Search PubMed⌕ Search

Biomedical subjects

M Swash

Publications and source records attributed to M Swash.

At least 217 records · Page 12Linked to original sources
PubMed1985

Unifying concept of pelvic floor disorders and incontinence.

Denervation of pelvic floor sphincter muscles is a feature of pelvic floor disorders. When severe, it may be accompanied by stress incontinence of faeces, or of urine. The extent of chronic partial denervation of these pelvic floor muscles can be quantified by electromyography (EMG), and its cause identified by electrophysiological studies of the motor innervation of these striated muscles. Damage to this innervation is often initiated by childbirth, but appears to progress during a period of many years so that the functional disorder usually presents in middle life. Incontinence develops in some patients, but not in others. This can be predicted by the severity of the abnormalities found in EMG studies of the pelvic sphincter musculature and motor latency studies of its innervation. The results of such investigations in the six common types of pelvic floor disorder are presented. Recognition of the causative factors leading to damage to the innervation of the pelvic sphincter muscles implies new approaches to treatment and to prevention of pelvic floor disorders and incontinence.

Adult↗
PubMed1985

Investigation of disorders of the anorectum and colon.

Previously, investigation of disorders of the anorectum and colon have been limited to manometric, external anal sphincter muscle electromyographic and contrast radiological techniques. In this paper we describe other investigative techniques recently developed at St. Mark's Hospital, London and their application in the investigation of certain disorders of the anorectum and colon.

Anal Canal↗
PubMed1984

Injury to innervation of pelvic floor sphincter musculature in childbirth.

71 women delivered at St Bartholomew's Hospital, London, were studied by electrophysiological tests of the innervation of the external anal sphincter muscle and by manometry. The investigations were done 2-3 days after delivery and again, in 70% of these women, 2 months later. Faecal and urinary incontinence developing after vaginal delivery has been thought to be due to direct sphincter division, or muscle stretching, but the results of the study suggest that in most cases this incontinence results from damage to the innervation of the pelvic floor muscles.

Adolescent↗
PubMed1984

Slowed conduction in the pudendal nerves in idiopathic (neurogenic) faecal incontinence.

We have studied 30 patients with idiopathic (neurogenic) faecal incontinence using anorectal manometry and concentric needle and single fibre electromyographic methods. We have measured the terminal motor latency in the pudendal nerves of these patients using a new digitally directed transrectal stimulation and recording technique (right mean (+/- s.d.) 3.2 +/- 0.9 ms, left mean (+/- s.d.) 3.0 +/- 0.9 ms) and compared the results with those obtained from 28 normal subjects (right mean (+/- s.d.) 2.0 +/- 0.5 ms, left mean (+/- s.d.) 1.9 +/- 0.3 ms). These differences between normal and incontinent patients were significant (P = 0.01) using the Wilcoxon Rank Sum Test. The findings support the hypothesis that idiopathic (neurogenic) faecal incontinence is due to damage to the nerve supply of the pelvic floor musculature.

Action Potentials↗
PubMed1984

Faecal incontinence after anal dilatation.

We have studied 10 patients with faecal incontinence occurring after anal dilatation. Abnormalities were found in the external and sphincter in clinical and manometric tests in five patients and in single fibre EMG tests in four patients. Internal anal sphincter function was impaired in eight patients. These findings have implications for prevention of faecal incontinence after this procedure.

Adult↗
PubMed1984

Electrophysiologic and manometric assessment of failed postanal repair for anorectal incontinence.

The reason for failure to improve fecal incontinence after postanal repair in idiopathic (neurogenic) anorectal incontinence is unknown. The authors have studied 20 patients whose anorectal continence was not improved after Parks' postanal repair. Anorectal manometry, single fiber EMG of the external anal sphincter muscle, and measurements of the pudendal nerve terminal motor latency were studied before and nine months after postanal repair. All 20 patients had evidence of reinnervation within the external anal sphincter muscle before operation; 17 had a raised pudendal nerve terminal motor latency and all 20 had low resting voluntary contraction anal canal pressures. No significant differences were found between the resting, voluntary contraction anal canal pressures and single fiber EMG fiber density values before or after postanal repair. However, a significant increase in the pudendal nerve terminal motor latency was found after postanal repair (P less than 0.001) using a student's paired t test. These results suggest that, in patients who are not rendered continent by postanal repair, a continuing neuropathic process takes place.

Adult↗
PubMed1984

Abnormalities of the innervation of the urethral striated sphincter musculature in incontinence.

Perineal nerve and transcutaneous spinal cord stimulation have been used to study 17 patients with idiopathic neurogenic faecal incontinence, 12 of whom also had urinary incontinence. Significant increases in spinal, perineal and pudendal nerve motor latencies were demonstrated in all 17 patients. These results suggest that there is damage to the nerves innervating both the urethral and perianal sphincter musculature in these patients, including those with isolated faecal incontinence. There was evidence of both a distal (perineal nerve) and a proximal (sacral root) component to the damage to the nerve supply of the urethral striated sphincter muscle in half of the patients.

Adult↗
PubMed1984

Perineal nerve and transcutaneous spinal stimulation: new methods for investigation of the urethral striated sphincter musculature.

