Abstract: Disclosed is a surgical instrument for insertion into a blood-vessel lumen and comprises a separable assembly of longitudinal sections in mating relationship having tube and hub sections. Twisting movement of lateral separator tabs integral with the proximal ends of the hub sections effects relative movement to initially unlock releasable interdigitation locking means which the tube sections incorporate distally, and which the hub sections incorporate both distally and proximally, with such continued relative movement causing biased interfaces on the hub sections to cam open and force apart the longitudinal sections.

Abstract: Discloses a device for the external fixation of the barium enema tip inserted into the patient's rectum. The device has a waist band, anterior and posterior straps suitably attached to the waist band a locking ring for releasable and removable locking engagement with a locking groove on the barium enema tip. The barium enema tip has a lumen communicating with side holes, a proximal end having a raised ridge to thereby receive and retain enema-bag tubing, a distal end, and an hour-glass shaped cuff having a concave portion whereby the anal sphincter complementally receives and locks thereon to prevent leakage of barium liquid.