1
|
Neil GJ, Kluttig KH, Allison WT. Determining Photoreceptor Cell Identity: Rod Versus Cone Fate Governed by tbx2b Opposing nrl. Invest Ophthalmol Vis Sci 2024; 65:39. [PMID: 38261312 PMCID: PMC10810017 DOI: 10.1167/iovs.65.1.39] [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: 09/22/2023] [Accepted: 12/28/2023] [Indexed: 01/24/2024] Open
Abstract
Purpose NRL is an influential transcription factor and central to animal modeling in ophthalmology. Disrupting NRL abrogates rod development and produces an excess of S-cones (also known as "UV cones" or "short-wavelength-sensitive1 [SWS1] cones"). Strikingly, mutations in zebrafish tbx2b produce the exact opposite phenotypes (excess rods and loss of SWS1 cones). We sought to define what genetic relationship exists, if any, between these transcription factors. We also infer whether these two phenotypes (altered rod abundance and altered SWS1 cone abundance) are independent versus inter-related. Methods Zebrafish mutants were bred to disrupt nrl and tbx2b in concert. Rods and SWS1 cones were quantified and characterized at ultrastructural and transcriptional levels. Results Considering single mutant zebrafish, we confirmed previously established phenotypes and noted that the number of rods lost in nrl-/- mutants is reflected by a concomitant increase in SWS1 cone abundance. The tbx2b-/- mutants present the opposite phenotype(s) but exhibit a similar trade-off in cell abundances, with lots of rods and a concomitant decrease in SWS1 cones. Double mutant nrl-/-;tbx2b-/- zebrafish recapitulate the nrl-/- mutant phenotype(s). Conclusions The tbx2b is thought to be required for producing SWS1 cones in zebrafish, but this can be over-ridden when nrl is absent. Regarding the altered cell abundances observed in either tbx2b-/- or nrl-/- mutants, the alterations in rod and SWS1 cones appear to not be two separate phenotypes but are instead a single intertwined outcome. The tbx2b and nrl are in an epistatic relationship, with nrl phenotypes dominating, implying that tbx2b is upstream of nrl in photoreceptor cell fate determination.
Collapse
Affiliation(s)
- Gavin J. Neil
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Kaitlyn H. Kluttig
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - W. Ted Allison
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Department of Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
2
|
Bellucci C, Romano A, Ramanzini F, Tedesco SA, Gandolfi S, Mora P. Pars Plana Vitrectomy Alone or Combined with Phacoemulsification to Treat Rhegmatogenous Retinal Detachment: A Systematic Review of the Recent Literature. J Clin Med 2023; 12:5021. [PMID: 37568424 PMCID: PMC10420090 DOI: 10.3390/jcm12155021] [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: 06/13/2023] [Revised: 07/22/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023] Open
Abstract
Pars plana vitrectomy is today a common first-line procedure for treatment of rhegmatogenous retinal detachment (RRD). Removal or preservation of the natural lens at the time of vitrectomy is associated with both advantages and disadvantages. The combination of cataract extraction (i.e., phacoemulsification) with pars plana vitrectomy (PPVc) enhances visualization of the peripheral retina and the surgical management of the vitreous base. However, PPVc prolongs the surgical time and is associated with iatrogenic loss of the accommodation function in younger patients, possible postoperative anisometropia, and unexpected refractive results. Performance of pars plana vitrectomy alone (PPVa) requires good technical skills to minimize the risk of lens damage, and quickens cataract development. We retrieved all recent papers that directly compared PPVc and PPVa using parameters that we consider essential when choosing between the two procedures (the success rate of anatomical RRD repair, postoperative refractive error, intra- and postoperative complications, and costs). PPVa and PPVc were generally comparable in terms of RRD anatomical repair. PPVc was associated with fewer intraoperative, but more postoperative, complications. Macula-off RRD PPVc treatment was often associated with undesirable myopic refractive error. PPVa followed by phacoemulsification was the most expensive procedure.
