In treatment of perianal fistula several methods are described. However, since the Hippocrates basics of surgical treatment has not changed very much. the aim of this study is to evaluate the effectiveness of PRP gel in treatment of perianal fistula.

Perianal fistula is a chronic condition that seriously affects the patients' quality of life. There are different treatment modalities used in treatment. Recently sphincter preserving methods are becoming more popular with low complication rates. Most of this methods aiming the closure of fistula tract by different pathways.

Platelet rich plasma (PRP) is used in a wide range of conditions in medicine. The investigator's team showed the effective treatment of pilonidal disease by use of PRP gel. In the recent study, aim to evaluate the effectiveness of PRP gel in treatment of perianal fistula.

Patients with perianal fistula will be evaluated for the study. After taking permission with informed consent; cases will be included in the study. Cases with inflammatory bowel disease, platelet function disorders or connective tissue disorders that may alter wound healing will be excluded from the study.

After, PRP application to the fistula tract patients will be taken to follow up. Perianal fistulas will be followed by magnetic resonance imaging 1 month after the application. Pre-application and post-application scans will be used for the evaluation of the treatment success.

Inclusion Criteria:

• patients with perianal fistula
• signing the informed consent form
• above the age of 18

Exclusion Criteria:

• inflammatory bowel disease
• previous radiation therapy
• having connective tissue disorders