Assessing validity of existing fistula-in-ano classifications in a cohort of 848 operated and MRI-assessed anal fistula patients – Cohort study

The commonly used fistula-in-ano classifications, Park or St. James's University hospital(SJUH), neither grade fistulas as per their severity nor guide regarding their management. A new classification(NC), published in 2017, proposed to classify fistulas as per their severity and also guided in its management. The early grades (NC grade I & II) were simple fistulas and were amenable to fistulotomy whereas higher grades (NC grade III-V) were complex fistulas and were not amenable to fistulotomy.