Ten cases of meningioma of the pineal region were histologically verified at a single institution during an 8-year period. These represented 0.3% of 3061 intracranial meningiomas, as well as 6.2% of 164 pineal tumors. Patients were predominantly women. Symptoms and signs of increased intracranial pressure were most common, whereas Parinaud's syndrome was observed in only one case. Computerized tomography (CT) was the main diagnostic test used in the present series. It usually revealed a hyperdense mass with high-intensity contrast enhancement and a calcified mass eccentrically located at the periphery, which returned to its central location postsurgically and was likely to represent a calcified pineal gland. Magnetic resonance imaging was performed in the more recent cases and confirmed the suspicion raised by CT of a meningioma with a calcified mass at its periphery. Surgery was performed using an occipital transtentorial microsurgical approach with the patient placed in the semisitting position. Gross-total tumor removal was achieved in all cases, although this required sacrifice of the vein of Galen in six patients. Venous occlusion was performed only after adequate intraoperative verification of functional occlusion and blood flow diversion from the galenic system and had no consequences in any case but one. This latter patient had an infiltrative meningioma that was removed at the expense of intraoperative sacrifice of the two internal cerebral veins, as well as unavoidable trauma to the region of the quadrigeminal plate. All the remaining patients improved postsurgery, and only one had a permanent visual field deficit as a result of the surgical approach. Pineal meningiomas represent a rare subgroup of pineal tumors that can be treated surgically with reasonably good results. Sacrifice of major basal veins may be required to achieve radical tumor removal and can be tolerated by the patient provided that functional occlusion of the galenic system, as indicated by preoperative angiography, is verified during surgery.

Neurinomas arising from the trigeminal nerve are rare (0.1-0.4% of intracranial tumours: 1-8% of all intracranial neurinomas). A series of 111 trigeminal neurinomas operated on at the Institute of Neurosurgery "N. N. Burdenko" of Moscow, Russia, during the period 1961-1994 is presented. Clinical features, diagnostic radiology, surgery and results of treatment are discussed. We distinguished four groups of trigeminal neurinomas: a) Posterior fossa tumours; b) Tumours of the Gasserian ganglion; c) "Dumb-bell" supra-subtentorial tumours; d) Neurinomas of the peripheral branches. The complex clinical symptomatology is related to the actual location of the lesion. Surgery of trigeminal neurinomas may be very difficult, particularly in cases of dump-bell supra-subtentorial lesions. In this series, 3 cases died postoperatively. Out of the 108 patients surviving surgery, long-term follow-up (min. 13 months, max. 33 years, average 13.5 years) was available in 98 cases. 84 patients (86.7%) showed good-to excellent results, with partial trigeminal deficit as the only surgical sequela. 13 patients (11.7%) had a symptomatic recurrence following incomplete tumour removal. Second surgery, ranging from 1.4 to 9 years (average 3.8 years) following the first operation, was judged radical in 9 cases (69.2), however, the rate of complications of repeated surgery was higher than that occurring after the first operation. The advent of microsurgery, together with the introduction of the techniques of skull base surgery and of modern diagnostic imaging tools, have improved surgical results in terms of increased radicality and reduced complications.

Surgical results can be excellent if a removal, as extensive as possible, is performed using either the supracerebellar or occipital-transtentorial approach.

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The temporal branch of the facial nerve may be saved in a pterional-transzygomatic craniotomy if the dissection is carried beneath the superficial temporal fascia. The anatomical and technical aspects of this exposure are described in this report.