Genetic characterization of 1210 Japanese pedigrees with inherited retinal diseases by whole-exome sequencing.

Inherited retinal diseases (IRDs) comprise a phenotypically and genetically heterogeneous group of ocular disorders that cause visual loss via progressive retinal degeneration. Here, we report the genetic characterization of 1210 IRD pedigrees enrolled through the Japan Eye Genetic Consortium and analyzed by whole exome sequencing. The most common phenotype was retinitis pigmentosa (RP, 43%), followed by macular dystrophy/cone- or cone-rod dystrophy (MD/CORD, 13%). In total, 67 causal genes were identified in 37% (448/1210) of the pedigrees. The first and second most frequently mutated genes were EYS and RP1, associated primarily with autosomal recessive (ar) RP, and RP and arMD/CORD, respectively. Examinations of variant frequency in total and by phenotype showed high accountability of a frequent EYS missense variant (c.2528G>A). In addition to the two known EYS founder mutations (c.4957dupA and c.8805C>G) of arRP, we observed a frequent RP1 variant (c.5797C>T) in patients with arMD/CORD.

CLEC3B is a novel causative gene for macular-retinal dystrophy.

PURPOSE: Macular degeneration is the leading cause of blindness worldwide. In this study, we aimed to define a new subtype of macular-retinal dystrophy and its genetic predisposition in 5 families. METHODS: Exome sequencing was performed to determine the putative disease-causing genes in patients with inherited macular disorders confirmed through comprehensive ophthalmic examinations. To validate its functional consequence, adeno-associated virus-mediated mutant gene was delivered into the murine retina, and both structural and functional tests were performed to investigate its pathological effects in vivo. RESULTS: In total, 5 multigenerational families diagnosed with autosomal dominant maculoretinopathy were found to carry a pathogenic variant in a new gene, CLEC3B, which encodes tetranectin, a plasminogen kringle-4 binding protein. Consistent with the disease phenotypes of patients, mice that received subretinal injections with the CLEC3B variant displayed multiple subretinal hyperreflective deposits, reduced retinal thickness, and decreased electroretinographic responses. Moreover, the optokinetic tracking response indicated that spatial frequency was significantly lower (P < .05), implying impaired visual function in these mice. CONCLUSION: We have presented a new subtype of macular-retinal dystrophy in 5 families as well as a new pathogenic gene, CLEC3B, providing new insights into maculoretinopathy etiology.

Vasodilatory effect of L-arginine on isolated rabbit and human posterior ciliary arteries in vitro and increased optic disc blood flow in vivo.

PURPOSE: This study aimed to clarify the vasodilatory effect of L-arginine on isolated rabbit and human posterior ciliary arteries (PCAs) and to investigate changes in optic disc blood flow after an infusion of L-arginine in vivo. METHODS: Vascular ring segments were mounted on a double myograph system. After obtaining maximal contraction following administration of high-K solution, L-arginine was administrated. Six volunteers received an intravenous drip infusion of 100 ml of L-arginine or saline. Changes in optic disc blood flow were measured by laser speckle flowgraphy. RESULTS: L-arginine relaxed high-K solution-induced contracted rabbit PCAs. Carboxy-PTIO (nitric oxide scavenger) and L-NAME (nitric oxide synthase inhibitor) inhibited L-arginine-induced relaxation in rabbit PCAs. After removal of the endothelium of the rabbit PCAs, L-arginine still relaxed rabbit PCAs. L-arginine relaxed human PCAs, despite the lack of nitric oxide production. In the L-arginine infusion group, the mean blur rate was significantly greater than that of the control group in vivo. CONCLUSION: L-arginine has both nitric oxide-dependent and independent vasodilatory effect on high K- induced contractions in isolated rabbit and human PCAs. L-arginine increased optic disc blood flow in vivo.

Cytomegalovirus retinitis as an adverse immunological effect of pulses of vincristine and dexamethasone in maintenance therapy for childhood acute lymphoblastic leukemia.

