Normal Retinal Vascular Pattern: Arteriovenous Pairing and A/V ratio

ABSTRACT

All physicans regard the fundus as an important guide to prognosis in the systemic disease which permits the retinal changes, especially hypertension. There are fallacies in the ophthalmoscopic examination of as essing arteriolar calibre by the arteriovenous ratio. The selection of comparable vessels by ophthalmoscopy for the estimation of the arteriovenous ratioshould be fully appreciated, and no other reference base is available unless measurments are made on retinal photographs or by means of an ophthalmoscope fitted with a special graticule. Studies were made by a random selection of 30 normal persons (60 fundi) in 2nd decades. This series of fundus color photographs incorporated a field extending to 3-5 disc diameters from the disc margin. This paper is a series on the retinal vessels which was concerned with the arteriovenous comparable pairing and its ratio. The results were 1. Total comparable pairs ware 142 pairs in the 60 fundi. 2. In the 60 fundi comparable pairs were found in 50, and in 118 out of 240 quadrants(48 percent). 3. Comparable pairs were found more frequently in the temporal half of fundi. 4. The mean A/V ratio was 0.703.