Sacral neuromodulation for the management of severe constipation: development of a constipation treatment protocol.

BACKGROUND: Constipation is a common multifactorial gastrointestinal symptom with quality of life implications. Sacral neuromodulation has been used in the management of severe constipation with mixed results. The aim of this study was to review our experience of sacral neuromodulation as a treatment for chronic constipation and develop a chronic constipation management protocol. METHODS: In patients with severe constipation, failure of conservative management including biofeedback and rectal irrigation were considered for neuromodulation. Temporary stimulation lead was placed in the sacral foramen of eligible patients and pre and post stimulation bowel diaries were compared. Patients with ≥50% improvement in bowel diaries had permanent implant. Patients were followed up at 2 and 4 weeks, 3, 6, and 12 months, and then yearly with bowel diaries. RESULTS: Temporary neuromodulation wires were implanted in 21 patients (20 female). Significant bowel diary improvement was seen in 12 (57%) patients (p < 0.01). Eleven permanent implants have been performed. Improvement in symptoms was lost in one patient. No major side effects were observed. Three patients have had reoperations (one wire fracture, one reposition of battery, and one poor initial lead placement). Improvements in bowel diaries have been maintained over a median follow-up period of 38 months (18-62 months). CONCLUSION: Sacral neuromodulation can provide long-term symptom relief in selected patients with severe constipation. Sacral neuromodulation should be incorporated into the treatment algorithm for chronic constipation.

A new method of assessing anal sphincter integrity using inverted vectormanometry.

PURPOSE: Vectorgraphy as an integrated mapping of radial pressure profiles of the anal canal has been used to attempt identification of pressure-related defects with doubtful reliability since vectorgraphs bear no resemblance to endoanal ultrasound scans at similar levels in the anal canal. This study aimed to devise a technique to enable vectorgraphy to be more representative of sphincter function and integrity. METHODS: Vectormanometry was performed in 50 patients with anorectal disorders using an Arndorfer pneumohydraulic system. "Normal" three-dimensional manometric images of each 0.5 cm of the anal sphincter were computer-generated by plotting anal pressures at rest and during squeeze radially around a central zero axis. The graphs were replotted with zero at the periphery and maximal anal pressure at the center. Both this ("inverted") and "normal" vectorgraphs were compared with endoanal ultrasound images at similar levels, assessing both internal and external anal sphincters. RESULTS: Standard vectormanometry produced excellent pictures of pressures throughout the anal canal; the anatomy however bore no resemblance to the pictures produced by endoanal ultrasound. The inverted vectographs showed a much better correlation with endoanal ultrasound at each 0.5-mm level of the anal canal, for both squeeze pressure graphs and external sphincter correlations and for resting pressure graphs and internal sphincter correlations. CONCLUSIONS: Accurate assessment of sphincter integrity is not possible when interpreting the vectormanometry graphs in the current format; however, inverted vectorgraphy gives good correlations with endoanal ultrasound and provides combined functional (pressure measurement) and anatomic (three-dimensional profile) information regarding the anal canal.

Early results of a rotational flap to treat chronic anal fissures.

BACKGROUND: Treatment of anal fissures has changed dramatically in the past decade. Only a few fail to respond to medical therapy. Sphincterotomy and anal dilatation have fallen out of favour due to the risk of incontinence. Island flaps have been proposed to address this, but 60--70% of flap donor sites break down with complications. We proposed that using a rotational flap would overcome this problem. METHODS: Twenty-one patients (14 women,7 men) with chronic anal fissures were treated with rotation flap from perianal skin. The median age was 43 (range 21--76) years. All patients had failed chemical sphincterotomy and showed no signs of improvement following at least a 3-month course of topical GTN 0.2% ointment. RESULTS: The median hospital stay was 2 days. Seventeen patients had complete resolution of symptoms. Only one patient continued to have severe pain. Two developed a recurrent fissure. One patient had a combined fistula-fissure complex at diagnosis and suffered from a breakdown of the flap and donor site. Another patient had had haemorrhoidectomy and an advancement flap in the past. He developed problems with the donor site, which was successfully managed conservatively. One patient had persistent mild pain after surgery, but the cause could not be found. None of the patients suffered continence defects after surgery. CONCLUSION: Use of a rotational flap is a simple, safe and successful treatment for anal fissures. Donor site problems are minimised using this approach. It should be a treatment of choice when surgery is required for chronic anal fissures, particularly in patients in whom there is a risk of incontinence.

Sacral nerve stimulation for faecal incontinence.