Collapse
Affiliation(s)
| | | | | | | | | | - Paolo Mora
- Ophthalmology Unit, University Hospital of Parma, 43126 Parma, Italy
| |
Collapse
|
3
|
Wang Y, Wong J, Duncan JL, Roorda A, Tuten WS. Enhanced S-Cone Syndrome: Elevated Cone Counts Confer Supernormal Visual Acuity in the S-Cone Pathway. Invest Ophthalmol Vis Sci 2023; 64:17. [PMID: 37459066 PMCID: PMC10362924 DOI: 10.1167/iovs.64.10.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023] Open
Abstract
Purpose To measure photoreceptor packing density and S-cone spatial resolution as a function of retinal eccentricity in patients with enhanced S-cone syndrome (ESCS) and to discuss the possible mechanisms supporting their supernormal S-cone acuity. Methods We used an adaptive optics scanning laser ophthalmoscope (AOSLO) to characterize photoreceptor packing. A custom non-AO display channel was used to measure L/M- and S-cone-mediated visual acuity during AOSLO imaging. Acuity measurements were obtained using a four-alternative, forced-choice, tumbling E paradigm along the temporal meridian between the fovea and 4° eccentricity in five of six patients and in seven control subjects. L/M acuity was tested by presenting long-pass-filtered optotypes on a black background, excluding wavelengths to which S-cones are sensitive. S-cone isolation was achieved using a two-color, blue-on-yellow chromatic adaptation method that was validated on three control subjects. Results Inter-cone spacing measurements revealed a near-uniform cone density profile (ranging from 0.9-1.5 arcmin spacing) throughout the macula in ESCS. For comparison, normal cone density decreases by a factor of 14 from the fovea to 6°. Cone spacing of ESCS subjects was higher than normal in the fovea and subnormal beyond 2°. Compared to the control subjects (n = 7), S-cone-mediated acuities in patients with ESCS were normal near the fovea and became increasingly supernormal with retinal eccentricity. Beyond 2°, S-cone acuities were superior to L/M-cone-mediated acuity in the ESCS cohort, a reversal of the trend observed in normal retinas. Conclusions Higher than normal parafoveal cone densities (presumably dominated by S-cones) confer better than normal S-cone-mediated acuity in ESCS subjects.
Collapse
Affiliation(s)
- Yiyi Wang
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| | - Jessica Wong
- Department of Ophthalmology, University of California, San Francisco, California, United States
| | - Jacque L Duncan
- Department of Ophthalmology, University of California, San Francisco, California, United States
| | - Austin Roorda
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| | - William S Tuten
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, California, United States
| |
Collapse
|
4
|
Toms M, Ward N, Moosajee M. Nuclear Receptor Subfamily 2 Group E Member 3 (NR2E3): Role in Retinal Development and Disease. Genes (Basel) 2023; 14:1325. [PMID: 37510230 PMCID: PMC10379133 DOI: 10.3390/genes14071325] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/11/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023] Open
Abstract
NR2E3 is a nuclear hormone receptor gene required for the correct development of the retinal rod photoreceptors. Expression of NR2E3 protein in rod cell precursors suppresses cone-specific gene expression and, in concert with other transcription factors including NRL, activates the expression of rod-specific genes. Pathogenic variants involving NR2E3 cause a spectrum of retinopathies, including enhanced S-cone syndrome, Goldmann-Favre syndrome, retinitis pigmentosa, and clumped pigmentary retinal degeneration, with limited evidence of genotype-phenotype correlations. A common feature of NR2E3-related disease is an abnormally high number of cone photoreceptors that are sensitive to short wavelength light, the S-cones. This characteristic has been supported by mouse studies, which have also revealed that loss of Nr2e3 function causes photoreceptors to develop as cells that are intermediate between rods and cones. While there is currently no available cure for NR2E3-related retinopathies, there are a number of emerging therapeutic strategies under investigation, including the use of viral gene therapy and gene editing, that have shown promise for the future treatment of patients with NR2E3 variants and other inherited retinal diseases. This review provides a detailed overview of the current understanding of the role of NR2E3 in normal development and disease, and the associated clinical phenotypes, animal models, and therapeutic studies.
