Anatomic basis for conservative surgery of the spleen

100 pancreatico-splenic blocks obtained at autopsy were treated by the injection-corrosion method. The splenic artery ended in the lienorenal ligament in 64% of cases, in the pancreatic segment in 32% and in the hilar segment in 4%. In 84% of cases, the artery divided into two lobar arteries, upper and lower. In 16% the artery trifurcated. The pedicle was 20 to 60 mm long (mean 35 mm). The branches of the splenic artery were in three successive stages: the primary or lobar arteries were each associated with a lobe; the secondary or segmental arteries each supplied one of the constituent segments of a lobe; the tertiary or subsegmental arteries supplied the various areas which made up a splenic segment. Nine cases of extraparenchymal anastomoses were found. There were 32 intraparenchymal anastomoses, being either interlobar or intersegmental. There were a few interlobar anastomoses. The findings support the notion of upper and lower intersegmental and interlobar planes. The latter is almost avascular, while the former has limited vascularity. These planes make conservative surgery of the spleen possible.