Management of Fistula-in-Ano—The Current Evidence

Successful treatment for fistula in ano has eluded most surgeons. To choose the right surgery has been made more difficult, with new surgeries being added in the last decade. This article discusses the various accepted surgeries for fistula in ano - their pros & cons, & attempts to provide the status of the various procedures as it stands today.     

MR Imaging of Fistula in Ano: Indications and Contribution to Surgical Assessment

Background : Magnetic Resonance Imaging (MRI) is the imaging modality of choice for fistula in ano. The purpose of this study was to analyse the use of MRI, and to assess its contribution towards the assessment of this sometimes difficult condition.

Methods : A retrospective analysis of all patients with fistula in ano between January 2003 and December 2007 was performed, focussing on those who had MRI assessment. The primary pathology, indication for MRI and the contribution of this investigation to assessment of fistula in ano were analysed.

Results : MRI was performed in 40 patients. The primary pathologies included: perianal sepsis in 20 (50%), Crohn’s disease in 11 (27.5%), primary fistula in ano in 6 (15%) and others in 3 (7.5%) patients. Indications for MRI were to assess the fistula anatomy in 17 (42.5%), to assess a clinically suspected fistula in 12 (30%), to assess a complex fistula found at Examination Under Anaesthesia (EUA) in 6 (15%) and to exclude a fistula in 5 (12.5%). MRI was considered helpful in 34 (85%) of all cases. MRI established the fistula anatomy and guided further surgery in 47.1%, correlated with EUA findings in 38.2% and excluded a suspected fistula in 14.7% of these.

Conclusions : This study further supports the benefit of using MRI to assess fistula in ano. When used in selected patients, it was of benefit in 85% of cases, by establishing fistula anatomy and guiding further surgery, correlating EUA findings or excluding a clinically suspected fistula.     

Implantation of Rectal Cancer Cells in a Fistula in Ano: Report of a Case

We report a case of implantation of tumor cells within a fistula in ano. A 36-year-old man with a 16-year history of an anal fistula underwent an operation for rectal carcinoma. Three weeks later, the anal fistula was resected. A histological examination of the specimen showed atypical cells; moreover, rectal carcinoma had proliferated in the granulation tissue lying underneath the intact squamous epithelium. Because there was no continuity to the rectal carcinoma or the anal glands, we diagnosed implantation of rectal cancer cells in a fistula in ano. Received: February 19, 2001 / Accepted: July 17, 2001     

Anal endosonography in the evaluation of perianal sepsis and fistula in ano

Anal endosonography has been performed in 22 patients with fistula in ano and perianal sepsis and compared with the operative findings. Using a special hard cone attachment to a radial 7 MHz probe the examination was well tolerated, rapid and generally accurate, detecting two unsuspected foreign bodies and all seven complicated fistula in ano preoperatively.     

Long-term outcome following loose-seton technique for external sphincter preservation in complex anal fistula

BACKGROUND: This study determined the long-term outcome after use of the loose-seton technique (LST) to eradicate complex fistula in ano. METHODS: Twenty patients whose complex fistula in ano was treated by the LST a minimum of 10 years previously were assessed by case-note review, supplemented where necessary by mailed and telephone interview. RESULTS: Eighteen patients had a trans-sphincteric and two a suprasphincteric fistula. There were seven supralevator and 12 ischiorectal secondary extensions. At short-term follow-up, a median of 6 months following seton removal, perianal sepsis had been eradicated in 13 of 20 patients. However, the long-term success rate of the LST was lower than that noted in the short term (four versus 13 of 20). Sixteen patients had persisting or recurrent sepsis, necessitating further surgery in 13. In the long term, external sphincter division was necessary to control sepsis in seven of the 20 patients compared with three of 20 patients at short-term follow-up. The rate of relapse in those with Crohn's disease and cryptoglandular fistula in ano was similar (five of six versus 11 of 14; P = 1.000). The fistula recurred in seven, 11 and 15 patients at 6, 15 and 60 months respectively after seton removal. CONCLUSION: The success rate of the LST for complex fistula in ano falls over time. Counselling before seton removal should emphasize that, although most patients do not require sphincter division and some are cured by this technique, many patients develop further sepsis that usually requires surgery.     

