A. Normal: Disc location is normal on closed- and open-mouth images.
B. Disc displacement with reduction: Disc location is displaced on closed-mouth images but normal in open-mouth images.
C. Disc displacement without reduction: Disc location is displaced on closed-mouth and open-mouth images.
D. Indeterminate: Disc location is not clearly normal or displaced in the closed-mouth position.
E. Disc not visible: Neither signal intensity nor outlines make it possible to define a structure as the disc in the closed-mouth and open-mouth views. If the images are of adequate quality in visualizing other structures in the TMJ, then this finding is interpreted to indicate a deterioration of the disc, which is associated with advanced disc pathology.