Association of the CYP39A1 G204E Genetic Variant with Increased Risk of Glaucoma and Blindness in Patients with Exfoliation Syndrome.

PURPOSE: Carriers of functionally deficient mutations in the CYP39A1 gene have been recently reported to have a 2-fold increased risk of exfoliation syndrome (XFS). The aim of this study was to evaluate the risk of blindness and related clinical phenotypes of XFS patients carrying the loss-of-function CYP39A1 G204E mutation in comparison with XFS patients without any CYP39A1 mutation. DESIGN: Retrospective case study. PARTICIPANTS: A total of 35 patients diagnosed with XFS carrying the CYP39A1 G204E mutation and 150 XFS patients without any CYP39A1 mutation who were randomly selected from the Japanese XFS cohort. METHODS: Two-sided Fisher exact test with an alpha level < 0.05 was used to estimate the significance of the calculated odds ratio (OR) for all categorical measures. Comparisons between groups of subjects were performed using linear mixed effect models with group as random effect and taking possible dependence between eyes within a subject into account. MAIN OUTCOME MEASURES: Primary analysis compared the incidence of blindness (defined as visual acuity [VA] < 0.05 decimal), prevalence of exfoliation glaucoma (XFG), history of glaucoma surgery, and indices of glaucoma severity such as visual field (VF) mean deviation (MD), intraocular pressure (IOP), and vertical cup-disc ratio (CDR) between CYP39A1 G204E carriers and those without any CYP39A1 mutation. RESULTS: The overall risk for blindness was significantly higher in XFS patients carrying the CYP39A1 G204E variant (10/35 [28.6%]) compared with XFS patients without any CYP39A1 mutations (8/150 [5.4%]; odds ratio [OR], 7.1; 95% confidence interval [CI], 2.7-20.2]; P < 0.001). A higher proportion of XFS patients with the CYP39A1 G204E mutation (23/35 [65.7%]) had evidence of XFG in at least 1 eye compared with the comparison group (41/150 [27.3%]; OR, 5.1; 95% CI, 2.4-11.4]; P < 0.0001). Significantly higher peak IOP, larger vertical CDR, and worse VF MD were also found in CYP39A1 G204E variant carriers (P < 0.001). Additionally, patients with the CYP39A1 G204E mutation (18/35 [51.4%]) required more laser or glaucoma surgical interventions compared with those without any CYP39A1 mutation (32/150 [21.3%], P < 0.001). CONCLUSIONS: Patients with XFS carrying the CYP39A1 G204E mutation had significantly increased risk of blindness, higher occurrence of XFG, and more severe glaucoma compared with patients with XFS without any CYP39A1 mutation.

Association of Rare CYP39A1 Variants With Exfoliation Syndrome Involving the Anterior Chamber of the Eye.

