The authors report on the long-term results of chronic stereotactic stimulation of the ventralis intermedius thalamic nucleus performed in 14 cases of disabling and intractable tremor. There were 10 patients with parkinsonian tremor and four with essential tremor. Three of the 10 parkinsonian patients had previously undergone contralateral thalamotomy. Tremor was assessed by clinical evaluation, surface electromyography, accelerometer, and videotape recordings before and after stimulation. The deep-brain electrode was implanted in the ventralis intermedius nucleus according to stereotactic procedure and connected to a subcutaneous pulse generator after a stimulation test period. Tremor suppression or reduction was obtained in all cases with high-frequency (130 Hz) stimulation. Marked functional improvement was maintained in 11 patients with a mean follow-up interval of 17 months. Levodopa-induced dyskinesias observed in five parkinsonian patients prior to surgery were improved or suppressed in four cases by thalamic stimulation. Stimulation was continued during the day and stopped at night in eight cases. Six patients were stimulated night and day to avoid a rebound effect which appeared as soon as the pulse generator was stopped. The only side effects were hand tonic posture in one case and persistent paresthesia in another case. The mechanism of action of this attractive treatment may be a functional alteration of the thalamic discharging area. The authors conclude that this technique is a good alternative to thalamotomy, especially when the risks of high-frequency coagulation are severe in frail and older patients.

We report on our recent experience with epidermoid cysts in the cerebellopontine angle. We operated on nine patients since 1985, seven of which were investigated with magnetic resonance imaging. Since the arrival of modern neuroimaging, large lesions can be found with only discrete symptoms, such as isolated tinnitus or unspecific headache. With computed tomography and magnetic resonance imaging, preoperative diagnosis was achieved for most patients; sometimes, however, epidermoid cysts may be very similar to arachnoid cysts. Surgery is the only possible treatment. The decision to operate should be carefully discussed for each patient, particularly if the patient is asymptomatic. The extent of the lesion at the anterior aspect of the brain stem, and sometimes above the tentorium cerebelli, fragile cortex, and vessels, and hazards of postoperative chemical meningitis often make such surgery difficult. The surgeon should not attempt total removal of the cyst membrane. Most patients who undergo surgery, however, recover well, with no or few sequelae. With a mean 3-year follow-up, no recurrence occurred, despite partial removal, as a result of the peculiarly slow growth of these lesions.

The authors report a series of 144 children with traumatic extradural hematomas operated on at the Lille Department of Neurosurgery between 1969 and 1982. The patients are divided into different groups according to age, and clinical findings were recorded for each age group. The overall mortality rate was 9%. The authors demonstrate that prognosis is related to age, neurological status at time of surgery, and duration of postoperative coma.

Surgical resection of spheno-orbital "en plaque" meningiomas should be as complete as possible to prevent tumor recurrence and therefore requires a bone reconstruction. We report a series of 20 patients operated on for spheno-orbital "en plaque" meningioma between 1981 and 1993. The surgical treatment included a resection of the involved dura and a wide resection of tumoral bone using a fronto-temporal craniotomy extended to the orbitozygomaticomalar bone ridge. The craniofacial reconstruction was performed in the same operative procedure using iliac bone autograft in 11 patients, internal cortical bone from the bone flap in 8 patients, and a coral graft in 1 patient. The cosmetic result was scored according to the following criteria: superior frontal paralysis, appearance of the orbitomalar bone ridge, shape of the external temporal fossa, and projection of the eyeballs. The cosmetic result was scored as excellent or good in 17 patients, average in 2 patients, and poor in 1 patient. The iliac bone autograft appeared to be the best material for craniofacial reconstruction because it could be modeled easily to the desired shape. However, the reconstruction technique was modified as necessary according to the extent of tumor removal, clinical presentation, and age of the patient.