MORPHOMETRICAL ANALYSIS OF RETINAL ARTERIAL MACROANEURYSMS

Twenty-one macroaneurysms and related vessels of 19 patients were eval uated morphometrically. Macroaneurysms were classified into two groups as hemorrhagic and exudative in terms of their major clinical sign. A verage diameters of the macroaneurysms were arranged in a Gaussian dis tribution curve (mean and standard deviation: 281.60 +/- 57.28 microme ters). Regarding the distribution curve based on this data macroaneury sm can be defined as being greater than 109.76 micrometers, Macroaneur ysms were most frequent on the superotemporal vessels (52.38%), follow ed by the inferotemporal (38.10%), inferonasal (4.76%) and superonasal vessels. Average diameter (r=+0.68, p=0.0006) and area (r=+0.71, p=0. 0003) of the macroaneurysms were significantly correlated to the diame ter of the relevant arterial segments. The distribution of the macroan eurysms in respect to arterial bifurcation (chi(2)=18.762, p=0.0003) a nd arteriovenous crossings (chi(2)= 8.286, p=0.0405) were nonrandom wi th macroaneurysms clustering near this points. Hemorrhagic macroaneury sms were significantly closer to the optic disc (p<0.01) and were loca ted on relatively larger arterioles (p<0.01). They were also more circ ular (p<0.01) in shape and greater in area (p<0.01) and diameter (p<0. 01) than the exudative ones. These findings suggest that the location of the macroaneurysm is closely related to its clinical appearance.