Anal Sphincter Function Research Articles

Simplified solid sphere test to investigate anal sphincter strength in patients with anorectal diseases.

The solid sphere test has not gained general acceptance to investigate anal sphincters, despite its simplicity and low cost. We studied continent and incontinent patients to evaluate whether the solid sphere test is suitable in assessment of anal sphincter function. Seventy colorectal patients with anal incontinence of varying severity were studied by means of incontinence grading, solid sphere test, and anal manometry. Anal sphincter strength, studied using the solid sphere test, declined gradually with increasing severity of anal incontinence from 1,186 (+/- 334, SD) g in 28 continent patients to 619 (+/- 256, SD) g in 13 patients with daily soiling (P < 0.001). The test also correlated with anal manometry; there was positive correlation with maximum basal pressure (r = 0.643, P < 0.001) and maximum voluntary contraction pressure (r = 0.393, P < 0.01). The solid sphere test is useful in the primary assessment of patients with anal incontinence as a screening test, but alone it is too inaccurate for clinical decision making.

Treatment of rectal cancer by low anterior resection with coloanal anastomosis.

Our institution's experience with low anterior resection in combination with coloanal anastomosis (LAR/CAA) for primary rectal cancer was reviewed (1) to determine cancer treatment results, 2) to identify risk factors for pelvic recurrence, and 3) to assess the long-term success of sphincter preservation. Use of sphincter-preserving resection for mid-rectal and selected distal-rectal cancers continues to increase. As surgical techniques and adjuvant therapy evolve, treatment results must be carefully assessed. One hundred thirty-four patients treated for primary rectal cancer by LAR/CAA between 1977 and 1990 were studied retrospectively. All pathologic slides were reviewed. Median follow-up was 4 years. Actuarial 5-year survival for all patients was 73%. Among 36 patients who relapsed, distant metastatic disease had developed at the time of first clinical relapse in most (86%). Pelvic recurrence was detected in 13 patients, an actuarial rate of 11% at 5 years. Mesenteric implants, positive microscopic resection margin, T3 tumor, perineural invasion, blood vessel invasion, and high tumor grade were associated with increased risk for pelvic recurrence. Eleven patients ultimately required permanent colostomy, and in eight instances the cause was pelvic recurrence. Low anterior resection combined with coloanal anastomosis provides good treatment for mid-rectal cancers and for some distal rectal cancers. Pelvic recurrence is not associated with short distal resection margins but is correlated with the presence of histopathologic markers of aggressive disease in the primary tumor. Long-term preservation of anal sphincter function depends primarily on control of pelvic tumor and can be achieved in more than 90% of patients.

Effect of pregnancy on anal sphincter morphology and function

Twenty pregnant women were investigated prospectively to establish if pregnancy had any effect on the function and morphology of the anal sphincters. Anal endosonography and manometry were performed during pregnancy and 6 weeks after Caesarean section. Muscle thickness of the puborectalis, longitudinal muscle, internal and external anal sphincter were measured. There was no significant difference in the muscle thickness of either before and after Caesarean delivery. The maximum resting pressure and the maximum squeeze pressure were not significantly changed. No significant correlation was found between anal pressure and muscle thickness of either sphincter. Pregnancy itself does not have a significant effect on anal sphincter morphology or function. Any changes in sphincter function that occur in relation to pregnancy or delivery are likely to be due to mechanical trauma rather than hormonal changes in pregnancy.

Incidence of Major Complications of Neurolytic Coeliac Plexus Block

The number of neurolytic coeliac plexus blocks carried out in England and Wales over a 5 year period (1986-1990) was ascertained. The number of cases of the major complications of permanent paraplegia and/or loss of anal and bladder sphincter function following on from such blocks, over the same period of time, was also ascertained. The information was obtained by means of a questionnaire which was sent to most of the pain clinics in England and Wales. There were 2730 neurolytic blocks carried out over the 5 year period. The number of cases of permanent paraplegia following on from the blocks was four. Of these four cases, three of them also had loss of anal and bladder sphincter function--loss of sphincter function never occurred in isolation. The incidence of major complications following neurolytic coeliac plexus block was thus one case per 683 blocks.

Multiple sclerosis: assessment of colonic and anorectal function in the presence of faecal incontinence.

