Stargardt disease 1 (STGD1) is the most prevalent retinal dystrophy caused by pathogenic biallelic ABCA4 variants. Forty‐two unrelated patients mostly originating from Western China were recruited. ...Comprehensive ophthalmological examinations, including visual acuity measurements (subjective function), fundus autofluorescence (retinal imaging), and full‐field electroretinography (objective function), were performed. Next‐generation sequencing (target/whole exome) and direct sequencing were conducted. Genotype grouping was performed based on the presence of deleterious variants. The median age of onset/age was 10.0 (5–52)/29.5 (12–72) years, and the median visual acuity in the right/left eye was 1.30 (0.15–2.28)/1.30 (0.15–2.28) in the logarithm of the minimum angle of resolution unit. Ten patients (10/38, 27.0%) showed confined macular dysfunction, and 27 (27/37, 73.7%) had generalized retinal dysfunction. Fifty‐eight pathogenic/likely pathogenic ABCA4 variants, including 14 novel variants, were identified. Eight patients (8/35, 22.8%) harbored multiple deleterious variants, and 17 (17/35, 48.6%) had a single deleterious variant. Significant associations were revealed between subjective functional, retinal imaging, and objective functional groups, identifying a significant genotype–phenotype association. This study illustrates a large phenotypic/genotypic spectrum in a large well‐characterized STGD1 cohort. A distinct genetic background of the Chinese population from the Caucasian population was identified; meanwhile, a genotype–phenotype association was similarly represented.
We analyzed the effects of enzyme replacement therapy (ERT) on the visual acuity and visual fields of a patient with mucopolysaccharidosis type II, Hunter syndrome, with degeneration of the retina ...and abnormalities of the optic nerve. After the ERT, there was an improvement of the visual acuity and visual fields and an improvement of the activities of daily living. Despite the late onset of Hunter syndrome in this patient, ERT was still able to improve the visual function. We conclude that ERT should be considered regardless of the age of the manifestations of the signs and symptoms of Hunter syndrome.
Purpose
To report the 30-months’ course of macular dystrophy in a patient with genetically confirmed spinocerebellar ataxia type1 (SCA1).
Methods
Detailed ophthalmological examinations including ...best-corrected visual acuity (BCVA), perimetry, multimodal fundus imaging, and electrophysiological recordings were performed on a 52-year-old woman with SCA1. The number of CAG sequence repeats of the candidate gene was verified.
Results
The baseline decimal BCVA was 0.2 OD and 0.3 OS. Goldman perimetry showed relative central scotomas and slight enlargements of Mariotte blind spot bilaterally. Ophthalmoscopy revealed no abnormalities in the macula and optic disk. Fundus autofluorescence (FAF) showed a circular hyperautofluorescence and round-shaped hypoautofluorescence in the macula. Optical coherence tomography (OCT) showed a loss of the interdigitation zone and ellipsoid zone (EZ) in the macula. Full-field scotopic and photopic Full-field electroretinograms (ERGs) were normal, and multifocal ERGs were decreased in the central area. After 30 months, the BCVA had not changed, but the FAF showed a spark-like hypoautofluorescence in the macula. The abnormal area of the EZ had expanded toward the periphery, and the rate of EZ loss was 199.7%/year OD and 206.8%/year OS. Genetic examinations revealed an increase in the number of heterozygous CAG repeats in the
ATXN1
gene, and the CAG repeat number of the mutant allele ranged from 43 to 48.
Conclusions
The full-field scotopic and photopic ERGs were normal. The mfERGs were significantly smaller in the central region. OCT demonstrated bilateral photoreceptor atrophy in the macula, and the rate of EZ loss was more rapid than in other macular dystrophies. Spark-like hypoautofluorescence appeared during the course of the disease process which might be a specific feature of SCA1-related retinopathy.