Importance: Exfoliation syndrome is a systemic disorder characterized by progressive accumulation of abnormal fibrillar protein aggregates manifesting clinically in the anterior chamber of the eye. This disorder is the most commonly known cause of glaucoma and a major cause of irreversible blindness. Objective: To determine if exfoliation syndrome is associated with rare, protein-changing variants predicted to impair protein function. Design, Setting, and Participants: A 2-stage, case-control, whole-exome sequencing association study with a discovery cohort and 2 independently ascertained validation cohorts. Study participants from 14 countries were enrolled between February 1999 and December 2019. The date of last clinical follow-up was December 2019. Affected individuals had exfoliation material on anterior segment structures of at least 1 eye as visualized by slit lamp examination. Unaffected individuals had no signs of exfoliation syndrome. Exposures: Rare, coding-sequence genetic variants predicted to be damaging by bioinformatic algorithms trained to recognize alterations that impair protein function. Main Outcomes and Measures: The primary outcome was the presence of exfoliation syndrome. Exome-wide significance for detected variants was defined as P < 2.5 × 10-6. The secondary outcomes included biochemical enzymatic assays and gene expression analyses. Results: The discovery cohort included 4028 participants with exfoliation syndrome (median age, 78 years [interquartile range, 73-83 years]; 2377 [59.0%] women) and 5638 participants without exfoliation syndrome (median age, 72 years [interquartile range, 65-78 years]; 3159 [56.0%] women). In the discovery cohort, persons with exfoliation syndrome, compared with those without exfoliation syndrome, were significantly more likely to carry damaging CYP39A1 variants (1.3% vs 0.30%, respectively; odds ratio, 3.55 [95% CI, 2.07-6.10]; P = 6.1 × 10-7). This outcome was validated in 2 independent cohorts. The first validation cohort included 2337 individuals with exfoliation syndrome (median age, 74 years; 1132 women; n = 1934 with demographic data) and 2813 individuals without exfoliation syndrome (median age, 72 years; 1287 women; n = 2421 with demographic data). The second validation cohort included 1663 individuals with exfoliation syndrome (median age, 75 years; 587 women; n = 1064 with demographic data) and 3962 individuals without exfoliation syndrome (median age, 74 years; 951 women; n = 1555 with demographic data). Of the individuals from both validation cohorts, 5.2% with exfoliation syndrome carried CYP39A1 damaging alleles vs 3.1% without exfoliation syndrome (odds ratio, 1.82 [95% CI, 1.47-2.26]; P < .001). Biochemical assays classified 34 of 42 damaging CYP39A1 alleles as functionally deficient (median reduction in enzymatic activity compared with wild-type CYP39A1, 94.4% [interquartile range, 78.7%-98.2%] for the 34 deficient variants). CYP39A1 transcript expression was 47% lower (95% CI, 30%-64% lower; P < .001) in ciliary body tissues from individuals with exfoliation syndrome compared with individuals without exfoliation syndrome. Conclusions and Relevance: In this whole-exome sequencing case-control study, presence of exfoliation syndrome was significantly associated with carriage of functionally deficient CYP39A1 sequence variants. Further research is needed to understand the clinical implications of these findings.

Phenotypical Characteristics of POC1B-Associated Retinopathy in Japanese Cohort: Cone Dystrophy With Normal Funduscopic Appearance.

Purpose: Cone/cone-rod dystrophy is a large group of retinal disorders with both phonotypic and genetic heterogeneity. The purpose of this study was to characterize the phenotype of eight patients from seven families harboring POC1B mutations in a cohort of the Japan Eye Genetics Consortium (JEGC). Methods: Whole-exome sequencing with targeted analyses identified homozygous or compound heterozygous mutations of the POC1B gene in 7 of 548 families in the JEGC database. Ophthalmologic examinations including the best-corrected visual acuity, perimetry, fundus photography, fundus autofluorescence imaging, optical coherence tomography, and full-field and multifocal electroretinography (ERGs) were performed. Results: There were four men and four women whose median age at the onset of symptoms was 15.6 years (range, 6-23 years) and that at the time of examination was 40.3 years (range, 22-67 years). The best-corrected visual acuity ranged from -0.08 to 1.52 logMAR units. The funduscopic appearance was normal in all the cases except in one case with faint mottling in the fovea. Optical coherence tomography revealed an absence of the interdigitation zone and blurred ellipsoid zone in the posterior pole, but the foveal structures were preserved in three cases. The full-field photopic ERGs were reduced or extinguished with normal scotopic responses. The central responses of the multifocal ERGs were preserved in two cases. The diagnosis was either generalized cone dystrophy in five cases or cone dystrophy with foveal sparing in three cases. Conclusions: Generalized or peripheral cone dystrophy with normal funduscopic appearance is the representative phenotype of POC1B-associated retinopathy in our cohort.

Twelve-month efficacy and safety of glaucoma filtration device for surgery in patients with normal-tension glaucoma.

PURPOSE: To assess the efficacy and safety of filtration surgery using the EX-PRESS glaucoma filtration device in patients with normal-tension glaucoma (NTG). STUDY DESIGN: Prospective, single-arm, multicenter interventional case series. METHODS: Eyes with NTG underwent EX-PRESS implantation with or without cataract surgery. The efficacy and safety were assessed at 1 day; 1 and 2 weeks; and 1, 3, 6, and 12 months after surgery. The main outcome measure was reduction in intraocular pressure (IOP) from baseline at 3, 6, and 12 months after surgery. Safety assessments included adverse event incidence, postoperative inflammation, and corneal endothelial cell density. RESULTS: Thirty-two Japanese patients (37 eyes) with NTG were enrolled. The mean IOP decreased from 14.8 ± 2.3 mmHg at baseline to 10.0 ± 3.1 mmHg at 12 months after surgery (mean reduction 4.9 ± 4.2 mmHg [31.1%]; P < .0001). IOP-lowering medication use decreased from a mean of 3.3 medications per eye before surgery to 0.1 medications per eye at 12 months after surgery. IOP reductions > 20% were achieved by 61.5% of the eyes at 12 months. Adverse events were typical for filtration procedures, and none was deemed device-related. Postoperative inflammation was mild and self-limiting. The mean corneal endothelial cell density had decreased by 3.3% at 12 months after surgery. CONCLUSION: The EX-PRESS glaucoma filtration device is safe and effective for filtration surgery in patients with NTG, providing mean IOP reduction consistent with recommendations based on the Collaborative NTG Study.

