Peripapillary vessel density in eyes with cone-rod dystrophy.

PURPOSE: To compared the vessel density (VD) around the optic nerve head (ONH) in eyes with cone-rod dystrophy (CORD) and healthy control eyes in a sector-wise manner and to investigate the relationship between VD around the ONH and visual function in CORD eyes. METHODS: Twenty-six eyes in 14 CORD patients and 25 eyes in 25 healthy control subjects were examined. Using OCT angiography images, the VDs in the superficial and deep capillary plexus at the macula (sVDm and dVDm) and those around the ONH in the superior, temporal, inferior and nasal region (VDnh_s, VDnh_t, VDnh_i, and VDnh_n, respectively) were measured for each eye. Patient age, visual acuity (VA) and VDs were then compared between two groups. Moreover, the relationships between VA and the VDs were analyzed using a linear mixed model and AICc model selection. RESULTS: No significant difference in age was seen between the CORD and control groups (p = 0.87, Wilcoxon rank sum test), but the VA was significantly lower in the CORD group (p<0.0001). Both sVDm and dVDm were significantly lower in the CORD eyes than in the control eyes (both p<0.0001). Among VDnh_s, VDnh_t, VDnh_i, and VDnh_n, however, only VDnh_t differed significantly between the CORD and control groups (p = 0.035). Among age, VDnh_t, dVDm, and sVDm, the optimal model for VA included only VDnh_t and dVDm. CONCLUSIONS: In addition to the VD in the deep capillary plexus at the macula, the measurement of temporal VD around the ONH might be useful for predicting visual function in eyes with CORD.

Predictive factors for postoperative visual function in eyes with epiretinal membrane.

Our current study aimed to investigate the association of preoperative OCT parameters with visual function after vitrectomy surgery in eyes with epiretinal membrane (ERM). This study enrolled 33 eyes with ERM that underwent vitrectomy surgery. In addition to visual acuity (VA), metamorphopsia was measured pre- and postoperatively for each eye. Using the preoperative horizontal and vertical OCT images, SUKIMA (the gap area between the ERM and retinal surface) was measured respectively and the average of horizontal SUKIMA and vertical SUKIMA was used for the analysis. The associations of baseline parameters (age, axial length, preoperative central retinal thickness [CRT], inner nuclear layer [INL] thickness, ectopic inner foveal layer [EIFL] and SUKIMA) with postoperative VA, the change in VA, postoperative metamorphopsia and the improvement in metamorphopsia were investigated using multivariate regression analysis followed by the model selection. The result suggested that age and INL thickness were related to the postoperative VA, whereas age and preoperative CRT were significantly associated with the change in VA. In contrast, only SUKIMA was correlated with the postoperative metamorphopsia, whilst age, EIFL and SUKIMA were associated with the improvement in metamorphopsia. Measuring SUKIMA might be useful for predicting postoperative metamorphopsia and the improvement in metamorphopsia in ERM eyes.

IMPACT OF GAS/AIR TAMPONADE ON REFRACTIVE OUTCOMES AFTER FLANGED INTRASCLERAL INTRAOCULAR LENS FIXATION.

PURPOSE: This study aims to investigate the postoperative refractive outcomes in eyes that underwent the flanged intrascleral intraocular lens (IOL) fixation combined with vitrectomy with or without gas/air tamponade. METHODS: The eyes were divided into two groups (Group A; eyes that underwent flanged intrascleral IOL fixation with gas/air tamponade, and Group B; eyes that underwent flanged intrascleral IOL fixation without gas/air tamponade). The predicted spherical equivalent (SE) refraction values were calculated using the Sander-Retzlaff-Kraff Theoretical formula. Then, the prediction error was calculated by subtracting the predicted SE refraction from the postoperative objective SE refraction and the absolute prediction error was calculated as the absolute value of the prediction error for each eye. RESULTS: A total of 68 eyes were included in the current study. There was a significant correlation between the predicted and postoperative SE refraction in both groups (Group A, r = 0.968, P < 0.0001, Group B, r = 0.943, P < 0.0001, linear regression analysis). The prediction error demonstrated a mild myopic shift after the flanged intrascleral IOL fixation in both groups (Group A, -0.40 ± 0.96 diopter, Group B, -0.59 ± 0.95 diopter). There was no significant difference in prediction error and absolute prediction error between the two groups ( P = 0.44, P = 0.70, Wilcoxon rank sum test). CONCLUSION: The postoperative SE refraction after flanged intrascleral IOL fixation was not influenced by gas/air tamponade.

EVALUATION OF THE RETINAL HAZARD WITH 3D DIGITALLY ASSISTED VISUALIZATION SYSTEM AND CONVENTIONAL MICROSCOPE IN MACULAR SURGERIES.

PURPOSE: To investigate the retinal light hazard during macular surgery using a digital three-dimensional visualization system (3D) and a conventional microscope (CM). DESIGN: Experimental study and retrospective evaluation of a case-control study. SUBJECTS: A total of 20 and 10 patients who underwent pars plana vitrectomy for epiretinal membrane using 3D and CM, respectively. METHODS: Spectral irradiances of endoilluminators were measured for representative settings used during core vitrectomy and macular manipulations with 3D and CM. From the medical record of the patients, time needed for core vitrectomy and macular manipulations was extracted. The total retinal light hazard index and the macular hazard index were calculated based on the spectral irradiances weighted by the standard functions. Total retinal light hazard index, macular hazard index, and the number of cases that exceeded the maximum permissible radiant power exposure were compared between the two groups. RESULTS: The spectral irradiance were 1.6 and 3.9 mW/cm 2 for core vitrectomy and 3.4 and 8.1 mW/cm 2 for macular manipulations using typical settings for 3D and CM groups, respectively. The total retinal light hazard index ranged from 4.31 kJ/m 2 to 17.37 kJ/m 2 for 3D and 11.09 kJ/m 2 to 27.70 kJ/m 2 for CM groups, respectively, whereas the macular hazard index ranged from 2.93 kJ/m 2 to 14.58 kJ/m 2 for 3D and from 6.84 kJ/m 2 to 23.55 kJ/m 2 for CM, respectively ( P < 0.001). One (5%) and 6 (60%) pars plana vitrectomy cases exceeded the threshold limits with 3D and CM groups, respectively ( P < 0.05, chi-square test). CONCLUSION: The 3D digitally assisted visualization system offers significantly safer macular surgery compared with the CM, considering the potential retinal hazard.