Collapse
Affiliation(s)
- Maria Toms
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Ocular Genomics and Therapeutics, The Francis Crick Institute, London NW1 1AT, UK
| | - Natasha Ward
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Mariya Moosajee
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Ocular Genomics and Therapeutics, The Francis Crick Institute, London NW1 1AT, UK
- Department of Genetics, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
- Department of Ophthalmology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| |
Collapse
|
5
|
Sun C, Chen S. Disease-causing mutations in genes encoding transcription factors critical for photoreceptor development. Front Mol Neurosci 2023; 16:1134839. [PMID: 37181651 PMCID: PMC10172487 DOI: 10.3389/fnmol.2023.1134839] [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: 12/30/2022] [Accepted: 04/04/2023] [Indexed: 05/16/2023] Open
Abstract
Photoreceptor development of the vertebrate visual system is controlled by a complex transcription regulatory network. OTX2 is expressed in the mitotic retinal progenitor cells (RPCs) and controls photoreceptor genesis. CRX that is activated by OTX2 is expressed in photoreceptor precursors after cell cycle exit. NEUROD1 is also present in photoreceptor precursors that are ready to specify into rod and cone photoreceptor subtypes. NRL is required for the rod fate and regulates downstream rod-specific genes including the orphan nuclear receptor NR2E3 which further activates rod-specific genes and simultaneously represses cone-specific genes. Cone subtype specification is also regulated by the interplay of several transcription factors such as THRB and RXRG. Mutations in these key transcription factors are responsible for ocular defects at birth such as microphthalmia and inherited photoreceptor diseases such as Leber congenital amaurosis (LCA), retinitis pigmentosa (RP) and allied dystrophies. In particular, many mutations are inherited in an autosomal dominant fashion, including the majority of missense mutations in CRX and NRL. In this review, we describe the spectrum of photoreceptor defects that are associated with mutations in the above-mentioned transcription factors, and summarize the current knowledge of molecular mechanisms underlying the pathogenic mutations. At last, we deliberate the outstanding gaps in our understanding of the genotype-phenotype correlations and outline avenues for future research of the treatment strategies.
Collapse
Affiliation(s)
- Chi Sun
- Department of Ophthalmology and Visual Sciences, Washington University in St. Louis, St. Louis, MO, United States
- *Correspondence: Chi Sun,
| | - Shiming Chen
- Department of Ophthalmology and Visual Sciences, Washington University in St. Louis, St. Louis, MO, United States
- Department of Developmental Biology, Washington University in St. Louis, St. Louis, MO, United States
| |
Collapse
|
6
|
Ammar MJ, Scavelli KT, Uyhazi KE, Bedoukian EC, Serrano LW, Edelstein ID, Vergilio G, Cooper RF, Morgan JIW, Kumar P, Aleman TS. ENHANCED S-CONE SYNDROME: VISUAL FUNCTION, CROSS-SECTIONAL IMAGING, AND CELLULAR STRUCTURE WITH ADAPTIVE OPTICS OPHTHALMOSCOPY. Retin Cases Brief Rep 2021; 15:694-701. [PMID: 31306293 PMCID: PMC6980308 DOI: 10.1097/icb.0000000000000891] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To describe in detail the phenotype of a patient with enhanced S-cone syndrome. METHODS We describe a 13-year-old boy who presented with blurred vision, vitreous cells, cystoid macular edema refractory to steroid treatment, and a negative uveitic workup. The patient underwent a complete ophthalmic examination, full-field electroretinograms (ffERG), automatic static perimetry and multimodal imaging with spectral domain optical coherence tomography, and adaptive optics scanning laser ophthalmoscopy (AOSLO). RESULTS Spectral domain optical coherence tomography demonstrated cystoid macular edema and a hyperthick, delaminated midperipheral retina. Fluorescein angiography did not demonstrate macular leakage. Rod-mediated ffERGs were undetectable, and there was a supernormal response to short-wavelength stimuli compared with photopically matched longer wavelengths of light consistent with enhanced S-cone syndrome. Gene screening