Syndromic retinitis pigmentosa caused by biallelic SCAPER frameshift variant.

PURPOSE: Mutations in the SCAPER gene have previously been reported to be a rare cause of syndromic and non-syndromic autosomal recessive retinitis pigmentosa (RP). We report a case of syndromic RP caused by a frameshift heterozygous mutation in SCAPER. Our case has a relatively mild ocular phenotype with the presence of cone involvement noted on full field electroretinogram (ffERG) without impacting central or color vision. MATERIALS AND METHODS: A 17-year-old male presented with progressive nyctalopia in both eyes. He underwent ophthalmic examination and multimodal imaging. A complete retinal degeneration panel consisting of 322 genes was used to screen for molecular causes of retinal dystrophy in this patient along with family segregation analysis. RESULTS: Fundus examination of the proband revealed mild RP phenotype with waxy pallor of optic discs, attenuated retinal arterioles, and single bone spicule like pigmentary change in the mid-periphery bilaterally. Multimodal imaging and ffERG demonstrated a picture of RP with cone dysfunction without impacting central or color vision bilaterally. Examined family members were found to be normal. The proband was found to be heterozygous for two novel frameshift pathogenic variants in SCAPER c.3781del, p. (Val1261Serfs*26), c.868_869del, p. (Glu290Serfs*7) both leading to predicted premature termination. The family members tested were found to be heterozygous for SCAPER c.868_869del, p. (Glu290Serfs*7) pathogenic variant confirming their carrier status. CONCLUSION: We report a case of a syndromic RP of previously unreported ocular phenotype associated with SCAPER pathogenic variant, which will add to the phenotypic spectrum of retinopathy and systemic features associated with pathogenic variants in SCAPER.

Investigating the associations of macular edema in retinitis pigmentosa.

Macular edema (ME), the accumulation of intraretinal fluid in the macula, is a common sight affecting sequelae of retinitis pigmentosa (RP). However, it is unclear why some patients develop ME, and others do not. This study aims to identify associations between clinical-genetic factors in RP with ME. Patients with clinically confirmed RP cases were identified from the inherited retinal disease database at a large tertiary referral academic center. Demographic and genetic testing findings were noted. Additionally, optical coherence tomography volume scans were graded using a validated grading system. One hundred and six patients (73.1%) were found to have ME in at least one eye (OD = 88, mean = 37.9%, OS = 98, mean = 31.7%). Structurally, the presence of epiretinal membrane (ERM) (p < 0.007) and vitreo-macular traction (VMT) (p < 0.003) were significantly associated with ME. Additionally, X-linked (p < 0.032) and autosomal dominant inheritance (p < 0.039) demonstrated a significant association with ME, with RP1 (p < 0.045) and EYS (p < 0.017) pathogenic variants also significantly associated with ME. This study, in a large cohort of RP patients, confirms previous retinal structural associations for ME in RP and identifies potential new genetic associations.

Efficacy and accuracy of artificial intelligence to overlay multimodal images from different optical instruments in patients with retinitis pigmentosa.

BACKGROUND: Retinitis pigmentosa (RP) represents a group of progressive, genetically heterogenous blinding diseases. Recently, relationships between measures of retinal function and structure are needed to help identify outcome measures or biomarkers for clinical trials. The ability to align retinal multimodal images, taken on different platforms, will allow better understanding of this relationship. We investigate the efficacy of artificial intelligence (AI) in overlaying different multimodal retinal images in RP patients. METHODS: We overlayed infrared images from microperimetry on near-infra-red images from scanning laser ophthalmoscope and spectral domain optical coherence tomography in RP patients using manual alignment and AI. The AI adopted a two-step framework and was trained on a separate dataset. Manual alignment was performed using in-house software that allowed labelling of six key points located at vessel bifurcations. Manual overlay was considered successful if the distance between same key points on the overlayed images was ≤1/2°. RESULTS: Fifty-seven eyes of 32 patients were included in the analysis. AI was significantly more accurate and successful in aligning images compared to manual alignment as confirmed by linear mixed-effects modelling (p < 0.001). A receiver operating characteristic analysis, used to compute the area under the curve of the AI (0.991) and manual (0.835) Dice coefficients in relation to their respective 'truth' values, found AI significantly more accurate in the overlay (p < 0.001). CONCLUSION: AI was significantly more accurate than manual alignment in overlaying multimodal retinal imaging in RP patients and showed the potential to use AI algorithms for future multimodal clinical and research applications.

