Abstract
Purpose :
To compare AMD-CNV microstructures in untreated and treated eyes based on OCTA with disease duration.
Methods :
A total of 85 eyes of 85 consecutive patients with untreated or treated neovascular AMD (nAMD) (20 treatment naïve eyes, 65 eyes with previous anti-VEGF treatment) were examined using the AngioVue OCTA system (Optovue, Fremont, CA) and evaluated based on CNV morphology by two independent graders.
CNV was classified according to the following patterns: dense net (DN); vascular loop (VL); mixed (DN+VL). Further, CNV lesions were subcategorized based on vessel characteristics: branches with tiny capillaries; branches with single rare large vessels; anastomosis/loops; peripheral arcade. Based on nAMD onset, patients were grouped into 4 cohorts: Group A (no history of previous nAMD); Group B (diagnosis within last 2 years); Group C (2-4 years); Group D (4-9 years).
Results :
In 10 (50%) treatment naïve and 40 (61%) previously treated eyes, CNV lesions were identified on OCTA. Groups A, B, C and D consisted of 20, 25, 25 and 15 eyes, respectively. The mean number of injections in groups B, C and D was 4.8±3.44, 14.6±8.83 and 23.8±7.5 (mean ± SD), respectively.
Regarding main CNV types, DN could be observed in 21.1% of eyes in group A; 16% (C); 13.3% (D) and 8.3% (B); VL was most frequently present in group D (60%), followed by C (48%), A (21.1%) and B (12.5%). Mixed patterns were found in 16.7% of eyes in group B; 12% in C; 10.5% in A and 6.7% in D. The largest number of eyes with absent CNV lesions on OCTA was found in group B (62.5%), followed by A (47.4%), D (33.3%) and C (24%).
Grading of subcategories revealed that group A contained the most tiny capillary branches (31.6%), while the majority of branches with single rare large vessels was found in groups C (66.7%) and D (60%). Anastomosis/loops were most often observed in groups D (53%) and C (48%). In 21.1% of eyes in group A, 13.3% in D and 8% in C peripheral arcades were identified, while none were observed in eyes of group B.
Conclusions :
In eyes with newly diagnosed nAMD, OCTA revealed specific microstructural CNV characteristics such as DN and branches with tiny capillaries. With disease duration and injection frequency vascular loop patterns and the presence of anastomosis/loops within the CNV lesion increased.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.