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Vahedi H, Abdollahi M, Moshfeghinia R, Emami S, Sobhi N, Sorkhabi R, Jafarizadeh A. Retinal thickness and vascular density changes in Keratoconus: A systematic review and meta-analysis. Heliyon 2025; 11:e42099. [PMID: 39925350 PMCID: PMC11804566 DOI: 10.1016/j.heliyon.2025.e42099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2024] [Revised: 01/11/2025] [Accepted: 01/17/2025] [Indexed: 02/11/2025] Open
Abstract
Purpose This systematic review and meta-analysis aimed to assess the changes in retinal layer thickness and vascular density in patients diagnosed with keratoconus (KC). Methods We conducted a thorough search in PubMed, Scopus, Embase, and Web of Science, encompassing all observational studies from January 1990 to February 2024. We analyzed the data using STATA software 17 and the random effects model with the restricted maximum likelihood (REML) or maximum likelihood (ML) method to pool the standardized mean difference (SMD) and the weighted mean difference (WMD) of retinal thickness and vascular density compared to non-KC eyes. Results From 4608 records, 16 primary studies met our inclusion criteria, involving 1932 eyes in two groups. The meta-analysis revealed a significant reduction in retinal nerve fiber layer (RNFL) thickness (SMD: -0.30 [-0.52, -0.08]), perifoveal macular thickness in the nasal region (SMD: -0.32 [-0.55, -0.09]) and superior region (SMD: -0.24 [-0.47, -0.02]), and superior capillary plexus (SCP) density (SMD: -1.52 [-2.27, -0.77]) of KC eyes. Additionally, there was a mildly to moderately significant increase in the optic nerve head (ONH) disk area (SMD: 0.40 [0.06, 0.75]). However, there were no significant changes in foveal macular thickness, parafoveal macular thickness, or deep capillary plexus (DCP) density. Conclusion In KC patients, significant alterations in retinal structure and vascular density have been observed. Although these changes do not currently influence treatment strategies, they offer valuable insights into the relationship between the retina and the cornea. Understanding these changes may be essential for future research focused on early detection, potential prognosis markers, and further exploration of the retina-corneal connection in KC.
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Affiliation(s)
- Hadi Vahedi
- Nikookari Eye Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mirsaeed Abdollahi
- Nikookari Eye Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Moshfeghinia
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Shima Emami
- Research Center for Evidence-Based Medicine, Iranian EBM Centre: A Joanna Briggs Institute Affiliated Group, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Navid Sobhi
- Nikookari Eye Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Rana Sorkhabi
- Nikookari Eye Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Ophthalmology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Jafarizadeh
- Nikookari Eye Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Feo A, Vinciguerra R, Antropoli A, Barone G, Criscuolo D, Vinciguerra P, Romano V, Romano MR. Pachychoroid pigment epitheliopathy in keratoconic eyes. Graefes Arch Clin Exp Ophthalmol 2025; 263:87-95. [PMID: 39212800 DOI: 10.1007/s00417-024-06612-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 07/18/2024] [Accepted: 08/09/2024] [Indexed: 09/04/2024] Open
Abstract
PURPOSE To report the association between keratoconus (KC) and pachychoroid pigment epitheliopathy (PPE). As secondary outcome, we explored the relation between subfoveal choroidal thickness (SFCT) and topometric indexes. METHODS Retrospective, observational, cross-sectional, case-control study. Multicentric study including patients with KC and healthy controls. Each subject underwent a complete ophthalmological visit, Placido-based corneal topography, Scheimpflug corneal tomography and spectral-domain OCT (SD-OCT) with the enhanced depth imaging (EDI) mode on. Linear mixed models (LMM) were employed for comparison between groups, and to examine the impact of different topometric factors on SFCT. KC stages were defined according to Belin grading. RESULTS Overall, 56 eyes from 35 KC patients and 52 eyes from 27 healthy, age- and axial length-matched control subjects were included in the study. PPE was found in 10 (17.9%) eyes from 8 KC patients, whereas was absent in all healthy controls. SFCT was statistically significantly higher in keratoconic eyes (median: 390 µm; interquartile range (IQR): 339 - 425 µm) compared to healthy eyes (median: 240 µm; IQR: 200 - 288 µm) (p < 0.001). SFCT did not differ across different KC stages and between keratoconic eyes with and without PPE. CONCLUSIONS PPE is a relatively frequent finding in eyes with KC, being present in about 1 out of 6 cases, regardless of disease stage. KEY MESSAGES What is known: Keratoconus (KC) is a corneal disorder commonly associated with other chorioretinal abnormalities. It is well known that keratoconic eyes display increased choroidal thickness, and the rare association between KC and central serous chorioretinopathy (CSC) has already been reported in the literature. WHAT IS NEW We identified an association between KC and pachychoroid pigment epitheliopathy (PPE), a precursor or forme fruste of pachychoroid diseases, such as CSC. PPE presence is independent from corneal parameters and is observed in about 1 out 6 KC eyes.