Further delineation of the CWC27-associated spliceosomeopathy: Case report and review of the literature.

Pre-mRNA splicing factors are crucial in regulating transcript diversity, by removing introns from eukaryotic transcripts, an essential step in gene expression. Splicing of pre-mRNA is catalyzed by spliceosomes. CWC27 is a cyclophilin associated with spliceosome, in which genetic defects of its components have been linked to spliceosomopathies with clinical phenotypes including skeletal developmental defects, retinitis pigmentosa (RP), short stature, skeletal anomalies, and neurological disorders. We report two siblings (male and female) of Mexican descent with a novel homozygous frameshift variant in CWC27 and aim to highlight the cardinal features among the previously described 12 cases as well as expand the currently recognized phenotypic spectrum. Both siblings presented with a range of ocular and extraocular manifestations including novel features such as solitary kidney and tarsal coalition in the male sibling, together with gait abnormalities, and Hashimoto's thyroiditis in the female sibling. Finally, we highlight ectodermal involvement including sparse scalp hair, eyebrows and lashes, pigmentary differences, nail dysplasia, and dental anomalies as a core phenotype associated with the CWC27 spliceosomopathy.

Dent disease presenting with nyctalopia and electroretinographic correlates of vitamin A deficiency.

Purpose: To report a unique case of Dent Disease presenting with nyctalopia associated with vitamin A deficiency and abnormal electroretinogram findings without prior systemic symptomatology. Observations: A 16-year-old male presented with a several month history of nyctalopia and peripheral vision deficits. Central visual acuity, anterior and posterior segment examinations, and macular optical coherence tomography were unremarkable. Electroretinogram (ERG) testing revealed a rod-cone dystrophic pattern, with further workup demonstrating serum vitamin A deficiency (VAD). Laboratory evaluation revealed renal dysfunction and proteinuria with a significantly elevated urinary retinol-binding protein (RBP). Kidney biopsy showed glomerular and tubular disease.Genetic screening for inherited renal disease was performed identifying a hemizygous pathogenic variant c.2152C>T (p.Arg718*) in the Chloride Voltage-Gated Channel 5 (CLCN5) gene, confirming the diagnosis of X-linked Dent Disease. Following vitamin A supplementation, our patient reported resolution of nyctalopia and reversal of abnormal ERG findings were demonstrated. Conclusions and Importance: To our knowledge, this is the first case in the literature describing Dent disease solely presenting with ophthalmic symptoms of nyctalopia and abnormal electroretinogram findings that later reversed with vitamin A repletion. This case stresses the importance for clinicians to consider renal tubular disorders in the differential for VAD.

Optic Nerve Aplasia.

OBJECTIVE: Optic nerve aplasia (ONA) is a rare ocular anomaly. We report ophthalmologic, systemic, and genetic findings in ONA. METHODS: Patients were identified through an International Pediatric Ophthalmology listserv and from the practice of the senior author. Participating Listserv physicians completed a data collection sheet. Children of all ages were included. Neuroimaging findings were also recorded. RESULTS: Nine cases of ONA are reported. Patients' ages ranged from 10 days to 2 years (median 9 months). Seven cases were bilateral. All patients had absence of the optic nerve and retinal vessels in the affected eye or eyes. Ophthalmologic findings included glaucoma, microcornea, persistent pupillary membrane, iris coloboma, aniridia, retinal dysplasia, retinal atrophy, chorioretinal coloboma, and persistent fetal vasculature. Systemic findings included facial dysmorphism, cardiac, genitourinary, skeletal, and developmental defects. A BCOR mutation was found in one patient. One patient had rudimentary optic nerves and chiasm on imaging. CONCLUSION: ONA is a unilateral or bilateral condition that may be associated with anomalies of the anterior or posterior segment with or without systemic findings. Rudimentary optic nerve on neuroimaging in one case suggests that ONA is on the continuum of optic nerve hypoplasia.