was positive for compound heterozygous mutations NR2E3: a known (c.119-2 A>C) and a novel (c.119-1G>A) mutation. By perimetry, sensitivities were normal or above normal for short-wavelength stimuli; there was no detectable rod-mediated vision. AOSLO demonstrated higher than normal cone densities in the perifoveal retina and evidence for smaller outer segment cone diameters. CONCLUSION Evidence for supernumerary cones (at least twice the normal complement) by AOSLO and spectral domain optical coherence tomography was associated with supernormal S-cone sensitivities and electroretinogram responses confirming previous in vivo findings in postmortem human specimens. Smaller than normal cones in enhanced S-cone syndrome may represent "hybrid" photoreceptors analogous to the rd7/rd7 murine model of the disease.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Jessica I. W. Morgan
- Scheie Eye Institute
- the Center for Advanced Retinal and Ocular Therapeutics (CAROT), Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Tomas S. Aleman
- Scheie Eye Institute
- The Children’s Hospital of Philadelphia
- the Center for Advanced Retinal and Ocular Therapeutics (CAROT), Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| |
Collapse
|
7
|
Green Sanderson K, Stephenson KAJ, Dockery A, Keegan DJ. Pigmentary retinopathy masked by asymmetric acquired phenomena. BMJ Case Rep 2021; 14:e246982. [PMID: 34725069 PMCID: PMC8562530 DOI: 10.1136/bcr-2021-246982] [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] [Accepted: 10/15/2021] [Indexed: 11/03/2022] Open
Affiliation(s)
- Kit Green Sanderson
- School of Medicine, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin, Ireland
| | - Kirk A J Stephenson
- Ophthalmology Department, Mater Misericordiae University Hospital, Dublin, Ireland
| | - Adrian Dockery
- Ophthalmology Department, Mater Misericordiae University Hospital, Dublin, Ireland
| | - David J Keegan
- Ophthalmology Department, Mater Misericordiae University Hospital, Dublin, Ireland
| |
Collapse
|
8
|
Mora P, Favilla S, Calzetti G, Berselli G, Benatti L, Carta A, Gandolfi S, Tedesco SA. Parsplana vitrectomy alone versus parsplana vitrectomy combined with phacoemulsification for the treatment of rhegmatogenous retinal detachment: a randomized study. BMC Ophthalmol 2021; 21:196. [PMID: 33941122 PMCID: PMC8091481 DOI: 10.1186/s12886-021-01954-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 04/20/2021] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND To compare parsplana vitrectomy (PPV) with and without phacoemulsification to treat rhegmatogenous retinal detachment (RRD). METHODS Subjects aged 48-65 years with RRD in a phakic eye due to superior retinal tears with an overall extension of retinal breaks < 90° underwent to PPV alone (group A); or PPV plus phacoemulsification (phacovitrectomy, PCV, group B). Post-operative follow-up visits occurred at 1 week, 1 month (m1), 3 months (m3), and 6 months (m6) after surgery. The main outcome was the rate of retinal reattachment. Secondary outcomes included best-corrected visual acuity (BCVA), intraocular pressure (IOP), central macular thickness (CMT), and cataract progression (in the lens-sparing [PPV-alone] group). RESULTS In this initial phase of the study a total of 59 patients (mean age: 55 years, 59 eyes) were enrolled: 29 eyes in group A and 30 eyes in group B. Both groups had similar gas tamponade. During the follow-up there were three cases of RRD recurrence in group A and one in group B. The relative risk of recurrence in group A was 3.22 times higher but the difference was not significant (p = 0.3). The two groups were also similar in terms of BCVA and IOP variation. At m3, CMT was significantly higher in group B (p = 0.014). In group A, cataract progression was significant at m6 (p = 0.003). CONCLUSIONS In a cohort of RRD patients selected according to their preoperative clinical characteristics, PPV was comparable to PCV in terms of the rate of retinal reattachment after 6 months. TRIAL REGISTRATION ISRCTN15940019 . Date registered: 15/01/2021 (retrospectively registered).
Collapse
Affiliation(s)
- Paolo Mora
- Ophthalmology Unit, Department of Medicine and Surgery, University Hospital of Parma, via Gramsci 14, 43126, Parma, Italy.
