Preservation of Venous Drainage in Middle Fossa During Combined Transpetrosal Approach for Petroclival Meningioma.

Abstract

The combined transpetrosal approach enables wide exposure around the petroclival region by lifting of the middle fossa dura and cutting of the tentorium. However, interruption of the venous drainage on the middle skull base during the transpetrosal approach has been reported to lead to temporal lobe damage.^1,2Video 1 demonstrates a microsurgical technique for the preservation of various venous drainage in the middle fossa including the sphenobasal and sphenopetrosal veins during the combined transpetrosal approach for treatment of a petroclival meningioma. The patient is a 51-year-old woman with a petroclival meningioma extending into the cavernous sinus. The superficial middle cerebral vein drained into the foramen ovale as the sphenobasal vein, and the sphenopetrosal vein draining into the superior petrosal sinus coursed on the middle skull base. A developed middle meningeal vein was also identified on the middle skull base. While preserving the venous drainage in the middle fossa by a modified incision of the middle fossa dura, sufficient decompression of the brainstem was achieved by removal of the cisternal part of the tumor. The patient developed diplopia after the surgery, but her headache and dizziness were improved without other neurologic deficits. The patient's diplopia improved within 1 year after the surgery, without any other neurologic deficits or tumor regrowth during the follow-up period of 3 years. Informed consent was obtained from the patient.