We describe a 5-year-old female with acute lymphoblastic leukemia (ALL) who suffered from cytomegalovirus (CMV) retinitis during maintenance therapy consisting of 6-mercaptopurine (6-MP) and methotrexate (MTX) with pulses of vincristine (VCR) and dexamethasone (DEX). Administration of anticytomegaloviral drugs led to a complete regression of active retinitis. Her low CD4 positive T cells and serum immunoglobulin G (IgG) recovered when maintenance therapy was resumed without VCR and DEX. The patient has been in complete remission (CR) for more than 5 months after completion of maintenance therapy without recurrence of CMV retinitis.

Comparison of combination therapy of prednisolone and cyclosporine with corticosteroid pulse therapy in Vogt-Koyanagi-Harada disease.

PURPOSE: To compare the efficacy and safety of a combination therapy of prednisolone and cyclosporine and corticosteroid pulse therapy in Vogt-Koyanagi-Harada (VKH) disease. STUDY DESIGN: A prospective, multicenter, randomized, non-inferiority trial. METHODS: Patients of new-onset acute VKH disease at 11 centers in Japan between 2014 and 2018 were randomized to a combination (oral prednisolone 60 mg daily with gradual taper-off to 35 mg/day and cyclosporine 3 mg/kg/day) and corticosteroid (methylprednisolone 1000 mg for 3 days followed by oral prednisolone) groups, and were followed for 1 year. RESULTS: Thirty-four were assigned to the combination and thirty-six patients to the corticosteroid group. Recurrence/worsening risk was 0.15 (95% confidence-interval [CI] 0.03-0.27) in the combination group and 0.25 (95% CI 0.11-0.39) in the corticosteroid group, with a risk difference of - 0.10 (90% CI - 0.27 to 0.06), demonstrating non-inferiority of the combination group with a non-inferiority margin of 0.20 (P = 0.0013). Serious adverse events occurred in three patients (two with hyponatremia and one with severe headaches) in the combination group and none in the corticosteroid group. Sunset glow fundus grades and cataract rates at 1 year were 0.57 (95% CI 0.42-71) and 4.3% in the combination group and 0.91 (95% CI 0.78-1.04) and 34.0% in the corticosteroid group, respectively. CONCLUSIONS: Combination therapy was noninferior to corticosteroid therapy with respect to recurrence/worsening risk. Notably, the recurrence/worsening risk, sunset glow fundus grade, and cataract rate were lower in the combination group than in the corticosteroid group.

Base Curve of Progressive Addition Lenses Influences Clear Vision and Stereopsis Area.

PURPOSE: Progressive addition lenses (PAL) are effective, particularly for middle-aged and elderly people who require reading spectacles. However, with PALs, peripheral vision may be distorted and blurred because of both the lateral bending of the surface and the effect of unequal bending of the light coming from an off-axis location in the tangential and sagittal directions, which may lead to a decrease in the quality of vision. Till date, no evaluation of PALs has been reported with regard to peripheral and binocular vision. We investigated the influence of high-base-curve PAL on the visual function of binocular vision using a synoptophore. METHODS: The subjects were seven males and 13 females aged 50-79 years with a best-corrected visual acuity of decimal visual acuity (1.0) or higher in both eyes and addition power of 1.50-2.50 diopters as the inclusion criteria. The study design was a two-group, two-period crossover trial. Using a synoptophore, the subjective clear vision area of monocular vision and stereopsis area of binocular vision were measured while wearing conventional-base curve PAL (4-curve) and high-base-curve PAL (8-curve). HOYALUX RF SPORT 1.6 lenses (HOYA Corporation, Tokyo, Japan) were used for the test PALs. RESULTS: The clear vision area of monocular vision was significantly wider when wearing the 8-curve PAL on the temporal side of the right eye (P = 0.02), and on the temporal side of the left eye (P = 0.01). The stereopsis area of binocular vision was significantly wider in all directions when wearing the 8-curve PAL: right (P = 0.02); left (P = 0.03); right 15° upward (P = 0.02); and left 15° upward (P = 0.02). CONCLUSION: It was clarified that, compared to 4-curve PAL, clear vision and stereopsis areas are wider when wearing 8-curve PAL.