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Affiliation(s)
- Alessandro Feo
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072, Milan, Italy.
| | | | - Alessio Antropoli
- Ophthalmology Department, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Gianmaria Barone
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072, Milan, Italy
| | - Daniele Criscuolo
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072, Milan, Italy
| | - Paolo Vinciguerra
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072, Milan, Italy
| | - Vito Romano
- Opththalmic Unit, Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Viale Europa 15, 25123, Brescia, Italy
| | - Mario R Romano
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072, Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, Bergamo, Italy
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Burguera-Giménez N, Díez-Ajenjo MA, Briceno-Lopez C, Burguera N, Luque-Cobija MJ, Peris-Martínez C. Relationship between Choroidal Thickness and Anterior Scleral Thickness in Patients with Keratoconus. Diagnostics (Basel) 2024; 14:2280. [PMID: 39451603 PMCID: PMC11505922 DOI: 10.3390/diagnostics14202280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2024] [Revised: 10/04/2024] [Accepted: 10/12/2024] [Indexed: 10/26/2024] Open
Abstract
PURPOSE To evaluate the relationship between choroidal thickness (CT) and anterior scleral thickness (AST) in patients with subclinical keratoconus (SKC) and established keratoconus (KC). METHODS This single-center prospective case-control study included 97 eyes of 97 patients: 44 KC eyes, 14 SKC eyes, and 39 age- and axial length (AL)-matched healthy eyes. Using swept-source optical coherence tomography, the AST was manually measured in four directions and the CT was obtained automatically from the Early Treatment Diabetic Retinopathy Study (ETDRS) grid. Principal component analysis (PCA) was used to linearly reduce the dimensionality of nine CT inputs to one significant component, CT1. A multivariate model was created to evaluate the association between CT1, AST, and several ocular parameters in SKC and KC patients. Partial correlation was then performed to adjust the confounding factors and to examine the effect of AST on CT1. RESULTS The PCA showed that CT1 accounts for 86.54% of the total variance in the nine original CTs of the ETDRS grid. The CT1 model was associated with age, AL, and AST in the superior meridian in SKC eyes, whereas in KC eyes, it was correlated with gender, age, AL, and AST in the inferior meridian (p < 0.001). The partial correlation between CT1 and AST in the superior zone was found to be significant, positive, and strong in SKC eyes (r = 0.79, p = 0.019), whereas a significant, positive, and moderate correlation between CT1 and AST at the inferior zone (r = 0.41, p = 0.017) was observed in KC eyes. CONCLUSIONS Choroidal tissue was significantly correlated with the anterior sclera across the vertical meridian. This relationship was observed over the superior sclera in SKC eyes, whereas in established KC, it was over the inferior sclera. These results reveal new insights regarding the interactions between the anterior and posterior structures of the KC eyes and confirm the enigma of the pathophysiology of KC.
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Affiliation(s)
- Neus Burguera-Giménez
- Anterior Segment, Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Av. Pío Baroja, 12, E-46015 Valencia, Spain; (M.A.D.-A.); (C.B.-L.); (C.P.-M.)
- Department of Optics, Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain;
| | - M.ª Amparo Díez-Ajenjo
- Anterior Segment, Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Av. Pío Baroja, 12, E-46015 Valencia, Spain; (M.A.D.-A.); (C.B.-L.); (C.P.-M.)
- Department of Optics, Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain;
| | - Celeste Briceno-Lopez
- Anterior Segment, Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Av. Pío Baroja, 12, E-46015 Valencia, Spain; (M.A.D.-A.); (C.B.-L.); (C.P.-M.)
- Department of Optics, Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain;
| | - Noemí Burguera
- Ophthalmology Department, Q Vision, Vithas Virgen del Mar Hospital, Ctra. el Mami a Viator, Km.1, E-04120 Almería, Spain;
| | - M.ª José Luque-Cobija
- Department of Optics, Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, E-46100 Valencia, Spain;
| | - Cristina Peris-Martínez
- Anterior Segment, Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Av. Pío Baroja, 12, E-46015 Valencia, Spain; (M.A.D.-A.); (C.B.-L.); (C.P.-M.)
