Abstract: An anoscope for use with a medical instrument insertable within the interior of the anoscope. The anoscope comprises a tubular member having a longitudinal axis with a proximal end and a distal end. The distal end is insertable into the rectum of a patient while the proximal end remains outside the body. A first longitudinal slot extends from the distal end toward the proximal end, and a second longitudinal slot extends from the proximal end toward the distal end. The first and second longitudinal slots are separated by about 180° on the surface of the tubular member. The first longitudinal slot is adapted to permit access to a site to be treated within the rectum and the second longitudinal slot is adapted to accommodate pivoting of the medical instrument at an angle to the longitudinal axis of the tubular member to improve access to the site to be treated.