Measurement of progression of Gyrate Atrophy using Ultra-Wide Field fundus photography

Abstract

Purpose: To measure the progression of atrophic lesions in two patients with gyrate atrophy and establish a novel method of follow-up for this hereditary dystrophy.

Methods: A retrospective, longitudinal, observational and comparative study of two patients with gyrate atrophy. Ultra-wide field fundus photographs was performed in two consecutive visits one year apart. Solitary lesions were observed to be present in both visits, excluding atrophy that became confluent with other lesions over time. The atrophic zones were measured using the area measurement caliper software ten times to get an average due to high variability of measurements. The optic nerve was measured also to determine changes in size due to patient position in both photographs. New solitary lesions in the follow-up photograph were also measured.

Results: Thirty-two corresponding individual lesions were observed and measured. Mean growth of lesions (difference between size measured at follow-up with size at baseline) was 4418.24 pixels2, with a standard deviation of 225.0 pixels2. Pixel area of new individual lesions presented a mean of 1586.08 pixels2, with a standard deviation of 957.36 pixels2.

Conclusions: Ultra-wide field photographs can be an objective method to measure progression of atrophic lesions in patients with gyrate atrophy. High variability of individual measurements require performing repeated measurements to homogenize data.

Keywords: 696 retinal degenerations: hereditary • 550 imaging/image analysis: clinical • 688 retina