Common variants in the COL2A1 gene are associated with lattice degeneration of the retina in a Japanese population.

Purpose: Lattice degeneration of the retina is a vitreoretinal disorder characterized by a visible fundus lesion that predisposes the patient to retinal detachment. It has been suggested that collagen type II alpha 1 (COL2A1) gene variants may contribute to the development of disorders associated with retinal detachment. Here we investigated whether COL2A1 gene variants were associated with the risk of lattice degeneration of the retina. Methods: We recruited 634 Japanese patients with lattice degeneration of the retina and 1694 Japanese healthy controls. We genotyped 13 tagging single-nucleotide polymorphisms (SNPs) in COL2A1. We also performed imputation analysis to evaluate the potential association of un-genotyped COL2A1 SNPs, involving the imputation of 65 SNPs. Results: Two intronic SNPs-rs1793954 and rs1635533-were significantly associated with lattice degeneration of the retina. The SNP rs1793954 showed the strongest association, with its C allele carrying an increased disease risk (p = 0.0016, corrected p = 0.021, OR = 1.25). The rs1793954 and rs1635533 SNPs were in strong linkage disequilibrium with each other (r 2 = 0.99), and conditional analysis revealed that rs1793954 could account for the association between rs1635533 and the disease. Conclusions: Our results suggested that COL2A1 gene variants may contribute to the development of lattice degeneration of the retina. Further genetic and functional analyses of COL2A1 variants are needed to clarify the present findings.

High interleukin-8 level in aqueous humor is associated with poor prognosis in eyes with open angle glaucoma and neovascular glaucoma.

Glaucoma is a leading cause of blindness worldwide. Purpose of this study was to identify molecular markers that were significantly correlated with presence of glaucoma and outcome of glaucoma surgery. To accomplish this, we determined the profiles of pro-inflammatory cytokines in the aqueous humor of 101 glaucoma patients; 31 primary open angle glaucoma (POAG), 38 pseudoexfoliation glaucoma (PEG), and 32 neovascular glaucoma (NVG). We also studied 100 normal subjects as controls. In eyes with POAG or PEG, the level of interleukin (IL)-1α, IL-2, IL-4, IL-8, IL-23, and CCL2 were significantly elevated. In the NVG eyes, many inflammatory cytokines were also highly elevated. IL-8 had the highest odds ratio, and levels of IL-8 and CCL2 were significantly correlated with preoperative IOP or visual field defects in PEG eyes. Principal component analysis showed that IL-8 had the highest association to the IOP-cytokine component, and Cox proportional hazard model indicated that an elevation of IL-8 was a significant risk of filtering surgery failure. Together with modeling of their interactions and prognosis, IL-8 elevation is a significant risk factor both for detecting and managing glaucoma and may serve as a therapeutic target candidate to improve the prognosis of glaucoma surgery.

Treat-and-extend versus every-other-month regimens with aflibercept in age-related macular degeneration.

