[Quality indicators in the treatment of anal fistulas]

Anal fistulas are a common anorectal disease and are frequently associated with a perianal abscess. The etiology is based on a cryptoglandular infection in the intersphincteric space. Surgery remains the only definitive therapy. The primary goal of definitive fistula surgery is healing; however, success of fistula surgery is influenced by a variety of factors including the surgeon's experience, type of fistula, involvement of sphincter muscles, type of surgical procedure and patient-related factors. For the surgical treatment of a complex anal fistula, a variety of operative procedures have been described including fistulectomy with sphincterotomy, different flap procedures (e.g. mucosal flap and advancement flap) and finally so-called sphincter-preserving techniques, such as LIFT (ligation of intersphincteric fistula tract), VAAFT (video-assisted anal fistula treatment), the use of plugs of collagen or fibrin glue sealants as well as laser procedures or the clip. In the search for suitable quality indicators in anal fistula surgery there is a conflict between healing and preservation of continence. If potential quality indicators are identified the principles of anal fistula surgery must be adhered to and the appropriate selection of patients and procedures is of crucial importance to achieve high healing rates without compromising continence or inducing surgical revision due to abscesses or recurrence. Based on the available literature and guidelines, in the assessment of quality indicators considerable differences exist with respect to patient selection, etiology of anal fistulas and length of follow-up. Heterogeneity of treatment protocols lead to difficulties in a definitive assessment of which surgical treatment is the best option for complex anal fistulas.