Department of General and Digestive Surgery;
Hospital Clínico Universitario;
Colorectal Unit;
Department of General and Digestive Surgery;
Hospital Clínico Universitario;
tridimensional; endoanal; ultrasound; high; transsphincteric; fistula; perianal; fistula; intersphinteric; fistula; dimensional; endoanal; ultrasound;