[Extradural temporopolar approach for surgical management of paraclinoid lesions]

Surgical treatment of paraclinoid tumors adjacent to important anatomical structures, such as the optic nerve, optic chiasm, pituitary stalk, and internal carotid artery, should emphasize maximum resection and preservation of visual function. Thus, early localization and exposure of the optic nerve, and complete mobilization and decompression of the optic nerve and internal carotid artery, are necessary in order to prevent intraoperative neurovascular injuries. However, this technique requires wide exposure of the optic-carotid space through the interpeduncular cistern. We have developed an extradural temporopolar approach for resection of paraclinoid tumors, which can also allow early devascularization of arteries that feed the tumors. We evaluated the surgical outcomes of this approach, paying special attention to clinical and visual outcomes.

Thirteen patients(4 men, 9 women;24-78 years, mean age 54 years), underwent tumor removal using an extradural temporopolar approach between March 2000 and April 2013. We retrospectively reviewed medical charts, radiological findings, intensive care unit flow sheets, and surgical records.

Histological diagnoses included craniopharyngioma(4 cases), pituitary adenoma(3 cases), medial sphenoid ridge meningioma(2 cases), tuberculum sellae meningioma(2 cases), trigeminal neurinoma(1 case), and malignant epidermoid(1 case). Tumors were 1.5-6.0cm in length(mean 3.2cm). Tumors were cystic in all 4 craniopharyngiomas and solid in the other 9 cases. Preoperative neurological deficits included visual disturbance in 10 patients, double vision caused by oculomotor nerve palsy in 2 patients, and vertigo in 1 patient. Additional orbitozygomatic craniotomies were performed in 8 patients. Total tumor removal was performed in 7 patients and subtotal removal performed in 6. The pituitary stalk was microscopically preserved in all patients. Postoperative complications included transient diabetes insipidus in 2 patients, chronic subdural hematoma in 1 patient, and abducens palsy in 1 patient. All complications were completely resolved. Surgical outcomes on discharge were recorded as follows:good recovery(11 patients), moderate disability(1 patient), and severe disability(1 patient, who suffered preoperative consciousness disturbance). Visual outcomes were improved in 7 patients, unchanged in 5, and worsened in 1, with recurrence.

The present extradural temporopolar approach, which allows early decompression of the optic nerve, and early devascularization and detachment of the tumor, may lead to greater tumor resection and improved visual outcomes in patients with paraclinoid tumors.