There have been trends to equate normal with an ideal state of health, and disease with disturbances that are determined solely by subclinical abnormalities. While in any living language there is a conflict between established definition and the need for change, modification in the use of words that are of such central importance to medical writing requires cogent justification that has not been forthcoming in these instances. To avoid further obscuration of the literature, the term normal should be limited to its traditional connotation of average, and the term disease should be reserved for disturbances of health that are clinically manifest.

As a resident of Dr. Penfield, I was impressed by his clinical analysis of each patient's complex medical problem. This always included a detailed history and physical examination by the “Neuro” staff with added information gathered by Dr. Penfield during his personal interviews with each patient. This clinical information was later reinforced by extensive operative notes and hand drawn pictures by Dr. Penfield along with photographic studies of the operative site. I soon realized how important it was to collect complete documentation on each patient.

Four patients with Multicore Myopathy, a rare morphologically distinct myopathy, are described. Although previously considered to be a non-progressive or only slowly progressive myopathy, progression to significant disability was seen in three of our cases. The association of cardiac disease with Multicore Myopathy has not been previously emphasised. All four patients in this study had a cardiomyopathy, and heart disease was the cause of death in two of the patients. Multicore Myopathy is not always a benign entity. Cardiac involvement, when present, adversely affects prognosis.

Tizanidine (Sirdalud) was compared to baclofen (Lioresal) in a randomized, double-blind, cross-over trial. Each medication was introduced over a three week titration period and then maintained at the highest tolerated dose for five weeks. The two treatment phases were separated by a one week drug withdrawal and a two week washout period. Sixty-six patients entered the trial and forty-eight completed both treatment phases. At the end of the trial, neurologists and physiotherapists thought that baclofen was superior on the basis of perceived efficacy and tolerance (p≤0.05). Although the efficacy of tizanidine or baclofen was judged as good to excellent by 24 and 39% of patients respectively, this difference was not statistically significant. Muscle weakness was the most common adverse effect. This was significantly more troublesome in patients treated with baclofen. Somnolence and xerostomia were more common in patients treated with tizanidine. Both baclofen and tizanidine appear to be useful adjuncts in the treatment of spasticity in patients with multiple sclerosis. Preference of either drug is tempered principally by side-effects.

We have examined the diagnostic significance of finding one band in the immunoglobulin (IgG) region in spinal fluid protein electrophoresis. From January 1983 to January 1986, 855 consecutive CSF electrophoreses were performed on as many patients. A blinded observer identified a single band in the IgG region in 53 cases (6.2%). In only 14 patients (26%), were the clinical features ultimately felt to be due to clinically definite or possible multiple sclerosis (MS). The majority of patients with a single band had another neurological diagnosis (55%) or were neurologically normal (6%). Many of the neurological disorders in which a single band was found were not disorders in which an increased intrathecal synthesis of immunoglobulin or electrophoretic restriction would have been expected. A variety of conditions can produce a single band pattern. The significance of these patterns and the means by which they might be identified are described.

In order to determine whether disturbances in GABA homeostasis might play a role in the pathogenesis of sepsis-related encephalopathy, serum and brain tissue GABA concentrations from six areas of the brain (cortex, diencephalon, striatum, hippocampus, midbrain, and pons-medulla) were determined in a rat model of bacterial sepsis (cecal ligation and perforation). The results were compared to those obtained from sham operated control animals. All septic animals demonstrated clinical signs of encephalopathy and had elevated serum GABA levels (0.92 ± 0.3 uM versus 0.48 ± 0.15 in controls, p < 0.01). GABA content in the specific subcompartments of the brain, however, were similar in the two groups. These results indicate that although serum GABA levels are elevated during sepsis, GABA is unlikely to play an important role in the pathogenesis of sepsis-related encephalopathy.