- Surgery Department, Ophthalmology, School of Medicine, University of Valencia, Av. Blasco Ibáñez, 15, E-46010 Valencia, Spain
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Marta A, Ferreira A, Couto I, Neves MM, Gomes M, Oliveira L, Azevedo Soares C, Menéres MJ, Lemos C, Melo Beirão J. Corneal Biomechanical Changes in Patients with Inherited Retinal Diseases. Clin Ophthalmol 2024; 18:2611-2618. [PMID: 39318485 PMCID: PMC11420929 DOI: 10.2147/opth.s478846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2024] [Accepted: 09/12/2024] [Indexed: 09/26/2024] Open
Abstract
Purpose Inherited retinal diseases (IRDs) are a group of degenerative disorders of the retina, that can be potentially associated with changes in the anterior segment, but their prevalence and impact are not known. Exploring these concomitant ophthalmologic changes with biomechanical assessment may help identify other non-retina causes of vision loss in these patients, such as corneal ectasia or susceptibility to glaucoma. This study aimed to measure and compare corneal biomechanics in patients with and without IRDs. Methods A total of 77 patients (154 eyes) with IRD were recruited as the study group. The control group consisted of 77 healthy adults (154 eyes) with matched age and sphere equivalents. All participants underwent a comprehensive assessment including corneal tomography (Pentacam®) and biomechanical assessment (Corvis ST®). A total of 4 second-generation biomechanical parameters and 3 indexes were collected: Ambrosio Relational Thickness (ARTh), Deflection Amplitude Ratio Max (DARM), Integrated Radius (IR) and Stiffness Parameter at Applanation (SP-A1), the final deviation value D of the Belin/Ambrosio Enhanced Ectasia Display (BAD-D), Corvis Biomechanical Index (CBI) and Tomographic Biomechanical Index (TBI). Results For IRD patients, there was a higher DARM (p < 0.001), lower ARTh (p < 0.001), higher CBI (p < 0.001), higher TBI (p<0.001), and higher BAD-D (p < 0.001) compared to the control group. Regarding discrimination of healthy subjects and IRD patients, ARTh was the most sensitive parameter. Conclusion The results showed that IRD patients tend to have softer corneal behaviour, compared to eyes without pathology, which may predispose patients to corneal ectasia or glaucoma development. ARTh could be used to screen IRD patients if a non-retina cause of vision loss is suspected.
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Affiliation(s)
- Ana Marta
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
- Instituto Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal
| | - André Ferreira
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
- Department of Biomedicine - Unit of Anatomy, Faculty of Medicine of University of Porto, Porto, Portugal
- Centre for Health Technology and Services Research, Health Research Network (CINTESIS@RISE), Faculty of Medicine of the University of Porto, Porto, Portugal
| | - Inês Couto
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
| | - Miguel Mesquita Neves
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
| | - Miguel Gomes
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
| | - Luis Oliveira
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
| | - Celia Azevedo Soares
- Medical Genetics Department, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
- Unit for Multidisciplinary Research in Biomedicine, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
- Medical Science Department, Universidade de Aveiro, Aveiro, Portugal
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Maria João Menéres
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
- Instituto Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal
| | - Carolina Lemos
- Instituto Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - João Melo Beirão
- Department of Ophthalmology, Centro Hospitalar Universitário de Santo António, Unidade Local de Saúde de Santo António, Porto, Portugal
- Instituto Ciências Biomédicas Abel Salazar (ICBAS), Porto, Portugal
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Abbasi Mehrabadi A, Sadeghi J, Shoeibi N, Heravian Shandiz J, Motamed Shariati M, Derakhshan A, Yazdani N. Macular choroidal thickness in keratoconus. Clin Exp Optom 2024:1-6. [PMID: 39189829 DOI: 10.1080/08164622.2024.2393189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 08/11/2024] [Accepted: 08/12/2024] [Indexed: 08/28/2024] Open
Abstract
CLINICAL RELEVANCE Expanding practitioner knowledge regarding potential changes in ocular structure of keratoconic eyes will improve the eye care practice and patient management. BACKGROUND This study aimed to compare the difference in choroidal thickness between keratoconus patients and two control groups of myopic-astigmatism and emmetropic subjects. METHODS A case-control study was undertaken which included 50 patients with keratoconus, 50 with myopic-astigmatism, 30 with emmetropia aged between 18 and 39 years. Choroidal thickness was measured at three different locations, including the subfoveal, nasal, and temporal (750 micrometres) to the fovea, using a spectral-domain optical coherence tomography with an enhanced depth imaging technique. RESULTS The mean spherical equivalents were 0.03 ± 0.05, -3.00 ± 0.2, and -3.00 ± 0.3 dioptre in emmetropic, myopic-astigmatism and keratoconus subjects, respectively. The choroid was significantly thicker in keratoconus patients than in myopic-astigmatism and emmetropic subjects in the subfoveal (396 ± 14, 314 ± 12, and 320 ± 18 μm, respectively, p < 0.001), temporal (405 ± 14, 317 ± 12, and 328 ± 19 μm, respectively, p < 0.001) and nasal (376 ± 14, 285 ± 12, and 311 ± 18 μm, respectively; p < 0.001). CONCLUSION Choroidal thickness is increased in keratoconus. The exact mechanism for choroidal thickening in individuals with keratoconus is unknown, but inflammatory responses could be the reason.