Correction to: Clinical and genetic characteristics of 14 patients from 13 Japanese families with RPGR-associated retinal disorder: report of eight novel variants.

[This corrects the article DOI: 10.1038/s41439-019-0065-7.].

Clinical and genetic characteristics of 14 patients from 13 Japanese families with RPGR-associated retinal disorder: report of eight novel variants.

Variants in the retinitis pigmentosa GTPase regulator (RPGR) gene are a major cause of X-linked inherited retinal disorder (IRD). We herein describe the clinical and genetic features of 14 patients from 13 Japanese families harboring RPGR variants in a nationwide cohort. Comprehensive ophthalmological examinations were performed to classify the patients into one of the phenotype subgroups: retinitis pigmentosa (RP) and cone rod dystrophy (CORD). The mean age of onset/at examination was 13.8/38.1 years (range, 0-50/11-72), respectively. The mean visual acuity in the right/left eye was 0.43/0.43 (range, 0.1-1.7/-0.08-1.52) LogMAR unit. Eight patients had RP, and six had CORD. Whole-exome sequencing with target analyses identified 13 RPGR variants in 730 families with IRD, including 8 novel variants. An association between the phenotype subgroup and the position of variants (cutoff of amino acid 950) was revealed. To conclude, the clinical and genetic spectrum of RPGR-associated retinal disorder was first illustrated in a Japanese population, with a high proportion of novel variants. These results suggest the distinct genetic background of RPGR in the Japanese population, in which the genotype-phenotype association was affirmed. This evidence should be helpful monitoring and counseling patients and in selecting patients for future therapeutic trials.

A Case Report of Intravitreal Bevacizumab for Iris Metastasis of Small Cell Lung Carcinoma with Neovascular Glaucoma.

A 79-year-old man who had been diagnosed with small cell lung carcinoma (SCLC) complained of right ocular pain and blurred vision. His right intraocular pressure (IOP) was 30 mm Hg, and anterior chamber cells and multiple grayish white iris masses associated with peripheral anterior synechia (PAS) and neovascularization of the right iris were observed. We presumed that the iris masses were iris metastasis of SCLC. Despite therapy with topical eye drops and oral acetazolamide, the IOP was poorly controlled, so we injected intravitreal bevacizumab into his right eye for neovascular glaucoma. Neovascular glaucoma disappeared rapidly, but the IOP did not improve because of total PAS. To our knowledge, there is only one report of the use of intravitreal bevacizumab for SCLC metastasis in that eye and they reported that intravitreal injection resulted in successful short-term regression of presumed iris metastasis and improved control of secondary neovascular glaucoma, and the case had over one-half PAS. The previous report and our results suggest that secondary neovascular glaucoma with iris metastasis may be controlled by early intravitreal bevacizumab injection.

Identification of a novel RPGR exon ORF15 mutation in a family with X-linked retinitis pigmentosa.

OBJECTIVE: To investigate the phenotypic and genotypic characteristics of a novel mutation associated with X-linked retinitis pigmentosa (XLRP). METHODS: Six individuals in a family with XLRP were recruited, and clinical examinations were performed. All of the members were genotyped with microsatellite markers at loci that were considered to be associated with XLRP. The retinitis pigmentosa GTPase regulator gene (RPGR) was comprehensively screened using direct polymerase chain reaction sequencing. RESULTS: Genotyping analysis showed that the affected individuals in the family shared a common haplotype with selected markers. The patients demonstrated severe retinal degenerative phenotypes consistent with XLRP. Mutational screening of RPGR demonstrated a novel mutation, g.ORF15 + 1232_1233delGG. CONCLUSIONS: We identified a novel mutation in the 3' end of a highly repetitive region of exon open reading frame 15 (ORF15) and documented the detailed phenotypes of the patients with XLRP with the mutation. The clinical phenotype was consistent with XLRP, supporting the observation that the mutations in the 3' end of the ORF15 coding sequence give rise to XLRP. Clinical Relevance The mutation in the 3' end of the ORF15 coding sequence can lead to a spectrum of phenotypes, and the cone-predominant phenotype-related mutations can be located irregularly in exon ORF15.

