Hi, Welcome to health care magic, There are few different kinds of surgeries done in anal fistula spending upon the type of. Out of all these what is the preference your Surgeon can not be understood by me unless you tell me what your Surgeon told or explained. This will give me some idea to tell you the details. The first stage is to colostomy to bypass the anus of the feces full of bacteria. In second stage then they would Excise the whole fistula tract and restitch the internal sphincter. In the third stage, Once this anal wound is healed colostomy is closed. -If the anal fistula is of low type which seems to be in your case,this is a single stage surgery, where either the tracts is laid open to allow to heal. The dangers: The biggest danger is incontinence- occurs only if the internal sphincter in inadvertently cut through and through. as a single cut, that no surgeon with the knowledge would do. It is imperative that the biopsy is done before or after surgery as there is a chance to know if the primary reason is like tuberculosis or Crohns. There are chances of recurrence which could be the reason of your recurring abscess and fistula. Regards,