Pattern reversal visual, brain-stem auditory, and short latency median nerve somatosensory evoked potentials (EPs) were evaluated in a prospective study over 4 years in 20 patients with clinically definite sclerosis (MS). Standardized neurological examinations were done at regular intervals and correlated with EP findings. The highest incidence of EP abnormalities occurred in the visual system followed by the somatosensory and auditory systems. Clinical relapse was usually accompanied by EP deterioration, but clinical improvement often occurred without parallel EP recovery. EP changes were not always related to clinical symptoms and often took place during remission periods in the absence of clinical changes. There was no significant correlation between clinical and electrophysiological progression within any given sensory modality. The progression of clinical disability, however, showed a fairly good correlation with the overall progression of EP abnormalities. We conclude that EPs complement the neurological exam in the evaluation of MS and may have a place in the investigation of the effects of therapeutic agents on the neurological status in MS.

In a follow-up study (mean, approximately six months), nitrazepam was helpful in suppressing periodic movements in sleep (sleep-related myoclonus) and improving disturbed sleep physiology and daytime symptoms of 13 patients (mean age - 53 yr).

Our findings dispel the commonly held belief that the EEG always worsens progressively in dementia of the Alzheimer's type. In a continuing cohort analytical study of dementia, 139 patients with Alzheimer's disease and 148 controls were studied for EEG abnormalities and progression. EEGs were read without knowledge of the previous EEGs or clinical condition, and classified according to the presence of diffuse delta or theta, bisynchronousspikes, projected activity, and focal activity. EEGs were significantly different in the two groups. EEG scores generally worsened over 1-4 years, but most of the subjects showed no alteration in their EEG scores. A few patients with Alzheimer's disease showed improvement of EEG findings.

The effect of clonazepam on the restless legs syndrome was studied in a group of 6 patients. Following a drug-free period, 3 patients received clonazepam for 4 weeks followed by placebo for 4 weeks thereafter and 3 patients received the same medication and for the same length of time but in reverse order. The effectiveness of the medication was evaluated by means of a self-rating system in which patients assigned a score daily to the degree of discomfort experienced in the previous 24 hours. Three patients improved on clonazepam but 2 of these also improved on placebo. Clonazepam was not shown to be significantly more effective than placebo in the treatment of RLS.

We report a 50 year old woman with primary hypothyroidism and nemaline myopathy to call attention to the rare coexistence of these two disorders.

A sample of 122 patients with Parkinson's Disease was studied for the purpose of investigating if the frequency of relatives affected with Parkinson in this group was higher than in a control group and to see if the genetic load was more important in some of the subtypes of Parkinson described by Barbeau and Pourcher (1982).7 In our 122 patients, we found that 1.7% were post-encephalic parkinsonian, 12.3% were symptomatic cases and 86% of the idiopathic variety. There were 16.1% early onset patients in the idiopathic group and among these we found 23.5% with a positive family history of Parkinson in the first-degree relatives. In 6 cases with the tremor onset form of the disease, the family history was positive and 5 patients, 4.7% had familial essential tremor-related Parkinsonism. Our results support Barbeau's hypothesis7.19 that Parkinson is a heterogeneous disease in which some subtypes (such as early onset Parkinson) have an important genetic subceptibility component.

Three patients are described with pathologically verified Creutzfeldt-Jakob disease (CJD) who presented with localizing clinical signs accompanied by focal electroencephalographic abnormalities including periodic lateralized epileptiform discharges (PLEDS). With further progression of the disease, diffuse background slowing and continuous bisynchronous periodic discharges appeared in all three cases. There was good correlation between the initial focal clinical manifestations and the EEG findings.

Prolonged electroencephalographic and video monitoring of ictal events is useful in aiding the diagnosis of complicated seizure disorders. Forty eight patients admitted to a neurology service were assessed with this technique. Twenty five (54%) had their diagnoses changed, six (14%) had their diagnoses confirmed and the remaining patients had inconclusive studies. Therapy is modified by the results and in addition both patient and staff education is enhanced through the use of this equipment.

We describe eight cases of primary cerebral lymphoma seen in Manitoba from 1980 to 1985.

The clinical presentation is similar to other primary brain tumors. The diagnosis should be considered when single or multiple, often deep lesions, show dense enhancement on computerized tomographic (CT) scan, but are avascular at angiography. These tumors are histologically indistinguishable from non-Hodgkins lymphomas arising outside the CNS.