Occult macular dystrophy (OMD) is the most prevalent form of macular dystrophy in East Asia. Beyond RP1L1, causative genes and mechanisms remain largely uncharacterised. This study aimed to delineate ...the clinical and genetic characteristics of OMD syndrome (OMDS). Patients clinically diagnosed with OMDS in Japan, South Korea, and China were enrolled. The inclusion criteria were as follows: (1) macular dysfunction and (2) normal fundus appearance. Comprehensive clinical evaluation and genetic assessment were performed to identify the disease-causing variants. Clinical parameters were compared among the genotype groups. Seventy-two patients with OMDS from fifty families were included. The causative genes were RP1L1 in forty-seven patients from thirty families (30/50, 60.0%), CRX in two patients from one family (1/50, 2.0%), GUCY2D in two patients from two families (2/50, 4.0%), and no genes were identified in twenty-one patients from seventeen families (17/50, 34.0%). Different severities were observed in terms of disease onset and the prognosis of visual acuity reduction. This multicentre large cohort study furthers our understanding of the phenotypic and genotypic spectra of patients with macular dystrophy and normal fundus. Evidently, OMDS encompasses multiple Mendelian retinal disorders, each representing unique pathologies that dictate their respective severity and prognostic patterns.
The aim of this study was to evaluate the effects of transcorneal electrical stimulation in subjects with primary open-angle glaucoma. Five eyes of four male subjects with primary open-angle glaucoma ...(average age: 52.25 ± 14.68 years) were enrolled. The subjects underwent transcorneal electrical stimulation every 3 months according to the following procedure. A Dawson-Trick-Litzkow electrode was placed on the cornea, and biphasic electric current pulses (10 ms, 20 Hz) were delivered using a stimulator (BPG-1,BAK Electronics) and a stimulus isolation unit (BSI-2). A current that evoked a phosphene that the subject perceived in the whole visual area was delivered continuously for 30 min. Humphrey visual field testing was performed after every third transcorneal electrical stimulation treatment. Changes in mean deviation (MD) values were evaluated with a linear regression model. Transcorneal electrical stimulation was performed 18.2 ± 9.4 times over a period of 49.8 ± 23.0 months. The average pretranscorneal electrical stimulation intraocular pressure, best corrected visual acuity, and MD values were 11.8 ± 1.79 mmHg, 0.14 ± 0.19 (logMAR) and −17.28 ± 6.24 dB, respectively. No significant differences were observed in intraocular pressure before and after transcorneal electrical stimulation. However, there was a significant positive linear relationship between changes in MD values and the number of transcorneal electrical stimulation treatments (R2 = 0.176, P = 0.005, Spearman correlation R =0.294, P = 0.008). Transcorneal electrical stimulation treatment may improve glaucomatous visual field defects in subjects with primary open-angle glaucoma. Large-scale studies are necessary to confirm these preliminary findings.
-associated retinopathy is a rare inherited retinal dystrophy, and its outcome has not been determined. A single retinal involvement by a mutation of the
gene is unexplained. We found three unrelated ...patients with a disease-causing
variant in a biallelic state from 1555 Japanese individuals of 1314 families with inherited retinal dystrophy. We reviewed their medical records and examined their peripheral lymphocytes by transmission electron microscopy (TEM).
was a 38-year-old woman who complained of night blindness and reduced vision. She developed macular degeneration at age 43 years.
and
were a man and a woman both of whom noticed night blindness in their 30s. Both had a degeneration in the macula and midperiphery in their 40s, which progressed to a diffuse retinal degeneration in their 60s when their vision was reduced to hand motions. Three novel
variants were identified. TEM of the lymphocytes of
and
showed abnormal structures in 40.6% and 0.3% of the peripheral lymphocytes, respectively. We concluded that the
-associated retinopathy of our patients was a progressive rod-cone dystrophy, and the visual outcome was poor. The systemic effect of
mutations may be compensable and have variations.
(
) is one of the causative genes of inherited retinal dystrophy. While the gene is relatively common in Caucasians, reports from Asian ethnicities are limited. In the present study, we report 40 ...Japanese patients from 30 families with
-associated retinal dystrophy. We identified 17 distinct pathogenic or likely pathogenic variants using next-generation sequencing. Variants p.R142W and p.V200E were relatively common in the cohort. The age of onset was generally in the 40's; however, some patients had earlier onset (age: 5 years). Visual acuity of the patients ranged from hand motion to 1.5 (Snellen equivalent 20/13). The patients showed variable phenotypes such as retinitis pigmentosa, cone-rod dystrophy, and macular dystrophy. Additionally, intrafamilial phenotypic variability was observed. Choroidal neovascularization was observed in three eyes of two patients with retinitis pigmentosa. The results demonstrate the genotypic and phenotypic variations of the disease in the Asian cohort.
