Internal Sphincter (internal + sphincter)

Distribution by Scientific Domains


Selected Abstracts


Is the Male Dog Comparable to Human?

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2002
A Histological Study of the Muscle Systems of the Lower Urinary Tract
Because of their superficial anatomical resemblance, the male dog seems to be suitable for studying the physiologic and pathological alterations of the bladder neck of human males. The present study was carried out to compare and contrast the muscular anatomy of the male dog lower urinary tract with that of humans. The complete lower urinary tract, including the surrounding organs (bulb of penis, prostate, rectum and musculature of the pelvic floor) were removed from adult and newborn male dogs and histologically processed using serial section technique. Based on our own histological investigations, three-dimensional (3D)-models of the anatomy of the lower urinary tract were constructed to depict the corresponding structures and the differences between the species. The results of this study confirm that the lower urinary tract of the male dog bears some anatomical resemblance (musculus detrusor vesicae, prostate, prostatic and membranous urethra) to man. As with human males, the two parts of the musculus sphincter urethrae (glaber and transversostriatus) are evident in the canine bladder neck. Nevertheless, considerable differences in formation of individual muscles should be noted. In male dogs, no separate anatomic entity can be identified as vesical or internal sphincter. The individual course of the ventral and lateral longitudinal musculature and of the circularly arranged smooth musculature of the urethra is different to that of humans. Differences in the anatomy of individual muscles of the bladder neck in the male dog and man suggest that physiological interpretations of urethral functions obtained in one species cannot be attributed without qualification to the other. [source]


Faecal incontinence after lateral internal sphincterotomy is often associated with coexisting occult sphincter defects: A study using endoanal ultrasonography

ANZ JOURNAL OF SURGERY, Issue 10 2001
Joe J. Tjandra
Background: Troublesome faecal incontinence following a lateral internal sphincterotomy (LIS) is often attributed to faulty surgical techniques: division of excessive amount of internal sphincter or inadvertent injury to the external sphincter. The aim of the present paper was to assess the anatomic and physiological factors that may contribute to faecal incontinence following a technically satisfactory lateral internal sphincterotomy by a group of colorectal specialists. Methods: Fourteen patients (nine women, five men; median age: 38 years; range: 23,52 years) who developed troublesome postoperative faecal incontinence were evaluated by clinical assessment, endoanal ultrasonography and anorectal physiological studies (manometry, pudendal nerve terminal motor latency) by two independent observers. The Cleveland Clinic continence score (0,20; 0, perfect continence; 20, complete incontinence) was used to quantify the severity of faecal incontinence. Fourteen continent subjects after a LIS (nine female patients, five male patients; median age: 36 years; range: 20,44 years) were also evaluated as ,continent' controls (continence score , 4). Results: In the incontinent group, the median postoperative Cleveland Clinic continence score was 9 (range: 6,13) compared with a preoperative score of 1 (range: 0,3). On assessment by endoanal ultrasonography the site of the internal sphincterotomy was clearly identified. There were additional coexisting defects, on endoanal ultrasonography, of the external anal sphincter in seven female patients, of the internal sphincter in two female and two male patients; and a defect of both the external and internal sphincters in a male patient who had had a prior fistulotomy. The pudendal nerve terminal motor latency (PNTML) was prolonged in two female patients on the side contralateral to the lateral internal sphincterotomy. In two of five male patients there was no evidence of any occult sphincter injuries. In the continent controls a defect of the distal portion of the external sphincter was noted in one female patient. None of the patients had a prolonged PNTML. The maximum voluntary contraction was significantly lower in the female subjects than in the female continent controls (92 mmHg vs 140 mmHg; P < 0.05), while the resting anal canal pressures and length of the high pressure zone were similar between the study subjects and the continent controls. Conclusion: Troublesome faecal incontinence after a satisfactorily performed lateral internal sphincterotomy is often associated with coexisting occult sphincter defects. [source]


Botulinum toxin for recurrent anal fissure following lateral internal sphincterotomy,

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 6 2008
G. Brisinda
Background: The aim of the study was to evaluate the efficacy of botulinum toxin injection in the treatment of recurrent anal fissure following lateral internal sphincterotomy. Methods: Eighty patients were treated with botulinum toxin (30 units Botox® or 90 units Dysport®), injected into two sites of the internal sphincter. Clinical and manometric results were recorded before and after treatment. If symptoms persisted at 2 months, the examiners could decide to re-treat the patient. The same preparation of serotype A of botulinum neurotoxin was used for reinjection. Results: One month after injection there was complete healing in 54 patients (68 per cent). Eight patients (10 per cent) reported mild incontinence of flatus that had disappeared spontaneously within 2 months. At 2 months, 59 patients (74 per cent) had a healing scar. After reinjection, 11 of 21 re-treated patients reported mild incontinence to flatus that lasted for a few weeks and resolved spontaneously. Anorectal manometry at 1 month demonstrated a significant reduction in both resting anal pressure and maximum voluntary squeeze pressure (P < 0·001). There were no relapses during a mean value of 57·9 months of follow-up. Conclusion: Botulinum toxin is efficacious in patients with recurrent anal fissure following lateral internal sphincterotomy. Copyright © 2008 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source]