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Affiliation(s)
| | - Javad Sadeghi
- Eye Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Nasser Shoeibi
- Eye Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | | | - Akbar Derakhshan
- Eye Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Negareh Yazdani
- Refractive Errors Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
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Leclaire MD, Storp JJ, Lahme L, Esser EL, Eter N, Alnawaiseh M. Reduced Retinal Blood Vessel Densities Measured by Optical Coherence Tomography Angiography in Keratoconus Patients Are Negatively Correlated with Keratoconus Severity. Diagnostics (Basel) 2024; 14:707. [PMID: 38611620 PMCID: PMC11011292 DOI: 10.3390/diagnostics14070707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 03/15/2024] [Accepted: 03/25/2024] [Indexed: 04/14/2024] Open
Abstract
Keratoconus (KC) is the most common corneal ectasia. Optical coherence tomography angiography (OCT-A) is a relatively new non-invasive imaging technique that allows the visualization and quantification of retinal and choriocapillary blood vessels. The aim of this study is to assess retinal and choriocapillary vessel density (VD) differences between KC patients and healthy controls and to investigate correlations between VD and KC severity. Fifty-two eyes were included in this exploratory study: twenty-six eyes from 26 KC patients and twenty-six eyes from 26 age- and gender-matched healthy controls. All patients underwent Scheimpflug corneal topography with Pentacam, axis lengths measurement and optical coherence tomography angiography (OCT-A). The thinnest spot in corneal pachymetry, maximum K (Kmax) and KC severity indices from the Belin/Ambrósio enhanced ectasia display (BAD) were also assessed. There was a distinct reduction particularly in the retinal VD of the superficial capillary plexus (SCP). Correlation analyses showed strong and moderate negative correlations between the VD in the macular SCP and BAD KC scores and between the SCP VD and Kmax. There was no difference in retinal thickness between the KC and healthy controls. With this study, further evidence for altered VD measurements by OCT-A in KC patients is given. For the first time, we demonstrated negative correlations between BAD KC scores and retinal blood vessel alterations. A major limitation of the study is the relatively small sample size. Since an artefactual reduction of the quantitative OCT-A measurements due to irregular corneal topography in KC must be assumed, it remains to be investigated whether there are also actual changes in the retinal microcirculation in KC.
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Affiliation(s)
- Martin Dominik Leclaire
- Department of Ophthalmology, University Medical Center Münster, 48149 Münster, Germany; (J.J.S.); (E.L.E.); (N.E.)
| | - Jens Julian Storp
- Department of Ophthalmology, University Medical Center Münster, 48149 Münster, Germany; (J.J.S.); (E.L.E.); (N.E.)
| | - Larissa Lahme
- Department of Ophthalmology, University Medical Center Münster, 48149 Münster, Germany; (J.J.S.); (E.L.E.); (N.E.)
| | - Eliane Luisa Esser
- Department of Ophthalmology, University Medical Center Münster, 48149 Münster, Germany; (J.J.S.); (E.L.E.); (N.E.)
| | - Nicole Eter
- Department of Ophthalmology, University Medical Center Münster, 48149 Münster, Germany; (J.J.S.); (E.L.E.); (N.E.)