The prognosis is poor. However, radiotherapy with or without surgery may offer significant palliation. Although there is no consensus on the value of chemotherapy, corticosteroids alone or multiagent chemotherapy have shown promise in a few cases. For these reasons, histologic diagnosis should be sought in all cases and surgery, radiotherapy, and chemotherapy should be considered, as prolonged survival is possible.

The terms “cortical” and “subcortical” dementia are controversial; however, the clinical distinction between them is real. For example, although Alzheimer's and Parkinson's disease (prototypical of cortical and subcortical dementia, respectively) share clinical features, they differ in the presence of aphasia, apraxia, and agnosia in Alzheimer's disease but not in Parkinson's dementia. We review our studies aimed at clarifying the mechanisms underlying the differences between these neurological disorders. Experimental paradigms adopted from animal models were used to study the functional anatomy and neuropsychological characteristics of Alzheimer's and Parkinson's disease. The tasks administered include delayed alternation (DA) and delayed response (DR), which are sensitive to frontal system damage, and tactile discrimination learning (TOL) and reversal (TRL) paradigms sensitive to parietal system damage. Alzheimer's patients were significantly impaired on all tasks whereas Parkinsonians with dementia were impaired only on DR and TRL. Consideration of neuroanatomical and neuropsychological mechanisms involved in DA, DR, TOL, and TRL appears to have sharpened the distinction between Alzheimer's and Parkinson's dementia. Dementia in Alzheimer's disease may involve dorsolateral frontal, orbitofrontal and parietal systems. In contrast, dementia in Parkinson's disease may involve prominent dorsolateral frontal system damage.

Vigabatrin (ɣ-vinyl GABA; GVG), an irreversible inhibitor of GABA-transaminase, at a daily dose of 2-4 g, and a placebo were each administered orally for 4 months to 14 patients with cerebellar ataxia (9 with Friedreich's ataxia, 5 with olivopontocerebellar atrophy), in a double-blind, placebo-controlled crossover study. For the group as a whole, there was no significant difference between the GVG and placebo periods in any of the parameters of cerebellar symptomatology measured. Individually, one patient showed some improvement after 3 months of treatment with 2 g/day GVG. Tolerance to 4 g/day GVG was poor, whereas 2 g/day was well tolerated. The results suggest that agents which increase central GABA concentrations are not likely to be of benefit to patients with Friedreich's ataxia or olivopontocerebellar atrophy.

A Tourette-like syndrome (TLS) may occur after long-term neuroleptic treatment. A review of 11 cases reported in the literature is given. We describe the onset of a TLS in a 13-year old boy with childhood schizophrenia after short term, low-dose treatment with thioridazine. The syndrome resolved 5 months after neuroleptic withdrawal. Subsequent exposure to neuroleptics (mainly perphenazine) induced a recurrence of motor tics and involuntary vocalizations which resolved on drug discontinuation. Awareness that neuroleptics may induce a TLS may lead to prompt recognition and avoidance of labelling the manifestations as symptoms of the underlying psychosis or attention-seeking behaviour.

We describe the clinical characteristics and a series of magnetic resonance imaging (MRI) studies in a patient with the features of dorsal midbrain syndrome occurring in the setting of multiple sclerosis. A T2-weighted MRI study revealed a discrete abnormality in the tectum of the midbrain whereas a high volume delayed computed tomography (CT) scan was uninformative. In parallel with remission of the clinical findings, the MRI abnormality diminished over time and was no longer visible at one year suggesting that some MRI detected MS lesions can completely disappear with time. This report demonstrates the use of MRI to detect and to follow sequentially sites of known disease activity in MS.

The relationships between total and free serum valproate (VPA) concentrations and seizure control, serum liver enzyme activity and plasma ammonia concentration were studied in 61 epileptic children. Enzymeimmunoassay (EMIT)R methods gave higher values of total VPA concentration than gas-liquid chromatography (GLC) methods. In over 80% of children with complete seizure control the ranges of total VPA concentration were 140-420 umol/L with GLC methods and 210-560 umol/L with EMIT methods. The range of free VPA concentrations in 78% of children with complete seizure control was 8.8-26.4 umol/L. Increased liver enzyme activity was observed in 6 of the 61 children and raised plasma ammonia concentration in 11 of 50 children. Plasma ammonia concentration was related to total serum VPA but was not related to free serum VPA. Increased serum liver enzyme activity was related to VPA dose per kg but not to free or total serum VPA concentration. Thus free VPA concentrations do not appear to be more useful than total VPA concentrations in predicting seizure control and do not correlate with liver enzyme activity or plasma ammonia concentration.