Evoked potentials were studied in 22 children with leukodystrophy [10 metachromatic leukodystrophy (MLD), 4 Pelizaeus-Merzbacher (PM), 3 Krabbes, 2 adrenoleukodystrophy (ALD), and one each of Alexander's, Canavan's and multiple sulphatase deficiency (MSD) diseases]. The ABRs were abnormal in all patients (except for the younger ALD), but varied with the type of leukodystrophy. The PM and Krabbes patients had abnormal ABRs with a loss of the rostral waves, accompanied in Krabbes with delayed I-III interpeak latencies; in MLD, ALD and MSD prolonged interpeak latencies were found. Three patients who had no clinical signs, but were positively diagnosed as MLD on the basis of absent arylsulphatase A, also had abnormal ABRs. The SEPs were abnormal in all patients. Cortical SEPs were absent in 16 and abnormal in 5 who were in the earlier stages of their disease. Cervical SEPs were within normal limits except for the Krabbes and MLD patients studied, who showed peripheral slowing. The VEPs were normal in only 6 and, unlike the ABRs and SEPs, did not seem to covary with clinical severity across the various leukodystrophies but did correlate with disease progression. Thus, multimodal EPs are useful in the diagnostic differentiation of the leukodystrophies.

Two Parkinsonian patients with chronic nonconfusional dopaminomimetic psychosis were treated with a course of electroconvulsive therapy. In both cases sustained remission of psychosis was obtained in the face of ongoing administration of dopaminomimetics.

We report the case of a young boy being considered for pituitary surgery because of pituitary enlargement found during assessment of growth delay. There was no goitre but he was hypothyroid clinically and biochemically. The finding of an elevated TSH suggested primary thyroid disease with thyrotroph hyperplasia. Treatment with L-thyroxine resulted in prompt resolution of his pituitary enlargement and improvement in his visual fields.

Lymphocytic adenohypophysitis (LAH) is an uncommon disorder in the spectrum of pituitary disease. Twenty-three cases proven by biopsy or at autopsy have been reported since 1962. We report 2 further cases and review the etiology, immunology and pathology of the disease. The diagnosis should be considered in afemale patient who presents during the post-partum period with the clinical picture of a non-functional or prolactin cell pituitary adenoma and evidence of hypopituitarism.

We describe a child with Brown-Sequard syndrome beginning at C8-T1, immediately following Harrington rod instrumentation for idiopathic scoliosis. We believe this is most likely related to either a common variation of the branches of the anterior spinal artery to one side or due to rupture of the ipsilateral spinal vein. This possible complication should be considered in patients undergoing Harrington rod instrumentation.

The surgical results in 40 patients with syringomyelia, treated with a syringosubarachnoid shunt or other procedures are reviewed. The principal indication for surgery was that of significant neurological deterioration. There were 12 patients with idiopathic syringomyelia without tonsillar ectopia, 12 with an associated Chiari malformation, 11 with post-traumatic syringomyelia and five patients with spinal arachnoiditis. There were 38 syringosubarachnoid shunts performed in 35 patients, and an excellent or good result was achieved in 26 patients (74.3%). In terms of the type of syringomyelia, the best results were obtained in the idiopathic group without tonsillar ectopia and in the post-traumatic group. A short duration of pre-operative symptoms favoured a better outcome, and in our opinion, early surgical treatment is indicated for all patients with neurological deterioration. All eight patients in whom a posterior fossa decompression was performed as the initial surgical procedure required a second operation, either a syringosubarachnoid or syringoperitoneal shunt to achieve neurological improvement or stabilization. Thus, the syringosubarachnoid shunt is an effective therapeutic modality for patients with syringomyelia, particularly for the idiopathic and post-traumatic groups. More than one surgical procedure may be required to achieve cessation of deterioration. Overall, excellent or good results were achieved in 29 (72.5%) of the 40 patients.

