Search PubMed⌕ Search

Biomedical subjects

J C Walsh

Publications and source records attributed to J C Walsh.

At least 55 records · Page 3Linked to original sources
PubMed1986

Visual evoked responses in chronic alcoholics.

Visual evoked responses (VERs) were recorded on 52 chronic alcoholics patients without Wernicke-Korsakoff syndrome, 22 of whom had cerebellar ataxia, and eight chronic alcoholics with Wernicke-Korsakoff syndrome. Abnormal VERs were found in 23% of patients without and 37% of patients with Wernicke-Korsakoff syndrome. The main VER abnormalities of all the alcoholic groups were prolonged latency and reduced amplitude of the P100 component. Improvement followed a six month period of abstinence. VERs may be useful in the early detection of alcohol induced brain damage, and in following the progress of patients with the condition.

Adult↗
PubMed1984

Abnormalities of proximal conduction in acute idiopathic polyneuritis: comparison of short latency evoked potentials and F-waves.

Motor and sensory conduction studies, F-wave latency, and the latency of evoked potentials from the brachial plexus and cervical spine in response to median nerve stimulation were examined in 17 patients with acute idiopathic polyneuropathy. Short latency evoked potentials provided a higher yield of evidence of abnormalities of proximal conduction than did the F-wave latency. Both methods of studying conduction in the proximal segments of a peripheral nerve may be normal, however, in a small number of patients who have significant pathological lesions.

Adolescent↗
PubMed1984

Chronic polyneuropathy of undetermined cause.

The case histories of 519 patients with peripheral neuropathy on whom sural nerve biopsy had been performed were reviewed. In 67 patients (50 males, 17 females) (13%) who had symptoms of a symmetrical polyneuropathy for more than one year, the cause remained undiagnosed in spite of intensive investigation. Patients with inflammatory neuropathy were not included, but represented 17% of the whole series. The mean age of onset of symptoms was 50.6 years, and the median time from onset of symptoms to initial investigation was 2 years. Males were affected more commonly than females in a ratio of 3:1. The clinical features in 43 patients were those of a mixed motor and sensory neuropathy, in 17 patients a predominantly sensory neuropathy and in 7 patients a predominantly motor neuropathy. The mean CSF protein was 0.73 g/l and in only six patients was it greater than 1 g/l. Nerve conduction studies most commonly demonstrated mild slowing of motor conduction and impairment of sensory conduction. The usual pathological changes on sural nerve biopsy were those of chronic axonal degeneration. Forty seven patients (70%) were re-examined at intervals of time which ranged from 4 months to 12 years after their initial presentation and nerve biopsy (median, 3 years). As a group, they were only mildly disabled, the condition had a very slowly progressive course and there had been little change in their disability. A possible aetiological factor was found in 17 of the 47 patients (36%) and included malignancy, alcoholism, and benign paraproteinaemia. It is concluded that with intensive investigation the cause of chronic polyneuropathy of duration greater than one year remains undetermined in only about 13% of patients and that continued follow-up is worthwhile since a diagnosis may be established on re-examination.

Adult↗
PubMed1983

Visual evoked potentials in the detection of subclinical optic toxic effects secondary to ethambutol.

In 14 patients with tuberculosis treated with ethambutol hydrochloride, pattern-reversal visual evoked potentials (VEPs) were recorded to monocular, whole-field stimulation before the commencement of treatment and one month and three months subsequently. In six subjects, the VEPs showed changes in the latency and amplitude of the P100 component at the one- or three-month interval. In three cases, the VEP changes reversed after cessation of treatment. In five of the six cases, changes were not associated with a change in visual function, as measured by clinical neuro-ophthalmologic examination. Our findings confirm the usefulness of VEPs in the detection of subclinical optic nerve disease and suggest their use in routine monitoring of ocular function in patients treated with ethambutol.

Adolescent↗
PubMed1983

Somatosensory evoked responses in the diagnosis of thoracic outlet syndrome.

A study was made of 11 patients with cervical rib, and one patient with Klippel-Fiel syndrome and enlarged transverse processes to determine whether evoked potentials recorded from both Erb's points and the cervical spine in response to median and ulnar nerve stimulation provided information additional to that obtained by EMG and peripheral conduction studies. It was found that in seven patients who had pain and paraesthesias but no objective neurological signs both the peripheral and central conduction studies were within normal limits. By contrast, of five patients who had objective signs, conventional EMG and conduction studies were abnormal in three patients, but abnormalities of the evoked potentials obtained from ulnar nerve stimulation were obtained in all five patients. It is suggested that this application of evoked potential estimation is a useful addition to the more conventional peripheral investigations.

Adolescent↗
PubMed1983

Peripheral neuropathy associated with polycythemia vera.

Nerve conduction studies were performed on 26 patients with polycythemia vera, 11 of whom had sensory symptoms in the extremities and 3 of whom had clinical signs of peripheral neuropathy. There was significant impairment of sensory conduction in the ulnar and sural nerves and mild slowing of motor conduction in the lateral popliteal nerve. Sural nerve biopsies were performed on three patients. The pathological findings, including teased fiber studies, were consistent with mild chronic axonal degeneration. There is an association between polycythemia vera and peripheral neuropathy.

Adult↗
PubMed1982

Evoked potential changes in clinically definite multiple sclerosis: a two year follow up study.

