplified to reduce the number of elements in initial meshes by applying quadric edge collapse decimation with preserved topology boundaries (MeshLab). Geometries were remeshed to ensure uniformity (Instant Meshes) and the resulting 3D meshes exported (ABAQUS) for downstream application. The protocol has been applied successfully to fibroblast cytoskeletal reorganisation in the scleral connective tissue of the eye, under mechanical load that mimics internal eye pressure. While the method herein is specifically employed to reconstruct immunofluorescent confocal imaging data, it is also more widely applicable to other biological imaging modalities where accurate 3D cell structures are required.
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Affiliation(s)
- Petar Markov
- School of Biosciences, Cardiff University, Cardiff, Wales, UK
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, UK
- School of Engineering, Cardiff University, Cardiff, Wales, UK
| | - Anthony J Hayes
- Bioimaging Research Hub, School of Biosciences, Cardiff University, Cardiff, Wales, UK
| | - Hanxing Zhu
- School of Engineering, Cardiff University, Cardiff, Wales, UK
| | - Craig Boote
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, UK
| | - Emma J Blain
- School of Biosciences, Cardiff University, Cardiff, Wales, UK
- Biomechanics and Bioengineering Centre Versus Arthritis, School of Biosciences, Cardiff University, Cardiff, Wales, UK
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50
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Consejo A, Wu R, Abass A. Anterior Scleral Regional Variation between Asian and Caucasian Populations. J Clin Med 2020; 9:jcm9113419. [PMID: 33113864 PMCID: PMC7692638 DOI: 10.3390/jcm9113419] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/13/2020] [Accepted: 10/21/2020] [Indexed: 02/06/2023] Open
Abstract
Purpose: To evaluate the anterior scleral shape regional differences between Asian and Caucasian populations. Methods: The study included 250 Asian eyes and 235 Caucasian eyes from participants aged 22 to 67 years (38.5 ± 7.6). Three-dimensional (3D) corneo-scleral maps were acquired using a corneo-scleral topographer (Eye Surface Profiler, Eaglet Eye BV) and used to calculate sagittal height. For each 3D map, the sclera (maximum diameter of 18 mm) and cornea were separated at the limbus using an automated technique. Advanced data processing steps were applied to ensure levelled artefact-free datasets to build an average scleral shape map for each population. Results: Statistically, Asian and Caucasian sclerae are significantly different from each other in sagittal height (overall sclera, p = 0.001). The largest difference in sagittal height between groups was found in the inferior-temporal region (271 ± 203 µm, p = 0.03), whereas the smallest difference was found in the superior-temporal region (84 ± 105 µm, p = 0.17). The difference in sagittal height between Caucasian and Asian sclera increases with the distance from the limbus. Conclusions: Asian anterior sclera was found to be less elevated than Caucasian anterior sclera. However, the nasal area of the sclera is less elevated than the temporal area, independently of race. Gaining knowledge in race-related scleral topography differences could assist contact lens manufacturers in the process of lens design and practitioners during the process of contact lens fitting.
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Affiliation(s)
- Alejandra Consejo
- Institute of Physical Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland;
- Department of Applied Physics, University of Zaragoza, 50009 Zaragoza, Spain
| | - Richard Wu
- Department of Optometry, Central Taiwan University of Science and Technology, Taichung City 40601, Taiwan;
- College of Optometry, Pacific University, Forest Grove, OR 97116, USA
| | - Ahmed Abass
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK
- Correspondence:
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