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

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

Method: 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.

Result: 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.

Conclusion: 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.