The efficacy of anal fistula plug in fistula‐in‐ano: a systematic review

Aims To assess the efficacy of anal fistula plug (AFP) procedure for the treatment of fistula‐in‐ano especially the complex fistulas. Method The database of PUBMED, MEDLINE, SCOPUS, EMBASE and COCHRANE LIBRARY for the period 1995–2009 was searched. A systematic analysis was carried to evaluate the success rate of AFP procedure in fistula‐in‐ano. Results A total of 25 studies were extracted and 12 (n = 317) were finally included in the systematic review. The follow‐up period ranged from 3.5 to 12 months. The AFP procedure had a success rate (patient cure rate) ranging from 24% to 92%. In complex fistula‐in‐ano in prospective studies (8/12 studies), the success rate was 35–87%. The success rate in patients with Crohn’s disease was 29–86%. The success rate in the patients with single tracts was 44–93% and in patients with multiple tracts, success ranged from 20% to 71%. The abscess formation/sepsis rate was 4–29% (11/108) and the plug extrusion rate was 4–41% (42/232–19%). Conclusion Anal fistula plug procedure has a success rate ranging from 24% to 92% in different studies. In prospective studies of complex fistula‐in‐ano, there was a moderate success rate of 35–87%. As AFP is associated with low morbidity and sepsis, it appears to be a safe procedure. Further randomized controlled trials studying objective parameters of fistula healing are needed to substantiate these findings.     

Anal fistula and pilonidal sinus disease coexisting simultaneously: An audit in a cohort of 1284 patients

Fistula‐in‐ano and pilonidal disease are not known to occur together. In a retrospective study, all patients having fistula‐pilonidal disease coexisting simultaneously were included. Out of 1284 patients, 933 were operated (fistula‐in‐ano, 849; pilonidal disease, 77; and coexisting fistula‐pilonidal, 7). A total of 351 patients did not undergo any surgery (two patients had coexisting fistula‐pilonidal). Thus, a total of nine patients having coexisting fistula‐pilonidal sinus were included in the study (mean age 35.8 ± 19.9 years, M/F 7/2). pIn 6/9 patients, the pilonidal tract was communicating with fistula‐in‐ano, and in 3/9 patients, they were not communicating/connected. The connection could be established preoperatively with the help of MRI. In all patients with communicating fistula‐pilonidal sinus (n=6), the fistula was posterior. 6/9 patients had recurrent fistula and all (9/9) had multiple tracts. The fistula was high and complex in 8/9 patients (grade IV‐7, grade V‐1). 4/9 patients tested positive for tuberculosis while one patient was suffering from hidradenitis suppurativa. The latter improved on medical treatment. One patient did not agree for surgery and seven were operated. The disease healed in four patients, the disease did not heal in one patient, and two patients were in the convalescent stage. Anal fistula and pilonidal disease can coexist in a same patient and can even be connected. Such diseases are more complex and have a higher incidence of associated diseases like tuberculosis. Magnetic resonance imaging plays a pivotal role in diagnosis. If the connection is missed, the disease treatment becomes difficult.     

Magnetic resonance imaging for primary fistula in ano

BACKGROUND: This was a prospective study designed to determine the therapeutic impact of magnetic resonance imaging (MRI) in primary fistula in ano, and to assess its effect on outcome. METHODS: Thirty patients with suspected primary fistula in ano underwent preoperative MRI, and the findings were revealed during surgery following examination under anaesthesia (EUA). Any effect on operative approach was noted. Outcome was assessed at a median of 12 months. RESULTS: Two patients had sinuses, one had no sepsis and 27 had fistulas: five superficial, seven intersphincteric, 14 trans-sphincteric and one suprasphincteric. MRI and EUA agreed in 15 patients and MRI findings altered the surgical approach in a further three (10 per cent); two of the latter patients were believed to have a sinus at EUA, which MRI correctly identified as a fistula, allowing definitive treatment. The therapeutic impact of MRI was therefore 10 per cent. Persisting disagreement between MRI and EUA in 12 patients mostly related to minor discrepancies in classification. Only one patient required further unplanned surgery, which was for skin-bridging rather than any new sepsis. CONCLUSION: In experienced hands, MRI has a therapeutic impact of 10 per cent for primary fistula in ano, precipitating surgery that is likely to reduce recurrence in a small, but important, proportion of patients.     

Fistulotomy or seton in anal fistula: a decisional algorithm

Fistula in ano is a common proctological disease. Several authors stated that internal and external anal sphincters preservation is in the interest of continence maintenance. The aim of the present study is to report our experience using a decisional algorithm on sphincter saving procedures that achieved us to obtain good results with low rate of complications. From 2008 to 2011, 206 patients underwent surgical treatment for anal fistula; 28 patients underwent perianal abscess drainage plus seton placement of trans-sphincteric or supra-sphincteric fistula (13.6 %), 41 patients underwent fistulotomy for submucosal or low inter-sphincteric or low trans-sphincteric anal fistula (19.9 %) and 137 patients underwent partial fistulectomy or partial fistulotomy (from cutaneous plan to external sphincter muscle plan) and cutting seton placement without internal sphincterotomy for trans-sphincteric anal fistula (66.50 %). Healing rates have been of 100 % and healing times ranged from 1 to 6 months in 97 % of patients treated by setons. Transient fecal soiling was reported by 19 patients affected by trans-sphincteric fistula (11.5 %) for 4–6 months and then disappeared or evolved in a milder form of flatus occasional incontinence. No major incontinence has been reported also after fistulotomy. Fistula recurred in five cases of trans-sphincteric fistula treated by seton placement (one with abscess) (1/28) (3.5 %) and four with trans-sphincteric fistula (4/137) (3 %). Our algorithm permitted us to reduce to 20 % sphincter cutting procedures without reporting postoperative major anal incontinence; it seems to open an interesting way in the treatment of anal fistula.     

