Comparison of retinal vessel measurements in digital vs film images.

Abstract

To compare central retinal artery equivalents (CRAE) and central retinal vein equivalents (CRVE) from vessels measured from images captured with a digital camera and digitized images taken with a film camera. Comparison of techniques. Clinic. A total of 75 eyes of 48 adults. Gradings of retinal vessel diameters from images produced by using two photographic techniques: directly from a 45 degrees digital camera and digitized by scanning from a 30 degrees film-based camera. Differences in CRAE and CRVE from two types of images. CRAE and CRVE were highly comparable between the two techniques with correlation coefficients of 0.88 and 0.87, respectively. Estimates of CRAE and CRVE from measurements taken from digitally captured and digitized film-based images were highly comparable. It is likely that inferences about factors associated with retinal vessel diameters will be unbiased by the method of imaging.