PURPOSE: To compare the 1-year outcomes of treat-and-extend (TAE) and every-other-month (2M) regimens with intravitreal aflibercept in Japanese wet age-related macular degeneration (AMD) patients. METHODS: Prospective, multicenter, randomized clinical trial. The primary outcome measure was the proportion of eyes in which the best-corrected visual acuity (BCVA) was maintained at week 52 [with a loss of <0.3 logarithm of minimum angular of resolution (logMAR) units]. The secondary outcome measures were the mean change from baseline in the central retinal thickness (CRT) and the number of injections. RESULTS: Forty-one patients were enrolled. The mean changes in the BCVA from baseline in the TAE and 2M were -0.32 ± 0.27 and -0.26 ± 0.30 logMAR units (p = 0.46). The TAE group was noninferior to the 2M group in BCVA maintenance. The mean CRT changes from baseline in the TAE and 2M were -161 ± 133 and -157 ± 90 µm (p = 0.73). The mean number of injections in the TAE and 2M were 7.5 ± 1.2 (range, 7-12) and 8.0 ± 0.0 (p < 0.0001). CONCLUSION: Treat-and-extend (TAE) regimen with aflibercept improved the BCVA and CRT to the same extent as 2M regimen, with a reduced number of injections.

A common variant mapping to CACNA1A is associated with susceptibility to exfoliation syndrome.

Exfoliation syndrome (XFS) is the most common recognizable cause of open-angle glaucoma worldwide. To better understand the etiology of XFS, we conducted a genome-wide association study (GWAS) of 1,484 cases and 1,188 controls from Japan and followed up the most significant findings in a further 6,901 cases and 20,727 controls from 17 countries across 6 continents. We discovered a genome-wide significant association between a new locus (CACNA1A rs4926244) and increased susceptibility to XFS (odds ratio (OR) = 1.16, P = 3.36 × 10(-11)). Although we also confirmed overwhelming association at the LOXL1 locus, the key SNP marker (LOXL1 rs4886776) demonstrated allelic reversal depending on the ancestry group (Japanese: OR(A allele) = 9.87, P = 2.13 × 10(-217); non-Japanese: OR(A allele) = 0.49, P = 2.35 × 10(-31)). Our findings represent the first genetic locus outside of LOXL1 surpassing genome-wide significance for XFS and provide insight into the biology and pathogenesis of the disease.

Findings of secondary corneal amyloidosis with ultrahigh-resolution optical coherence tomography.

PURPOSE: To describe observations by ultrahigh-resolution optical coherence tomography (OCT) in a secondary corneal amyloidosis (SCA) patient with histological analysis of excised tissue. A unique finding under OCT of her fellow eye is also described. CASE: A 39-year-old female had suffered from trichiasis in both of her eyes for more than 30 years. Slit-lamp examination showed a milky-white soft mass on her left cornea and a linear opacity on the fellow cornea at the cilia-attached region. OCT demonstrated the presence of a mass region within a thin epithelial layer and no destruction of Bowman's layer in her left cornea. In the fellow cornea, which exhibited a linear opacity, a high-density spot in Bowman's layer was observed at the cilia-attached region covered by the epithelial layer, with normal thickness. Histological examination of the excised cornea showed that the mass was positive with both Congo red and antilactoferrin antibody. CONCLUSION: SCA, amyloid gradually accumulates above Bowman's layer, occupying the epithelial layer, with no destruction of Bowman's layer until the advanced stage. A high-density spot in Bowman's layer might be the first stage of SCA.

Common variants in the COL4A4 gene confer susceptibility to lattice degeneration of the retina.

Lattice degeneration of the retina is a vitreoretinal disorder characterized by a visible fundus lesion predisposing the patient to retinal tears and detachment. The etiology of this degeneration is still uncertain, but it is likely that both genetic and environmental factors play important roles in its development. To identify genetic susceptibility regions for lattice degeneration of the retina, we performed a genome-wide association study (GWAS) using a dense panel of 23,465 microsatellite markers covering the entire human genome. This GWAS in a Japanese cohort (294 patients with lattice degeneration and 294 controls) led to the identification of one microsatellite locus, D2S0276i, in the collagen type IV alpha 4 (COL4A4) gene on chromosome 2q36.3. To validate the significance of this observation, we evaluated the D2S0276i region in the GWAS cohort and in an independent Japanese cohort (280 patients and 314 controls) using D2S0276i and 47 single nucleotide polymorphisms covering the region. The strong associations were observed in D2S0276i and rs7558081 in the COL4A4 gene (Pc = 5.8 × 10(-6), OR = 0.63 and Pc = 1.0 × 10(-5), OR = 0.69 in a total of 574 patients and 608 controls, respectively). Our findings suggest that variants in the COL4A4 gene may contribute to the development of lattice degeneration of the retina.

