THE RETE-MIRABILE OF THE CLIVUS AND THE DORSUM SELLAE - A MICROANATOMICAL STUDY

The osteofibrous space underneath the dura mater of the dorsoclival ar ea was studied with respect to the arterial branches arising from the internal carotid cartery at this level. Special attention was given to the main variations of branching and anastomosing patterns Found in t his area. Our results indicate that the meningohypophyseal trunk is th e main supplier of the dorsoclival area. The dorsal meningeal artery w as present in all cases. In the course of this vessel three main varia tions were observed. The inferior hypophyseal and the tentorial artery also contributed to the arterial supply of this region, A large numbe r of anastomoses between the internal and external carotid artery was present as well, Because of the refinement of microsurgical and interv entional techniques pathological lesions like tumors and vascular malf ormations of the dorsoclival area are frequently accessable. The knowl edge of the microvascular anatomy of the clivus and tile dorsum sellae is important as the rich collateral network found in this area may co ntribute to the arterial supply of pathological lesions arising here.