The Role of Magnetic Resonance Imaging in Pre-operative Assessment of Anorectal Fistula With Surgical Correlation

Background Anorectal fistulas are chronic inflammations of peri-anal tissues that form a connection between the perineal skin and the anal canal. Accurate preoperative evaluation of the main fistula's trajectory and pelvic tissues is essential for effective surgical treatment of anal fistulas. The inability to detect concealed lesions may result in the recurrence of fistulas and the conversion of a simple fistula into a complex fistula. Magnetic resonance imaging (MRI) imaging can detect concealed pathways and abscesses, thereby exposing the intricate connection between the fistula and anal-sphincter complex. This data serves as a roadmap for making surgical decisions, thereby reducing the likelihood of illness recurrence and complications after surgery. Aim To evaluate the role of MRI in pre-operative assessment of an anorectal fistula, compare its findings with surgical results. Materials and methods The research was conducted at the Radiology Department, Apollo Hospital, Hyderabad. It was a prospective observational study. IBM SPSS Statistics for Windows, Version 17 (released 2008; IBM Corp., Armonk, New York, United States) was utilized for data analysis. The mean and standard deviation were computed. We further applied appropriate statistical tests to determine the significance of MRI features with pre-operative findings. Results MRI accurately detects features like abscesses (sensitivity-100%, specificity-97.06%), secondary tracts of the fistula (sensitivity-93.55%, specificity-94.12%), horseshoe appearance, and supralevator extension (sensitivity-100%, specificity-97.50%, and 97.62%, respectively). Conclusion When comparing our results with intraoperative findings, MRI showed high sensitivity and specificity in detecting abscesses, secondary tracts, horseshoe appearances, and supralevator extensions. Our findings suggest that MRI can offer anatomical and pathological information for the pre-operative care and surgical planning of perianal fistulas.

Subcutaneous incision of the fistula tract and internal sphincterotomy (SIFT-IS): a novel surgical procedure for transsphincteric anal fistula

AIM

The aetiology of anal fistula has not been fully clarified. One of the causes of anal fistulas may be the markedly deep crypts that characterize the primary openings. We developed subcutaneous incision of the fistula tract and internal sphincterotomy (SIFT-IS) to eradicate these deep crypts. The aim of this study was to evaluate outcomes in patients with anal fistula treated with SIFT-IS.

METHOD

A retrospective study was performed over a 2-year period. Patients with transsphincteric anal fistula who underwent SIFT-IS were enrolled. The primary endpoint was the anal fistula healing rate at 16 weeks postoperatively. The secondary endpoints were healing time, postoperative complications and clinical continence status.

RESULTS

One hundred and fifty one patients were enrolled. Primary healing was accomplished in 129 patients (85%). There were 17 patients (11%) with a remnant fistula and five (3%) with a recurrence. The remnant fistulas healed spontaneously at more than 16 weeks postoperatively in seven patients. The median healing time was 6 (3-96) weeks. Surgical intervention was required in seven patients with a remnant fistula and four with recurrence. At the final follow-up, the wounds had healed in 148 patients (98%). No significant postoperative complications or incontinence were observed.

CONCLUSION

Subcutaneous incision of the fistula tract and internal sphincterotomy is a promising surgical option for transsphincteric anal fistulas, with a satisfactory healing rate.

High failure rates following ligation of the intersphincteric fistula tract for transsphincteric anal fistulas: are preoperative MRI measurements of the fistula tract predictive of outcome?

AIM

Treatment of transsphincteric fistulas (TSFs) with fistulotomy after an indwelling seton is tempered by risks of incontinence and litigation. Thus, ligation of the TSF tract has been popularized as an alternative option. We previously reported on 107 patients who underwent ligation of the intersphincteric fistula tract (LIFT), with a 46% failure rate. Posterior fistula was the only predictor of recurrence. The aim of the present work was to investigate whether the length, width or depth of the fistula measured on preoperative MRI was correlated with recurrence.

METHOD

Following institutional review board approval, a retrospective analysis of our prospective Complex Anal Fistula Database from 1 January 2011 to 31 August 2019 was performed. Patients with TSF who underwent preoperative MRI and LIFT were included. Fistula location was classified as anterior, posterior or lateral. MRI measurements of fistula length, width and depth (in the intersphincteric groove) were performed. The type and rate of postoperative recurrence were analysed.

RESULTS

173 patients underwent MRI for an anal fistula; of these 40 underwent LIFT and 22/40 (55%) had preoperative MRI. There was no difference in the length, width or depth of anterior (n = 9), posterior (n = 7) or lateral (n = 6) fistula tracts. The overall recurrence rate was 9/22 (41%). Posterior TSFs had the highest recurrence rate (5/7, 71%).

CONCLUSION

The mean length, width, and depth of the fistula tract, measured at the preoperative site of LIFT in the intersphincteric groove, did not correlate with recurrence regardless of fistula location.

Long-term outcomes and quality of life following ligation of the intersphincteric fistula tract for high transsphincteric fistulas

AIM

Published outcomes following ligation of the intersphincteric fistula tract (LIFT) for high transsphincteric fistulas (HTFs) are equivocal probably because most trials are small and comprise mixed patient populations. The aim of this study was to highlight the long-term efficacy of LIFT for HTFs in a large homogeneous sample and to determine the risk factors that contribute to non-healing resulting in failure and recurrence.

