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.

Myopic choroidal neovascularization: management issues remain

In the modern world, myopia continues to be one of the most common refractive errors and is considered a socially signifi cant problem, since it is a common cause of decreased vision. In connection with the growth of myopia, the risk of developing complications in the fundus increases, leading to the development of degenerative changes in the retina and an irreversible decrease in visual functions in young and middle-aged people. One of these complications is myopic choroidal neovascularization, which leads to a progressive, irreversible decrease in visual acuity and poor prognosis, and the process is often bilateral in nature. The tactics of managing patients with such complications has been determined: antiangiogenic therapy is used – intravitreal therapy with anti-VEGF drugs, which is currently the fi rst choice therapy for this pathology. But in some cases, antiangiogenic therapy is contraindicated, and the question arises about the tactics of managing such patients. The aim: to study treatment options for myopic choroidal neovascularization in patients with myopia in different situations.Material and methods. The paper presents two clinical observations of patients with mChNV, considers the tactics of their management. The patients underwent standard ophthalmological examination, optical coherence tomography (OCT) and OCT-Angio (OPTOPOL Technology, Poland).Conclusions. Women with myopia planning pregnancy need a thorough examination not only by a clinician, but also by an ophthalmologist, since it is necessary to take into account not only the degree of myopia and choose the optimal delivery method, but also to study the state of the retina for the timely diagnosis of degenerative changes in the fundus.

Result of intravitreal aflibercept injection for myopic choroidal neovascularization

Background The current study aimed to evaluate the efficacy of intravitreal aflibercept injections as the primary treatment for subfoveal/juxtafoveal myopic choroidal neovascularization (CNV) by using optical coherence tomography (OCT). Optical coherence tomography angiography (OCTA) was further used for some patients to detect the changes of CNV after treatment. Methods In the present study, 21 treatment-naive eyes of 21 patients with subfoveal/juxtafoveal myopic CNV received primary intravitreal aflibercept injections and were under follow-up for a minimum duration of 12 months. Among the 21 patients, 12 underwent OCTA to evaluate the changes in central foveal thickness, selected CNV area, and flow area. Results The mean best-corrected visual acuity (BCVA) pertaining to all the patients significantly improved from the baseline value of 0.7 to 0.3 logMAR after treatment for 12 months (P = 0.001). However, the improvements in the median BCVA after treatment for three and 12 months were not statistically significant in the younger group (< 50 years), compared to the older group (≥ 50 years). One aflibercept injection resolved the CNV in 47.6% (10/21) of the patients. The younger group displayed greater improvement in the median central foveal thickness, compared to the older group. OCTA revealed interlacing or disorganized pattern at the level of the outer retinal layer in 12 subjects with myopic CNV. After 3 months of treatment, both groups displayed a decrease in the size of the selected CNV area and flow area. The interlacing group displayed a trend towards better anatomical improvements. Conclusion Intravitreal aflibercept injection provides long-term improvement in visual acuity in patients with myopic CNV. Eyes with the interlacing pattern on OCTA displayed a greater decrease in size and flow after aflibercept injection. Trial registration Before data collection, written informed consent was obtained from each participant, whose identity information was protected by encryption and conversion to a non-identifiable format and removing data links. This study was approved by the Institutional Review Board of Kaohsiung Veterans General Hospital (KSVGH21-CT1–17).

Macular density alterations in myopic choroidal neovascularization and the effect of anti-VEGF on it

AIM: To analyse macular microvascular alterations in myopic choroidal neovascularization (mCNV) and the efficiency of anti-vascular endothelial growth factor (anti-VEGF) therapy for mCNV by optical coherence tomography angiography (OCTA). METHODS: A total of 123 patients were included in this retrospective study, divided into mCNV group, high myopia (HM) group, and normal group at the Affiliated Eye Hospital of Wenzhou Medical University from January 2017 to January 2019. Superficial vessel density, deep capillary density, foveal avascular zone (FAZ) area, A-circularity index (AI) and vessel density around the 300 μm width of the FAZ region density (FD) and the area of choroidal neovascularization (CNV) lesion (only for mCNV group) were measured on 3×3 mm2 OCTA images. FAZ area was corrected for axial length. Central macular thickness (CMT) was measured on OCT in mCNV group. Compared the parameters on OCTA of 3 groups and pre-anti-VEGF and post-anti-VEGF at 1, 2, 3, and 6mo follow-up in mCNV group. RESULTS: There were significant differences among 3 groups in superficial vessel density, deep capillary density and FD (P<0.05). FAZ area in HM group was smaller than normal group (P<0.05), but there was no significant difference between mCNV group and the other two group. AI increased in mCNV group (P<0.05). The mean CMT, area and flow area of CNV lesion decreased after treatment (P<0.05), while vessel density and FAZ didn’t change. The mean CMT, area and flow area of CNV lesion statistically decreased after anti-VEGF treatment in mCNV group (P<0.05), while superficial vessel density, deep capillary density and FAZ area, AI and FD didn’t change. The mean reduction ratio of lesions was 50.32% (7.07% to 100%). Lesion regression 100% was observed in 2 cases (4.88%). There was a negative correlation between the CNV lesion area and reduction ratio (r=-0.380, P=0.042) and the flow lesion area and reduction ratio (r=-0.402, P=0.030). CONCLUSION: Macular vessel density decreases, FAZ turns smaller and more irregular in mCNV eyes. Anti-VEGF therapy is efficient for mCNV without affecting vessel density and FAZ, but it is unable to completely eliminate CNV lesions in most cases. The bigger mCNV lesions have lower reduction ratio.