Fistula in ano: anatomoclinical aspects, surgical therapy and results in 844 patients

Several new therapies, including advancement flaps and fibrin glue, have been proposed for fistula in ano, with conflicting results. Most colorectal surgeons continue to use classic methods, e.g. fistulotomy, fistulectomy, a combined method, loose or cutting seton, and rubber loop. The aim of the present study is to report the outcome of our patients, operated on by such methods.

We retrospectively reviewed the clinical records of 844 patients treated for anal fistula over a 30-year period, and assessed fistula morphology, surgical procedure and healing period. For patients treated 2 or more years prior to this study, we evaluated rates of persistent fistula and relapse, as well as prevalence of incontinence and patient satisfaction.

The majority of patients had trans-sphincteric fistulae (58.3%). We observed 274 secondary extensions (32.5%); these were common in all fistula types except for intrasphincteric fistulae. Most patients were treated by fistulotomy alone (594 patients, 70.4%) or by the combined fistulectomy-fistulotomy method (237 patients, 28.1%), with or without loose seton. All patients with trans-, supra- and extrasphincteric fistulae were re-examined in the operations theatre. Follow-up data were available for 652 (87%) of 751 patients at least two years after surgery. The anal fistula persisted in 3.2% and recurred in 2.1% of cases. A second procedure lowered the initial rate of unsuccessful operations from 5.3% to 2.5%. Continence disorders were reported in 6.9% of patients: 4.0% complained of incontinence to gas, 2.6% to liquid and 0.3% to solid feces.

Fistulotomy and fistulectomy with loose seton supported by preoperative anal manometry and postoperative evaluation under anaesthesia are followed by good clinical and functional results.