Lambeau d’avancement rectal

Rectal advancement flap is a surgical procedure for treating Crohn’s disease related or cryptogenetic fistula in ano and rectovaginal fistula. Success rates range from 50 to 90% depending on the etiology of the fistula. Postoperative morbidity is low, and this endoanal procedure is often performed as a first surgical step for complex or recurrent fistula.     

A systematic review of new treatments for cryptoglandular fistula in ano

Aim

In 2007 the ACPGBI published a position statement on the management of cryptoglandular fistula in ano. Over the last seven years a number of new treatments have been developed and the aim of this systematic review was to assess their effectiveness.

Anal Lesion resulting from Implantation of Viable Tumour Cells in a Pre-existing Anal Fistula. A Case Report

Colorectal cancer exfoliates cancer cells into the lumen of the bowel, and possibly, raw bowel mucosa should provide a good medium for the exfoliated cancer cells. We report an extremely rare case of a sigmoid carcinoma metas-tasizing to a low fistula in ano. The patient was operated on for a fistula in ano. Biopsy demonstrated a moderate differentiated adenocarcinoma. Thereafter, sigmoidoscopy revealed an intraluminal mass at the sigmoid colon. The patient subsequently underwent abdominoperineal resection of the sigmoid colon and rectum. In conclusion, surgeons should be aware of the possibility of cancer spread incidence, distally beyond the initial site by exfoliated cancer cells into the lumen of the bowel.     

Anal lesion resulting from implantation of viable tumour cells in a pre-existing anal fistula. A case report

Colorectal cancer exfoliates cancer cells into the lumen of the bowel, and possibly, raw bowel mucosa should provide a good medium for the exfoliated cancer cells. We report an extremely rare case of a sigmoid carcinoma metastasizing to a low fistula in ano. The patient was operated on for a fistula in ano. Biopsy demonstrated a moderate differentiated adenocarcinoma. Thereafter, sigmoidoscopy revealed an intraluminal mass at the sigmoid colon. The patient subsequently underwent abdominoperineal resection of the sigmoid colon and rectum. In conclusion, surgeons should be aware of the possibility of cancer spread incidence, distally beyond the initial site by exfoliated cancer cells into the lumen of the bowel.     

Anography: a technique for determining the location of the internal opening in perianal fistula

Aim Anography is a radiological investigation for fistula‐in‐ano that identifies the primary fistula track through the internal opening. The efficacy of anography as a radiological method of identifying the location of the internal opening was investigated. Method A retrospective study of 50 patients with a clinical diagnosis of fistula‐in‐ano of criptoglandular aetiology was performed. During anography, the location of the internal opening was recorded with respect to the quadrant of anal canal and distance from the anal verge. These data were compared with the findings during examination under anaesthesia (EUA), which was used as the gold standard for the identification of the internal opening. Results The sensitivity of anography for identifying a patent internal opening was 91% and specificity 100%. There was complete agreement between anography reports and findings at EUA regarding the quadrant of anal canal in which the internal opening was located. In more than 90% of patients, the internal opening was found at EUA within 1 cm from the site described on anography. Conclusion Anography is an accurate test for predicting the exact quadrant of the anal canal in which the internal opening is located, as well as the distance of the internal opening from the anal verge. This inexpensive and simple radiological investigation should be the test of first choice in the evaluation of patients with fistula‐in‐ano when difficulty is anticipated in identifying the internal opening.     

The value of routine histopathological analysis in patients with fistula in‐ano

Objective To determine the positive yield of routine histopathology in patients undergoing surgery for fistula in‐ano. Method Histopathology reports of all the patients who underwent surgery for fistulae‐in‐ano over a period of 36 months were reviewed. Results Analysis included 84 patients of which 73 (87%) were male subjects. The mean age was 39.4 years (range 11–68). Forty‐one (49%) had recurrent fistulae. Granulomatous diseases such as Crohn’s disease and tuberculosis (TB) were suspected in six patients. However, of the six patients, confirmation of the disease status was obtained only in three patients: stains for acid‐fast bacilli confirmed TB in two (2.4%) patients and colonoscopy and biopsy confirmed Crohn’s disease in one (1.2%) patient. All three patients had recurrent fistulae. Conclusion As the positive yield of routine histopathology is minimal, we do not recommend routine histopathology for fistula in‐ano, except for those presenting with recurrent fistulae and those with clinical suspicion of an underlying disease such as TB, HIV or Crohn’s disease.     

