An experimentally successful new sphincter-conserving treatment for anal fistula.

PURPOSE: A new sphincter-conserving treatment was evaluated in a porcine model. METHODS: A total of 36 fistulas were created by procedures that have been published previously. At fistula induction a skin biopsy was taken from which to culture fibroblasts. Four weeks after induction, when fistulas were well established, the fistula tracks were cored out. Collagen paste modified from Permacol injection (Covidien, Mansfield, MA) was then used as a solitary infill material in 11 tracks, cultured autologous fibroblasts being added to this in a further 18 tracks. The track was cored out in seven controls, but these tracks were not treated with infill material. All of the internal and external openings were closed. Anorectal excision was then carried out under terminal anesthesia at 2 to 12 weeks. Histologic examination of individual tracks was performed by an experienced pathologist. RESULTS: In this quadruped all of the infilled tracks healed, autologous fibroblasts having the best tissue integration, but only two of seven control tracks healed. CONCLUSIONS: Removal of the fistula track followed by injection of collagen healed all of the cases. The addition of autologous fibroblasts improved the histologic appearance of the tracks. A pilot study in human fistula patients is in progress.

Sacral nerve stimulation for fecal incontinence related to obstetric anal sphincter damage.

PURPOSE: Sphincter repair is the standard treatment for fecal incontinence secondary to obstetric external anal sphincter damage; however, the results of this treatment deteriorate over time. Sacral nerve stimulation has become an established therapy for fecal incontinence in patients with intact sphincter muscles. This study investigated its efficacy as a treatment for patients with obstetric-related incontinence. METHODS: Fecally incontinent patients with external sphincter defects who would normally have undergone overlapping sphincter repair as a primary or repeat procedure were included. Eight consecutive women (median age, 46 (range, 35-67) years) completed temporary screening; all eventually had permanent implantation. RESULTS: Six of eight patients had improved continence at median follow-up of 26.5 (range, 6-40) months. Fecal incontinent episodes improved from 5.5 (range, 4.5-18) to 1.5 (range, 0-5.5) episodes per week (P = 0.0078). Urgency improved in five patients, with ability to defer defecation improving from a median of <1 (range, 0-5) minute to 1 to 5 (range, 1 to >15) minutes (P = 0.031, all 8 patients). There was no change in anal manometry or rectal sensation. There was significant improvement in lifestyle, coping/behavior, depression/self-perception, and embarrassment as measured by the American Society of Colon and Rectal Surgery fecal incontinence quality of life score. CONCLUSIONS: Sacral nerve stimulation is potentially a safe and effective minimally invasive treatment for fecal incontinence in patients with de novo external anal sphincter defects or defects after unsuccessful previous external anal sphincter repair, although numbers remain small.

Colorectal cancer in the young patient.

Colorectal cancer is the second most common cause of death from cancer in the UK. It is estimated that between 2 to 3 per cent of colorectal cancer occurs in patients younger than the age of 40 years. It remains unclear from the literature whether this group of patients has a worse prognosis from colorectal cancer than the population as a whole. There are no large series that report a 10-year survival in young patients diagnosed with colorectal cancer. The authors' objective was to assess patients diagnosed with colorectal cancer younger than the age of 40 years to determine whether the 5- and 10-year survival rates in a tertiary referral center compares favorably with survival rates obtained at other centers and the population as a whole. A retrospective observational study was conducted and an analysis of the patient's notes was made, specifically looking at age at diagnosis, nature and duration of symptoms, predisposing risk factors for colorectal cancer, the site within the bowel of the colorectal cancer, the type of curative resection performed, Dukes' stage, and details of 5- and 10-year follow-up to assess survival. Forty-nine patients age 40 years or younger received treatment for colorectal cancer at St. Mark's Hospital from 1982 to 1992. The overall 5- and 10-year survival was 58 per cent and 46 per cent respectively. The study provides more evidence to support the fact that young patients with colorectal cancer seem to present with more advanced disease. Despite this, the overall 5-year relative survival rate is comparable if not better than other studies, supporting recent evidence that the prognosis in this group of patients is no worse than for colorectal cancer in the population as a whole.

Diverticulitis.

