Figure 12b. Arthroscopically proved rotator interval defect with thickened, scarred, and redundant rotator interval tissue. The subscapularis tendon was partially torn, with long head of the biceps brachii tendon encased by bone. (a-c) Transverse T1-weighted MR arthrographic images (700/10) obtained with fat saturation after intraarticular administration of dilute gadolinium compound show thickened tissue of rotator interval (black arrowhead). High-signal-intensity cleft in a is consistent with contrast agent extension (white arrowhead). Long head of biceps brachii tendon (arrow) is almost completely encased by bone.