| | - Stefania Favilla
- Independent Researcher, on behalf of the University of Parma, Parma, Italy
| | - Giacomo Calzetti
- Ophthalmology Unit, Department of Medicine and Surgery, University Hospital of Parma, via Gramsci 14, 43126, Parma, Italy
- Institute of Molecular and Clinical Ophthalmology Basel, Basel, Switzerland
| | - Giulia Berselli
- Ophthalmology Unit, Department of Medicine and Surgery, University Hospital of Parma, via Gramsci 14, 43126, Parma, Italy
| | - Lucia Benatti
- Ophthalmology Unit, Department of Medicine and Surgery, University Hospital of Parma, via Gramsci 14, 43126, Parma, Italy
| | - Arturo Carta
- Ophthalmology Unit, Department of Medicine and Surgery, University Hospital of Parma, via Gramsci 14, 43126, Parma, Italy
| | - Stefano Gandolfi
- Ophthalmology Unit, Department of Medicine and Surgery, University Hospital of Parma, via Gramsci 14, 43126, Parma, Italy
| | - Salvatore A Tedesco
- Ophthalmology Unit, Department of Medicine and Surgery, University Hospital of Parma, via Gramsci 14, 43126, Parma, Italy
| |
Collapse
|
9
|
Iannaccone A, Brabbit E, Lopez-Miro C, Love Z, Griffiths V, Kedrov M, Haider NB. Interspecies Correlations between Human and Mouse NR2E3-Associated Recessive Disease. J Clin Med 2021; 10:jcm10030475. [PMID: 33513943 PMCID: PMC7865474 DOI: 10.3390/jcm10030475] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/13/2021] [Accepted: 01/18/2021] [Indexed: 11/16/2022] Open
Abstract
NR2E3-associated recessive disease in humans is historically defined by congenital night blinding retinopathy, characterized by an initial increase in short-wavelength (S)-cone sensitivity and progressive loss of rod and cone function. The retinal degeneration 7 (rd7) murine model, harboring a recessive mutation in the mouse ortholog of NR2E3, has been a well-studied disease model and recently evaluated as a therapeutic model for NR2E3-associated retinal degenerations. This study aims to draw parallels between human and mouse NR2E3-related disease through examination of spectral domain optical coherence tomography (SD-OCT) imaging between different stage of human disease and its murine counterpart. We propose that SD-OCT is a useful non-invasive diagnostic tool to compare human clinical dystrophy presentation with that of the rd7 mouse and make inference that may be of therapeutically relevance. Additionally, a longitudinal assessment of rd7 disease progression, utilizing available clinical data from our patients as well as extensive retrospective analysis of visual acuity data from published cases of human NR2E3-related disease, was curated to identify further valuable correlates between human and mouse Nr2e3 disease. Results of this study validate the slow progression of NR2E3-associated disease in humans and the rd7 mice and identify SD-OCT characteristics in patients at or near the vascular arcades that correlate well with the whorls and rosettes that are seen also in the rd7 mouse and point to imaging features that appear to be associated with better preserved S-cone mediated retinal function. The correlation of histological findings between rd7 mice and human imaging provides a solid foundation for diagnostic use of pathophysiological and prognostic information to further define characteristics and a relevant timeline for therapeutic intervention in the field of NR2E3-associated retinopathies.
Collapse
Affiliation(s)
- Alessandro Iannaccone
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
- Correspondence: (A.I.); (N.B.H.)
| | - Emily Brabbit
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA; (E.B.); (Z.L.)
| | - Christiaan Lopez-Miro
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
| | - Zoe Love
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA; (E.B.); (Z.L.)
| | - Victoria Griffiths
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
| | - Marina Kedrov
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
| | - Neena B. Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA; (E.B.); (Z.L.)
- Correspondence: (A.I.); (N.B.H.)
| |
Collapse
|
10
|
Garafalo AV, Sheplock R, Sumaroka A, Roman AJ, Cideciyan AV, Jacobson SG. Childhood-onset genetic cone-rod photoreceptor diseases and underlying pathobiology. EBioMedicine 2021; 63:103200. [PMID: 33421946 PMCID: PMC7806809 DOI: 10.1016/j.ebiom.2020.103200] [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: 10/21/2020] [Revised: 12/01/2020] [Accepted: 12/17/2020] [Indexed: 12/27/2022] Open
Abstract
Inherited retinal diseases (IRDs) were first classified clinically by history, ophthalmoscopic appearance, type of visual field defects, and electroretinography (ERG). ERGs isolating the two major photoreceptor types (rods and cones) showed some IRDs with greater cone than rod retinal dysfunction; others were the opposite. Within the cone-rod diseases, there can be phenotypic variability, which can be attributed to genetic heterogeneity and the variety of visual function mechanisms that are disrupted. Most cause symptoms from childhood or adolescence, although others can manifest later in life. Among the causative genes for cone-rod dystrophy (CORD) are those encoding molecules in phototransduction cascade activation and recovery processes, photoreceptor outer segment structure, the visual cycle and photoreceptor development. We review 11 genes known to cause cone-rod disease in the context of their roles in normal visual function and retinal structure. Knowledge of the pathobiology of these genetic diseases is beginning to pave paths to therapy.