Oguchi disease masked by retinitis pigmentosa.

The purpose of this study was to report a patient with Oguchi disease whose ophthalmological characteristics were masked by retinitis pigmentosa (RP). The method used in this study was case report. A 53-year-old man had a progressive decrease in his visual acuity and was diagnosed with RP because of night blindness, fundoscopic findings, ring scotoma, and extinguished single-flash electroretinograms (ERGs). However, a faint golden-yellowish reflex of the retina prompted us to make a more detailed examination of the fundus after a long period of dark adaptation, ERGs, and genetic analysis. Examinations showed the Mizuo-Nakamura phenomenon, relative intact photopic ERGs, and a SAG mutation, and the patient was diagnosed with RP associated with Oguchi disease. When RP accompanies Oguchi disease, the clinical characteristics of Oguchi disease might be masked. In such a situation, the correct diagnosis is difficult. However, careful analysis of clinical findings will suggest Oguchi disease, which can be confirmed by molecular genetics.

Morphological changes of corneal subepithelial nerve plexus in different types of herpetic keratitis.

PURPOSE: We investigated by in vivo confocal microscopy alterations in the subepithelial nerve plexus in different types of herpes simplex keratitis (HSK). METHODS: Seventeen patients (seven women and ten men, mean age 63.9 years) with a history of HSK were classified into three groups according to the classification of Herpetic Keratitis Infection Research Group. Slit-lamp examinations, corneal sensitivity measurements, and corneal in vivo confocal microscopy examinations [Rostock Corneal Module attached to the Heidelberg Retina Tomograph II (HRT II-RCM)] were performed. RESULTS: Among the 17 cases, three were classified as epithelial type, ten as stromal type, and four as endothelial type HSK. The average corneal sensitivities were 11.41 ± 9.46 mm in the affected eyes and 43.24 ± 12.2 mm in controls. Decreases in three parameters in the affected eyes (long nerve-fiber density, nerve-branch density, nerve thickness) were statistically significant compared with controls. Decreases in the three parameters were more remarkable in the epithelial and stromal types than in the endothelial type. CONCLUSION: The morphology of the corneal subepithelial nerve plexus may get gradually destroyed along with recurrent episodes of epithelial and stromal HSK. However, the destruction does not seem remarkable in the endothelial type of HSK, suggesting the possibility of a different route of virus recruitment in this type.

[Retinal vein occlusion followed by ischemic optic neuropathy with anticardiolipin IgG antibody: a case report].

BACKGROUND: Anticardiolipin antibodies in the autoimmune mechanism can cause vasculitis, leading to hypercoagulability-related thrombosis. We report a case of retinal vein occlusion followed by ischemic optic neuropathy in a young woman with anticardiolipin IgG antibody. CASE: A 17-year-old woman with dilatation and tortuosity of the retinal veins and retinal hemorrhage in the superior quadrant of the retina OS. Fluorescein retinal angiography showed a delay of filling time in the upper quadrant of the retina and a 3mm-continuous stain along the superior retinal vein. Laboratory tests were repeatedly positive for anticardiolipin IgG antibodies. Although the retinal hemorrhage disappeared 2 months after subtennon injection of 20 mg triamcinolone acetonide (TA), ischemic optic neuropathy occurred 9 months later. CONCLUSIONS: The staining of the vessel wall and the effectiveness of TA suggest that vasculitis may be associated with the pathology of this condition. The presence of anticardiolipin IgG antibodies suggests that autoimmune mechanism is involved in the vasculitis.

Robot-assisted vitreoretinal surgery: development of a prototype and feasibility studies in an animal model.

