Instruments for endoscopic endonasal transsphenoidal surgery.

TECHNIQUE: Endoscopic transsphenoidal surgery. New, developing, minimally invasive technique. Removal of pituitary lesions and tumors of the parasellar region. TECHNICAL DEVELOPMENT: Endoscopic endonasal transsphenoidal surgery. Endonasal, not transnasal, procedure. Great respect of anatomy. Very wide surgical field, without intraoperative use of a nasal speculum, but with less room in which to work (only one nostril) and potential conflict between the surgeon's hands and the endoscope (both when entering the nostril and while working inside). INSTRUMENTATION: New instrument. Secure grip. Barycenter of the instrument is the surgeon's hands. Many different tips with different functions. Elimination of the bayonet-like shape. Handle bent in the horizontal plane to avoid interference with the surgeon's hands and to allow the distal, thin part of the instrument to be used safely and comfortably.

Peduncular hallucinations associated with large posterior fossa meningiomas.

Peduncular hallucinosis may be observed in patients with thalamic or brain stem ischemia or hemorrhage, while it has been less often described in association with brain stem or cerebellar tumors. We report in this paper two cases associated with large posterior fossa meningiomas. In the first patient hallucinosis appeared preoperatively as a result of brain stem compression and ceased after the tumor removal. In the second patient hallucinosis occurred after the surgery, as a result of surgical trauma with local brain stem edema, and ceased 4 days after treatment with desamethasone and carbamazepine.

Connections of sympathetic fibres inside the cavernous sinus: a microanatomical study.

A microanatomical study has been designed to investigate the pattern of arrangement of the sympathetic fibres inside the cavernous sinus. The course of these fibres has been examined in 60 fresh specimens of parasellar region from autopsy cadavers. Apart from the thin branches arising at different intervals along its course, the sympathetic plexus of the carotid artery gives rise to a large division that usually joins the abducens nerve and leaves it to combine with the ophthalmic branch of the fifth. In 10% of specimens we have found a direct connection between sympathetic fibres and the ophthalmic branch of the trigeminal nerve. We did not recognise similar connections with oculomotor and trochlear nerves.

Objective pulsatile tinnitus: case report.

Anomalies in the vascular structures of the neck, cranial base, temporal bone, and intracranial circulation may give rise to pulsatile tinnitus. If the anomalous sound is perceived also by others, then it is defined as objective tinnitus. Herein, the case is reported of right pulsatile tinnitus of one year's duration, which appeared after cranial trauma. Magnetic resonance angiography showed that the jugular bulb was dominant on the same side as the tinnitus. The tinnitus was recorded with a high-sensitivity microphone, while otoacoustic emissions were measured by distortion products during follow-up.

Cervical spine stenosis due to ossification of the posterior longitudinal ligament in Italian patients: surgical treatment and outcome.

Ossification of the posterior longitudinal ligament (OPLL) of the cervical spine is a frequent pathological entity in people of Japanese and Asian extraction and is reported with increasing frequency also in the USA; on the contrary, reports in the European and particularly in the Italian literature remain rare. This paper describes 8 Italian patients with cervical spine stenosis due to OPLL extending three to five vertebral segments (and above C3 in four cases). Magnetic resonance imaging shows the extent of the ossification well in terms of height and cord compression, while computed tomography is useful to measure the thickness of the bone mass and the residual spinal canal. Anterior cervical decompression by discectomy, corpectomy, and removal of the ossified ligament is the treatment of choice and results in clinical improvement in most cases. Decompressive laminectomy may be reserved for patients with ossification extending to four or five levels and above C3. The surgical technique and intraoperative findings are discussed.

Two cases of quadriparesis following anterior cervical discectomy, with normal perioperative somatosensory evoked potentials.

Two cases illustrate an uncommon failure of perioperative somatosensory evoked potential (SEP) monitoring to detect iatrogenic lesions causing temporary quadriparesis during straightforward cervical surgery. In both cases, anterior cervical discectomy at one or two levels was undertaken with bone graft and titanium implants, and cortical SEP were monitored to alternate stimulation of the left and right median or ulnar nerves. The SEP showed only minor changes during surgery, not considered pathologically significant, and were normal when recorded postoperatively. Both patients, however, experienced marked postoperative limb weakness or paralysis. Motor evoked potentials (MEP) recorded postoperatively to transcranial magnetic stimulation were absent. The clinical motor deficits resolved over the ensuing months. In spite of the normally low incidence of "false negatives," in these two cases SEP monitoring failed to detect a iatrogenic lesion causing moderate to severe, though temporary, motor impairment. Monitoring of MEP may be considered as an alternative to SEP during anterior cervical procedures, while combined monitoring of SEP and MEP may be the ideal.

Endoscopic surgery for pineal region tumors.

Endoscopic surgery may play an important role in most patients with pineal region tumors. We report our experience with 5 patients treated by a burr hole endoscopic technique. The procedure included in all cases third ventriculostomy for the correction of hydrocephalus, CSF sample for cytology and tumor markers, and tumor biopsy for histological diagnosis. Endoscopic biopsies showed a pineocytoma in two cases, a germinoma in 2 and a low-grade astrocytoma in one. We agree that endoscopic surgery may allow us to select cases requiring a microsurgical approach (medium-sized or large non-germ-cell tumors) from cases to be treated only by irradiation and chemotherapy (germinomas and other non-germ-cell tumors). Then, in some patients with pineal region tumors the endoscopic procedure remains the only surgical treatment. When a direct microsurgical approach is indicated, it may be performed in a non-emergency situation and after correction of the hydrocephalus by endoscopic third ventriculostomy.