GANGLION CYSTS OF THE KNEE - ARTICULAR COMMUNICATION REVEALED BY DELAYED RADIOGRAPHY AND CT AFTER ARTHROGRAPHY

OBJECTIVE. The diagnosis of ganglion cysts of articular origin may som etimes be uncertain when communication with the joint is not evident. Because we have observed that opacification of ganglion cysts revealed by arthrography can be significantly delayed, the purpose of this stu dy was to determine retrospectively in 20 cases the time delay needed to show with arthrography a communication between the articular cavity and ganglion cysts of the knee. CONCLUSION. Arthrographic evidence of a communication between the articular cavity of the knee and communic ating ganglion cysts requires delayed radiography performed at least 1 hr after intraarticular injection of contrast material. The best resu lts are obtained with additional CT performed 1-2 hr after injection.