| | - Maged Alnawaiseh
- Department of Ophthalmology, Klinikum Bielefeld gem. GmbH, 33647 Bielefeld, Germany
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Burguera-Giménez N, Díez-Ajenjo MA, Burguera N, Briceno-Lopez C, Peris-Martínez C. Subfoveal and Parafoveal Choroidal Thickening in Patients with Keratoconus Using the ETDRS Grid on Swept-Source OCT. Ophthalmol Ther 2024; 13:509-527. [PMID: 38113025 PMCID: PMC10787729 DOI: 10.1007/s40123-023-00858-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/20/2023] [Indexed: 12/21/2023] Open
Abstract
INTRODUCTION There is growing evidence that confirms morphological changes in the posterior structures in patients with keratoconus (KC); however, isolated alterations could have been missed. This study assesses choroidal thickness (CT) in the fovea and beyond in KC eyes. METHODS This prospective case-control and non-randomized study enrolled 107 eyes, 62 eyes of 62 patients with KC, and 45 age-matched eyes of 45 control subjects with axial length in the range of 22-26 mm. Swept-source optical coherence tomography (SS-OCT) was performed to manually measure the subfoveal choroidal thickness (SCT) using a single-line scan. CT was obtained automatically from the Early Treatment Diabetic Retinopathy Study (ETDRS) grid using the 12-lines radial scan pattern. A two-way repeated-measures analysis of variance (ANOVA) was conducted to evaluate CT variations among macular eccentricity, parafoveal area, and the interaction between both factors. CT was compared in all parafoveal areas between groups and subgroups of KC. RESULTS SCT was significantly thicker in KC eyes (357 ± 57 µm) than in healthy eyes (325 ± 63 µm) (p < 0.001). Significant choroidal thickening was observed in the central ring and outer and inner rings of the temporal, superior, and inferior parafoveal macular areas (p < 0.001), except in the outer ring of the nasal macular zone (p > 0.05) of KC compared to healthy eyes. The CT significantly decreased from the center to the outer ring regardless of the presence of KC (p < 0.001). The choroid in the nasal macular zone was significantly thinner than that in the temporal, superior, and inferior parafoveal areas (p < 0.001). CONCLUSIONS The choroidal structure increased its thickness not only in the subfoveal area, but also in eight parafoveal areas of the ETDRS grid encompassing a wider area of macular examination. These findings demonstrate and corroborate that keratoconus is not a purely corneal disease. Furthermore, it confirms the role that the choroidal structure has in the pathophysiology of keratoconus.
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Affiliation(s)
- Neus Burguera-Giménez
- Anterior Segment and Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Avda. Pío Baroja, 12, 46015, Valencia, Spain.
- Department of Optics and Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, 46100, Valencia, Spain.
| | - Mª Amparo Díez-Ajenjo
- Anterior Segment and Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Avda. Pío Baroja, 12, 46015, Valencia, Spain
- Department of Optics and Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, 46100, Valencia, Spain
| | - Noemí Burguera
- Ophthalmology Department, Q Vision, Vithas Virgen del Mar Hospital, Ctra. el Mami a Viator, Km.1, 04120, Almería, Spain
| | - Celeste Briceno-Lopez
- Anterior Segment and Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Avda. Pío Baroja, 12, 46015, Valencia, Spain
- Department of Optics and Optometry and Vision Sciences, Physics School, University of Valencia, Dr. Moliner, 50, 46100, Valencia, Spain
| | - Cristina Peris-Martínez
- Anterior Segment and Cornea and External Eye Diseases Unit, Fundación de Oftalmología Médica (FOM), Avda. Pío Baroja, 12, 46015, Valencia, Spain
- Surgery Department, Ophthalmology, School of Medicine, University of Valencia, Av. Blasco Ibáñez, 15, 46010, Valencia, Spain
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Choi JY, Kim H, Kim JK, Lee IS, Ryu IH, Kim JS, Yoo TK. Deep learning prediction of steep and flat corneal curvature using fundus photography in post-COVID telemedicine era. Med Biol Eng Comput 2024; 62:449-463. [PMID: 37889431 DOI: 10.1007/s11517-023-02952-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 10/14/2023] [Indexed: 10/28/2023]
Abstract
Recently, fundus photography (FP) is being increasingly used. Corneal curvature is an essential factor in refractive errors and is associated with several pathological corneal conditions. As FP-based examination systems have already been widely distributed, it would be helpful for telemedicine to extract information such as corneal curvature using FP. This study aims to develop a deep learning model based on FP for corneal curvature prediction by categorizing corneas into steep, regular, and flat groups. The EfficientNetB0 architecture with transfer learning was used to learn FP patterns to predict flat, regular, and steep corneas. In validation, the model achieved a multiclass accuracy of 0.727, a Matthews correlation coefficient of 0.519, and an unweighted Cohen's κ of 0.590. The areas under the receiver operating characteristic curves for binary prediction of flat and steep corneas were 0.863 and 0.848, respectively. The optic nerve and its peripheral areas were the main focus of the model. The developed algorithm shows that FP can potentially be used as an imaging modality to estimate corneal curvature in the post-COVID-19 era, whereby patients may benefit from the detection of abnormal corneal curvatures using FP in the telemedicine setting.
