Clinical values of OCT angiography in imaging of chroidal neovascularization in pathological myopic maculopathy

Background

Myopic maculopathy leads to visual function damage.Conventional methods for the identification of choroidal neovascularization (CNV) of myopic maculopathy are fundus fluorescine angiography (FFA) and spectral-domain OCT (SD-OCT), but FFA is an invasive process and SD-OCT is incapable to image CNV well.OCT angiography (OCTA), a novel and non-invasive vascular technique, appears to be dominant in enface imaging of CNV, however, its clinical value remains to be evaluated.

Objective

This study was to evaluate the application of OCTA in imaging CNV of myopic maculopathy.

Methods

A prospective serial cases-observational study was performed.Forty-two eyes of 40 patients of myopic maculopathy were included in Ophthalmic Center, Renmin Hospital of Wuhan University from January to October 2015, with the diopter (-10.5±3.74)D.Comperehensive optical and imaginal examinations were carried out in all the eyes, including fundus photography, FFA, SD-OCT and OCTA.Ranibizumab (0.5 mg/0.05 ml) was intravitreally injected in 35 eyes of 35 patients under the informed consent and SD-OCT and OCTA were examined 1 day, 1 week and subsequent each month after injection.FFA was examined 1 month after injection.The patients were followed-up for 1-6 months to evaluate the clinical values of OCTA in monitoring the CNV of myopic maculopathy.This study followed the Helsinki Declaration and was approved by the Ethics Committee of Renmin Hospital of Wuhan University.Written informed consent was obtained from each patient prior to any medical examination.

Results

All the affected eyes showed dye leakage in CNV lesions by FFA and high reflection signal of abnormal choroidal vascular network throughout retinal pigment epithelium by SD-OCT.Clusters of high signal CNV image was clearly visible in the lesions by OCTA, and these signals were able to be displayed on both choriocapillary layer and outer layer of retina more clearly than FFA in 31 eyes of 31 patients.In 35 eyes of 35 patients received intravitreal injection of ranibizumab, CNV images on both choriocapillary layer and outer layer of retina from OCTA shrinked 1 week after injection and the lesions were stable 1 month after injection.

Conclusions

OCTA can display CNV of myopic maculopathy on the retinal outer layer and choriocapillary layer more clearly than FFA.Significant changes in the CNV net can be observed by OCTA 1 week after intravitreal injection of ranibizumab.OCTA plays an important role during the following-up of CNV therapy.

Tomography, optical coherence; Myopia, degenerative/complication; Macula; Fundus fluorescein angiography; Choroidal neovascularization/diagnosis; Prospective study; OCT angiography