Objective and quantitative estimation of the optimal timing for epiretinal membrane surgery on the basis of metamorphopsia

Purpose: To establish an objective and quantitative biomarker of metamorphopsia in epiretinal membranes (ERMs) and determine the optimal timing for ERM surgery. Methods: Retrospectively, 172 eyes with ERM were reviewed. Retinal folds due to tangential traction by ERM were visualized by en face optical coherence tomography (OCT). The maximum depth of retinal folds (MDRF) within the parafovea was quantified. Metamorphopsia was quantified by M-CHARTS. The change in the distance between the retinal vessels after ERM surgery and the preoperative total depth of retinal folds between the vessels were quantified using en face OCT and OCT angiography. Results: Significant correlations were observed between preoperative MDRF and M-CHARTS scores before and at 6 months after surgery (r=0.617 and 0.460, respectively; P Conclusion: MDRF is an objective and quantitative biomarker of metamorphopsia in ERM. To maintain patients’ quality of vision, ERM surgery may be performed when the preoperative MDRF ranges between 69 and 118 μm

Assessment of epiretinal membrane formation using en face optical coherence tomography after rhegmatogenous retinal detachment repair

Purpose　To investigate epiretinal membrane (ERM) formation using en face optical coherence tomography (OCT) after vitrectomy for rhegmatogenous retinal detachment (RRD). Methods　We retrospectively reviewed the medical records of 64 consecutive eyes (64 patients) with RRD treated by vitrectomy without ERM and internal limiting membrane peeling. ERMs and retinal folds were detected by B-scan and en face imaging. The maximum depth of retinal folds (MDRF) was quantified using en face imaging. ERM severity was staged using B-scan imaging. Main outcome measures were ERM detection rate with B-scan and en face imaging, MDRF, ERM staging, postoperative best-corrected visual acuity (BCVA; logarithm of the minimum angle of resolution), and risk factors for ERM formation. Results　The detection rate for ERM formation was significantly higher with en face imaging (70.3%) than with B-scan imaging (46.9%; P = 0.007). There was no significant difference in postoperative BCVA between eyes with ERM formation (0.06 ± 0.26) and those without ERM formation (0.01 ± 0.14; P = 0.298). Forty of 45 (88.9%) eyes with ERM formation were classified as stage 1. Twenty-seven of 45 (60.0%) eyes with ERM formation developed parafoveal retinal folds. The mean MDRF was 27.4 ± 32.2 μm. Multiple retinal breaks and a maximum retinal break size of ≥ 2 disc diameters were significantly associated with ERM formation (P = 0.033 and P = 0.031, respectively). Conclusion　Although ERM formation was observed in 70.3% patients after RRD repair, the formed ERM was not severe and had minimal impact on the postoperative visual acuity

KCNJ13 Gene Deletion Impairs Cell Alignment and Phagocytosis in Retinal Pigment Epithelium Derived from Human-Induced Pluripotent Stem Cells

Purpose: The purpose of this study was to establish and analyze a cell model of Leber congenital amaurosis type 16 (LCA16), which is caused by mutations in the KCNJ13 gene encoding Kir7.1, an inward-rectifying potassium ion channel. Methods: The two guide RNAs specific to the target sites in the KCNJ13 gene were designed and KCNJ13 knock-out (KO) human-induced pluripotent stem cells (hiPSCs) were generated using the CRISPR/Cas9 system. The KCNJ13-KO hiPSCs were differentiated into retinal pigment epithelial cells (hiPSC-RPEs). The KCNJ13-KO in hiPSC-RPEs was confirmed by immunostaining. Phagocytic activity of hiPSC-RPEs was assessed using the uptake of fluorescently labeled porcine photoreceptor outer segments (POSs). Phagocytosis-related genes in RPE cells were assessed by quantitative polymerase chain reaction. Results: Most of the translated region of the KCNJ13 gene was deleted in the KCNJ13-KO hiPSCs by the CRISPR/Cas9 system, and this confirmed that the Kir7.1 protein was not present in RPE cells induced from the hiPSCs. Expression of RPE marker genes such as BEST1 and CRALBP was retained in the wild-type (WT) and in the KCNJ13-KO hiPSC-RPE cells. However, phagocytic activity and expression of phagocytosis-related genes in the KCNJ13-null hiPSC-RPE cells were significantly reduced compared to those of WT. Conclusions: We succeeded in generating an RPE model of LCA16 using hiPSCs. We suggest that Kir7.1 is required for phagocytosis of POSs by RPE cells and that impaired phagocytosis in the absence of Kir7.1 would be involved in the retinal degeneration found in LCA16

Bilateral Blunt Ocular Trauma Caused by an Exercise Resistance Band during Muscle Building Exercise for Swimming

An 18-year-old male high school student presented to our clinic with bilateral blunt ocular trauma caused by an exercise resistance band (ERB) during a muscle-building exercise. Best-corrected decimal visual acuities (BCVAs) for right and left eyes were light perception and 0.15, respectively. The right eye was operated 10 days after injury for persistent vitreous hemorrhage, and the left eye 5 months later because of macular hole onset. After 36 months, the right eye showed extensive retinal degeneration (BCVA 0.04), and the left eye macular hole closure (BCVA 1.2). ERBs should be used cautiously as they can cause serious ocular trauma

