Electrophysiological characterization of pre- and postoperative facial nerve function in patients with acoustic neuroma using electrical and magnetic stimulation techniques.

Facial nerve function was examined in patients who underwent posterior fossa surgery for unilateral acoustic neuroma. Examinations took place prior to surgery (n = 47 patients), early after surgery (0-12 days, n = 16 of 47 patients), and late after surgery (187-1505 days, n = 29 of 47 patients). Clinical signs of facial palsy were present to a variable extent in 13 of 47 patients before, in 12 of 16 patients early, and in 18 of 29 patients later after surgery. Electrophysiologically, the facial nerve was stimulated electrically at the stylomastoid fossa and magnetically at its proximal intracanalicular segment. In addition, the face-associated motor cortex was stimulated magnetically. In patients with facial palsy, any of these stimulation methods resulted in a decreased amplitude of the response in the nasalis muscle. The decrease showed a linear relationship to the clinical grade of palsy, pre- and postoperatively. Corticomuscular latencies remained unchanged. We conclude that: (i) the electrophysiological characteristics of facial nerve lesions due to compression by acoustic neuromas or due to a complication of neuroma removal are those of a purely axonal neuropathy; (ii) the three stimulation techniques have a similar diagnostic yield, thus making the use of all three of them redundant; and (iii) the electrophysiological techniques allowed no prediction of the final facial nerve function.

Treatment of neurocysticercosis.

The clinical and laboratory data of 88 black patients with computed tomographic (CT) evidence of active neurocysticercosis were analysed. The CT appearance of neurocysticercosis was distinctive in the majority. Seizures, chronic headache and neuropsychiatric changes were the most common clinical presentations. Hydrocephalus was diagnosed in 17 patients (9 obstructive and 8 communicating) and cerebral infarction with focal neurological deficit occurred in 4 cases. All patients were treated with praziquantel (Biltricide: Bayer Miles). There was complete cyst clearance after two courses in 14 patients and in 16 cases the mean percentage reduction in cyst number was 85.88% and in cyst size 80.84%. In 1 patient there was no response to treatment. Although praziquantel was effective in parenchymal neurocysticercosis, it was ineffectual in the treatment of 5 patients with cysticercal meningitis. There were 2 deaths in the series.