La technique LIFT de ligature/section intersphinctérienne du trajet de fistule dans la prise en charge des fistules trans-sphinctériennes hautes

Ligation of the intersphincteric fistula tract is a new treatment option for transsphincteric fistula in ano. The technique is described step by step and the results reported in the literature are discussed. This innovative approach remains to be evaluated and may offer promising results if confirmed and raise new perspectives of healing for those fistulae.     

Comparison of Preoperative Endoanal Ultrasonography with Intraoperative Findings for Fistula In Ano

Background  

Fistula in ano is a common benign anal condition seen in surgical practice. If fistula anatomy is incorrectly delineated or an occult abscess is missed, there is a risk of incomplete healing, recurrence of the fistula, or even iatrogenic sphincter injury from surgery resulting in anal incontinence. Therefore, an imaging modality ideally would provide accurate information that can be used to delineate the tract(s) prior to surgery. The aim of this study was to determine the accuracy of endoanal ultrasonography (EAUS) during the preoperative assessment of anal fistula tracts in respect to the type of the fistula, horseshoeing of the tract, and localized collections.     

Video-Assisted Anal Fistula Treatment

Background and Objectives:

Fistula in ano is a common disease seen in the surgical outpatient department. Many procedures are advocated for the treatment of fistula in ano. However, none of the procedures is considered the gold standard. The latest addition to the list of treatment options is video-assisted anal fistula treatment (VAAFT). It is a minimally invasive, sphincter-saving procedure with low morbidity. The aim of our study was to compare the results with a premier study done previously.

Methods:

The procedure involves diagnostic fistuloscopy and visualization of the internal opening, followed by fulguration of the fistulous tract and closure of the internal opening with a stapling device or suture ligation. The video equipment (Karl Storz, Tuttlingen, Germany) was connected to an illuminating source.

Results:

The study was conducted from July 2010 to March 2014. Eighty-two patients with fistula in ano were operated on with VAAFT and were followed up according to the study protocol. The recurrence rate was 15.85%, with recurrences developing in 13 cases. Postoperative pain and discomfort were minimal.

Conclusion:

VAAFT is a minimally invasive procedure performed under direct visualization. It enables visualization of the internal opening and secondary branches or abscess cavities. It is a sphincter-saving procedure and offers many advantages to patients. Our initial results with the procedure are quite encouraging.     

Accuracy of hydrogen peroxide-enhanced ultrasound in the identification of internal openings of anal fistulas

Objective This prospective study was designed to assess the accuracy of hydrogen peroxide‐enhanced ultrasound in the identification of internal openings of anal fistulas, with surgical findings as the golden standard. Patients and methods A total of 143 consecutive patients (102 men; mean age, 45 years) with fistula‐in‐ano were assessed by hydrogen peroxide‐enhanced ultrasound before surgery involving one radiologist. Ultrasound was performed using a B & K Diagnostic Ultrasound System^? with a 10‐MHz rotating endoprobe. Hydrogen peroxide (3%) was infused into the fistula. All operations were perfomed by the same surgeon who was unaware of results of anal endosonography. Results In 128 (89.5%) patients, an internal opening was identified at surgery. Correct identification of an internal opening endosonographically was recorded in 80 (62.5%) patients. The internal opening was correctly identified by ultrasound in 32% (8/25) of patients with intersphincteric fistulas, in 77% (70/91) with transsphincteric fistulas, and in 17% (2/12) with suprasphincteric fistulas. Conclusion The accuracy of hydrogen peroxide‐enhanced anal endosonography for the identification of internal openings was still insufficient to justify pre‐operative endosonography as a diagnostic method for routine use in patients with fistula‐in‐ano.     

Difficult fistulae

Fistula in ano is a common disorder. The goals of treatment are to cure the fistula with minimal loss of sphincter function and with minimal healing time. Fortunately about 90% of fistulae are simple and obey Goodsall's rule. These fistulae are easily treated by the "lay-open" technique. Treatment can however become much more difficult with increasing complexity of fistula tracks, higher internal opening with major sphincter involvement, atypical and secondary tracks or at recurrence. Understanding of the anatomy and the pathogenesis of fistulae is mandatory to identify the fistula tracks and the internal opening and to tailor the treatment accordingly. Endoanal flap repairs and the use of setons are most widely accepted for the treatment of difficult fistulae but many other options exist. Underlying factors or associated diseases such as inflammatory bowel, AIDS and other sexually transmitted diseases, carcinoma, radiotherapy, hidroadenitis or other obscure infections may influence the final outcome and often demand a specific approach.