Surgical Approaches to the Cavernous Sinus

It has been generally accepted that the direct approach to the cavernous sinus under normal temperatures is very difficult and that the radical removal of tumors which have invaded the cavernous sinus cavity is usually impossible. The partial removal of tumors which have grown into the sinus in the form of a small nodule may cause major venous bleeding which is thought to be very difficult to control. The purpose of this paper is to describe surgical techniques for radical operation on the cavernous sinus under normal body temperatures. Thirteen cases of tumors which had invaded the cavernous sinus and 6 cases of vascular cavernous sinus lesions were operated on in the semi-sitting position which decreased venous pressure in the sinus. Biobond-soaked Oxycel was inserted into the opened cavernous sinus to control bleeding. There are four possible approaches to the cavernous sinus; the position and extent of the tumor determine which is optimal. When the tumor involves the external wall of the cavernous sinus, the tumor is removed with the external wall of the sinus. The second is the lateral approach to the cavernous sinus through the opening of Parkinson's triangle. The third is the subfronto-pterional approach with removal of the planum sphenoidale, the tuberculum sellae, and the anterior wall of the sella turcica to expose the entire optic nerve in the optic canal. Through this approach, the anterior inferior cavity and the medial cavity of the cavernous sinus could be opened in order to expose the C-3 and C-4 segments of the internal carotid artery. The last approach is the posterior approach to the cavernous sinus through the transpetrosal approach combined with the subtemporal approach, which is suitable for exposure of C-5 and the posterior part of C-4 of the internal carotid artery. Out of these 19 cases, one patient with an ophthalmic aneurysm complicated by a malignant glioma died 6 months after surgery, and another one with a pituitary adenoma which invaded the cavernous sinus died of meningitis 20 days after the operation. A case of meningioma of the petroclival portion extending into the cavernous sinus developed right hemiparesis and aphasia due to postoperative intracerebral hemorrhage. One case with subtotal removal of a medial sphenoid wing meningioma which had invaded the sinus did not regain his visual acuity postoperatively. The remaining 15 cases returned to normal social activity, although one of petroclival meningiomas developed third through sixth nerve palsy and a teratoma case showed third and fifth nerve palsy.