Classification and automated detection of retinal arteriovenous crossing morphology in systemic arterial hypertension using infrared scanning laser ophthalmoscopy

Abstract

Purpose : To investigate whether retinal vascular analysis of arteriovenous (AV) crossings in Infrared Scanning Laser Ophthalmoscope (IR-SLO) images using convolutional neural networks (CNN) may contribute to classification and risk stratification of patients with systemic hypertension.

Methods : Medical records and IR-SLO images were reviewed for 152 consecutive patients. Healthy control group images were used to assess normal vasculature. The morphologic characteristics of AV crossings were compared between patients with and without hypertension, evaluating continuity of the central venous light reflex and the presence of venous narrowing. Retinal specialists manually categorized all images by the severity of change; a subset of 99 images was analyzed using a CNN model.

Results : Sixty-three patients (51%) had systemic hypertension. Venous changes at AV crossings were more common in hypertensive patients (44/63, 70%) compared to normotensive patients (19/61, 32%; P < 0.0001). Moderate changes were seen in 25 (40%) hypertensive patients compared to 15 (25%) normotensive patients (P=0.002). Severe changes were noted in 19 (30%) hypertensive patients compared to 4 (7%) normotensive patients (P=0.001). Output predictions of the CNN model had a mean Average Precision (mAP) of 81% for image classification.

Conclusions : The presence of morphological changes at AV crossings is correlated with hypertension in this series of patients. The authors propose that IR imaging may be used in the clinical setting to evaluate hypertensive retinal vasculature changes and provide a framework for automated classification and risk stratification.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.

 

Classification of AV crossings based on retinal vasculature morphology

 

Infrared Scanning Laser Ophthalmoscope classification of retinal vasculature changes at arteriovenous (AV) crossings. In (A)-(C) the arrows point to normal AV crossings with no change in venous reflectivity or diameter. Note the regular central bright stripe with dark borders on the underlying vein. In (D)-(F) the arrows point to moderate vascular changes with altered reflectivity of the underlying venous lumen lacking a defined dark border. No changes in venous diameter are present. In (G)-(H) the arrows point to severe vascular changes with diminished reflectivity of the underlying vein, no dark border, and significant decrease in venous diameter.