Collapse
Affiliation(s)
- Alexandra V Garafalo
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rebecca Sheplock
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alexander Sumaroka
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alejandro J Roman
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Artur V Cideciyan
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Samuel G Jacobson
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
11
|
Otsuka Y, Oishi A, Miyata M, Oishi M, Hasegawa T, Numa S, Ikeda HO, Tsujikawa A. Wavelength of light and photophobia in inherited retinal dystrophy. Sci Rep 2020; 10:14798. [PMID: 32908200 PMCID: PMC7481180 DOI: 10.1038/s41598-020-71707-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 08/13/2020] [Indexed: 11/16/2022] Open
Abstract
Inherited retinal dystrophy (IRD) patients often experience photophobia. However, its mechanism has not been elucidated. This study aimed to investigate the main wavelength of light causing photophobia in IRD and difference among patients with different phenotypes. Forty-seven retinitis pigmentosa (RP) and 22 cone-rod dystrophy (CRD) patients were prospectively recruited. We designed two tinted glasses: short wavelength filtering (SWF) glasses and middle wavelength filtering (MWF) glasses. We classified photophobia into three types: (A) white out, (B) bright glare, and (C) ocular pain. Patients were asked to assign scores between one (not at all) and five (totally applicable) for each symptom with and without glasses. In patients with RP, photophobia was better relieved with SWF glasses {“white out” (p < 0.01) and “ocular pain” (p = 0.013)}. In CRD patients, there was no significant difference in the improvement wearing two glasses (p = 0.247–1.0). All RP patients who preferred MWF glasses had Bull’s eye maculopathy. Meanwhile, only 15% of patients who preferred SWF glasses had the finding (p < 0.001). Photophobia is primarily caused by short wavelength light in many patients with IRD. However, the wavelength responsible for photophobia vary depending on the disease and probably vary according to the pathological condition.
Collapse
Affiliation(s)
- Yuki Otsuka
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Akio Oishi
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan. .,Department of Ophthalmology and Visual Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan.
| | - Manabu Miyata
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Maho Oishi
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Tomoko Hasegawa
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Shogo Numa
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Hanako Ohashi Ikeda
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Akitaka Tsujikawa
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| |
Collapse
|
12
|
Rod function deficit in retained photoreceptors of patients with class B Rhodopsin mutations. Sci Rep 2020; 10:12552. [PMID: 32724127 PMCID: PMC7387454 DOI: 10.1038/s41598-020-69456-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 07/09/2020] [Indexed: 12/27/2022] Open
Abstract
A common inherited retinal disease is caused by mutations in RHO expressed in rod photoreceptors that provide vision in dim ambient light. Approximately half of all RHO mutations result in a Class B phenotype where mutant rods are retained in some retinal regions but show severe degeneration in other regions. We determined the natural history of dysfunction and degeneration of retained rods by serially evaluating patients. Even when followed for more than 20 years, rod function and structure at some retinal locations could remain unchanged. Other locations showed loss of both vision and photoreceptors but the rate of rod vision loss was greater than the rate of photoreceptor degeneration. This unexpected divergence in rates with disease progression implied the development of a rod function deficit beyond loss of cells. The divergence of progression rates was also detectable over a short interval of 2 years near the health-disease transition in the superior retina. A model of structure–function relationship supported the existence of a large rod function deficit which was also most prominent near regions of health-disease transition. Our studies support the realistic therapeutic goal of improved night vision for retinal regions specifically preselected for rod function deficit in patients.
Collapse
|
13
|
Roman AJ, Powers CA, Semenov EP, Sheplock R, Aksianiuk V, Russell RC, Sumaroka A, Garafalo AV, Cideciyan AV, Jacobson SG. Short-Wavelength Sensitive Cone (S-cone) Testing as an Outcome Measure for NR2E3 Clinical Treatment Trials. Int J Mol Sci 2019; 20:ijms20102497. [PMID: 31117170 PMCID: PMC6566804 DOI: 10.3390/ijms20102497] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/08/2019] [Accepted: 05/17/2019] [Indexed: 11/16/2022] Open
Abstract
Recessively-inherited NR2E3 gene mutations cause an unusual retinopathy with abnormally-increased short-wavelength sensitive cone (S-cone) function, in addition to reduced rod and long/middle-wavelength sensitive cone (L/M-cone) function. Progress toward clinical trials to treat patients with this otherwise incurable retinal degeneration prompted the need to determine efficacy outcome measures. Comparisons were made between three computerized perimeters available in the clinic. These perimeters could deliver short-wavelength stimuli on longer-wavelength adapting backgrounds to measure whether S-cone vision can be quantified. Results from a cohort of normal subjects were compared across the three perimeters to determine S-cone isolation and test-retest variability. S-cone perimetry data from NR2E3-ESCS (enhanced S-cone syndrome) patients were examined and determined to have five stages of disease severity. Using these stages, strategies were proposed for monitoring efficacy of either a focal or retina-wide intervention. This work sets the stage for clinical trials.