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Affiliation(s)
- Joon Yul Choi
- Department of Biomedical Engineering, Yonsei University, Wonju, South Korea
| | | | - Jin Kuk Kim
- Department of Refractive Surgery, B&VIIT Eye Center, B2 GT Tower, 1317-23 Seocho-Dong, Seocho-Gu, Seoul, South Korea
| | - In Sik Lee
- Department of Refractive Surgery, B&VIIT Eye Center, B2 GT Tower, 1317-23 Seocho-Dong, Seocho-Gu, Seoul, South Korea
| | - Ik Hee Ryu
- Department of Refractive Surgery, B&VIIT Eye Center, B2 GT Tower, 1317-23 Seocho-Dong, Seocho-Gu, Seoul, South Korea
- Research and Development Department, VISUWORKS, Seoul, South Korea
| | - Jung Soo Kim
- Research and Development Department, VISUWORKS, Seoul, South Korea
| | - Tae Keun Yoo
- Department of Refractive Surgery, B&VIIT Eye Center, B2 GT Tower, 1317-23 Seocho-Dong, Seocho-Gu, Seoul, South Korea.
- Research and Development Department, VISUWORKS, Seoul, South Korea.
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Cozzupoli GM, Fasciani R, Fedeli R, Rizzo S. Association of torpedo maculopathy and keratoconus in a young patient: A multimodal imaging study. Eur J Ophthalmol 2024; 34:52-58. [PMID: 37844612 DOI: 10.1177/11206721231207663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
PURPOSE To report and document a case of torpedo maculopathy found in a patient affected by keratoconus.Case report: An healthy 16-year-old male patient, affected by keratoconus in both eyes, was referred to the cornea service of our hospital for a follow-up visit.During the dilated fundus examination of the left eye, an oval, well-demarcated, hypopigmented lesion was observed in the juxtafoveal temporal region, pointing towards the center of the macula. Multimodal imaging of the lesion was performed, and the diagnosis of Torpedo Maculopathy was established based on the clinical picture. CONCLUSION This is the first case of torpedo maculopathy described in a patient affected by keratoconus. This association may be merely fortuitous or the result of developmental abnormalities affecting both corneal and retinal structures.
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Affiliation(s)
| | - Romina Fasciani
- Ophthalmology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italia
- Università Cattolica del Sacro Cuore, Rome, Italia
| | - Romolo Fedeli
- Ophthalmology Unit, Azienda Ospedaliera, Cardinale G. Panico, Tricase (Le), Italia
| | - Stanislao Rizzo
- Ophthalmology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italia
- Università Cattolica del Sacro Cuore, Rome, Italia
- Consiglio Nazionale delle Ricerche, Istituto di Neuroscienze, Pisa, Italia
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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] [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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Pinheiro-Costa J, Ribeiro M, Moura R, Madeira D, Falcão-Reis F, Carneiro Â. Macular parameters with and without scleral contact lens in keratoconus using Spectralis optical coherence tomography. Clin Exp Optom 2023; 106:930-932. [PMID: 37914535 DOI: 10.1080/08164622.2022.2131376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 09/28/2022] [Indexed: 11/05/2022] Open
Affiliation(s)
- João Pinheiro-Costa
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
- Department of Biomedicine, University of Porto, Porto, Portugal
| | - Margarida Ribeiro
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
| | - Rodolfo Moura
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
| | - Dulce Madeira
- Department of Biomedicine, University of Porto, Porto, Portugal
| | - Fernando Falcão-Reis
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
- Department of Surgery and Physiology, University of Porto, Porto, Portugal
| | - Ângela Carneiro
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
- Department of Surgery and Physiology, University of Porto, Porto, Portugal
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Pinheiro-Costa J, Lima Fontes M, Luís C, Martins S, Soares R, Madeira D, Falcão-Reis F, Carneiro Â. Serum inflammatory biomarkers are associated with increased choroidal thickness in keratoconus. Sci Rep 2023; 13:10862. [PMID: 37407658 PMCID: PMC10322974 DOI: 10.1038/s41598-023-37472-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 06/22/2023] [Indexed: 07/07/2023] Open
Abstract
Inflammation may play a significant role in Keratoconus (KC), but the relationship between inflammatory markers and choroidal thickness (CT) is unknown. The purpose of this study was to evaluate serum inflammatory markers and correlate them with the choroidal profile of KC patients and control subjects. Forty patients with KC and 26 age-matched control subjects were enrolled in a cross-sectional case-control study. Choroidal profile was studied with a Spectralis Heidelberg apparatus and venous blood samples were collected. Neutrophil/lymphocyte ratio (NLR), monocyte/HDL ratio (MHR), platelet/lymphocyte ratio (PLR) and systemic immune inflammation index (SII) were calculated. Serum inflammatory biomarkers IL-1, IL-6 and TNF-alfa were also analyzed. KC group presented thicker choroids in each evaluated point when compared to the control group (subfoveal CT 417.38 ± 79.79 vs 299.61 ± 76.13, p < 0.001 for all measured locations). Mean values of NLR, PLR and SII were significantly higher in patients with KC (NLR p = 0.001; PLR p = 0.042; SII p = 0.007). Although KC patients presented higher mean levels of MHR, IL-1, IL-6 and TNF-α than control group, no significant differences were achieved. Positive correlations were found between subfoveal CT and NLR and SII (0.408, p = 0.001 and 0.288, p = 0.019 respectively). The results presented are in favor of a relationship between the increased CT and inflammatory mechanisms in KC patients. The elevated serum inflammatory indices NLR, SII and PLR provide additional evidence of a role for systemic inflammation in the pathophysiology of KC.
