Surgical Approach to Ponto-mesencephalic Cavernoma.

BACKGROUND AND AIMS: The surgical treatment of intrinsic brainstem lesions remains a major challenge. In this article we present the results of using an infratentorial-supracerebellar (ITSC) approach for the resection of intrinsic ponto-mesencephalic lesions. MATERIALS AND METHODS: The authors reviewed the cases of 16 patients. In seven of them, a paramedian ITSC transcollicular approach was used to resect intrinsic mid-brain lesions, and in the other nine patients, an intermediate or lateral ITSC infra-trochlear approach was used for ponto-mesencephalic lesions. RESULTS: All 16 lesions were completely removed. There was no recurrence of bleeding during the follow-up period, and no mortality. In seven patients with mid-brain lesions, the preoperative ocular symptoms improved in three of them, and the neurological deficits - other than ocular symptoms improved - in five of them. The preoperative modified Rankin Scale score of 1.8 improved to 1.3 postoperatively. In nine patients with a ponto-mesencephalic lesion, the preoperative ocular symptoms improved in four of nine patients, and the neurological deficits other than ocular symptoms improved in five of them, while one patient exhibited venous infarction in a cerebellar hemisphere that caused neurological deterioration. The preoperative modified Rankin Scale score of 3.75 improved to 2.5 postoperatively in these patients. CONCLUSION: The ITSC transcollicular or infra-trochlear approach provide a wide operative entry zone and minimize the functional damage to the surrounding structures for access to ponto-mesencephalic lesions.