[Magnetic resonance tomographic diagnosis of periarticular cystic space-occupying lesions in the knee joint].

The MR images of the knee joint of 100 successively examined patients were evaluated in retrospect with regard to periarticular cystic lesions. There were 18 popliteal cysts, 8 meniscal cysts and 4 ganglion cysts. Localisation and internal structure of the lesions were of main importance in respect of differential diagnosis. All meniscal cysts were associated with horizontal meniscal tears. Spin-echo and 3D gradient-echo images did not enable differentiation because of signal intensity values. A spin-echo sequence with long repetition time in double-echo technique was best suited to assess the periarticular cystic lesions as well as the intraarticular pathological changes which were often concomitant.