En face image-based classification of diabetic macular edema using swept source optical coherence tomography

This retrospective study was performed to classify diabetic macular edema (DME) based on the localization and area of the fluid and to investigate the relationship of the classification with visual acuity (VA). The fluid was visualized using en face optical coherence tomography (OCT) images constructed using swept-source OCT. A total of 128 eyes with DME were included. The retina was segmented into: Segment 1, mainly comprising the inner nuclear layer and outer plexiform layer, including Henle's fiber layer; and Segment 2, mainly comprising the outer nuclear layer. DME was classified as: foveal cystoid space at Segment 1 and no fluid at Segment 2 (n=24), parafoveal cystoid space at Segment 1 and no fluid at Segment 2 (n=25), parafoveal cystoid space at Segment 1 and diffuse fluid at Segment 2 (n=16), diffuse fluid at both segments (n=37), and diffuse fluid at both segments with subretinal fluid (n=26). Eyes with diffuse fluid at Segment 2 showed significantly poorer VA, higher ellipsoid zone disruption rates, and greater central subfield thickness than did those without fluid at Segment 2 (P<0.001 for all). These results indicate the importance of the localization and area of the fluid for VA in DME

Embedding of Epiretinal Proliferation for a Secondary Lamellar Macular Hole 12 Years after Rhegmatogenous Retinal Detachment Repair

A 58-year-old Japanese man underwent vitrectomy for rhegmatogenous retinal detachment (RRD) in 2002. Twelve years later, optical coherence tomography revealed the development of a lamellar macular hole; the visual acuity was 20/200. Two years later, because metamorphopsia and the foveal retina thinning were aggravated, epiretinal proliferation embedding was performed to restore the foveal structure by transplanting glial cells to the foveal cavity. The patient was followed-up for 4 years, and his macular morphology and visual acuity (20/66) improved. No complications occurred. This appears to be the first report of epiretinal proliferation embedding for a lamellar macular hole post-RRD repair

Sublingual Gland Carcinoma Revealed by Choroidal Metastasis

A 65-year-old man presented with a 1-week history of left eye distortion. An elevated choroidal lesion covering 6 disc diameters was found in the posterior retina of the left eye. Systemic examination revealed sublingual gland carcinoma and multiple lung metastases, and the diagnosis was choroidal metastasis from sublingual gland carcinoma. Following chemotherapy and radiation therapy, the choroidal lesion shrunk and the patient’s visual acuity improved. The patient died 23 months after his first visit. To the best of our knowledge, this is the first reported case of choroidal metastasis from sublingual gland carcinoma

Effect of rhegmatogenous retinal detachment on preoperative and postoperative retinal sensitivities

This retrospective study investigated foveal and perifoveal retinal sensitivities using microperimetry before and after surgery for rhegmatogenous retinal detachment (RRD). Consecutive patients with RRD who underwent vitrectomy or scleral buckling were included. Comprehensive ophthalmological examinations, including microperimetry and swept-source optical coherence tomography, were performed before and 6 months after surgery. Pre- and postoperative retinal sensitivities at the fovea and 4 perifoveal measurement points farthest from the fixation point, both vertically and horizontally (superior, inferior, nasal, and temporal) were examined. A total of 34 foveal and 136 perifoveal measurement points in 34 eyes of 34 patients were evaluated. The postoperative retinal sensitivity was significantly higher than the preoperative value at foveal and perifoveal points with (P<0.001 for both) and without (fovea: P=0.005, perifovea: P<0.001) RRD. The postoperative retinal sensitivity was significantly lower at foveal (P<0.01) and perifoveal (P<0.001) points with preoperative RRD than at points without preoperative RRD; furthermore, it was significantly better at points with ellipsoid zone (Ez) continuity than at points with Ez discontinuity (fovea: P<0.01, perifovea: P<0.001). RRD deteriorates retinal sensitivity, regardless of its presence or absence at the measurement point before surgery. Postoperative Ez continuity is important for good postoperative retinal sensitivity

A case of Bickerstaff's brainstem encephalitis in childhood

Bickerstaff&#38;apos&#59;s brainstem encephalitis (BBE) is a rare disease diagnosed by specific clinical features such as &#38;apos&#59;progressive, relatively symmetric external ophthalmoplegia and ataxia by 4 weeks&#38;apos&#59; and &#38;apos&#59;disturbance of consciousness or hyperreflexia&#38;apos&#59; after the exclusion of other diseases involving the brain stem. Anti-ganglioside antibodies (GM, GD and GQ) in the serum or cerebrospinal fluid (CSF) are sometimes informative for the diagnosis of BBE because of the rarity of positive findings in other diagnositic methods: brain magnetic resonance imaging (MRI), routine CSF examination, motor nerve conduction study, and needle electromyography. We report a rare case of childhood BBE with elevated anti-GM1 antibodies in the serum, who had specific clinical symptoms such as a cranial polyneuropathy presenting as ophthalmoplegia, dysarthria, dysphagia, and facial weakness&#59; progressive motor weakness&#59; altered mental status&#59; and ataxia. However, the brain MRI, routine CSF examination, nerve conduction studies, electromyography, somatosensory evoked potentials, and brainstem auditory evoked potentials were normal. BBE was suspected and the patient was successfully treated with intravenous immunoglobulins