Collapse
Affiliation(s)
- Alejandro J Roman
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Christian A Powers
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Evelyn P Semenov
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Rebecca Sheplock
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Valeryia Aksianiuk
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Robert C Russell
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Alexander Sumaroka
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Alexandra V Garafalo
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Artur V Cideciyan
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| | - Samuel G Jacobson
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA 19104, USA.
| |
Collapse
|
14
|
Garnai SJ, Brinkmeier ML, Emery B, Aleman TS, Pyle LC, Veleva-Rotse B, Sisk RA, Rozsa FW, Ozel AB, Li JZ, Moroi SE, Archer SM, Lin CM, Sheskey S, Wiinikka-Buesser L, Eadie J, Urquhart JE, Black GC, Othman MI, Boehnke M, Sullivan SA, Skuta GL, Pawar HS, Katz AE, Huryn LA, Hufnagel RB, Camper SA, Richards JE, Prasov L. Variants in myelin regulatory factor (MYRF) cause autosomal dominant and syndromic nanophthalmos in humans and retinal degeneration in mice. PLoS Genet 2019; 15:e1008130. [PMID: 31048900 PMCID: PMC6527243 DOI: 10.1371/journal.pgen.1008130] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 05/20/2019] [Accepted: 04/09/2019] [Indexed: 01/11/2023] Open
Abstract
Nanophthalmos is a rare, potentially devastating eye condition characterized by small eyes with relatively normal anatomy, a high hyperopic refractive error, and frequent association with angle closure glaucoma and vision loss. The condition constitutes the extreme of hyperopia or farsightedness, a common refractive error that is associated with strabismus and amblyopia in children. NNO1 was the first mapped nanophthalmos locus. We used combined pooled exome sequencing and strong linkage data in the large family used to map this locus to identify a canonical splice site alteration upstream of the last exon of the gene encoding myelin regulatory factor (MYRF c.3376-1G>A), a membrane bound transcription factor that undergoes autoproteolytic cleavage for nuclear localization. This variant produced a stable RNA transcript, leading to a frameshift mutation p.Gly1126Valfs*31 in the C-terminus of the protein. In addition, we identified an early truncating MYRF frameshift mutation, c.769dupC (p.S264QfsX74), in a patient with extreme axial hyperopia and syndromic features. Myrf conditional knockout mice (CKO) developed depigmentation of the retinal pigment epithelium (RPE) and retinal degeneration supporting a role of this gene in retinal and RPE development. Furthermore, we demonstrated the reduced expression of Tmem98, another known nanophthalmos gene, in Myrf CKO mice, and the physical interaction of MYRF with TMEM98. Our study establishes MYRF as a nanophthalmos gene and uncovers a new pathway for eye growth and development.
Collapse
Affiliation(s)
- Sarah J. Garnai
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
- Harvard Medical School, Boston, MA, United States of America
| | - Michelle L. Brinkmeier
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, United States of America
| | - Ben Emery
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States of America
| | - Tomas S. Aleman
- The Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
- Scheie Eye Institute, Department of Ophthalmology, Philadelphia, PA, United States of America
| | - Louise C. Pyle
- Division of Human Genetics, Children’s Hospital of Philadelphia, Philadelphia, PA, United States of America
| | - Biliana Veleva-Rotse
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States of America
| | - Robert A. Sisk
- Cincinnati Eye Institute, Cincinnati, Ohio, United States of America
| | - Frank W. Rozsa
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
- Molecular and Behavior Neuroscience Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Ayse Bilge Ozel
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, United States of America
| | - Jun Z. Li
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, United States of America
| | - Sayoko E. Moroi
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - Steven M. Archer
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - Cheng-mao Lin
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - Sarah Sheskey
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - Laurel Wiinikka-Buesser
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - James Eadie
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - Jill E. Urquhart
- Manchester Centre for Genomic Medicine, Manchester Academic Health Sciences Centre, Manchester University NHS Foundation Trust, St Mary’s Hospital, Manchester, United Kingdom
- Division of Evolution and Genomic Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Graeme C.M. Black
- Manchester Centre for Genomic Medicine, Manchester Academic Health Sciences Centre, Manchester University NHS Foundation Trust, St Mary’s Hospital, Manchester, United Kingdom
- Division of Evolution and Genomic Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Mohammad I. Othman
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - Michael Boehnke