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Affiliation(s)
- João Pinheiro-Costa
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal.
- Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal.
| | - Mário Lima Fontes
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
- Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
| | - Carla Luís
- Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
- i3S - Institute of Research and Innovation in Health, University of Porto, Porto, Portugal
| | - Sandra Martins
- Department of Clinical Pathology, Centro Hospitalar Universitário São João, Porto, Portugal
- EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal
| | - Raquel Soares
- Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
- i3S - Institute of Research and Innovation in Health, University of Porto, Porto, Portugal
| | - Dulce Madeira
- Department of Biomedicine, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
- CINTESIS - Center for Health Technology and Services Research, Porto, Portugal
| | - Fernando Falcão-Reis
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Ângela Carneiro
- Department of Ophthalmology, Centro Hospitalar Universitário São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Porto, Portugal
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New Findings in Early-Stage Keratoconus: Lamina Cribrosa Curvature, Retinal Nerve Fiber Layer Thickness, and Vascular Perfusion. Am J Ophthalmol 2023; 246:122-129. [PMID: 36323392 DOI: 10.1016/j.ajo.2022.10.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 10/15/2022] [Accepted: 10/20/2022] [Indexed: 01/24/2023]
Abstract
PURPOSE Our aim was to investigate the involvement of posterior pole structures in eyes affected by keratoconus (KC). Optical coherence tomography (OCT) and OCT angiography (OCTA) were used to determine the status of lamina cribrosa (LC), peripapillary retinal nerve fiber layer (RNFL), macular and peripapillary microvasculature. DESIGN Observational, cross-sectional, case-control analysis. METHODS Single-center investigation involving patients with KC and healthy control subjects. Enrolled subjects underwent anterior segment OCT combined with Placido-disk topography, macular and optic nerve head swept-source OCT and swept-source OCTA scans, and 3D wide glaucoma module for peripapillary RNFL thickness measurement. The LC curvature index was used to express the degree of LC posterior bowing. We calculated the vessel density and vessel length density at the macular superficial capillary plexus, deep capillary plexus, choriocapillaris, and nerve radial peripapillary capillary plexus. RESULTS Overall, 32 eyes with KC and an equal number of age- and axial length-matched control eyes were included in the analysis. Almost all (97%) of eyes with KC were classified as early stage. KC displayed a reduction in peripapillary RNFL thickness (104.8 ± 11.9 µm vs 110.7 ± 10.5 µm; P = .039) and nerve radial peripapillary capillary plexus vessel density (46.31% ± 3% vs 43.82% ± 4%; P = .006) when compared with control subjects; these differences were more evident in the temporal sector and were associated with a higher LC curvature index (9.9% ± 2.6% vs 8.48% ± 1.7%; P = .012). Mean macular superficial capillary plexus vessel density was 3 percentage points lower in eyes with KC than in healthy controls (P < .001). CONCLUSION Early-stage KC may be characterized by a posterior bowing of the LC along with a subtle peripapillary RNFL thinning and vascular impairment. These findings support the hypothesis that KC may be a corneal manifestation of a more generalized "eye collagen disease."
