Hello Raheel and welcome to HCM
Surgery is choice of treatment in Fistula in ano specially in high fistula as in your case. Firstly it is treated by antibiotic and other supportive method, if it does't resolve by it own than surgery has to be performed.
is done in which incision is made from fistula track to anal canal
and healing of the tissue is from inside to out. Other method to treat fistula is Ksarsutra Therapy in Ayurveda. Consult a Ksarsutra specialist for detail of it. But it is a long healing procedure.
Now regarding prognosis in both the procedure the reported rate of recurrence is 0-18%.
Hope you got all your answers.