METHOD

A retrospective study was performed which assessed patients with HTFs treated by LIFT without prior loose setons from September 2012 to December 2017. Continence function was evaluated by the Wexner incontinence scale and anal manometry. Quality of life was assessed by using the faecal incontinence quality of life (FIQL) scale with four domains: lifestyle, coping, depression and embarrassment.

RESULTS

Seventy patients with HTFs underwent 71 LIFT procedures. The primary healing rate was 81.7% with a median follow-up duration of 16.5 (range 4.5-68) months. The healing rates of mature and immature fistulas were 83.7% and 77.3%, respectively. Two patients suffered failure with an unhealed intersphincteric wound. Recurrence occurred in 11 patients. Incontinence of flatus, present in four patients before surgery, improved postoperatively. Two patients undergoing LIFT combined with fistulotomy complained of flatus incontinence after surgery. No significant differences between preoperative and postoperative Wexner score, maximum resting pressure and maximum squeeze pressure were detected. The FIQL was improved in lifestyle, coping and depression. No risk factor for non-healing was found.

CONCLUSION

LIFT has a promising long-term outcome for HTFs, with negligible impairment on continence and improved quality of life.

Management of Complex Anal Fistulas

Complex anal fistulas require careful evaluation. Prior to any attempts at definitive repair, the anatomy must be well defined and the sepsis resolved. Several muscle-sparing approaches to anal fistula are appropriate, and are often catered to the patient based on their presentation and previous repairs. Emerging technologies show promise for fistula repair, but lack long-term data.

Gore BioA Fistula Plug in the treatment of high anal fistulas--initial results from a German multicenter-study

Background: Treatment of high anal fistulas may be associated with a high risk of continence disorders. Beside traditional procedure of flap-reconstruction the occlusion of the fistula tract using fistula-plugs offers a new sphincter-saving treatment option. In this study for the first time results from Germany are described.

Patients and method: 40 patients (30 male, 10 female, age 51±12 years) underwent closure of a high trans-sphincteric (n=28) or supra-sphincteric (n=12) fistula with Gore BioA Fistula Plug^® in three surgical departments. The surgical procedures had been performed by five colorectal surgeons. Four patients had Crohn’s disease. Preoperatively 33 patients were completely continent; seven patients complained of minor continence disorders. Treatment of the patients was performed on a intent-to-treat basis and evaluation of the results was retrospective using pooled data from each center.

Results: Postoperatively one patient developed an abscess, which had to be managed surgically. In two patients the plug had fallen out within the first two weeks postoperatively. Six months after surgery the fistula has been healed in 20 patients (50.0%). Three additional fistulas healed after 7, 9 rsp. 12 months. The overall healing-rate was 57.5% (23/40). The healing rate differs considerably between the surgeons from 0 to 75% and depends on the number of previous interventions. In patients having only drainage of the abscess success occurred in 63.6% (14/22) whereas in patients after one or more flap fistula reconstruction the healing rate decreased slightly to 50% (9/18). No patient complained about any impairment of his preoperative continence status.

Conclusion: By occlusion of high anal fistulas with a plug technique definitive healing could be achieved in nearly every second patients. Previous surgery seems to have a negative impact on success rate. We have not observed any negative impact on anal continence. From that point of view anal fistula plugs might be discussed as a treatment option for high anal fistulas, but further studies are needed to gain conclusive evidence.

Repeat transanal advancement flap repair: impact on the overall healing rate of high transsphincteric fistulas and on fecal continence

PURPOSE

Transanal advancement flap repair (TAFR) has been advocated as the treatment of choice for transsphincteric fistulas passing through the upper or middle third of the external anal sphincter. It is not clear whether previous attempts at repair adversely affect the outcome of TAFR. The purpose of the present study was to evaluate the success rate of a repeat TAFR and to assess the impact of such a second procedure on the overall healing rate of high transsphincteric fistulas and on fecal continence.

METHODS

Between January 2001 and January 2005, a consecutive series of 87 patients (62 males; median age, 49 (range, 27-73) years) underwent TAFR. Median follow-up was 15 (range, 2-50) months. Patients in whom the initial operation failed were offered two further treatment options: a second flap repair or a long-term indwelling seton drainage. Twenty-six patients (male:female ratio, 5:2; median age, 51 (range, 31-72) years) preferred a repeat repair. Continence status was evaluated before and after the procedures by using the Rockwood Faecal Incontinence Severity Index (RFISI).

RESULTS

The healing rate after the first TAFR was 67 percent. Of the 29 patients in whom the initial procedure failed, 26 underwent a repeat TAFR. The healing rate after this second procedure was 69 percent, resulting in an overall success rate of 90 percent. Both before and after the first attempt of TAFR, the median RFISI was 7 (range, 0-34). In patients who underwent a second TAFR, the median RFISI before and after this procedure was 9 (range, 0-34) and 8 (range, 0-34), respectively. None of these changes were statistically significant.

CONCLUSIONS

Repeat TAFR increases the overall healing rate of high transsphincteric fistulas from 67 percent after one attempt to 90 percent after two attempts without a deteriorating effect on fecal continence.