Language impairment in Alzheimer's disease has become an important clinical issue. It has been recognized for some time that the disease may begin with aphasia and even before frank aphasia develops, some of the earliest changes in a large number of individuals consist of impairment of word fluency and semantic access manifesting itself in word finding difficulty. The second major issue concerning language in Alzheimer's disease is that the cases which have early severe language impairment may represent a more progressive familial variety of disease as it has been suggested in the literature. This is still subject to controversy. Finally, it will be documented that the later stage of the disease shows language invariably impaired and goes through stages of dissolution that resemble anomic, transcortical sensory, Wernicke's and global aphasias. Accurate assessment of language may turn out to be one of the most reliable predictors of the stages of Alzheimer's disease and provides important insights into the cerebral organization of language, semantic access, relationship of semantic and episodic memory and the pathophysiology of the disease.

The optic neuritis of systemic lupus erythematosus (S.L.E.) more frequently results in the persistence of a central scotoma or complete blindness after a single attack than demyelinating optic neuritis, although the initial clinical presentations may be identical. A significant number of patients, however, recover normal vision. Optic neuritis may be the presenting symptom of S.L.E. and as myelopathy may also occur in the course of the disease, confusion with multiple sclerosis may result, especially if there are no arthritic, cutaneous nor visceral manifestations. We report a case of lupus optic neuritis associated with anticardiolipin antibodies and a circulating lupus anticoagulant and suggest these may be a marker for vasculitic optic neuritis and play a role in its aetiology.

We report an autopsy study of a 64-year-old female with systemic sarcoidosis. In addition many muscles showed typical light and electron microscopic features of inclusion body myositis. To our knowledge this association has not been previously reported.

We report the clinical and pathological findings of the unusual combination of two idiopathic central nervous system diseases, multiple sclerosis and amyotrophic lateral sclerosis in a 56 year old physician with a twenty-seven year history of a disease initially characterized by relapses and remissions, followed by an eight year quiescent period. During the last year of life there was rapid deterioration with development of generalized weakness, atrophy, weight loss and fasciculations of body and tongue, and associated difficulty with swallowing and sudden respiratory failure. The autopsy confirmed characteristic “burned out” plaques of multiple sclerosis and anterior horn cell and axonal degeneration of amyotrophic lateral sclerosis.

The electroencephalograms of 40 children with permanent cortical visual impairment (CVI) were studied. CVI was diagnosed in the presence of severe visual loss, normal or minimal ocular findings and clinical, electrodiagnostic and CT evidence of postgeniculate lesions involving the visual cortex. All patients had a multidisciplinary evaluation, including extensive neurological and ophthalmological investigations. The records did not contain any specific features which would be diagnostic of CVI. Isolated occipital spikes were rare and more commonly multifocal EEG disturbance was seen because of diffuse cerebral involvement. Photic stimulation was of little use in the diagnosis. Multihandicapped children with profound CVI tended to show multifocal abnormalities, no alpha rhythm and a suppressed posterior waking background in their EEGs, whereas those with more residual vision usually had an alpha rhythm. The presence or absence of alpha rhythm seemed to reflect the intactness of the striate cortex. However, the lack of alpha rhythm was not always associated with total blindness and not all children with useful residual vision had alpha rhythm.

Currently the diagnosis of progressive organic dementia is one of exclusion offered only after cognitive decline is well advanced. Early in the disease process, memory complaints most often bring elderly people to the attention of their family physician .This behaviour represents the first step in the process of giving a patient the medical diagnosis of organic dementia, yet no systematic method has been developed to gather such subjective information and evaluate its medical significance. We are developing a memory complaints questionnaire and a brief non-threatening memory screening instrument to help identify organic dementia in its earliest stages. The screening device will be related to more sophisticated neuropsychological measures of dementia and it should be sensitive to mental deterioration over short periods of time. The instruments will document perceived and objective changes in memory and will help the physician attribute their findings to normal aging, depression and/or degenerative CNS disease.