The history of the provision of artificial vision by electrocortical stimulation has its origin in observations over 50 years ago. However, the realistic modern stimulation of human visual cortex is only 20-years-old. No useful device has been devised as yet and it therefore remains purely experimental. The primary objective of such a prosthetic device is that of independent mobility. This would require the appreciation of half-tone pictures, the detection of depth and discontinuities in outlines, and a significant quality of resolution. Some of the problems which threaten resolution in such a device and the factors which must be overcome in order to achieve a useful visual prosthesis are discussed.

We have had experience with diaphragm pacing in 24 patients at the Toronto Western Hospital. Fourteen patients have undergone bilateral implants to treat chronic ventilatory insufficiency (CVI) caused by traumatic tetraplegia at the C1/2 level (eight patients), neurogenic apnea (five) and one case of neonatal apnea. Unilateral stimulators for nocturnal pacing have been implanted in five patients with central alveolar hypoventilation (sleep apnea) and five patients who suffered CVI resulting from various etiologies. Of the patients who were ventilatory dependent, 80% were successfully weaned and in the entire series, 58% of the patients are living. Diaphragm pacing was successful in 67%, partially successful in 8% and ineffective in 25%. The major complications were: death by pneumonia, failure of the radio receivers, and infection. Diaphragm pacing is the treatment of choice for patients who are ventilator dependent and tetraplegic from upper cervical trauma or in some cases of neurogenic apnea; it may be life saving for patients who suffer central alveolar hypoventilation.

The authors present their experience with intraoperative monitoring of cochlear nerve action potentials (AP) in 30 adult patients. Operative procedures were acoustic neuroma excision with attempted hearing preservation and selective vestibular neurectomy in patients with incapacitating Meniere's disease and serviceable hearing (SRT<50 db, discrimination >60%). Loss of AP is detected rapidly and has been demonstrated after manipulation of the cochlear nerve and after coagulation of small arteries on the tumour capsule. Presence of an AP at the end of the procedure usually correlates with postoperative preservation of hearing. AP monitoring appears to be a reliable means of detecting potentially reversible changes in cochlear nerve function intraoperatively.

Techniques used to monitor the function of the seventh and eighth cranial nerves during acoustic neuroma and other posterior fossa surgery are reviewed. The auditory brainstem response (ABR), electrocochleogram (ECochG) and direct recording from the auditory nerve (CNAP) were compared. The best technique is the ECochG, although in many cases, the CNAP should be used as a back-up technique. The CNAP is especially useful for the identification of the auditory nerve. Both can provide real-time feedback on the physiological integrity of the auditory nerve. The ABR may be helpful in monitoring brainstem function. For some procedures, optimal monitoring requires the combined recording of all three techniques.

Monopolar constant-voltage intracranial stimulation of the facial nerve is helpful for the identification and preservation of the facial nerve. Audio monitoring of spontaneous electromyographic activity provides real-time feedback on the effect of surgical manipulation of the nerve. Monitoring of ephaptic transmission in the facial nerve during microvascular decompression for hemifacial spasm aids in the identification of the offending vessel.

The objectives of the present study were to evaluate the relationship between the fractional amplitudes of the EEG derived from power spectral analysis (PSA) of the electroencephalogram (EEG) and depth of coma measured clinically with the Glasgow Coma Score, and to assess the accuracy of PSA in predicting long-term outcome. Thirty-two patients rendered unconscious by blunt head injury (mean (GCS = 7) had intermittent EEG recordings daily from 1-10 days post injury. There was a significant correlation between fractional amplitude of the EEG and the GCS. The rate and magnitude of change in the EEG and GCS were also correlated. There were significant differences in PSA parameters between improved and deteriorated patient groups at the termination of monitoring (p = .02) and in the change of PSA parameters over time (p = .02). Using linear discriminant analysis of PSA parameters, the accuracy of outcome prognostication based on the six month outcome was approximately 75%. Accurate classification of outcome was possible in a number of patients in whom there was little or no change in the GCS during the period of monitoring.