PURPOSE: To develop a prototype robotic system designed to assist vitreoretinal surgery and to evaluate its accuracy and maneuverability. DESIGN: Experimental study. PARTICIPANTS: This study used harvested porcine eyes. METHODS: After development of a prototype robotic system, pointing accuracy tests of the system were performed on graph paper and in harvested porcine eyes. The average maximal deviation from the aiming point to the actual position of the tip of the instrument was compared between manually conducted procedures and those conducted with robotic assistance. The feasibility of creating posterior vitreous detachment (PVD), retinal vessel sheathotomy (RVS), and retinal vessel microcannulation also were evaluated in porcine eye models, and the success rates of 4 consecutive attempts for each kind of procedure were evaluated. MAIN OUTCOME MEASURES: The average maximum deviation in pointing accuracy tests both on graph paper and in animal eye models was a main outcome measure. The success rate of making PVD, RVS, and retinal vessel microcannulation was the other primary outcome measure. RESULTS: The pointing accuracy was superior with robotic assistance both on graph paper (327.0 microm vs. 32.3 microm) and in animal eye models (140.8 microm vs. 33.5 microm). Creating PVD, RVS, and retinal vessel microcannulation was feasible in 4 of 4 attempts, 4 of 4 attempts, and 2 of 4 attempts, respectively. The 2 failures in microcannulation were considered to be the result of difficulty in visual differentiation between the retinal vessel and retina in harvested porcine eyes. CONCLUSIONS: Improved accuracy and desirable feasibility of a prototype robotic system to assist vitreoretinal surgery were shown in this study. Research for wider implementation of robot-assisted surgery should be continued; there are some hurdles to overcome.

Ocular manifestations of congenital insensitivity to pain with anhidrosis.

PURPOSE: To describe ocular manifestations in Japanese patients with congenital insensitivity to pain with anhidrosis (CIPA), focusing particularly on the status of the ocular surface. DESIGN: Observational case series. METHODS: Eighteen patients with CIPA underwent applicable ophthalmologic examinations, including visual acuity, refraction, slit-lamp examination, fundus examination, tear breakup time, Schirmer 1 test, corneal sensitivity, and corneal topography. RESULTS: Superficial punctate keratopathy (SPK) was observed at the interpalpebral area in 23 (64%) of 36 eyes. Corneal opacity was observed in three eyes (8.3%). Tear breakup time was below the lower limit of the normal range in all examined eyes, and the value of Schirmer 1 test was above the lower limit of the normal range in most of the examined eyes. CONCLUSIONS: Superficial punctate keratopathy is observed in most cases of CIPA, which might predispose patients to corneal infection. Investigation of dry eye in patients with CIPA will provide unique opportunities to explore the critical roles of the autonomic sympathetic nervous system as well as the sensory nervous system in the physiology of tear production.

Nanotechnology-based photodynamic therapy for neovascular disease using a supramolecular nanocarrier loaded with a dendritic photosensitizer.

Photodynamic therapy (PDT) for exudative age-related macular degeneration (AMD) was evaluated using a supramolecular nanomedical device, that is, a novel dendritic photosensitizer (DP) encapsulated by a polymeric micelle formulation. The characteristic dendritic structure of the DP prevents aggregation of its core sensitizer, thereby inducing a highly effective photochemical reaction. With its highly selective accumulation on choroidal neovascularization (CNV) lesions, this treatment resulted in a remarkably efficacious CNV occlusion with minimal unfavorable phototoxicity.

Effective accumulation of polyion complex micelle to experimental choroidal neovascularization in rats.

Exudative age-related macular degeneration, characterized by choroidal neovascularization (CNV), is a major cause of visual loss. In this study, we examined the distribution of the polyion complex (PIC) micelle encapsulating FITC-P(Lys) in blood and in experimental CNV in rats to investigate whether PIC micelle can be used for treatment of CNV. We demonstrate that PIC micelle has long-circulating characteristics, accumulating to the CNV lesions and is retained in the lesion for as long as 168 h after intravenous administration. These results raise the possibility that PIC micelles can be used for achieving effective drug targeting to CNV.

Suture fixation of an intraocular lens combined with pars plana vitrectomy and gas tamponade.

We describe suturing an intraocular lens (IOL) after pars plana lensectomy and vitrectomy combined with gas tamponade in 4 patients with vitreoretinal disease and subluxated lenses that could not be managed with capsular tension rings. The IOL haptics were sutured before the fluid-gas exchange in a horizontal (case 1), oblique (cases 2 and 4), and vertical (case 3) manner. In a case of unavoidable horizontal fixation due to limited scleral space, the upper part of the IOL tilted anteriorly postoperatively because of the enhanced effect of the gas bubble. A peripheral anterior iris synechia also occurred. The IOL remained well positioned in cases with oblique and vertical fixations, and no other complications occurred. Careful preoperative planning of the surgical design can help avoid unnecessary horizontal fixation.