[Meningioma of the apex of the tentorial incisura. Diagnostic and surgical aspects apropos of a series of 7 cases].

Seven cases of meningiomas implanted on the medial portion of the free edge of the tentorium are reported. The denomination "meningiomas of the apex of the tentorial incisura" is proposed. In 4 patients, the clinical presentation was that of an intracranial hypertension without signs of compression of the quadrigeminal plate involvement. In the other 3 patients, the initial symptoms were those of the triad of the adult chronic hydrocephalus (N.P.H.) syndrome. Angiographic evaluation provides useful informations on the arterial supply (which is mainly from the tentorial branches of the internal carotid arteries and occasionally from the middle meningeal arteries) and the relationships of the tumor with the deep venous system. C.T. and M.R.I. facilitate earlier diagnosis and better demonstration of implantation and extension of the tumor, which the selection of a surgical approach is based upon. Four patients have undergone an occipital supratentorial approach and 2 a supra-cerebellar infra-tentorial approach. The meningioma was totally removed in 5 patients, sub-totally in 1 to avoid bilateral lesions of the visual pathways and cortical areas. The 7th patient was treated by C.S.F. shunt alone. No operative mortality occurred. The follow-up is averaging 18 months: 4 patients are symptom-free, 3 exhibit minor sequelae (epilepsy: 1, visual field defects: 2, memory impairement: 2). Six patients of the series have resumed their previous activities. Discussion is focused on the difficulties of surgical removal of this particular type of tentorial meningioma, resulting from volume, implantation and relationships of the tumor with the deep veins.(ABSTRACT TRUNCATED AT 250 WORDS)