Faecal incontinence is a common problem. Conservative measures are effective in a significant proportion of patients. Failure of conservative management has until recently meant recourse to surgical intervention. Surgical treatment is often associated with disappointing results. Recently, sacral nerve stimulation (SNS) has been developed as a minimally invasive, effective technique for idiopathic and acquired faecal incontinence. The technique uses chronic low-level electrical stimulation of the sacral nerves, or neuromodulation, to produce a clinically beneficial effect on the distal colon and rectum, the pelvic floor and the anal sphincter complex. SNS is a 2-stage procedure: a diagnostic stage - temporary percutaneous nerve evaluation (PNE), and a therapeutic stage - permanent SNS. The predictive value of PNE is high, and the surgical trauma and morbidity of both procedures extremely low. The technique has been adapted from its original application in urinary dysfunction. It is almost impossible to produce level 1 evidence for this type of intervention; however, the results are superior to other interventions. Patient selection criteria are evolving, but there is a growing body of evidence that supports its use as first-line treatment for faecal incontinence in patients where conservative measures have failed.

Does laparoscopic abdominoperineal resection of the rectum compromise long-term survival?

PURPOSE: Laparoscopic techniques for bowel resection have not enjoyed widespread popularity. Of concern is that long-term follow-up data of cancer specific outcomes is not yet available. The aim of our study was to examine the long-term outcome of abdominoperineal resection for cancer done laparoscopically compared with a similar cohort who underwent open surgery. METHODS: A retrospective review was performed of all abdominoperineal resections done in our center between 1992 and 2000, comparing the cancer-specific outcomes of the laparoscopic cohort with the open cohort. The analysis was performed on an intention-to-treat basis and survival analysis was calculated by the techniques of Kaplan-Meier. RESULTS: Eighty-nine patients were reviewed. Twenty-eight operations were done laparoscopically, and 61 were open. The two groups were matched for age and stage of disease. There was no difference in mean length of overall survival (open = 30.3 months; laparoscopic = 40.8 months; P = 0.355 log rank). No difference in overall recurrence rate, isolated recurrence rate, or distant recurrence rates was seen nor was there any difference in the disease-free period. There was no difference in the number of lymph nodes harvested from the resected specimens, and the distance to the lateral margins or involvement of tumor in the lateral margins between the two groups was the same. The laparoscopic cohort did have a significantly shorter length of stay (mean, 13 days) compared with the open cohort (mean, 18 days), P = 0.008 Mann-Whitney U test. CONCLUSIONS: Laparoscopic abdominoperineal resection of the rectum for cancer does not compromise cancer-specific survival outcomes. The patients avoid a large abdominal wound, which improves cosmesis and presumably is responsible for the significantly shorter length of stay.

Rectoanal reflex parameters in incontinence and constipation.

PURPOSE: The transient relaxation of the internal anal sphincter in response to rectal distention is believed to play an important role in the continence mechanism. Most anorectal physiology laboratories merely report the rectoanal inhibitory reflex as being either present or absent. This study aimed to assess the parameters of the rectoanal inhibitory reflex in incontinent and constipated patients and healthy control subjects, in an attempt to analyze differences in internal anal sphincter function in these groups. We analyzed each response of the internal anal sphincter to rectal distention with progressively increasing volumes of air at a single site (proximal anal canal). METHODS: Fifty-five constipated and 99 incontinent patients and healthy control subjects underwent manometry. Various parameters of the rectoanal inhibitory reflex were analyzed, and percentage sphincter relaxation was calculated at each volume at which rectoanal inhibitory reflex occurred. RESULTS: There was no difference in the volume of rectal distention required to elicit sensation (P = 0.626) or the rectoanal inhibitory reflex (P = 0.371) in the three groups. There was a significant correlation between the volume required to elicit the rectoanal inhibitory reflex and that at which sensation was first felt only in the incontinent (P = 0.0001) group. Significantly greater sphincter relaxation was seen at each volume (P = 0.001) in the incontinent as compared with the constipated patients. With progressive rectoanal inhibitory reflex, consistently progressive increases in internal anal sphincter relaxation were found only in the incontinent group. This consistent relationship was not seen in the constipated patients or in healthy control subjects. CONCLUSIONS: Assessment of various parameters of the rectoanal inhibitory reflex yielded important information regarding the continence mechanism. Altered responses of the internal anal sphincter in anorectal disorders plays a role in the associated physiologic impairment. This may have significant clinical implications with regard to sphincter-saving resections.

Kinetics of postoperative serum vascular endothelial growth factor (VEGF)--can it be used to predict curative resections in colorectal cancer?

BACKGROUND: Vascular endothelial growth factor (VEGF) is considered to be probably the most important and final mediator of neovascularisation. We have shown that VEGF can predict stage in colorectal cancer (Clin Cancer Res 1998, 17). This study was conducted to study the kinetics of serum VEGF after colorectal resections over ten postoperative days. PATIENTS AND METHODS: The study comprised 154 healthy controls and 108 colorectal resections (79 curative, 15 palliative and 14 benign). Samples were collected at 4-6 hours, days 1,3,5,7 and 10 post surgery. RESULTS: Six-hour levels were significantly lower in the curative group (p < 0.0005) but not in the benign and palliative groups (p = 0.27 and 0.3, respectively). Sensitivity and specificity at 20% cut-off fall in VEGF gives 83.5% sensitivity with 80% specificity in predicting curative resection. CONCLUSION: Early postoperative serum VEGF levels show significant fall and may help to identify the oncological status of colorectal cancer resections.