Six females suffering from Multiple Sclerosis (MS) with symptoms of constipation and faecal incontinence were investigated using anal manometry, proctometrogram, proctography and large bowel transit time estimates (using inert markers). Results were compared to a control group (4 females, 2 males). Resting anal sphincter pressure (internal sphincter function) was reduced, but not significantly so, compared with controls (46 +/- 12.6 vs. 68 +/- 8.2 mm Hg: P < 0.1). Maximum squeeze increment pressure (external sphincter function) was significantly diminished in the patient group (13.5 +/- 4.5 vs. 82.5 +/- 12.3 mm Hg: P < 0.0001). Radiological imaging of the anorectum demonstrated an abnormal position of the pelvic floor at rest, with moderate descent in most cases during straining. Measurement of anorectal angles (puborectalis muscle function) indicated a normal angle at rest (76 +/- 10.4 degrees), but with little change on maximum contraction (74 +/- 3.5 degrees) and on straining (79 +/- 4.6 degrees). Rectal sensory parameters did not differ from controls either for minimum sensation, 44.5 +/- 5.2 vs. 30 +/- 5.8 ml (P < 0.1), or at maximum tolerable volume, 163 +/- 34.5 vs. 148 +/- 22 ml (P > 0.2). Four of six patients failed to empty 100% of simulated stool at proctography, at which the only anatomical defect was the presence of a rectocele in two patients. Large bowel transit studies revealed abnormally slow transit in 82% of patients, all of whom had delay in the distal colon. These physiological studies demonstrate that in patients with MS who had anorectal dysfunction, there is a marked impairment of external anal sphincter function with moderate changes in pelvic floor musculature.(ABSTRACT TRUNCATED AT 250 WORDS)

Anal manometry in patients with fissure-in-ano before and after internal sphincterotomy.

The motility pattern of the internal anal sphincter was estimated manometrically in 42 patients with fissure-in-ano before and after left lateral internal sphincterotomy (LAS). Resting anal pressure and anal pressure during straining were significantly higher in patients than in controls (132 +/- 21 SD cmH2O vs 81 +/- 14 SD cmH2O P < 0.0002 and 46 +/- 16 SD cmH2O vs 13 +/- 4 SD cmH2O P < 0.0005), but were normal after LAS. Slow waves were more common in fissure patients (86 +/- 6 SD% of total recording time vs 68 +/- 11 SD% of total recording time, P < 0.0002), but also became normal after successful treatment. The presence of ultra slow waves was also more common in fissure patients (P < 0.0001), and although it was significantly reduced postoperatively (P < 0.0001), it did not return to normal. Sampling was less frequent in fissure patients (P < 0.0001) and improved significantly after successful treatment (P < 0.0002). Rectal distension produced significantly less reduction in anal pressure in fissure patients as compared to controls (P < 0.01), but successful treatment returned the response to normal. There were 2 patients with anal fissure who did not heal after left LAS. Those patients and a further 5 patients with non healed fissures after left LAS showed the same pathological manometric features as before surgery. Their fissures were successfully treated by additional right lateral internal sphincterotomy. In conclusion, increased internal sphincter activity is probably an aetiological factor in fissure-in-ano, while successful LAS improves anal sphincter function.(ABSTRACT TRUNCATED AT 250 WORDS)

Anorectal dysfunction and delayed colonic transit in patients with progressive systemic sclerosis.

We studied 14 unselected patients with progressive systemic sclerosis (PSS), six with constipation, and eight with normal bowel habits. A control group, matched for age and sex, comprised six patients with idiopathic constipation and seven healthy subjects. Anorectal manometry was performed with perfused catheters and segmental colonic transit was measured by a radiopaque marker technique. The resting pressure of the anal canal was significantly reduced in PSS with constipation (P < 0.05). The rectoanal inhibitory reflex was detected in only one PSS patient with constipation, but was present in seven of eight PSS patients with normal bowel habits and in all controls (P < 0.01). Total and right colonic transit times were significantly delayed in PSS with constipation and in patients with idiopathic constipation (P < 0.05). In patients with PSS, colonic transit was delayed and anal sphincter function was impaired in constipated patients, suggesting involvement of both the colon and the anorectum by the disease.

Treatment of colonic bleeding in Klippel-Trenaunay syndrome with combined partial colectomy and endoscopic laser

Klippel-Trenaunay syndrome can be associated with significant lower gastrointestinal bleeding from diffuse cavernous hemangiomata of the colon. Distal colectomy is curative but the formation of a colostomy is undesirable in patients who already have a poor self-image due to the other manifestations of Klippel-Trenaunay syndrome such as multiple cutaneous hemangiomata, severe varicose veins, and prominent limb hypertrophy. Endoscopic laser ablation alone is often not feasible in these patients because of the extensive and often circumferential nature of the colonic hemangiomata. This report describes successful treatment of gastrointestinal hemorrhage due to colonic hemangiomata by a novel combination of partial colonic resection and endoscopic laser therapy. Case 1 demonstrates that endoscopic laser ablation of the diseased colonic mucosa, while not feasible with the extensive involvement of the left colon, was very effective when combined with partial colectomy at curing the bleeding while maintaining anal sphincter function. In case 2 the disease was more limited and more easily amenable to endoscopic laser ablation. Combined surgical and laser endoscopic therapy is recommended in treating the colonic hemangiomata associated with Klippel-Trenaunay syndrome.