The retinitis pigmentosa 2 (RP2) gene is one of the causative genes for X‐linked inherited retinal disorder. We characterized the clinical/genetic features of four patients with RP2‐associated ...retinal disorder (RP2‐RD) from four Japanese families in a nationwide cohort. A systematic review of RP2‐RD in the Japanese population was also performed. All four patients were clinically diagnosed with retinitis pigmentosa (RP). The mean age at examination was 36.5 (10–47) years, and the mean visual acuity in the right/left eye was 1.40 (0.52–2.0)/1.10 (0.52–1.7) in the logarithm of the minimum angle of resolution unit, respectively. Three patients showed extensive retinal atrophy with macular involvement, and one had central retinal atrophy. Four RP2 variants were identified, including two novel missense (p.Ser6Phe, p.Leu189Pro) and two previously reported truncating variants (p.Arg120Ter, p.Glu269CysfsTer3). The phenotypes of two patients with truncating variants were more severe than the phenotypes of two patients with missense variants. A systematic review revealed additional 11 variants, including three missense and eight deleterious (null) variants, and a statistically significant association between phenotype severity and genotype severity was revealed. The clinical and genetic spectrum of RP2‐RD was illustrated in the Japanese population, identifying the characteristic features of a severe form of RP with early macular involvement.
Purpose
The 2 most common causative genes for achromatopsia (ACHM) are
CNGA3
and
CNGB3
; other genes including
GNAT2
account for only a small portion of ACHM cases. The cone mosaics in eyes with
...CNGA3
and
CNGB3
variants are severely disrupted; the cone mosaics in patients with
GNAT2
-associated ACHM; however, have been reported to show a contiguous pattern in adaptive optics (AO) retinal images. The purpose of this study was to analyze the cone mosaic of another case of
GNAT2
-associated ACHM.
Patient and methods
The patient was a 17-year-old Japanese boy. Comprehensive ocular examinations including fundus photography, electroretinography (ERGs), optical coherence tomography (OCT), and whole-exome analysis were performed. The cone mosaic was recorded with a flood-illuminated AO fundus camera, and the cone density was compared with those of 10 normal control eyes.
Results
The patient had the typical phenotype of ACHM, and a novel homozygous variant, c.730_743del, in
GNAT2
was identified. The fundus did not show any specific abnormalities, and the OCT images showed the presence of the ellipsoid zone. The AO fundus image showed a clearly defined cone mosaic around the fovea. The cone density at 500 μm from the fovea was reduced by 15–30 % as compared with those of the normal eyes.
Conclusions
This is the first description of a Japanese patient with ACHM with a novel
GNAT2
variant. The eyes of this patient had a preserved cone structure with loss of function.
Background
Biallelic CLN3 gene variants have been found in either juvenile‐onset neuronal ceroid lipofuscinosis (JNCL) or isolated retinal dystrophy. It has been reported that most JNCL patients ...carry a common 1.02‐kb deletion variant homozygously. Clinical characteristics of patients with biallelic CLN3 missense variants are not well elucidated.
Methods
We described a 26‐year‐old Japanese male patient with isolated retinal dystrophy. Whole‐exome sequencing (WES) and transmission electron microscopy (TEM) were performed.
Results
Whole‐exome sequencing identified a novel homozygous CLN3 missense variant c.482C>T; p.(Ser161Leu). Ophthalmoscopy revealed retinal degeneration and macular atrophy, and later attenuated retinal vessels. Severely reduced responses were observed in both rod and cone electroretinograms. In TEM of the patient's lymphocytes, fingerprint profiles, which are specific findings in CLN3‐associated JNCL, were observed in 16/624 (2.56%) lymphocytes of the patient, who has never exhibited neurological signs during the 13‐year follow‐up period.
Conclusion
Our results indicated that this novel CLN3 missense variant is associated with teenage‐onset isolated retinal dystrophy. This is the first report of any patient with CLN3‐associated disorder in the Japanese population. Although fingerprint profiles have never been reported in CLN3‐associated isolated retinal dystrophy, these profiles were observed, albeit infrequently, suggesting that frequency of the fingerprint profiles might depend on variant types.
Biallelic CLN3 gene variants have been found in either juvenile‐onset neuronal ceroid lipofuscinosis or isolated retinal dystrophy. We described clinical and genetic characteristics of a Japanese patient with teenage‐onset isolated retinal dystrophy in whom a novel homozygous CLN3 missense variant was identified. This is the first report of a CLN3‐associated genetic disorder in the Japanese population.