Anterior Segment Optical Coherence Tomography in Locating the Insertion of Horizontal Extraocular Muscles After Strabismus Surgery.

PURPOSE: To evaluate the accuracy of anterior segment optical coherence tomography (AS-OCT) for locating horizontal extraocular muscle (EOM) insertion after strabismus surgery. METHODS: The distance from the limbus to the postoperative muscle insertion was measured with calipers intraoperatively and by AS-OCT during the postoperative visit of adults undergoing strabismus surgery. Images were collected by masked technicians. Intraclass correlation coefficients (ICC) were used to evaluate the agreement between measurements. RESULTS: Twenty-eight patients were recruited. Measurements were taken from 31 eyes, including 17 lateral and 14 medial rectus muscles. EOM insertion was successfully identified by AS-OCT for 14 (45%) cases. The ICC between intra-operative and AS-OCT measurement was 0.886 when the distance from the limbus to the insertion of EOM was less than 8 mm and 0.001 when the distance from the limbus was between 8 and 10 mm. EOM insertion was undetectable if distance to the limbus was greater than 10 mm. CONCLUSIONS: AS-OCT can accurately identify post-surgical horizontal muscle insertion if the insertion is less than 8 mm from the limbus. [J Pediatr Ophthalmol Strabismus. 2021;58(1):62-65.].

Treatment of Port Wine Birthmarks in Sturge-Weber Syndrome Using Topical Timolol.

Three patients with facial port wine birthmarks were randomly assigned to receive treatment with topical timolol or the placebo. Three masked observers evaluated photographs of the patients, noting improvement in patients who were treated with timolol and two controls. The photographic technique was not standardized. This pilot study suggests topical timolol warrants further evaluation for port wine birthmarks. [J Pediatr Ophthalmol Strabimus. 2021;58:e1-e4.].

Strabismus Surgery Infection Prophylaxis and Timing of First Postoperative Visit.

PURPOSE: To characterize the practice patterns of pediatric ophthalmologists regarding infection prophylaxis for strabismus surgery and timing of the first postoperative visit. METHODS: A ten-question multiple-choice, close-ended questionnaire was e-mailed to members of the American Association for Pediatric Ophthalmology and Strabismus listserv. Survey responses were summarized using frequencies and percentages. Univariable tests of association between prophylactic measures and surgeons reporting a prior episode of postoperative cellulitis or endophthalmitis were performed. RESULTS: Three hundred eighty pediatric ophthalmologists completed the survey. Most ophthalmologists instill 5% povidone-iodine solution during surgical preparation (88.4%), use topical antibiotics with or without steroids at the conclusion of surgery (90%), and prescribe oral or topical antibiotics postoperatively (85.5%). Eighty-five percent of strabismus surgeons routinely see patients for the first postoperative visit within the first week, although there is no consensus as to which day is preferred. Responders previously reporting experience with a postoperative infection were more likely to use intraoperative intravenous antibiotics (P = .002) and Tegaderm tape (3M, St. Paul, MN) or other adhesive drape to isolate the eyelids/eyelashes (P = .047). CONCLUSIONS: A common practice pattern appears to exist regarding the use of 5% povidone-iodine solution in surgical preparation, application of topical antibiotics at the end of surgery, and a postoperative regimen of topical antibiotics/steroids. There is no prevailing practice pattern regarding the timing of the first postoperative visit. Previous experience with postoperative cellulitis or endophthalmitis may lead to the adoption of more formidable infection prophylaxis measures such as intravenous antibiotics prior to surgery. [J Pediatr Ophthalmol Strabismus. 2019;56(6):354-359.].