I wil go with a preoperative MRI, to better define the fistula tract. Advancement flap of the mucosa to close the internal fistular orifice. Curettage of all the entire fistula tract and fibrin glue obstruction.
rule out crohns. In the case of idiopathic one, cone like fistulectomy then mucosal advancement flap and /or biologic plug placement. In the case of CD fistula, cone like fistulectomy then consider biologics
Video Assisted Anal Fistula Treatment (VAAFT) is a good option in recurrent high FIA. It allows visualization of the main and side tracks and possibly the internal opening as well. It can be both diagnostic and therapeutic.
The track definition a this time is usless, you already have a complex fístula and need to close it. If you already ruled out an IBD disease, try a muco-muscular flap with a 3 months period colostomy.