Laterocavernous sinus

Here we describe an anatomic structure that takes the form of a venous chan nel (VC) within the two layers of the lateral wall of the cavernous sinus ( CS). Colored gelatin was injected in both superficial middle cerebral veins (SMCV) of 29 human specimens. When a SMCV terminated into the CS, the latt er was dissected giving particular attention to its lateral wall. The termi nation of the VC and its eventual communications with the CS and adjacent v enous structures were studied. A VC in the lateral wall of the CS was found in 14 of 58 lateral walls (24.1%). It was in continuation with the SMCV in 13 cases, with the uncal vein in one case. The VC drained into the superio r petrosal sinus (71.4%), the pterygoid plexus (21.4%), or the posterior pa rt of the CS (7.2%). Two alternate drainage pathways for the SMCV were obse rved, toward the anterosuperior aspect of the CS (13.8%) or through a parac avernous sinus located along the floor of the middle cranial fossa (32.8%). These different pathways were not observed to occur concomittantly. SMCV w ere absent in 29.3%. Despite its close topographic relation with the CS, th e VC in the lateral wall can be considered as an anatomic entity with poten tial clinical relevance. We propose to call it the laterocavernous sinus. A nat Rec 254:7-12, 1999. (C) 1999 Wiley-Liss, Inc.