Choroidal Morphologic and Vascular Features in Patients With Myopic Choroidal Neovascularization and Different Levels of Myopia Based on Image Binarization of Optical Coherence Tomography

Purpose: To characterize the choroidal morphologic and vascular features in different levels of myopes and patients with myopic choroidal neovascularization (mCNV).Methods: A total of 148 subjects were enrolled in this cross-sectional study, including 78 low-to-moderate myopes (LMM), 53 high myopes (HM), and 17 high myopic patients with mCNV. Ocular biometrics were measured using an optical low-coherence reflectometry device. Retinal and choroidal imaging was performed using enhanced depth imaging (EDI) spectral domain optical coherence tomography (OCT). Retinal parameters including retinal thickness and retinal volume were obtained from a built-in software. Binarization technique was adopted to investigate choroidal parameters including choroidal thickness (CT), vascular area, stromal area, and choroidal vascularity index (CVI). Choroidal parameters were measured at five locations to cover as much area of choroid as possible, and their patterns of distribution were further analyzed.Results: Patients with mCNV had an atrophic retina of comparable thickness to HM (273.65 ± 17.28 vs. 276.49 ± 13.29 μm, p = 0.47), but the choroid was thinner than that of HM (153.94 ± 15.12 vs. 236.09 ± 38.51 μm, p < 0.001). Subfoveal CVI was greatest in the mCNV eyes (0.651 ± 0.009), followed by HM (0.645 ± 0.012) and LMM eyes (0.636 ± 0.012). Similar to CT, CVI was also found significantly different among these three groups at all five locations (p for trend < 0.001 for all locations). Axial length (AL) was negatively correlated with retinal volume (r = −0.236, p = 0.009), which is the only significant finding in associations between ocular factors and retinal parameters. Strong, negative correlations were identified between AL and subfoveal choroidal thickness (SFCT, r = −0.820, p < 0.001). However, AL was positively correlated with subfoveal CVI (r = 0.668, p < 0.001). CVI was greater in myopic eyes with thinner choroid (r = −0.578, p < 0.001). BCVA exhibited no significant association with CVI (r = 0.139, p = 0.092), but was negatively correlated with SFCT (r = −0.386, p < 0.001) and positively correlated with AL (r = 0.351, p < 0.001).Conclusion: Choroid in patients with mCNV was thinner yet more vascularized than that in HM and LMM subjects. CVI increased with a longer AL which was associated with a smaller SFCT, choroidal vascular area (VA), and total choroidal area (TCA). Better BCVA was achieved in subjects with thicker SFCT and shorter AL.

Thickness of the choroid, ciliary body and retina according to optical coherence tomography in patients after Femto LASIK

Background. In the available literature, there are isolated publications devoted to the topic of the possible effect of laser correction by the Femto LASIK method on the myopic eye choroid. In this connection, in our opinion, the relevance of continuing research in this direction remains.The aim of this study was to examine the volume of the retina in the macular zone, the thickness of the choroid and the ciliary body using optical coherence tomography on myopic eyes after femtosecond-assisted laser in situ keratomileusis in the short term.Material and methods. 30 patients (30 right eyes) aged 20 to 35 years, suffering from mild and moderate myopia, but without pathological changes in the retina according to OCT, made up the study group. All patients underwent myopia correction using the Femto LASIK method. Before the operation, after 4 hours and the next day, they underwent the examination of the retinal volume in the macular zone, the choroidal and the ciliary body thickness using OCTResults. The analysis of the obtained results of the studied parameters showed that the ciliary body thickness and the retinal volume in the macular zone did not undergo statistically signifi cant changes and remained within the preoperative values (p > 0.05). We observed a tendency to an increase in the thickness of the choroid 4 hours after the operation, but the carried out statistical analysis did not confi rm the reliability of its changes (p > 0.05). On the next day, the choroidal thickness indices practically recovered to the preoperative level (p > 0.05).Conclusion. A study of the retinal volume in the macular zone, the thickness of the choroid and ciliary body using OCT in myopic eyes in the short term after Femto LASIK showed the absence of statistically signifi cant changes in the studied parameters, which indirectly indicates the safety of this method of laser correction for the posterior segment of the eye.

Comparison between blue-on-yellow and white-on-white perimetry in patients with branch retinal vein occlusion

This study aimed to compare blue-on-yellow (B/Y) perimetry with white-on-white (W/W) perimetry in eyes with branch retinal vein occlusion (BRVO). The following measurements were performed in 29 eyes of 29 patients with resolved BRVO: W/W and B/Y perimetries using 10-2 test grid, retinal volume (RV) using optical coherence tomography (OCT), and vessel densities (VD) of the superficial capillary layer (VDs) and deep capillary layer (VDd) using OCT angiography (OCTA). First, the difference in the retinal sensitivity (RS) between BRVO-affected and unaffected areas was compared between RS_B/Y and RS_W/W in the parafoveal and extrafoveal areas. Moreover, the structure–function relationship between vessel density and RS was compared between B/Y and W/W perimetries (RS_B/Y and RS_W/W, respectively). The difference in RS between BRVO-affected and unaffected areas was significantly larger with RS_B/Y than with RS_W/W in both the parafoveal and extrafoveal areas. In the parafoveal area, VDs, VDd, and RV were significantly correlated with both RS_W/W and RS_B/Y. In contrast, in the extrafoveal area, only VDd was included in the optimal models. Our findings suggest that RS_B/Y more strongly reflects the anatomical structure and BRVO-affected area.

Short-term effect of intravitreal conbercept injection on major and macular branch retinal vein occlusion

Objective To evaluate the effectiveness of intravitreal conbercept injection on major and macular branch retinal vein occlusion (BRVO). Methods This retrospective analysis involved 43 patients with BRVO (major BRVO n = 24; macular BRVO, n = 19) who were diagnosed by fluorescein fundus angiography (FFA) and injected with intravitreal conbercept. The following outcomes were measured at baseline and follow-up (1-6 months): best-corrected visual acuity (BCVA), central foveal thickness (CFT), total retinal volume in a 6-mm diameter section of the macula, choroidal thickness under the central fovea of the macula, relative area of retinal hemorrhage, complications, and times when repeated injection was performed. Results There were significant differences between the two groups in terms of BCVA, CFT, and total retinal volume in a 6-mm diameter section of the macula at 6 months after treatment. Choroidal thickness under the central fovea of the macula and relative area of retinal hemorrhage showed no significant differences between the two groups at 6 months after treatment; however, they significantly differed from baseline measurements. Conclusion In general, intravitreal injection of conbercept may have a better short-term effect in patients with macular BRVO than in patients with major BRVO.