ITS A DICTUM THAT WHATEVER THE NUMBER OF EXTERNAL OPENINGS OF ANAL FISTULAS, THE INTERNAL OPENING IS SINGLE. HOWEVER, THIS CASE PRESENTS A RARE FINDINGS THAT 3 EXTERNAL OPENING HAD 3 DIFFERENT INTERNAL OPENINGS.

An intersphincteric fistula tracks through the distal internal sphincter and intersphincteric space to an external opening near the anal verge.
The aim of surgical treatment of perianal fistulas is to treat the patient's symptoms, with low recurrence rates and risk of incontinence. In recent years there have been developments regarding the classification and diagnosis of perianal fistulas.
. As a result of developments in fistula surgery it is now more practical to classify perianal fistulas as low or high fistulas, as this has implications for the further treatment. Low perianal fistulas are defined as fistulas of which the fistula tract is located in the lower third of the external anal sphincter.

MRI is the most appropriate diagnostic tool. In the hands of an experienced operator anal endosonography is a suitable, less expensive and readily-available alternative.

The first group contains ‘low’ or ‘simple’ fistulae, which are intersphincteric or trans-sphincteric fistulae involving only the lower one-third of the sphincter complex. Alternatively, they may not involve any muscle. The second group contains ‘high’ or ‘complex’ fistulae. These are the remainder of intersphincteric and trans-sphincteric fistulae, and also suprasphincteric and extrasphincteric fistulae. However, not all authors use the same classification, which can cause problems when analyzing the literature.

Rectal examination yields valuable information such as the presence of scarring from previous surgery, the state of the sphincters, induration at the site of an internal opening or an associated mass. A low rectal adenocarcinoma or anal carcinoma can produce similar symptoms to those of a fistula, and this must always be excluded before planning any treatment for a fistula.
If there is no clinical suspicion of Crohn’s disease during EUA, and the external opening is near the anal canal and the fistula is of short length, then it is likely that the fistula is simple. If this is the case, it can be laid open at the time of the EUA . If the fistula involves more than one-third of the depth of muscle in the external anal sphincter, a seton can be placed.
Fistulotomy
Low perianal fistulae are treated with EUA and fistulotomy, and laying open the fistula. Usually, this involves the division of part of the sphincter muscle. There is much debate as to how much sphincter muscle can safely be divided, and the problem in interpreting the literature is the lack of a clear definition of ‘low’ or ‘complex’ fistulae. In their definition, some authors include as ‘low’ fistulae, those that do not traverse any muscle at all. Clearly, there will be no incontinence if no muscle is divided.
Many authors have suggested that good results can be obtained by performing a fistulotomy on ‘low’ fistulae that traverse only one-third or less of the external sphincter muscle . On the other hand, complex fistulae usually require one of the approaches described below. Biopsy is also performed in cases of suspected Crohn’s disease. Marsupialization after fistulotomy reduces bleeding a

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