Biomedical subjects

G L Morren

Publications and source records attributed to G L Morren.

10 recordsLinked to original sources

PubMed2005

Effect of sacral neuromodulation on the rectum.

BACKGROUND: Sacral neuromodulation (SNM) is a new treatment for faecal incontinence. At present the exact underlying mechanism is still unclear. Modulation of the sacral reflex arcs might have an effect on rectal sensitivity, wall tension and compliance. METHODS: Fifteen consecutive patients with faecal incontinence who qualified for SNM underwent barostat measurements before and during neuromodulation. An 'infinitely' compliant plastic bag with a volume of 600 ml was placed in the rectum and connected to a computer-controlled barostat system. An isobaric phasic distension protocol was used. Patients were asked to report rectal filling sensations: first sensation (FS), earliest urge to defaecate (EUD) and an irresistible, painful urge to defaecate (maximum tolerated volume; MTV). Rectal wall tension and compliance were calculated. RESULTS: During isobaric phasic distension each patient experienced all rectal filling sensations at the time of stimulation. Median volume thresholds decreased significantly during stimulation, from 98.1 to 44.2 ml for FS (P = 0.003), from 132.3 to 82.8 ml for EUD (P = 0.001) and from 205.8 to 162.8 ml for MTV (P = 0.002). Pressure thresholds tended to be lower for all filling sensations, but only that to evoke MTV was reduced significantly by stimulation (37.3 versus 30.3 mmHg; P = 0.005). Median rectal wall tension for all filling sensations decreased significantly with stimulation. There was no significant difference between compliance before and during stimulation. CONCLUSION: SNM affects rectal sensory perception, but further research is required to clarify the mechanism.

Adult↗

PubMed2004

Clinical measurement of pelvic floor movement: evaluation of a new device.

PURPOSE: A new device that measures pelvic floor movement clinically was evaluated. METHODS: The device consists of a rectal balloon with a magnet at its exterior end. The magnet moves in an electromagnetic field synchronous with the pelvic floor movements. This movement is measured and displayed on a computer screen in front of the seated patient. Twenty-eight healthy volunteers (15 females) were examined. On a separate day, 17 of them were tested a second time by the same investigator and a third time by a different investigator. RESULTS: One volunteer developed a vasovagal reaction. The median (range) pelvic floor lift and descent was 2 (range, 0.6-4.5) cm and 1.8 (range, 0.5-5.6) cm respectively. Day-to-day and interobserver reproducibility was good. Coughing and blowing a party balloon caused pelvic floor descent in the majority of participants. Twenty of 28 volunteers were able to expel the rectal balloon. CONCLUSIONS: The device measures cranial and caudal movements of the pelvic floor with minimal discomfort and good reproducibility. The device may have a large potential as biofeedback device in pelvic floor training.

Adult↗

PubMed2001

Latency of compound muscle action potentials of the anal sphincter after magnetic sacral stimulation.

The aim of this study was to present the failure rate and normal values for motor latency of the anal sphincter after magnetic sacral stimulation (LMSS) using a modified recording technique. A bipolar sponge electrode was placed in the anal canal for recording. A ground electrode was placed in the rectum to reduce stimulus artifact. Magnetic stimulation was induced through a twin coil energized by a Maglite-r25 generator. Two groups were examined: 14 healthy volunteers and 14 patients with a spinal cord injury (SCI) above the conus. Nine of 56 studies (16%) failed. There were no significant differences in latency between right- and left-sided stimulation or between the healthy group and the SCI patients. As described, LMSS measurements are minimally invasive and have a low failure rate. They may be used to test the integrity of the distal motor pathway in patients with bladder or bowel dysfunction who may benefit from continuous electrical sacral root stimulation.

Action Potentials↗

PubMed2001

Evaluation of the sacroanal motor pathway by magnetic and electric stimulation in patients with fecal incontinence.