Incidence of Major Complications of Neurolytic Coeliac Plexus Block

The number of neurolytic coeliac plexus blocks carried out in England and Wales over a 5 year period (1986-1990) was ascertained. The number of cases of the major complications of permanent paraplegia and/or loss of anal and bladder sphincter function following on from such blocks, over the same period of time, was also ascertained. The information was obtained by means of a questionnaire which was sent to most of the pain clinics in England and Wales. There were 2730 neurolytic blocks carried out over the 5 year period. The number of cases of permanent paraplegia following on from the blocks was four. Of these four cases, three of them also had loss of anal and bladder sphincter function--loss of sphincter function never occurred in isolation. The incidence of major complications following neurolytic coeliac plexus block was thus one case per 683 blocks.

Diversion colitis and involution of the defunctioned anorectum.

To measure the effects of defunction in the anorectum, 12 patients (seven men and five women aged 59 (44-81) years) were studied after the Hartmann operation. The operation was for septic complications of diverticular disease in nine and sigmoid carcinoma in three patients. Physiology studies were undertaken 1 and 3 months after surgery, and diversion colitis was assessed endoscopically and by mucosal biopsy at 3 months. There was no change in anal sphincter function by three months. Proctometrogram studies, however, showed an appreciable decrease in rectal volume in all cases, by a mean of 35% of the 1 month volume. The maximum tolerable volume at 1 month was 157 (111-210) ml and at 3 months 87 (71-145) ml; p < 0.01. There was no change in rectal sensation or compliance. Erythema and granularity without gross erosions or ulceration were found at endoscopy. Histology showed abnormalities in all cases by 3 months. The characteristic features were of a chronic inflammatory cell infiltrate with surface exudate, microscopic erosions, and lymphoid follicular hyperplasia. Crypt abscesses were not a feature at this stage and there was no distortion of crypt architecture. After defunction the previously normal rectum is affected by diversion colitis which, at 3 months, is mild but has characteristics that distinguish the changes from those of inflammatory bowel disease. It is associated with progressive rectal stump involution.

Effect of Anoreceptive Intercourse on Anorectal Function

This study is the first published assessment of the effect of anoreceptive intercourse (ARI) on anal sphincter tone and function. Forty anoreceptive (AR) male homosexuals were compared with 18 age matched non-anoreceptive (non-AR) heterosexual males. Subjects were questioned about ARI, defaecation and faecal incontinence. Anal resting pressure, maximum voluntary squeeze pressure, anal mucosal electrosensitivity, perineal descent and rectal sensation were measured in all subjects. Fourteen of the AR subjects but only one of the non-AR subjects had symptoms of frequent anal incontinence (P < 0.05). There was a significant reduction in both maximum anal resting pressure (P < 0.01) and anal mucosal electrosensitivity (P < 0.05) and a significant difference in the anal resting pressure profile (P = 0.02) in the AR subjects compared with the non-AR subjects. There was a significant reduction in maximum squeeze pressure in AR subjects with anal incontinence compared with either AR subjects without anal incontinence (P < 0.01) or non-AR subjects (P < 0.01). There were no significant differences in stoll consistency, frequency of defaecation, perineal descent or rectal sensation between the groups. ARI is associated with reduced resting pressure in the anal canal and an increased risk of anal incontinence. The risk of incontinence is greatest amongst AR subjects with reduced maximum squeeze pressure.

External radiation therapy without chemotherapy in the management of anal cancer

Most therapeutic regimens currently in use for sphincter preservation in anal cancer utilize combined radiation therapy and chemotherapy. To provide a basis for comparison with combined therapy results, an analysis was made of patients treated with external radiation therapy without chemotherapy. Eighteen patients with squamous cell, basaloid, or cloacogenic carcinoma of the anal canal were treated with external radiation therapy between January 1, 1980, and December 31, 1989, with the goal of sphincter preservation and cure. Before radiation therapy, five patients had incisional biopsies, two underwent piecemeal removal of the tumor, three had excisional biopsies with positive margins, five had excisional biopsies with negative margins, and three had excisional biopsies with unknown margins. All patients received 45 to 50 Gy in 25 to 28 fractions to the pelvis and perineum, and 16 of the 18 received an additional boost to the primary site to bring the total dose to 55 to 67 Gy in 30 to 38 fractions. With follow-up of 2.5 to 11.2 years in surviving patients, 5-year projected survival and freedom from local recurrence were 94% and 100%, respectively. Two patients required a temporary colostomy because of treatment complications. No patient required a permanent colostomy or had permanent loss of anal sphincter function as a result of local recurrence or complications. These results, combined with others, suggest that external radiation therapy without chemotherapy is an acceptable alternative to combined radiation therapy and chemotherapy in the management of anal cancer.

