[Clinical application of the combined presigmoid supra-infratentorial approach]

To explore the surgical approach to the lesions of the cerebellopontine angle and the petroclival region.

Nine cases of the cerebellopontine angle or petroclival large tumors and one case of the posterior cerebral thrombotic aneurysm were treated by the combined presigmoid supra-infratentorial approach. The tumors including 3 cases of schwannomas and 6 cases of meningiomas spaned supra-infratentorium in our study.

Complete tumor removal were achieved in 6 cases, and subtotal tumor removal in 4 cases. After the operation, Cerebrospinal fluid leakage followed intracranial infection occurred in 1 case which losing follow-up. Headache and dizziness relieved in the other 9 cases. One case improved and 3 cases with no improvement after surgery among the 4 preoperative facial paralysis patients. Three cases with cerebellar symptoms were much relieved, but most deficits involving other cranial nerves preoperation did not recover. According to Samii's prognosis standard, 7 cases with good results and 1 case with common and 1 case with bad had been achieved. The hearing level had no influence in 5 cases, declined 20 dB HL in 2 cases, 30 dB HL in 1 case and 60 dB HL, in I case.

The combined presigmoid supra-infratentorial approach is a direct route to the petroclival region and the cerebellopontine angle, provides a wide surgical field with less cerebellar or brain retraction, facilitates the removal of lesions and preserves the cranial nerves functions.