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan, Ann Arbor, MI, United States of America
| | - Scot A. Sullivan
- Dean McGee Eye Institute, Department of Ophthalmology, University of Oklahoma, Oklahoma City, OK
| | - Gregory L. Skuta
- Dean McGee Eye Institute, Department of Ophthalmology, University of Oklahoma, Oklahoma City, OK
| | - Hemant S. Pawar
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
| | - Alexander E. Katz
- Medical Genomics and Metabolic Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States of America
| | - Laryssa A. Huryn
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, United States of America
| | - Robert B. Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, United States of America
| | | | - Sally A. Camper
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, United States of America
| | - Julia E. Richards
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
- Department of Epidemiology, University of Michigan, Ann Arbor, MI, United States of America
| | - Lev Prasov
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States of America
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, United States of America
| |
Collapse
|
15
|
Correction of NR2E3 Associated Enhanced S-cone Syndrome Patient-specific iPSCs using CRISPR-Cas9. Genes (Basel) 2019; 10:genes10040278. [PMID: 30959774 PMCID: PMC6523438 DOI: 10.3390/genes10040278] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 12/24/2022] Open
Abstract
Enhanced S-cone syndrome (ESCS) is caused by recessive mutations in the photoreceptor cell transcription factor NR2E3. Loss of NR2E3 is characterized by repression of rod photoreceptor cell gene expression, over-expansion of the S-cone photoreceptor cell population, and varying degrees of M- and L-cone photoreceptor cell development. In this study, we developed a CRISPR-based homology-directed repair strategy and corrected two different disease-causing NR2E3 mutations in patient-derived induced pluripotent stem cells (iPSCs) generated from two affected individuals. In addition, one patient’s iPSCs were differentiated into retinal cells and NR2E3 transcription was evaluated in CRISPR corrected and uncorrected clones. The patient’s c.119-2A>C mutation caused the inclusion of a portion of intron 1, the creation of a frame shift, and generation of a premature stop codon. In summary, we used a single set of CRISPR reagents to correct different mutations in iPSCs generated from two individuals with ESCS. In doing so we demonstrate the advantage of using retinal cells derived from affected patients over artificial in vitro model systems when attempting to demonstrate pathophysiologic mechanisms of specific mutations.
Collapse
|
16
|
Naik A, Ratra D, Banerjee A, Dalan D, Jandyal S, Rao G, Sen P, Bhende M, Jayaprakash V, Susvar P, Walinjkar J, Rao C. Enhanced S-cone syndrome: Clinical spectrum in Indian population. Indian J Ophthalmol 2019; 67:523-529. [PMID: 30900587 PMCID: PMC6446635 DOI: 10.4103/ijo.ijo_1480_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Purpose: Enhanced S-cone syndrome (ESCS), a rare disorder, is often misdiagnosed as other forms of retinal degenerations, which have a poorer prognosis than ESCS. The aim of this study is to report the varied clinical features of ESCS and distinguish it from other similar disorders. Methods: We retrospectively scrutinized the records of patients with confirmed diagnosis of ESCS and analyzed the findings. Results: We included 14 patients (age range 4–39 years) who were confirmed to have ESCS according to pathognomonic electroretinography (ERG) showing reduced photopic, combined responses, and 30 Hz flicker with reduced L, M cone responses and supernormal S cone responses. The disease presented in the 1st decade with night blindness and was almost stationary or minimally progressive. Mid-peripheral fundus changes in form of nummular pigmentary alterations, yellow punctate lesions, and macular schisis were noted. The vision ranged from 6/6 to 6/36 with follow-up ranging from 1month to 22 years. Conclusion: ESCS shows varied clinical features ranging from unremarkable fundus to pigment clumping and atrophic lesions. It has good prognosis with patients mostly maintaining their vision. ERG is diagnostic. More awareness and knowledge about this entity can help to differentiate it from other forms of night blindness.
Collapse
Affiliation(s)
- Anmol Naik
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Dhanashree Ratra
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Aniruddha Banerjee
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Daleena Dalan
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Sourabh Jandyal
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Girish Rao
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Parveen Sen
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Muna Bhende
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - V Jayaprakash
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Pradeep Susvar
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Jaydeep Walinjkar
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| | - Chetan Rao
- Department of Vitreoretinal Diseases, Medical Research Foundation, Sankara Nethralaya, College Road, Chennai, Tamil Nadu, India
| |
Collapse
|