Patterns of recurrence following high-dose preoperative radiation and sphincter-preserving surgery for cancer of the rectum

High-dose preoperative radiation with new sphincter-preserving surgical options for the management of distal and unfavorable cancers of the rectum is gaining recognition as an alternative to abdominoperineal resection and permanent colostomy. From 1976 to 1989, 161 patients with cancer of the rectum were entered into a program of high-dose preoperative radiation and radical sphincter-preserving surgery. Selection was based on prospective clinical staging of unfavorability or tumor location at a low level in the rectum. All patients received a minimum dose of 4,000 to 4,500 cGy over 4 1/2 weeks in fractional doses of 180 to 250 cGy. Patients with tumor fixation were given an additional boost of 1,000 to 1,500 cGy for a total of 5,500 to 6,000 cGy using a coned-down field. Surgery was carried out four to eight weeks following completion of radiation. Fourteen patients, found at surgery to have liver metastasis, were treated by palliative resection. One hundred forty-seven patients underwent radical curative surgery with sphincter preservation. The surgical procedures performed were combined abdominotranssacral resection (63), transanal-abdominal-transanal resection (53), and anterior resection (31). Follow-up ranged from a minimum of two years to 15 years, with a median of five years. There was no perioperative mortality. Anastomotic failure occurred in three patients, two of whom were reconstituted. Late diversion was required in 10 other patients, primarily for recurrent disease. One hundred thirty-four of the 147 patients (91 percent) maintained long-term normal sphincter function. Pelvic-perineal recurrence was observed in 18 patients (12.4 percent), 12 of whom had fixed tumors located below the 6-cm level of the distal rectum. Median time to local recurrence was 24 months. Distant metastasis with or without local recurrence occurred in 35 patients, 22 of whom had fixed tumors below the 6-cm level of the rectum. Median time to distant metastasis was 17 months. Forty-three patients have died, 32 of disease. The overall five-year Kaplan-Meier actuarial survival for the total group of patients is 79 percent, with a disease-free survival of 73 percent. The findings of this study indicate that high-dose preoperative radiation used in combination with radical sphincter-preserving surgical techniques results in excellent local control of disease, improved survival, and enhanced quality of life with retention of normal anal sphincter function.

Laser Cytoreduction as Part of Multimodality Therapy for Squamous Cell Carcinoma of the Anus: A Case Report

ABSTRACT The treatment of anal canal epidermoid cancer has changed dramatically during the last two decades, exemplified by the excellent results of primary chemoradiotherapy compared with traditional radical surgical resection. Despite this progress, the management of large (>5 cm) tumors remains controversial. We report a case of advanced (tumor size 8 cm, lymphatic metastases; Stage T4N2), moderately differentiated squamous cell carcinoma of the anal canal which was managed by CO2 laser ablation with followup combined chemoradiotherapy. The patient has remained well in the 12 months since initial treatment with excellent anal sphincter function and no evidence of distant metastases or residual disease on biopsy. We conclude that combined debulking and chemoradiotherapy should be considered in patients with locally advanced, unfavorable squamous cell cancer of the anal canal.

The results of pouch surgery after ileo-anal anastomosis for inflammatory bowel disease: the manometric assessment of pouch continence and its reservoir function.

Anal sphincter function after restorative proctocolectomy has mainly been investigated by anal manometry. A significant decrease of basal pressure up to 45%, has been recorded postoperatively, possibly due to sphincter stretch during endoanal mucosectomy. Both abdominal mucosectomy and anastomosis at the level of the anorectal ring have been reported to prevent anal sphincter damage and lead to better continence. The striated sphincter is not significantly affected by the surgical procedure. Pouch-anal inhibitory reflex is partly maintained in the presence of a rectal cuff which leaves the ganglionic plexus unaltered; a satisfactory continence is also retained in the absence of the reflex when the rectum is totally excised. Pouch capacity, compliance and motility have been investigated by endoluminal balloon and probes. Pouch emptying has been studied by a "porridge" test, by a semi-solid medium labelled with technetium-99, and by other methods. A more effective storage function is achieved by large capacity reservoirs which lower the bowel frequency. The motor response to pouch distension, to a meal, and to pharmacological stimuli is usually counteracted by sphincter contraction. Ileal hypermotility may lead to fecal leakage mainly in the presence of weak sphincters. Poor pouch emptying may be related to an anal stricture.