Although diverticular disease is common in the Western world, few patients who develop diverticulitis require surgery. The use of appropriate broad-spectrum antibiotics in uncomplicated diverticulitis can be an effective treatment, avoiding the need for acute surgical intervention. In the event of surgery the choice of procedure is dictated by the degree of contamination and the expertise of the operating surgeon. This chapter will outline the modern management of diverticulitis, from steps in diagnosis to different surgical options in each clinical scenario, thus aiding clinicians on a practical level.

Short-term outcome of fertility-sparing laparoscopic excision of deeply infiltrating pelvic endometriosis performed in a tertiary referral center.

OBJECTIVE: To examine the short-term surgical outcomes in women undergoing fertility-sparing laparoscopic excision of deeply infiltrating pelvic endometriosis. DESIGN: Retrospective cohort study. SETTING: Tertiary referral center for treatment of endometriosis, a university teaching hospital, London, United Kingdom. PATIENT(S): A total of 177 women who underwent fertility-sparing laparoscopic excision of deeply infiltrating endometriosis between January 1, 2006, and December 31, 2007. INTERVENTION(S): Eligible women were identified from the surgeons' database, and their medical notes were reviewed. Data from preoperative assessment, surgery, and postoperative outcomes were analyzed. MAIN OUTCOME MEASURE(S): Complication rate. RESULT(S): One hundred seventy-seven women underwent fertility-sparing laparoscopic excision of deeply infiltrating endometriosis including excision of uterosacral ligaments (43, 24.3%), excision of rectovaginal septum (56, 31.6%), rectal shave (56, 31.6%), disk excision (7, 4%) or bowel resection (15, 8.5%). The median operative time was 95 minutes with a range of 30 to 270 minutes (interquartile range 75-120 minutes). Overall, complications developed in 18 women (10.2%). In 12 (6.8%) of these only uncomplicated pyrexia developed whereas significant intraoperative and/or postoperative complications developed in the remaining 6 (3.4%). Women spent a median of 2 days recovering in hospital (range 1-7, interquartile range 2-3 days). CONCLUSION(S): Fertility-sparing laparoscopic excision of deeply infiltrating endometriosis appears to be safe with a low short-term complication rate.

Prediction of postoperative mortality in elderly patients with colorectal cancer.

PURPOSE: This study was designed to develop a model for predicting postoperative mortality in elderly patients undergoing surgery for colorectal cancer. METHODS: This multicenter study was conducted by using routinely collected clinical data, assessing patients older than aged 80 years, with 30-day operative mortality as the primary end point. Data were collected from The Association of Coloproctology of Great Britain and Ireland database, encompassing 8,077 newly diagnosed colorectal cancer patients undergoing resectional surgery in 79 hospitals between April 2000 to March 2002, The Association of Coloproctology Malignant Bowel Obstruction Study, encompassing 1,046 patients with malignant bowel obstruction in 148 hospitals, between April 1998 to March 1999, and The Wales-Trent audit, encompassing 3,522 newly diagnosed colorectal cancer patients, between July 1992 to June 1993. A multilevel logistic regression model was developed to adjust for case-mix and to accommodate the variability of outcomes between the three study populations. The model was internally validated using a Bayesian resampling technique and tested using measures of discrimination, calibration, and subgroup analysis. RESULTS: A total of 2,533 patients satisfied the inclusion criteria, with a 30-day mortality of 15.6 percent. Multivariate analysis identified the following independent risk factors: age (odds ratio for 85-90, 90-95, >95 vs. 80-85 = 1.1, 1.8, 2.9), American Society of Anesthesiology grade (odds ratio for Grade III, IV vs. I-II = 2.7, 6.1), operative urgency (odds ratio for emergency vs. elective = 1.9), no cancer excision vs. resection (odds ratio = 1.2), and metastatic disease (odds ratio for metastases vs. no metastases = 1.9). The model offered adequate discrimination (area under receiver operator curve = 0.732) and excellent agreement between observed and predicted outcomes during eight colorectal procedures (P = 0.885). CONCLUSIONS: The elderly colorectal cancer model can accurately estimate 30-day mortality in patients older than aged 80 years undergoing surgery for colorectal cancer. Because the mortality can be considerable, this may have important implications when determining management for this group of patients.

