RESUMO
Background Choroidal neovascularization (CNV) is a major cause of visual loss in many fundus diseases.Fundus angiography (FA) is essential for the diagnosis,location and treatment of CNV.However, FA is an invasive examination method.Split spectrum amplitude decorrelation angiography (SSADA) OCT can quickly and clearly provide vascular signals.However, whether SSADA-OCT is feasible in the evaluation of CNV remains unclear.Objective This study was to detect and quantify CNV using OCT angiography.Methods Thirteen patients with unilateral CNV were included in Beijing Tongren Eye Center from June 2014 to August 2014.All affected eyes of the subjects were scanned with a high-speed frequency domain OCT.The SSADA-OCT images were obtained by scanning of macula covered 6 mm×6 mm area.The CNV area and grey scale were computed from the en face OCT images of retinal layer and choroidal layer.This study followed the Helsinki Declaration and was approved by the Ethics Committee of Beijing Tongren Hospital,and written informed consent was obtain from each patient prior to any medical examination.Results SSADA-OCT angiogram revealed CNV area and location confirmed by fluorescein angiography,and the CNV blood flow information of internal limiting membrane,inner plexiform layer,retinal pigment epithelium,and choroid was exhibited by OCT angiography.All CNVs with different causes showed the well defined and hyperreflected signal in macular region.The average CNV area was (0.15 ±0.09)mm2 , and the average grey scale of CNV was 75.40±32.35 in the affected eyes,and that in the contralateral eyes was 26.99±22.87 in the 300 μm area,showing significant elevation in gray scale in the affected eyes compared with the contralateral eyes (t =6.946, P＜0.001).Conclusions OCT angiography is a noninvasive observation technique of retinal and choroidal blood flow.It can provide quantitative information and detailed images of CNV.