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Ribeiro M, Barbosa C, Correia P, Torrão L, Neves Cardoso P, Moreira R, Falcão-Reis F, Falcão M, Pinheiro-Costa J. Best Fit Sphere Back and Adjusted Maximum Elevation of Corneal Back Surface as Novel Predictors of Keratoconus Progression. Clin Ophthalmol 2022; 16:4239-4248. [PMID: 36573232 PMCID: PMC9789719 DOI: 10.2147/opth.s388614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 12/06/2022] [Indexed: 12/30/2022] Open
Abstract
Purpose We evaluated the Maximum Elevation of Corneal Back Surface adjusted to the same Best Fit Sphere Back (BFSB) between timeline measurements (AdjEleBmax) and the BFSB radius (BFSBR) itself as new tomographic parameters for documentation of ectasia progression and compare them with the most recent and reliable parameters used on keratoconus (KC) progression. Results We evaluated the performance and the ideal cutoff point of Kmax, D-index, posterior radius of curvature from the 3.0 mm centered on the thinnest point (PRC), EleBmax, BFSBR, and AdjEleBmax as isolated parameters to document KC progression (defined as a significant change in two or more variables), we found a sensitivity of 70%, 82%, 79%, 65%, 51%, and 63% and a specificity of 91%, 98%, 80%, 73%, 80%, and 84% to detect KC progression. The area under the curve (AUC) for each variable was 0.822, 0.927, 0.844, 0.690, 0.695, 0.754, respectively. Conclusion AdjEleBmax presented a greater specificity, larger AUC, and better performance compared to EleBmax without any adjustment, with similar sensitivity. Although AdjEleBmax and BFSB demonstrated smaller AUC and specificities comparing with Kmax and D-Index, AdjEleBmax still presented a good performance with a reasonable AUC. Since the shape of the posterior surface, more aspheric and curved than the anterior, may facilitate detection of change, we suggest the inclusion of AdjEleBmax in the evaluation of KC progression in conjunction with other variables to increase the reliability of our clinical evaluation and early detection of progression.
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Affiliation(s)
- Margarida Ribeiro
- Department of Ophthalmology, Centro Hospitalar e Universitário São João, Porto, Portugal,Department of Biomedicine – Faculty of Medicine of Porto University, Porto, Portugal,Correspondence: Margarida Ribeiro, Department of Ophthalmology, Centro Hospitalar e Universitário São João, Alameda Prof. Hernâni Monteiro Porto, 4200-319, Portugal, Email
| | | | - Paulo Correia
- Faculty of Medicine of Porto University, Porto, Portugal
| | - Luís Torrão
- Department of Ophthalmology, Centro Hospitalar e Universitário São João, Porto, Portugal
| | - Pedro Neves Cardoso
- Department of Ophthalmology, Centro Hospitalar e Universitário São João, Porto, Portugal
| | - Raúl Moreira
- Department of Ophthalmology, Centro Hospitalar e Universitário São João, Porto, Portugal
| | - Fernando Falcão-Reis
- Department of Ophthalmology, Centro Hospitalar e Universitário São João, Porto, Portugal,Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - Manuel Falcão
- Department of Ophthalmology, Centro Hospitalar e Universitário São João, Porto, Portugal,Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - João Pinheiro-Costa
- Department of Ophthalmology, Centro Hospitalar e Universitário São João, Porto, Portugal,Department of Biomedicine – Faculty of Medicine of Porto University, Porto, Portugal
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15
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McMonnies CW. Mechanisms of corneal trauma in response to rubbing and other intraocular pressure elevating activities in keratoconus. EXPERT REVIEW OF OPHTHALMOLOGY 2022. [DOI: 10.1080/17469899.2022.2153119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Charles W McMonnies
- Faculty of Medicine and Health, School of Optometry and Vision Science, University of New South Wales
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Hashemi H, Heirani M, Ambrosio R, Hafezi F, Naroo SA, Khorrami-Nejad M. Reply to the letter-to-the-editor. Ocul Surf 2022; 25:71. [PMID: 35568372 DOI: 10.1016/j.jtos.2022.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 11/16/2022]
Affiliation(s)
- Hassan Hashemi
- Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran
| | - Mohsen Heirani
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
| | - Renato Ambrosio
- Department of Ophthalmology, Federal University of the State of Rio de Janeiro, Brazil
| | - Farhad Hafezi
- ELZA Institute, Dietikon, Zurich, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Shehzad A Naroo
- College of Health and Life Sciences, Aston University, Birmingham, B4 7ET, UK
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Morphological retinal changes in keratoconus. Ocul Surf 2022; 25:75. [DOI: 10.1016/j.jtos.2022.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 05/05/2022] [Indexed: 11/17/2022]
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