Value of hydrogen peroxide enhancement of three-dimensional endoanal ultrasound in fistula-in-ano.

PURPOSE: The aim of this prospective study was to compare the accuracy of three-dimensional endoanal ultrasound with that of hydrogen peroxide enhanced three-dimensional endoanal ultrasound in diagnosing recurrent or complex fistula-in-ano. METHODS: Three-dimensional endoanal ultrasound reconstructions were performed before and after hydrogen peroxide enhancement in 19 patients with suspected recurrent or complex fistula-in-ano. Two experienced observers derived a consensus fistula classification after a blinded random review of the data sets. The accuracy of three-dimensional endoanal ultrasound and that of hydrogen peroxide-enhanced three-dimensional endoanal ultrasound were compared with a reference standard derived from surgical findings and magnetic resonance imaging and modified by outcome over a median follow-up of 13 months. RESULTS: Patients had previously undergone a median of three fistula operations. Four had Crohn's disease. There were 21 internal openings and primary tracks in 19 patients: 1 superficial, 1 intersphincteric, 18 transsphincteric, and 1 extrasphincteric. Fourteen patients had 19 secondary tracks. Both techniques detected fistula tracks in 19 of 21 (90 percent) patients. There was no significant difference between three-dimensional endoanal ultrasound and hydrogen peroxide-enhanced three-dimensional endoanal ultrasound in classifying internal openings (19/21 (90 percent) vs. 18/21 (86 percent)), primary tracks (17/21 (81 percent) vs. 15/21 (71 percent)), or secondary tracks (13/19 (68 percent) vs. 12/19 (63 percent)). Where three-dimensional endoanal ultrasound correctly detected an internal opening, gas from hydrogen peroxide enhancement was present in 8 of 18 (44 percent) studies. Similarly, gas made primary tracks more conspicuous in 6 of 19 (32 percent) and secondary tracks in 6 of 13 (46 percent) of those detected. CONCLUSIONS: In recurrent or complex fistula-in-ano, endoanal ultrasound proved more accurate for detecting primary tracks and internal openings than for detecting extensions. Hydrogen peroxide improved conspicuity of some tracks and internal openings and so may be helpful in difficult cases, although no overall diagnostic benefit was demonstrated.

Pilot study: fibrin sealant in anal fistula model.

PURPOSE: The aim of this study was to investigate the failure of fibrin sealant treatment for fistula-in-ano in an experimental porcine model and to determine histologic changes associated with the sealant and setons. METHODS: Three surgically created fistulas were treated by seton drainage in each of eight male pigs. After 26 days, magnetic resonance imaging was performed and setons were removed. Two pigs were killed as controls for stereologic histologic fistula track assessment. In six, fistulas were curetted, and in four the fistulas were treated with fibrin sealant. In these four sealant and two seton pigs, magnetic resonance imaging was repeated a median of 47.5 days after fistula formation. The pigs were killed and stereologic histologic fistula track examination was performed to determine granulation tissue and fistula lumen volumes. These values were compared among control, seton, and sealant groups over time, and related to fistula volumes derived from magnetic resonance imaging. RESULTS: Sealant was not visible microscopically within tracks, although some sections revealed a foreign body-type reaction. On stereologic assessment, granulation tissue volumes were smaller in sealant and seton groups than in controls (median, 88 vs. 187 vs. 453 mm3, respectively; P = 0.002) and decreased over time (median, 408 and 152 mm3 (Day 42) vs. 88 and 75 (Day 53), respectively; P = 0.002). Fistula lumen (P < 0.001), and granulation tissue combined with fistula lumen volumes (P = 0.002) were similarly smaller. Magnetic resonance imaging of fistula intensity was less in the sealant group than in the seton group and controls (mean, 777 vs. 978 vs. 1214 units/mm2, P = 0.003). Magnetic resonance imaging fistula volumes were least in sealant and seton groups vs. controls (P = 0.024), decreasing significantly in the sealant group over time (P = 0.018). No direct relationship was found between imaging and histologic volumes. CONCLUSIONS: In an experimental porcine model of anal fistula, granulation tissue was still present, albeit diminished, following track curettage combined with seton or sealant therapy, and was minimal in the sealant group, confirming some benefit from this procedure. Eradication of all longstanding granulation tissue may ensure complete success of fibrin sealant therapy.