Botulinum toxin reduces anal spasm but has no effect on pain after haemorrhoidectomy

COLORECTAL DISEASE, Issue 2 2009
B. Singh
Abstract Objective, Pain following haemorrhoidectomy is due to a combination of factors including spasm of the internal sphincter, an open wound and local infection. In this study, we investigated the effect of botulinum toxin on postoperative pain following Milligan,Morgan haemorrhoidectomy. Method, A prospective randomized controlled trial was conducted in 32 patients undergoing haemorrhoidectomy. Routine postoperative care included metronidazole and bupivacaine. Patients were also given an inter-sphincteric injection of either placebo or botulinum toxin (150 units). Maximal resting pressure (MRP) and maximal squeeze pressure (MSP) were measured postoperatively. A linear analogue score was used to assess postoperative pain. The sample size calculation was calculated to show one standard deviation difference between groups. The primary endpoint was reduction in postoperative pain. Results, The MRP was significantly lower in the botulinum toxin group (mean 50.5 mmHg; 95% CI 39.77,61.23) compared with the placebo group (mean 64.94 mmHg; 95% CI 55.65,74.22) (P = 0.04) at week 6. At week 12 there was no significant difference in MRP between the two groups. In contrast MSP was significantly lower in the botulinum toxin group at weeks 6 and 12 (mean 87.1 mmHg; 95% CI 66.9,107.1) compared with the placebo group (mean 185.8 mmHg; 95% CI 134.2,237.4) at week 12 (P = 0.0014). There was no significant effect on overall or maximal pain scores. Median time for return to normal activities was not significantly different between groups. Conclusion, Botulinum toxin reduces anal spasm but has no significant effect on postoperative pain. [source]


Faecal incontinence after lateral internal sphincterotomy is often associated with coexisting occult sphincter defects: A study using endoanal ultrasonography

ANZ JOURNAL OF SURGERY, Issue 10 2001
Joe J. Tjandra
Background: Troublesome faecal incontinence following a lateral internal sphincterotomy (LIS) is often attributed to faulty surgical techniques: division of excessive amount of internal sphincter or inadvertent injury to the external sphincter. The aim of the present paper was to assess the anatomic and physiological factors that may contribute to faecal incontinence following a technically satisfactory lateral internal sphincterotomy by a group of colorectal specialists. Methods: Fourteen patients (nine women, five men; median age: 38 years; range: 23,52 years) who developed troublesome postoperative faecal incontinence were evaluated by clinical assessment, endoanal ultrasonography and anorectal physiological studies (manometry, pudendal nerve terminal motor latency) by two independent observers. The Cleveland Clinic continence score (0,20; 0, perfect continence; 20, complete incontinence) was used to quantify the severity of faecal incontinence. Fourteen continent subjects after a LIS (nine female patients, five male patients; median age: 36 years; range: 20,44 years) were also evaluated as ,continent' controls (continence score , 4). Results: In the incontinent group, the median postoperative Cleveland Clinic continence score was 9 (range: 6,13) compared with a preoperative score of 1 (range: 0,3). On assessment by endoanal ultrasonography the site of the internal sphincterotomy was clearly identified. There were additional coexisting defects, on endoanal ultrasonography, of the external anal sphincter in seven female patients, of the internal sphincter in two female and two male patients; and a defect of both the external and internal sphincters in a male patient who had had a prior fistulotomy. The pudendal nerve terminal motor latency (PNTML) was prolonged in two female patients on the side contralateral to the lateral internal sphincterotomy. In two of five male patients there was no evidence of any occult sphincter injuries. In the continent controls a defect of the distal portion of the external sphincter was noted in one female patient. None of the patients had a prolonged PNTML. The maximum voluntary contraction was significantly lower in the female subjects than in the female continent controls (92 mmHg vs 140 mmHg; P < 0.05), while the resting anal canal pressures and length of the high pressure zone were similar between the study subjects and the continent controls. Conclusion: Troublesome faecal incontinence after a satisfactorily performed lateral internal sphincterotomy is often associated with coexisting occult sphincter defects. [source]