Mutational analysis of RPGR and RP2 genes in Japanese patients with retinitis pigmentosa: identification of four mutations.

PURPOSE: To identify mutations in RPGR and RP2 genes in a series of Japanese retinitis pigmentosa (RP) families and to determine the association between the phenotypic changes in patients/carriers and the mutations. METHODS: A total of 37 unrelated RP families were recruited, three of which were with typical X-linked RP (XLRP), and other 34 families included 29 multiplex families and 5 simplex RP cases with no family history of RP. In addition, At least one RP patient had myopia >-3.0D in these families. RPGR and RP2 genes were comprehensively screened by using the direct polymerase chain reaction-sequencing method. Detailed phenotypes of the families with confirmed mutations were assessed by routine ophthalmic examinations, Goldmann perimetry, electroretinography and color fundus photography. RESULTS: Four mutations in RPGR and RP2 genes were identified. Of the three XLRP families, one had an ORF15 mutation and another had an RP2 mutation. Two ORF15 mutations were found in three of the other 34 RP families, with two families sharing a same mutation, g.ORF15+652-653delAG. All the three ORF15 mutations were first reported in the Japanese population. Affected males showed relatively severe symptoms while female carriers showed a wide spectrum of severity. A tapetal-like reflex was observed in two young females, indicating clinically the carrier status. CONCLUSIONS: We identified three ORF15 mutations and one RP2 mutation in five Japanese RP families. Moderate or severe myopia might be an indicator for the XLRP status in multiplex RP families which pedigree data are insufficient to allow accurate subtyping. It is suggested that mutational analysis of RPGR and RP2 may help to identify the causative mutation in a proportion of multiplex RP patients with myopia.

RCC1-like domain and ORF15: essentials in RPGR gene.

Clinical research into mutations of the RPGR gene showed that lack of either the RCC1-like domain of the ORF15 causes X-linked retinitis pigmentosa. Thus, the ORF15 and RCC1-like domain play a crucial role in the human retina. Further sudies on the role of the RCC1-like domain in the visual Cascade and additional findings of related proteins in the retina or even other organs, will give us a more precise understanding of this protein.

Clinical and molecular findings in three Japanese patients with crystalline retinopathy.

PURPOSE: To identify CYP4V2 mutations in three unrelated Japanese patients with Bietti crystalline corneoretinal dystrophy (BCD). METHODS: The three cases were diagnosed by ophthalmological examinations. All exons and flanking introns were amplified by polymerase chain reaction (PCR). PCR products were analyzed by direct sequencing. RNA was extracted from blood samples and analyzed by reverse transcriptase (RT)-PCR sequencing. RESULTS: Direct PCR sequencing demonstrated a homozygous mutation involving a 17-bp deletion together with a 2-bp insertion (c.802-8del17bp/insGC) in case 1 and case 3, and RT-PCR demonstrated that the complete length of exon 7 was missing; case 2 showed only a heterozygous change in exon 11 with no second mutation. CONCLUSION: A homozygous mutation was identified in two of the unrelated patients, and only a heterozygous change was detected in the third. These data indicate that c.802-8del17bp/insGC may be a frequent mutation in this gene.

Bilateral Rhegmatogenous Retinal Detachment during External Beam Radiotherapy.

Herein, we report a case of nontraumatic bilateral rhegmatogenous retinal detachment (RRD) during external beam radiotherapy for nonocular tumor, presented as an observational case study in conjunction with a review of the relevant literature. A 65-year-old male was referred to our hospital due to bilateral RRD. He underwent a biopsy for a tumor of the left frontal lobe 4 months prior to presentation, and the tumor had been diagnosed as primary central nerve system B-cell type lymphoma. He received chemotherapy and external beam radiotherapy for 1 month. There were no traumatic episodes. Bilateral retinal detachment occurred during a series of radiotherapies. Simultaneous nontraumatic bilateral retinal detachment is rare. The effects of radiotherapy on ocular functionality, particularly in cases involving retinal adhesion and vitreous contraction, may include RRD. Thus, it is necessary to closely monitor the eyes of patients undergoing radiotherapy, particularly those undergoing surgery for retinal detachment and those with a history of photocoagulation for retinal tears, a relevant family history, or risk factors known to be associated with RRD.

