Enhancement of joint fluid with intravenously administered gadopentetate dimeglumine: technique, rationale, and implications.

This study reports findings on joint fluid enhancement after intravenous administration of gadopentetate dimeglumine. Ten subjects were studied: two asymptomatic volunteers and eight patients with suspected meniscal tears. The subjects underwent imaging at 1.5 T before, immediately after, and 42-60 minutes after intravenous administration of gadopentetate dimeglumine. The rate of fluid enhancement was assessed in three subjects, and the effects of exercise were studied. All subjects exhibited enhancement of joint fluid. Mean fluid enhancement for patients was 137% on initial and 262% on delayed images obtained after exercise. Exercise increased the rate and degree of fluid enhancement and distributed contrast material uniformly throughout the joint. The arthrographic effect of the fluid enhancement increased the number of perceived cartilage defects. This study documents enhancement of joint fluid in healthy subjects and in those with effusions. The arthrographic effect may provide a more convenient alternative to intraarticular injection of gadopentetate dimeglumine for MR arthrography.