Abstract
Purpose :
Reliability of OCTA measurements can be affected by various factors including ocular media opacity, imaging artifacts, and patient cooperation during image acquisition. The potential for variation in OCTA measurements may limit its widespread clinical adoption. Studies validating (or refuting) the repeatability of OCTA measurements are essential. In this cross-sectional study, we report the intrasession repeatability and interocular symmetry of macular OCTA parameters in patients with Alzheimer disease (AD), mild cognitive impairment (MCI), and Parkinson disease (PD).
Methods :
OCTA images (3x3mm and 6x6mm) centered on the macula were acquired using the Zeiss Cirrus HD-5000 AngioPlex. Perfusion density (PFD), vessel density (VD), and foveal avascular zone (FAZ) area repeatability were assessed using intraclass correlation (ICC) analysis. Interocular symmetry of PFD, VD, and FAZ area were also assessed.
Results :
Sixty-one eyes of 36 AD patients, 81 eyes of 52 MCI participants, 55 eyes of 32 PD participants, and 57 eyes of 31 normal cognition participants who underwent 3x3mm OCTA imaging were analyzed. 59 eyes of 35 AD patients, 86 eyes of 53 MCI participants, 63 eyes of 36 PD participants, and 55 eyes of 31 participants with normal cognition who underwent 6x6mm OCTA imaging were analyzed. For 3x3mm OCTA images, ICC values for PFD circle were as follows: AD (0.68; 0.50-0.78 CI), MCI (0.68; 0.53-0.77 CI), PD (0.63; 0.41-0.75 CI), and normal cognition (0.38; 0.22-0.64 CI). For 6x6mm OCTA images, ICC values for PFD circle were as follows: AD (0.64; 0.44-0.76 CI), MCI (0.74; 0.64-0.83 CI), PD (0.57; 0.35-0.70 CI), and normal cognition (0.60; 0.37-0.73 CI). Similar ICC values were observed for VD and FAZ area, although values trended slightly higher for FAZ area. Apart from inner ring PFD on 6x6mm OCTA images in normal cognition participants (0.40; 0.15-0.60 CI) and MCI (0.74; 0.62-0.82 CI), there were no significant differences in repeatability among or between groups. Interocular differences in OCTA parameters were only observed in AD patients who underwent 6x6mm OCTA imaging.
Conclusions :
Overall, similar macular OCTA repeatability was observed between normal cognition participants and those with neurodegenerative disease. Regardless of diagnostic group, macular OCTA metrics demonstrated moderate repeatability. On average, FAZ area was more repeatable than VD or PFD.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.