PURPOSE: The aim of this controlled study was to examine whether it was feasible to use magnetic stimulation as a new diagnostic tool to evaluate the motor function of the sacral roots and the pudendal nerves in patients with fecal incontinence. PATIENTS AND METHODS: Nineteen consecutive patients (17 females) with a median age of 67 (range, 36-78) years referred for fecal incontinence and 14 healthy volunteers (six females) with a median age of 42 (range, 23-69) years were examined. Latency times of the motor response of the external anal sphincter were measured after electric transrectal stimulation of the pudendal nerve and magnetic stimulation of the sacral roots. RESULTS: The success rates of pudendal nerve terminal motor latency and sacral root terminal motor latency measurements were 100 and 85 percent, respectively, in the control group and 94 and 81 percent, respectively, in the fecal incontinence group. Median left pudendal nerve terminal motor latency was 1.88 (range, 1.4-2.9) milliseconds in the control group and 2.3 (range, 1.8-4) milliseconds in the fecal incontinence group (P < 0.006). Median right pudendal nerve terminal motor latency was 1.7 (range, 1.3-3.4) milliseconds in the control group and 2.5 (range, 1.7-6) milliseconds in the fecal incontinence group (P < 0.003). Median left sacral root terminal motor latency was 3.3 (range, 2.1-6) milliseconds in the control group and 3.7 (range, 2.8-4.8) milliseconds in the fecal incontinence group (P < 0.03). Median right sacral root terminal motor latency was 3 (range, 2.6-5.8) milliseconds in the control group and 3.9 (range, 2.5-7.2) milliseconds in the fecal incontinence group (P = 0.15). CONCLUSIONS: Combined pudendal nerve terminal motor latency and sacral root terminal motor latency measurements may allow us to study both proximal and distal pudendal nerve motor function in patients with fecal incontinence. Values of sacral root terminal motor latency have to be interpreted cautiously because of the uncertainty about the exact site of magnetic stimulation and the limited magnetic field strength.

Adult↗

PubMed2001

Effects of magnetic sacral root stimulation on anorectal pressure and volume.

PURPOSE: Electrical sacral root stimulation induces defecation in spinal cord injury patients and is currently under examination as a new therapy for fecal incontinence. In contrast to electrical stimulation, magnetic stimulation is noninvasive. To gain more insight into the mechanism of action of sacral root stimulation, we studied the effects of magnetic sacral root stimulation on anorectal pressure and volume in both fecal incontinence and spinal cord injury patients. METHODS: Three groups were examined: 14 healthy volunteers, 18 fecal incontinence patients, and 14 spinal cord injury patients. Repetitive magnetic sacral root stimulation was performed bilaterally using bursts of five seconds at 5 Hz. Anal and rectal pressure changes and rectal volume changes were measured. RESULTS: An increase in anal pressure was seen in 100 percent of the control subjects, in 86 percent of the spinal cord injury patients, and in 73 percent of the fecal incontinence patients (P = 0.03). The overall median pressure rise after right-sided and left-sided stimulation was 12 (interquartile range, 8-18.5) and 13 (interquartile range, 6-18) mmHg at the mid anal level. A decrease in rectal volume was provoked in 72 percent of the control subjects, in 79 percent of the spinal cord injury patients, and in 50 percent of the fecal incontinence patients. Overall median volume changes after right-sided and left-sided stimulation were 10 (range, 5-22) and 9 (range, 5-21) percent from baseline volume. An increase in rectal pressure could be measured in 56 percent of the control subjects, 77 percent of the fecal incontinence patients, and 43 percent of the spinal cord injury patients. Median pressure rises after right-sided and left-sided stimulation were 5 (range, 3-12) and 5 (range, 3-5) mmHg. CONCLUSIONS: Magnetic sacral root stimulation produces an increase in anal and rectal pressure and a decrease in rectal volume in healthy subjects and patients with fecal incontinence or a spinal cord injury.

Adult↗

PubMed2001

Anatomy of the anal canal and perianal structures as defined by phased-array magnetic resonance imaging.

BACKGROUND: The anatomy of the anal canal and perianal structures has been imaged using endoluminal magnetic resonance imaging (MRI). Phased-array MRI avoids the use of an endoluminal coil that may distort anatomy. The aim of this study was to describe the anatomy of the anal canal and perianal structures using phased-array MRI. METHODS: Imaging was performed in 14 men and 19 nulliparous women. The dimensions of the anal canal, puborectalis, external anal sphincter, perineal body, superficial transverse perineal muscle, bulbospongiosus, ischiocavernosus and anococcygeal body were measured in different planes, and sex differences were calculated. RESULTS: The lateral canal was significantly longer than its anterior and posterior part (P < 0.001). The anterior external anal sphincter was shorter in women than in men (P = 0.01) and occupied, respectively, 30 and 38 per cent of the anal canal length (P = 0.001). The caudal ends of the external anal sphincter formed a double layer. The perineal body was thicker in women than in men (P < 0.001) and easier to define. The superficial transverse muscles had a lateral and caudal extension to the ischiopubic bones. The bulbospongiosus was thicker in men than in women (P < 0.001). The ischiocavernosus and anococcygeal body had the same dimensions in both sexes. CONCLUSION: Phased-array MRI is a non-invasive technique that allows an accurate description of the normal anatomy of the anal canal and perianal structures.

Adult↗

PubMed2001

Audit of anal-sphincter repair.

