PROPORTIONAL ANALYSIS OF THE KIDNEY ARTERIAL SEGMENTS

The proportional area of each renal arterial segment was analyzed in 4 9 polyester resin corrosion endocasts of the renal vasculature. We def ined a segmental artery as a primary or secondary branch of the renal artery that could be isolated outside the hilum. We found kidneys with five arterial segments in 30 of 49 casts (61.2% of cases) and kidneys with four arterial segments in 19 of 49 casts (38.8%). To enable the evaluation of the proportional areas of the autonomous segments (by us ing the ''point-counting planimetry method''), each arterial segmental branch was injected with different-colored resin. The superior segmen t (apical) was present in 36 of 49 casts (73.5% of cases) and had a me dian proportional area of 13.02%. The anterosuperior and anteroinferio r segments were present in 30 of 40 casts (61.2% of cases) and had med ian proportional areas of 21.36% and 17.18%, respectively. The anterio r segment was present in 19 of 49 casts (38.8% of cases; when the mid- kidney anterior surface received only one segmental artery) and had a median proportional area of 28.44%. The inferior segment was present i n 100% of cases and had a median proportional area of 22.65%. The post erior segment was also present in 100% of cases and was the segment wi th the greatest median proportional area (33.76%).