Novel deletion spanning RCC1-like domain of RPGR in Japanese X-linked retinitis pigmentosa family.

PURPOSE: To describe a macrodeletion spanning entire RCC1-like doman in the RPGR gene in one Japanese family with X-linked retinitis pigmentosa (XLRP). METHODS: Clinical ophthalmologic examinations were performed and genomic DNA was extracted from blood samples. Genomic DNA was analyzed by Southern blot and PCR amplification with specific primers. RESULTS: Patients had severe symptoms with early onset and rapid deterioration. PCR amplification and Southern blot analysis revealed the absence of the 5' half of the RPGR gene. The deletion was confirmed and characterized by designing flanking PCR primers: the deletion start point was located 80 bp upstream of the translation start site in exon 1, the end point was 42 bp downstream of exon 11. CONCLUSIONS: This 30 kb deletion contains the exons coding for the RCC1-like domain of RPGR. It is the first report of a macrodeletion that spans the entire RCC1-like domain of RPGR in X-linked retinitis pigmentosa patients, and suggests that loss of function of this domain disrupts the function of RPGR in human retina.

Laser speckle flowgraphy for differentiating between nonarteritic ischemic optic neuropathy and anterior optic neuritis.

PURPOSE: The aim of this study was to investigate the usefulness of laser speckle flowgraphy (LSFG) for the differentiation of acute nonarteritic ischemic optic neuropathy (NAION) from anterior optic neuritis (ON). METHODS: To investigate blood flow in the optic disc under normal conditions, NAION, and anterior ON, we compared the tissue blood flow of the right eye with that of the left eye in the control group, and that of the affected eye with that of the unaffected eye in the NAION and anterior ON groups. RESULTS: In the normal control group, the tissue blood flow did not significantly differ between the right and left eyes. In the NAION group, all 6 patients had decreased optic disc blood flow in the NAION eye when compared with the unaffected eye. By contrast, in the anterior ON group, all 6 patients had increased optic disc blood flow in the anterior ON eye when compared with the unaffected eye. In the NAION group, the mean blur rate (MBR) of the affected eyes was 29.5 % lower than that of the unaffected eyes. In the anterior ON group, the MBR of the affected eyes was 15.9 % higher than that of the unaffected eyes. CONCLUSIONS: LSFG could be useful in differentiating between NAION and anterior ON. In addition, this imaging technique saves time and is noninvasive.

Evaluation of inner retinal thickness around the optic disc using optical coherence tomography of a rodent model of nonarteritic ischemic optic neuropathy.

PURPOSE: To clarify the usefulness of optical coherence tomography (OCT) for the objective and quantitative evaluation of retinal nerve fiber layer (RNFL) thickness around the optic disc in a rodent model of nonarteritic ischemic optic neuropathy (rNAION). METHODS: Inner retinal thickness was measured using OCT before and after rNAION induction. The thicknesses of the RNFL and the inner plexiform layer (IPL) were measured using a histologic preparation before and 56 days after induction. We compared the inner retinal thickness measured by OCT with that measured by the histologic preparation. RESULTS: The mean inner retinal thickness around the optic disc of normal rats measured using OCT was similar to that measured using a histologic preparation (73.50 ± 4.94 vs. 75.94 ± 5.90 µm). The mean inner retinal thickness of rNAION significantly increased until the 7th day, returned to baseline on the 14th day, and decreased until the 90th day after induction. On the 56th day after rNAION induction, histologic measurements indicated that the mean RNFL thickness had decreased but that the IPL thickness was similar to that at baseline. CONCLUSION: The mean inner retinal thickness measured by OCT correlated with the RNFL thickness of rNAION. OCT is useful for the objective and quantitative evaluation of RNFL thickness around the optic disc in a model of rNAION.

Vasodilatory effects of antivascular endothelium growth factor (VEGF) antibody, corticosteroid, and nitric oxide on the posterior ciliary arteries.

