Abstract
Purpose :
To perform a fully automated quantitative assessment of retinal and choroidal microvasculature in eyes with diabetic maculopathy (DM) using optical coherence tomography angiography (OCT-A) and to identify potential compensatory mechanisms secondary to focal vascular impairment.
Methods :
Retrospective case series of 48 eyes of 48 patients with DM (19 females, mean age 66.2 ± 9.4 years) and 47 eyes of 47 age-matched controls evaluated by Spectralis HRA-OCT2 (Heidelberg Engineering, Heidelberg, Germany). The Full-spectrum probabilistic-decorrelation angiography (FS-PDA) generated optical coherence tomography angiograms of the superficial (SCP) and deep (DCP) capillary plexuses and of the choriocapillaris (CC) layer. A fully automated micro-structural analysis, obtained by a custom built software (AngiOCTool+™) provided data on FAZ metrics and SCP, DCP or CC vessel density. A comparative analysis between different vascular layers was performed; the obtained data were also compared with those of healthy subjects.
Results :
A statistically significant difference (p<0.05) in FAZ surface values was shown between the SCP and DCP both in diabetic and healthy subjects, while no differences were reported for vascular densities. A negative linear correlation in terms of vessel density was reported between CC and both SCP and DCP in diabetic patients (Spearman’s coefficient of rank correlation); at the reverse a positive linear correlation between the same parameters was noticed in healthy subjects. Capillary density values were significantly lower (p<0.05) in all retinal vascular layers and choriocapillaris of DM patients compared with healthy subjects.
Conclusions :
A fully automated quantitative OCT-A approach is a useful imaging system for detecting diabetic-induced focal vascular impairment both in retinal and choroidal layers. Retinal and choroidal vascular networks, although distinct entities, seem functionally interconnected: varying the degree of perfusion may be a mutual compensatory mechanism in response to an ischemic injury.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.