78 patients with transsphincteric fistula allocated into two groups group A underwent LIFT group B u nderwent fistulectomy , comparison between the outcome og both procedures

This randomized comparative clinical trial was carried out in Zagazig university hospitals, general surgery department, between March 2018 and February 2020, on 78 patients with transsphincteric anal fistula.

All patients were informed and signed a written consent for participation in this study, the study was approved by the local ethical committee of our university the sample size was calculated by the statistical unit of the local institutional review board participant selection; participant included in this study are those above 18 years old, suffering transsphincteric anal fistula diagnosed by clinical examination and magnetic resonant imaging (MRI) in doubtful cases, We excluded all patients with;

• Anorectal malignancy.
• Patient with previous radiotherapy to the region.
• Those with fistula due to specific disease as Crohn's disease.
• Patients with anal incontinence.
• Patients with perianal collections.
• Patients on cytotoxic or immunosuppressive therapy. Randomization; According to intervention,participants were randomly allocated using computer generated random numbers into two groups, group A (39 patients): Patients underwent intersphincteric ligation of fistulous track (LIFT) and group B (39 patients): Patients underwent fistulectomy.

Procedures ; All participants were subjected to full clinical examination including detailed history, formal digital rectal examination for assessment of anal sphincter integrity, identification of internal and external openings of the fistula, MRI was performed in those with doubtful clinical examination. Preoperative investigations performed according to American society of anesthesia (ASA) guidelines, all patients received 1 gm third generation cephalosporin with induction of anesthesia and continued for 24 hours postoperative, fleet enema was performed 12 hours and 2 hours before operation.

Surgical technique;

Under spinal anesthesia, participants under went digital rectal examination for identification of the internal and external openings and the fistulous track course, after identification of the external opening it was propped by 14 g cannula through which 2ml hydrogen peroxide was injected and traced through anoscope inside anal canal to identify the internal opening, after that the fistulous track was propped by malleable metal probe, the definitive procedure was then performed according to patient allocation:

in group A; a curvilinear incision was taken in the groove between internal and external anal sphincters over the track course, it was deepened by sharp and blunt dissection between both sphincters till reaching the propped fistulous track, using monopolar diathermy when needed, the track was dissected all around at this point, we used Vicryl 3\0 suture to ligate the fistulous track at two points the medial one as near as possible to the internal sphincter the lateral one is close as possible to the external sphincter, the track was cut in between both ligatures, the lateral part of the track was curetted and the skin around the internal opening was trimmed.

In group B; after identification and probing of the track fistulectomy was carried out by carrying out elliptical incision including internal and external openings, the fistulous track was excised severing the related part of the anal sphincters.

Hemostasis was achieved as needed, wounds was dressed using non adherent dressing, patients received non-steroidal analgesia as per need, patients was discharged after tolerating oral intake.

Follow up; It was achieved via outpatient clinics by the attending surgeon,participants were instructed to attend the clinic every week till complete wound healing , 3 and 6 months after wound healing, later on patients were contacted by phone after 1 year of the procedure, data to be collected throughout follow up included postoperative pain measured by visual analogue scale (VAS) , state of wound healing, state of continence measured by Vaizey score patient's questionnaire, recurrence or persistence of the fistula measured by history and clinical examination.

Statistical analysis; Operative and hospital stay time together with follow up data were collected and statistically analyzed using paired t test and Z test in SPSS program package 22

Inclusion Criteria:

• patients with transsphincteric anal fistula

Exclusion Criteria:

• Anorectal malignancy.
• Patient with previous radiotherapy to the region.
• Those with fistula due to specific disease as Crohn's disease.
• Patients with anal incontinence.
• Patients with perianal collections.
• Patients on cytotoxic or immunosuppressive therapy.