Experimental model of fistula-in-ano.

PURPOSE: This study was designed to create and evaluate an experimental porcine model of fistula-in-ano. METHODS: Initial cadaveric dissection enabled refinement of the technique for fistula formation and histoanatomical study of the porcine anal canal. Subsequently, three surgically created fistulas were treated by seton drainage in each of eight male pigs (weight, 38-41 kg). After 26 days, magnetic resonance imaging at 1.5 Tesla was performed and setons removed under general anesthesia, enabling clinical and microbiologic track assessment. Two pigs were killed for histologic fistula track assessment. RESULTS: Histoanatomical assessment noted a rudimentary internal anal sphincter, together with structures resembling anal glands. Artificial fistulas persisted during seton drainage and were more often associated with fecal than skin-derived organisms compared with both perineal and anal canal swabs (P = 0.002). All six fistulas assessed histologically had a lumen, and abundant surrounding granulation tissue similar to that seen in human fistula-in-ano. Epithelialization was not evident in any track. Fistulas were visualized as high signal tracks using magnetic resonance imaging. CONCLUSIONS: Porcine anal anatomy resembles that of humans, and an experimental model proved suitable when assessed by magnetic resonance imaging, microbiology, and histologically, which demonstrated abundant granulation tissue. This model could be further used to investigate fistula treatments.

Clinical examination, endosonography, and MR imaging in preoperative assessment of fistula in ano: comparison with outcome-based reference standard.

PURPOSE: To prospectively evaluate the relative accuracy of digital examination, anal endosonography, and magnetic resonance (MR) imaging for preoperative assessment of fistula in ano by comparison to an outcome-derived reference standard. MATERIALS AND METHODS: Ethical committee approval and informed consent were obtained. A total of 104 patients who were suspected of having fistula in ano underwent preoperative digital examination, 10-MHz anal endosonography, and body-coil MR imaging. Fistula classification was determined with each modality, with reviewers blinded to findings of other assessments. For fistula classification, an outcome-derived reference standard was based on a combination of subsequent surgical and MR imaging findings and clinical outcome after surgery. The proportion of patients correctly classified and agreement between the preoperative assessment and reference standard were determined with trend tests and kappa statistics, respectively. RESULTS: There was a significant linear trend (P < .001) in the proportion of fistula tracks (n = 108) correctly classified with each modality, as follows: clinical examination, 66 (61%) patients; endosonography, 87 (81%) patients; MR imaging, 97 (90%) patients. Similar trends were found for the correct anatomic classification of abscesses (P < .001), horseshoe extensions (P = .003), and internal openings (n = 99, P < .001); endosonography was used to correctly identify the internal opening in 90 (91%) patients versus 96 (97%) patients with MR imaging. Agreement between the outcome-derived reference standard and digital examination, endosonography, and MR imaging for classification of the primary track was fair (kappa = 0.38), good (kappa = 0.68), and very good (kappa = 0.84), respectively, and fair (kappa = 0.29), good (kappa = 0.64), and very good (kappa = 0.88), respectively, for classification of abscesses and horseshoe extensions combined. CONCLUSION: Endosonography with a high-frequency transducer is superior to digital examination for the preoperative classification of fistula in ano. While MR imaging remains superior in all respects, endosonography is a viable alternative for identification of the internal opening.

Effect of MRI on clinical outcome of recurrent fistula-in-ano.

Recurrent fistula-in-ano is usually due to sepsis missed at surgery, which can be identified by MRI. We aimed to establish the therapeutic effect of MRI in patients with fistula-in-ano. We did MRI in 71 patients with recurrent fistula, with further surgery done at the discretion of the surgeon. Surgery and MRI agreed in 40 patients, five (13%) of whom had further recurrence, compared with 16 (52%) of 31 in whom surgery and MRI disagreed (p=0.0005). Further recurrence in all 16 was at the site predicted by MRI. For surgeons who always acted on MRI, further recurrences arose in four of 25 (16%) operations versus eight of 14 (57%) operations for those who ignored imaging (p=0.008). Surgery guided by MRI reduces further recurrence of fistula-in-ano by 75% and should be done in all patients with recurrent fistula.