Visual, spinal and somatosensory evoked potentials were performed on 56 patients with clinically definite multiple sclerosis at the beginning and end of a 2 1/2 year follow-up period. At the initial examination one or both visual evoked potentials were abnormal in all but nine patients (84%), five of whom had abnormalities of either spinal or somatosensory evoked responses; that is, one or more abnormal results were obtained from 52 of 56 (91%) patients. At the final examination there were abnormalities of one or more evoked potentials in 55 of the 56 (98%) patients. There was an increase in latency of the components of the evoked responses over the period; reduction in latency in individual patients was exceptional. The change in these electrophysiological measurements correlated with the increase in clinical disability of the group of patients over the period of study.

Acoustic Stimulation↗
PubMed1980

Transfer factor in treatment of multiple sclerosis.

A 2-year prospective double-blind trial of the treatment of multiple sclerosis patients with the leucocyte extract, transfer factor (TF), obtained from leucocytes of relatives living with the patient, was conducted. 60 patients with definite MS, of whom 58 completed the trial, were divided into two equal groups, one of which received TF and the other placebo. The groups were evenly balanced with respect to sex ratios, disability, duration of disease, ratio of moderate to severe cases, and HLA phenotype. Neurological, electrophysiological, and immunological assessments were done at the start of the trial and every 6 months thereafter. The results indicated that (1) TF retarded but did not reverse progression of the disease; (2) a significant difference between treatment and placebo groups was not apparent with 18 months after the start of the trial; and (3) treatment was effective only in those patients with mild to moderate disease activity.

Adolescent↗
PubMed1977

Myotonia precipitated by propranolol therapy.

A 39-year-old man with ischaemic heart-disease developed clinical myotonia while taking propranolol. The myotonia disappeared when administration of the drug ceased. The patient appears to have dystrophia myotonica which had not been evident before propranolol therapy.

Adult↗
PubMed1977

The effect of ethyl alcohol on striated muscle: some clinical and pathological observations.

Electrophysiological and pathological studies have been performed on three patients with recurrent focal swelling of the calf muscles simulating deep venous thrombosis, and in a patient with both cardiomyopathy and skeletal muscle disease. In all patients there were elevated CPK levels, histological evidence of an acute myopathy, heavy alcohol intake prior to the development of symptoms, and improvement in hospital with the cessation of alcohol consumption. These patients illustrate a form of alcoholic muscle disease which may be more common than generally realised.

Adult↗
PubMed1977

Electrophysiological and immunological studies in optic neuritis.

Serial clinical and electrophysiological examinations and immunological investigations have been performed on 34 patients with primary optic neuritis. In 8 patients, the latency of visual evoked responses was normal after the resolution of clinical symptoms, and in a further 5 patients improvement in VER latency occurred although the response remained abnormal. In 17 patients, VER's abnormal and did not alter over the period of clinical recovery; in 4 patients there was a progressive increase in the latency of the VER's through both eyes although a satisfactory clinical recovery occurred. The frequency of histocompatibility antigens was similar in the group of ON patients to that in the normal population. Immunological function was normal in patients with ON as assessed by levels of immunoglobulins. T and B lymphocyte numbers and by lymphocyte blastogenesis in response to PHA and myelin basic protein. Three patients have developed multiple sclerosis, all of whom had either HLA-A3 or -B7 antigens; the clinical and electrophysiological pattern of recovery was different in each case.

Cerebrospinal Fluid Proteins↗
PubMed1976

Acute idiopathic polyneuritis. A clinical and electrophsiological follow-up study.

Fifty patients with acute idiopathic polyneuritis have been studied clinically and electromyographically, and sural nerve biopsy was performed on 8 patients. Motor and sensory conduction studies were within the normal range in 7 patients (14%), and there was pronounced slowing of motor conduction in 25 patients (50%). There was no apparent correlation between the degree of conduction, and the clinical disability of the patient or the duration of the acute illness. Eighteen patients were re-examined at intervals up to 5 1/2 years after the onset of their illness. Eight patients (44%) were clinically normal at follow-up examination and 4 patients (22%) had a significant disability. There was no relationship between the clinical disability at follow-up examination and the results of initial or final nerve conduction studies. Electromyographic evidence of denervation, however, may indicate that complete clinical recovery will not occur. Segmental demyelination was the primary pathological change found in sural nerve biopsies and there was a significant reduction in the density of myelinated fibres in 2 nerves. It is suggested that a subacute onset of the illness,electromyographic evidence of denervation or gross slowing of conduction, and significant reduction of numbers of myelinated fibres or onion-bulb formation on sural nerve biopsy are factors which may indicate a prolonged course of the illness or incomplete recovery.

Acute Disease↗
PubMed1976

Peripheral neuropathy complicating primary hyperoxaluria.

A patient with chronic renal disease due to primary hyperoxaluria developed a rapidly progressing motor neuropathy with marked impairment of nerve conduction. Pathological studies demonstrated the presence of both axonal degeneration and segmental demyelination, together with the presence of oxalate crystals within axons. It is suggested that the development of peripheral neuropathy complicating hyperoxaluria is a consequence of the increased life-span mad possible by haemodialysis.

Adult↗
PubMed1976

Gian axonal neuropathy--a generalized disorder of cytoplasmic microfilament formation.

Light and electron microscopy of a sural nerve biopsy obtained from a patient with giant axonal neuropathy revealed the presence of numerous axonal spheroids which were composed chiefly of neurofilaments. Large discrete masses of cytoplasmic microfilaments were also observed in endoneurial fibroblasts, endothelial cells, Schwann cells, perineurial cells and cultured skin fibroblasts. Neuronal degeneration in giant axonal neuropathy appears to be part of a generalized disorder of cytoplasmic microfilament formation.

Axons↗