First Author: A.Tasiopoulou UK
Co Author(s): D. Grewal B. Pal
Back to previous
To compare the quantitative differences in assessment of the choroidal neovascular membranes (CNV) of various aetiologies using two spectral domain optical coherence tomography angiography (OCT-A) Platforms.
Moorfields Eye Hospital, London, UK
12 eyes of 12 eyes with CNV (Age Related Macular Denegeration, n=5; Myopic CNV, n=2; Macular Telangectasia, n=2; Punctate Inner Choroidopathy, n=2; and Polypoidal Choroidal Vasculopathy, n=1) were scanned simultaneously using Angiovue (Optovue RTVue XR 100 Avanti (Optovue Inc., Fremont, CA, USA)) and Zeiss AngioPlex Ciruss 5000 HD-OCT (AngioPlex, CIRRUS HD-OCT 5000; Carl Zeiss Meditec, Inc, Dublin, CA). 3mm x 3mm slabs at the level of the choriocapillaris were generated using the device-software of both devices. Manual segmentation was used to confirm the anatomical boundaries. Only images free of segmentation errors and anatomical artifacts were included. Images were then exported to ImageJ (NIH, Bethesda, MD). After setting the appropriate scale, the area (mm2) and the greatest linear diameter (GLD, mm) of the CNV were measured on both platforms. Two independent retinal experts graded all images and intergrader reliability was evaluated.
Mean age was 61.8 ± 18.5 years, and there were 8 females and 4 males. Intergrader agreement between the two observers was good for assessment of CNV area (kappa =0.81) and GLD (kappa =0.78). Mean CNV area was 1.376 ± 0.52 (range 0.62-1.81) mm2 using the Zeiss Angioplex and 1.547 ± 0.087 (range 0.63 to 1.608) mm2 using the Optovue (p=0.81). Mean GLD of the CNV complex was 0.016 ± 0.010 (range 0.005-0.033) mm using the Zeiss Angioplex and 0.015 ± 0.009 (range 0.002-0.032) mm using the Optovue (p=0.98). Inter-device intraclass correlation coefficients were 0.925 (95% confidence interval; 0.562 – 0.987) for CNV area 0.78 (95% Confidence Interval; 0.098 -0.956) for CNV GLD. There was a significant agreement between measurements of CNV area using the two platforms (r=0.78, p=0.04) as well as CNV GLD (r=0.69, p=0.05).
There are minor differences in area and GLD of CNV of different aetiologies using the two different OCT-Angiography platforms. While these differences were not statistically significant in this limited series, care should be taken when assessing patients using different platforms and following their response to treatment as the CNV measurements may not be interchangeable.