Induction chemotherapy with carboplatin and 5-fluorouracil in combination with radiotherapy in loco-regionally advanced epidermoid carcinoma of the anus--preliminary results.

During the last decade conservative treatment of anal carcinoma based on radiotherapy has gained popularity. Radiotherapy is often combined with concurrent chemotherapy although no firm evidence exists that such combinations are more effective than radiotherapy alone. Treatment results with respect to anal sphincter function are generally better for small tumors. In an effort to improve the treatment results for locally advanced epidermoid anal carcinoma, a selection of patients with such tumors has been treated with induction chemotherapy comprising two or three courses of a combination of carboplatin 300-350 mg/m2 i.v. and 5-fluorouracil 1,000 mg/(m2 x d) x 5 d prior to radiotherapy. Six female patients aged 37 to 74 have completed the regimen. All had complete tumor regressions at conclusion of radiotherapy. No recurrence has yet occurred but the follow-up period is still short (8-21 months). No interruption of chemotherapy due to toxic side effects was necessary and no severe toxicity registered. Further study is needed to evaluate the efficacy and toxicity of the regimen, but these early findings are promising.

Idiopathic fecal incontinence

Pelvic floor dysfunction is related to neuropathic injury to the pelvic floor musculature. Clinically, the patient may present with genital prolapse or urinary or fecal incontinence. For a successful outcome, the physician must consider all pelvic compartments in the evaluation and treatment of patients with these disorders. Disorders of the posterior compartment are the least familiar to the gynecologist. Idiopathic fecal incontinence, a posterior compartment defect, is defined as a progressive deterioration of anal sphincter function in patients with no history of sphincter damage. This review discusses the latest findings about idiopathic fecal incontinence within the context of pelvic floor dysfunction and neuropathy.

Dynamic anal manometry: Physiological variations and pathophysiological findings in fecal incontinence

A recently developed technique for dynamic anal manometry was used to study 40 healthy volunteers and 23 patients with fecal incontinence. Seven parameters of anal function were measured. Intraindividual variation of the parameters was studied in 5 females and 5 males. The results of dynamic anal manometry were compared with standard pull-through static anal manometry and correlated well. During opening of the anal sphincter at rest, compliance increased with increasing distension. Males had higher maximal closing pressures during squeeze and lower anal compliance during squeeze than females. There was no sex differences of the sphincter measurements at rest. Age had little effect, and gender had no effect on the measurements. With standard anal manometry, 6 of 23 patients with fecal incontinence both had maximal resting pressure and maximal squeeze pressure within the normal range. When dynamic anal manometry was used, all 23 patients showed one or more abnormal values. The method of dynamic anal manometry provides an opportunity for a more thorough assessment of anal sphincter function than previous manometric methods.

Recovery of anal sphincter function following transabdominal repair of rectal prolapse

Twenty-eight patients with complete rectal prolapse underwent anorectal manometry before and 6 months and 1-2 years after abdominal rectopexy and sigmoid resection in a study of the mechanisms responsible for postoperatively improved anal continence. Preoperatively, 22 patients reported defective and control. Seven patients (all with minor incontinence) regained normal control and eight other patients achieved improved continence after surgery. Anal resting, squeeze, and voluntary contraction pressures were significantly lower for defective than for normal control, with a significant rise in these pressures at 6 months after the operation, except for those incontinent patients in whom continence was not improved. No further pressure rise was seen later. Improvement of continence was not accompanied by changes in rectal sensation or reflexive functions of the internal anal sphincter. These results suggest that recovery of the resting and voluntary contraction functions of the sphincter muscles was the cause of continence improvement observed after surgery. Anal manometry was unable to predict outcome of function. Therefore, supplementary procedures for restoration of continence are not advisable, although patients with only minor incontinence are likely to regain full continence after rectopexy alone.

Three-Dimensional Imaging of the Anal Sphincter

Anorectal dysfunction can be an extreme embarrassment and inconvenience to persons afflicted with the condition, disrupting their lifestyle. Evaluation of the anal sphincter and the distinction between muscular and neural etiology is essential. Three-dimensional imaging of the anal sphincter by use of anorectal manometry with an eight-port perfused catheter combined with computer analysis aids in defining anal sphincter function. The use of three-dimensional imaging is valuable to the physician in the determination of the presence of a muscular defect, the location of the defect and the appropriateness of surgical intervention to resolve the anal dysfunction.