The distal motor latencies in the perineal and pudendal nerves were measured in 20 normal subjects using digitally directed pudendal nerve stimulation. The mean pudendal and perineal nerve latencies were 1.9 ms +/- 0.2 (SD) and 2.4 ms +/- 0.2 (SD) respectively. In a further eight normal subjects transcutaneous spinal stimulation was used to record the motor latency from L1 and L4 stimulation sites to the urethral striated sphincter musculature. The mean spinal nerve terminal latencies from L1 and L4 were 4.9 ms +/- 0.3 (SD) and 4.1 ms +/- 0.2 (SD) respectively. These techniques can be applied to the investigation of the nerve supply to the urethral striated musculature in stress urinary incontinence and other disorders affecting the innervation of the anterior pelvic floor musculature.

Adult↗
PubMed1984

Evidence of pudendal neuropathy in patients with perineal descent and chronic straining at stool.

In 17 women with chronic constipation, and abnormal perineal descent on straining at stool, there was more severe neurogenic damage to the external anal sphincter muscle and to its pudendal innervation in those patients with a long history than in those with a short history. These results suggest that recurrent trauma to the pudendal nerves can occur during perineal descent, and that this can lead to denervation and weakness of the external anal sphincter muscle.

Adult↗
PubMed1984

Damage to the innervation of the voluntary anal and periurethral sphincter musculature in incontinence: an electrophysiological study.

In 40 women with idiopathic (neurogenic) faecal incontinence, 20 of whom also had stress urinary incontinence, single fibre EMG studies showed an increased fibre density in the external anal sphincter muscle. All these patients showed excessive descent of the pelvic floor on straining. The mean terminal motor latencies in the pudendal and perineal nerves, measured by a digitally-directed intrarectal stimulating technique, were increased when compared with 20 control subjects (p less than 0.01). The perineal nerve terminal motor latency was more markedly increased in the 20 patients with double incontinence than in those with faecal incontinence alone (p less than 0.01). These results provide direct electrophysiological evidence of damage to the innervation of the pelvic floor musculature in idiopathic faecal and double incontinence, and imply that idiopathic stress urinary incontinence may have a similar cause.

Adult↗
PubMed1984

Cancer-associated myasthenic (Eaton-Lambert) syndrome: distribution of abnormality and effect of treatment.

Treatment with plasma exchange, steroids, immunosuppressant drugs and cytotoxic chemotherapy was effective in two cases of cancer-associated Eaton-Lambert myasthenic syndrome. The clinical improvement noted during treatment was accompanied by improvement in the electrophysiological abnormality; this was much more marked in abductor digiti minimi and trapezius than in extensor digitorum brevis.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1984

Normal proximal and delayed distal conduction in the pudendal nerves of patients with idiopathic (neurogenic) faecal incontinence.

The latency of the response in the external anal sphincter muscle following transcutaneous stimulation of the cauda equina at the L1 vertebral level was measured in nine women with neurogenic faecal incontinence (mean 7.3 SD 0.7 ms) and 11 normal subjects (mean 5.6 SD 0.6 ms) (p = 0.01). There was no difference in conduction velocity between the L1 and L4 vertebral levels thus supporting the suggestion that conduction delay in faecal incontinence occurs distally.

Adult↗
PubMed1984

Management of acute viral encephalitis.

Effective therapeutic intervention in the natural history of a disorder implies understanding of pathogenesis, accuracy of diagnosis, and the availability of an effective treatment. In viral encephalitis, these are all problematic and, as a result, there is no general agreement on the preferred management strategy.

Acute Disease↗
PubMed1984

Tuberculosis of the central nervous system.

We report on the clinical features, management, and outcome of 27 patients with tuberculous disease of the central nervous system admitted to the London Hospital over six years. Seventeen presented with meningitis, and in nine of these there was bacteriological confirmation of tuberculous disease although acid fast bacilli were only found in the CSF of four patients. This appeared to carry a poor prognosis. There was a high incidence of rifampicin-induced hepatitis. The outcome was satisfactory in six out of seven patients in whom no AFBs were cultured. Eleven patients presented with intracranial tuberculomas but without evidence of systemic TB. The CT scan revealed mass lesions, but only in three patients was the appearance pathognomonic of tuberculoma. However, biopsy can be a hazardous procedure and led to the death of two of our patients. Where possible, surgical intervention should be avoided, and the response to medical treatment assessed by CT scan.

Adolescent↗
PubMed1983

A dedicated microcomputer-based instrument for interval analysis of multicomponent wave forms in single fibre EMG.

We have developed a self-contained microprocessor-based instrument compatible with conventional EMG equipment for the analysis of multicomponent SFEMG wave forms suitable for single operator use. Intervals between 4 components of a MUAP can be analysed using 3 types of threshold or window triggers. The amplitude, duration and polarity of each of these triggers can be varied independently. The instrument is portable and useful in the clinical setting.

Computers↗
PubMed1983

The overlapping innervation of the two sides of the external anal sphincter by the pudendal nerves.

Unilateral pudendal neurectomy in the monkey results in histological changes consistent with partial denervation on both sides of the external anal sphincter muscle, but much more marked ipsilaterally than contralaterally. Histological features consistent with reinnervation developed during the 9-13 weeks after unilateral neurectomy in the anterior parts of the muscle on both sides. These observations suggest that there is a substantial overlap in the pudendal innervation of the external anal sphincter muscles on the 2 sides. This derives from interdigitation of muscle fascicles across the midline in this circular muscle. This functionally overlapping innervation enables reinnervation to be partially accomplished from the contralateral side. This is important in understanding the results of electrophysiological and histopathological studies of this muscle in patients with idiopathic faecal incontinence, itself a neurogenic disorder.

Anal Canal↗