OBJECTIVE: Structural damage of the anterior part of the anal sphincter is a major cause of faecal incontinence. Sphincter repair is the standard surgical treatment. This study was designed to analyse the results of anal sphincter repair, to identify possible predictors of outcome and to investigate the presence of bowel symptoms other than leakage at follow up. PATIENTS AND METHODS: Fifty-five women (median age 39 years, range 24-73 years) who underwent anal sphincter repair between 1986 and 1997 at the University Hospital of Linköping answered a postal questionnaire. Current bowel function, degree of continence and the patients' functional result as worse, unchanged, some improvement, good or excellent were assessed. Good or excellent function was regarded as a successful result, the rest as failure. Age, duration of symptoms, type of surgery, morbidity and length of follow up were analysed in relation to outcome. Results of pre- and post-operative anal manometry, endoanal ultrasound, anal sphincter electromyography and pudendal nerve function were also analysed. RESULTS: After a median (range) follow-up period of 40 months (5-137) months, 31 (56%) patients rated the result as either excellent (n=10) or good (n=21). Twenty-one (38%) patients rated the result as some improvement (n=14), unchanged (n=6) or worse (n=1). In three (5%) patients a colostomy was fashioned because of failure. Patients >50 years at surgery (n=18) had a worse outcome (P=0.001). Successful outcome was correlated to increased squeeze pressures post-operatively. The presence of post-operative urgency (P=0.01) and loose stools (P=0.02) was more common in patients with poor outcome. Eight patients became continent to formed and liquid stool.

Journal Article↗

PubMed2001

Measurement of anal sphincter muscles: endoanal US, endoanal MR imaging, or phased-array MR imaging? A study with healthy volunteers.

PURPOSE: To compare endoanal ultrasonography (US), endoanal magnetic resonance (MR) imaging, and phased-array MR imaging for anal sphincter muscle measurement. MATERIALS AND METHODS: Sixty healthy volunteers underwent 1.5-T phased-array MR, endoanal MR, and endoanal US examinations. Sphincter muscle thicknesses were measured. Measurement reliability was analyzed, and correlations among the imaging methods were calculated. Multivariate analysis was performed to assess the influence of age, weight, height, sex, parity, and obstetric trauma on sphincter dimensions. RESULTS: Both MR methods had good reliability for measurements of all sphincter components, whereas endoanal US was reliable for internal sphincter measurement only. There was little correlation between the techniques, except between the two MR techniques, with a strong correlation for total sphincter and perineal body thickness. The internal sphincter thickened significantly (P =.002) with age at endoanal US and endoanal MR imaging but not at phased-array MR imaging. There were small sex-based differences in sphincter muscle measurements at phased-array MR imaging only. CONCLUSION: Endoanal US enables reliable measurement of only internal sphincter thickness, whereas both MR imaging methods enable reliable measurement of all sphincter components. Sphincter measurement with phased-array MR imaging is as reliable as that with endoanal MR imaging.

Adult↗

PubMed2000

Long-term results of electromyographic biofeedback training for fecal incontinence.

PURPOSE: The aim of this study was to examine the long-term results of electromyographic biofeedback training in fecal incontinence. METHODS: Thirty-seven patients (1 male) received a customised program of 2 to 11 (median, 3) biofeedback training sessions with an anal plug electromyometer. Nine patients had persistent incontinence after anal sphincter repair, a further 8 patients had postsurgical or partial obstetric damage of the sphincter but no sphincter repair, 9 patients had neurogenic sphincter damage, and 11 patients were classified as having idiopathic fecal incontinence. Duration of voluntary sphincter contraction was measured by anal electromyography (endurance score) before and after treatment. A postal questionnaire was used to investigate the following variables: 1) subjective rating on a four-grade Likert-scale of the overall result of the biofeedback training; 2) incontinence score (maximum score is 18, and 0 indicates no incontinence); and 3) rating of bowel dissatisfaction using a visual analog scale (0 to 10). RESULTS: Twenty-two patients (60 percent) rated the result as very good (n = 8) or good (n = 14) immediately after the treatment period. Median endurance score improved from 1 to 2 minutes (P < 0.0001). Median incontinence score improved from 11 to 7, and bowel dissatisfaction rating improved from 5 to 2.8 (both P < 0.0001). After a median follow-up of 44 (range, 12-59) months, 15 patients (41 percent) still rated the overall result as very good (n = 3) or good (n = 12). The incontinence score did not change during follow-up. Median bowel dissatisfaction rating deteriorated from 2.8 to 4.2 but remained better than before treatment. Poor early subjective rating and the need for more than three biofeedback sessions were predictive of worsening during follow-up. CONCLUSION: We think it is encouraging that in this study biofeedback treatment for fecal incontinence with an intra-anal plug electrode resulted in a long-term success rate in nearly one-half of the patients.

Adult↗

PubMed1989

[Septic sacroiliitis].

Three patients are described with septic sacroiliitis caused by Staphylococcus aureus, two occurring spontaneously and a third following septic thrombophlebitis. The diagnosis and treatment of this rather rare disease are discussed based upon our findings and the literature data.

Adolescent↗