The patient is lying in the supine position on the operating table with the head secured in the Mayfield head holder. The skin is cut slightly posterior to the frontal hair line from zygoma to zygoma. The scalp and pericranial flaps are reflected anteriorly. A burr hole is placed on each side of the orbital buttons. A craniotomy is performed extending anteriorly as close as possible to the orbital roof and posteriorly along the convexity of the cranium. The basal line of the craniotomy involves both tables of the frontal sinuses, and the mucous membranes are completely removed. The dura is cut parallel to the base and the sagittal sinus is ligated and cut at the cecal foramen; the falx is transected to open up the operative field (Fig. 16.2).

For the pterional approach, operative positioning is similar to the frontolateral approach, but the head is rotated more to the contralateral side (30–40°). The single burr hole is placed at the same location, but the craniotomy is performed more posteriorly exposing the frontal and temporal lobe with the Sylvian fissure and the sphenoid ridge. The lesser wing of the sphenoid is resected to the superior orbital fissure depending on the tumour size, to allow exposure of the lesion with minimum brain retraction (Fig. 16.3).

When the frontolateral or pterional approach is performed, the ipsilateral optic nerve and the internal carotid artery are first identified. The tumour capsule is opened medial to the ipsilateral optic nerve and the tumour debulked to decompress the optic nerve using microsurgical techniques. Tumour resection is continued in a piecemeal fashion until the optic chiasm and the contralateral optic nerve are visible. Regardless of the selected surgical approach, it is paramount to avoid injury to the blood supply of the optic apparatus. As the inferior surface of the optic nerve and chiasm receive their blood supply from a group of small arteries, which arise from the medial wall of the internal carotid artery [6], these may not be mistaken as tumour feeders and the use of bipolar coagulation should be restrictive. Special attention has to be paid for the identification and preservation of the optic cistern and also the separation of the layers of the optic cistern and the tumour capsule. To preserve the small arteries supplying the optic nerve and chiasm, it is advisable to leave the tumour capsule until the end of sufficient tumour debulking and preparation. This will provide a protective plane of dissection for the optic nerves and optic chiasm as well as the perforation vessels. Only when enough space is achieved after tumour removal, the tumour capsule should be removed respecting the arachnoidal plane to the small vessels.

Then the tumour matrix is coagulated and the basal dura resected. In case of hyperostosis or bony tumour involvement, this site is removed with a diamond drill. Tumour resection is completed to the posterior direction, when the pituitary stalk becomes visible and is preserved. In case of eventual opening of the sphenoid sinus, a pericranial flap or fascia of the temporal muscle with addition of fibrin glue has been used for covering the defect to avoid any postoperative CSF fistula.

The authors’ surgical series includes 72 meningiomas solely arising from the tuberculum sellae treated through three different surgical approaches between 1978 and 2002. Tumours were operated through the frontolateral (1984–2002, n = 30), pterional/frontotemporal (1982–2002, n = 21) and bifrontal (1978–1995, n = 21) approaches. Four patients of them experienced previous surgeries in outside hospitals.

The maximum tumour diameter ranged from 1 to 5 cm with a mean diameter of 2.8 cm. Tumours size was <3 cm in 39 cases (54.2 %) and ≥3 cm in 33 cases (45.8 %).

The mean diameter of tumours was 2.5 cm (1–5 cm) in patients operated through the frontolateral approach, 2.66 cm (1–5 cm) in cases where the pterional/frontotemporal approach was used and 3.49 cm (1.5–5 cm) in cases where the bifrontal approach was performed. In tumours involving the cavernous sinus, the intracavernous part of the tumour was not radically removed to prevent any new cranial neuropathies (Fig. 16.4a–e).