PURPOSE: The purpose of this study was to determine whether an antivascular endothelium growth factor (VEGF) antibody, a corticosteroid, and sodium nitroprusside (SNP) [a nitric oxide (NO) donor] are possible treatment agents for nonarteritic ischemic optic neuropathy (NAION) by clarifying their effects on high-K (potassium) solution-induced contraction in isolated rabbit and human posterior ciliary arteries (PCA). METHODS: Vascular ring segments were cut from the distal section of the PCA and mounted in a double-myograph system. After obtaining the maximal contraction following the administration of high-K solution, bevacizumab as an anti-VEGF antibody, methylprednisolone as a corticosteroid, and SNP were administered separately. When a vasodilatory effect was observed, carboxy-PTIO (a NO scavenger) or L-NAME (a NO synthase inhibitor) was administered. RESULTS: Bevacizumab did not relax either the rabbit or the human PCA, whereas methylprednisolone relaxed both. Neither carboxy-PTIO nor L-NAME inhibited methylprednisolone-induced relaxation. SNP relaxed the rabbit PCA. Carboxy-PTIO inhibited SNP-induced relaxation, but L-NAME did not. In the human PCA, the vasodilatory effect of SNP was present, but weaker than in the rabbit PCA. CONCLUSIONS: A corticosteroid has NO-independent vasodilatory effects. Exogenous NO has a weak dilating effect in the human PCA. Therefore, corticosteroid could be effective for the treatment of NAION.

Effects of steroid administration and transcorneal electrical stimulation on the anatomic and electrophysiologic deterioration of nonarteritic ischemic optic neuropathy in a rodent model.

PURPOSE: To elucidate the effectiveness of steroid administration and transcorneal electrical stimulation (TES) on anatomic changes and visual function in a rodent model of nonarteritic ischemic optic neuropathy (rNAION). METHODS: Methylprednisolone (20 mg/kg) was injected through a central venous catheter twice a day for 3 days. TES was delivered with biphasic square pulses of 1 ms/phase, 100 µA of current, and 20 Hz of frequency for 60 min 3 h after induction on the 1st, 4th, 7th, 14th, and 28th days. RESULTS: Intravenous infusion of methylprednisolone significantly decreased the degree of acute disc edema but did not preserve the inner retinal thinning, decreasing the amplitude of scotopic threshold responses (STR) and decreasing retinal ganglion cell (RGC) numbers in rNAION. TES preserved the decreasing STR amplitude and the decreasing RGC numbers in rNAION. CONCLUSION: Steroids are effective for reducing disc edema in the acute stage in rNAION. TES is effective for preserving decreasing RGC numbers and function in the chronic stage of rNAION.

Effects of L-arginine on anatomical and electrophysiological deterioration of the eye in a rodent model of nonarteritic ischemic optic neuropathy.

PURPOSE: The aims of this study were to clarify the effectiveness of L-arginine (1) for reducing the severity of anatomical changes in the eye and improving visual function in the acute stage of a rodent model of nonarteritic ischemic optic neuropathy (rNAION) and (2) in preventing those changes in anatomy and visual function. METHODS: For the first aim, L-arginine was intravenously injected into rats 3 h after rNAION induction; for the second aim, rNAION was induced after the oral administration of L-arginine for 7 days. The inner retinal thickness was determined over time by optical coherence tomography, and the amplitude of the scotopic threshold response (STR) and the number of surviving retinal ganglion cells (RGCs) were measured. These data were compared with the baseline data from the control group. RESULTS: Both intravenous infusion of L-arginine after rNAION induction and oral pretreatment with L-arginine significantly decreased optic disc edema in the acute stage and thinning of the inner retina, reduced the decrease in STR amplitude, and reduced the decrease in the number of RGCs during rNAION. CONCLUSION: Based on these results, we conclude that L-arginine treatment is effective for reducing anatomical changes in the eye and improving visual function in the acute stage of rNAION and that pretreatment with L-arginine is an effective therapy to reduce the severity of the condition during recurrence in the other eye.