DISCREPANCY BETWEEN FUNDUS AUTOFLUORESCENCE ABNORMALITY AND VISUAL FIELD LOSS IN BIETTI CRYSTALLINE DYSTROPHY.

PURPOSE: The aim of this study was to explore the potential benefits of retinal pigment epithelium replacement therapy in patients with Bietti crystalline dystrophy (BCD) by assessing the disease pathology with the distinctive relationship between fundus autofluorescence (FAF) abnormality and visual field defect. METHODS: Sixteen eyes from 16 patients with BCD and 16 eyes from 16 patients with RHO-associated retinitis pigmentosa were included. Fundus autofluorescence, optical coherence tomography, and Goldmann perimetry results were retrospectively reviewed and assessed using image analyses. RESULTS: In patients with BCD, the FAF abnormality area was not correlated with the overall visual field defect area and median overall visual field defect area (57.5%) was smaller than FAF abnormality area (98.5%). By contrast, the ellipsoid zone width was significantly correlated with the central visual field area (r = 0.806, P < 0.001). In patients with RHO-associated retinitis pigmentosa, the FAF abnormality area and ellipsoid zone width were significantly correlated with the overall visual field defect area (r = 0.833, P < 0.001) and central visual field area (r = 0.887, P < 0.001), respectively. CONCLUSION: The FAF abnormality shown in patients with BCD involves retinal pigment epithelium degeneration without complete loss of photoreceptors or visual function. These results suggest that patients with BCD are good candidates for retinal pigment epithelium replacement therapy for preservation of residual visual function.

Adaptive Optics Optical Coherence Tomography Analysis of Induced Pluripotent Stem Cell-Derived Retinal Organoid Transplantation in Retinitis Pigmentosa.

This study evaluates the transplantation of induced pluripotent stem cell (iPSC)-derived retinal organoids into patients with advanced retinitis pigmentosa using adaptive optics optical coherence tomography (AO-OCT) to monitor retinal changes over two years post transplantation. Our results confirmed successful engraftment and increased retinal thickness, with AO-OCT providing detailed visualization of cellular structures such as an outer plexiform layer-like line and highly reflective particles within rosette-like formations, indicative of photoreceptor development. Immunohistological analysis in a parallel monkey model confirmed these structures as mature, functional photoreceptor rosettes. The integration of high-resolution AO-OCT with immunohistology provides critical insights into the structural and functional outcomes of transplantation and represents a promising advancement in the treatment of retinal degenerative diseases.

Evaluation of photoreceptor features in retinitis pigmentosa with cystoid macular edema by using an adaptive optics fundus camera.

OBJECTIVE: Cystoid macular edema (CME) in retinitis pigmentosa (RP) is an important complication causing visual dysfunction. We investigated the effect of CME on photoreceptors in RP patients with previous or current CME, using an adaptive optics (AO) fundus camera. METHODS: We retrospectively observed the CME and ellipsoid zone (EZ) length (average of horizontal and vertical sections) by optical coherence tomography. The density and regularity of the arrangement of photoreceptor cells (Voronoi analysis) were examined at four points around 1.5° from superior to inferior and temporal to nasal. We also performed a multivariate analysis using CME duration, central macular thickness and transversal length of CME. RESULTS: We evaluated 18 patients with previous or current CME (18 eyes; age, 48.7 ± 15.6 years) and 24 patients without previous or current CME (24 eyes; age, 46.0 ± 14.5 years). There were no significant differences in age, logMAR visual acuity, or EZ length. In groups with and without CME, cell density was 11967 ± 3148 and 16239 ± 2935 cells/mm2, and sequence regularity was 85.5 ± 3.4% and 88.5 ± 2.8%, respectively; both parameters were significantly different. The correlation between photoreceptor density and age was more negative in group with CME. The CME group tended toward greater reductions in duration of CME. CONCLUSION: Complications of CME in RP patients may lead to a decrease in photoreceptor density and regularity. Additionally, a longer duration of CME may result in a greater reduction in photoreceptor density.

Relationship between residual visual field and full-field stimulus testing in patients with late-stage retinal degenerative diseases.

This study aimed to investigate how the extent and central/peripheral location of the residual visual field (VF) in patients with late-stage inherited retinal diseases (IRDs) are related to retinal sensitivity detected using full-field stimulus testing (FST). We reviewed the results of Goldmann perimetry and FST from the medical records of patients with IRDs whose VF represents central (within 10°) and/or peripheral islands, or undetectable. In total, 19 patients (19 eyes) were analyzed in this study. The median value of residual VF area was 1.38%. The median values of rod and cone sensitivities were - 14.9 dB and 7.4 dB, respectively. Patients with only the peripheral island (- 33.9 dB) had better median rod sensitivity than other groups (only central, - 18.9 dB; both, - 3.6 dB). VF area significantly correlated with rod sensitivity (r = - 0.943, p = 0.005) in patients with only peripheral island, but not with cone sensitivity. Peripheral VF islands were significant contributors to FST results, especially rod sensitivity. With reduced or loss of central vision, the extent of residual peripheral VF significantly affected rod sensitivity, suggesting that FST can be useful in quantitatively estimating the overall remaining vision in patients with late-stage IRD.

Copy number variant detection using next-generation sequencing in EYS-associated retinitis pigmentosa.

Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy and a major cause of blindness. RP is caused by several variants of multiple genes, and genetic diagnosis by identifying these variants is important for optimizing treatment and estimating patient prognosis. Next-generation sequencing (NGS), which is currently widely used for diagnosis, is considered useful but is known to have limitations in detecting copy number variations (CNVs). In this study, we re-evaluated CNVs in EYS, the main causative gene of RP, identified via NGS using multiplex ligation-dependent probe amplification (MLPA). CNVs were identified in NGS samples of eight patients. To identify potential CNVs, MLPA was also performed on samples from 42 patients who were undiagnosed by NGS but carried one of the five major pathogenic variants reported in Japanese EYS-RP cases. All suspected CNVs based on NGS data in the eight patients were confirmed via MLPA. CNVs were found in 2 of the 42 NGS-undiagnosed RP cases. Furthermore, results showed that 121 of the 661 patients with RP had EYS as the causative gene, and 8.3% (10/121 patients with EYS-RP) had CNVs. Although NGS using the CNV calling criteria utilized in this study failed to identify CNVs in two cases, no false-positive results were detected. Collectively, these findings suggest that NGS is useful for CNV detection during clinical diagnosis of RP.