End-to-end anastomosis of the posterior inferior cerebellar artery before excision of a meningioma involving the lower clivus and the foramen magnum - Case report

BACKGROUND Petroclival and foramen magnum meningiomas sometimes encase the vertebrobas ilar arterial system. Magnetic resonance imaging can clearly reveal such en casement. The case presented here was of a meningioma involving the lower c livus and the foramen magnum, encasing a lateral segment of the posterior i nferior cerebellar artery (PICA), despite the fact that no definitive diagn osis of the encasement of the PICA was made on preoperative radiological ex amination. End-to-end anastomosis of the PICA was necessary before excision of the tumor. METHODS A 55 year-old woman presented with complaints of headache and numbness of t he right upper extremity. Gadolinium diethylene-thiamine-pentaacetic acid e nhanced T1-weighted magnetic resonance (MR) images showed a homogeneously e nhanced mass lesion involving the lower clivus and the foramen magnum. Dire ct surgery was then performed, and the lateral medullary segment of the lef t PICA was found to be encased by the tumor. End-to-end anastomosis was per formed using No. 10-0 interrupted monofilament nylon sutures. Total removal of the tumor was performed after completion of the anastomosis. The patien t was free of neurological abnormalities and no recurrence of tumor was fou nd during a 2-year follow-up period. CONCLUSIONS Revascularization is sometimes thought to be required for resection of cran iospinal meningiomas even when they do not appear to encase the vertebro-ba silar arterial system on preoperative MR imaging and cerebral angiograms. I n the present case,:dissection of the PICA from the tumor was attempted, bu t was difficult due to tight encasement of the PICA by the tumor. (C) 1999 by Elsevier Science Inc.