[MR imaging evaluation of plica synoviallis mediopatellaris of the knee joint].
To evaluate the diagnostic ability of MR imaging for plica synoviallis mediopatellaris (PSM), we retrospectively reviewed the MR imaging findings of patellofemoral space in 20 knee joints of 11 patients. In all 20 knee joints, arthroscopy and MR imaging were available. MR imaging was performed with a 1.5 Tesla Magnetom (Siemens) using a round surface coil. Pulse sequences were SE (TR 600 ms/TE 26 ms), SE (TR 200 ms/TE 26, 70 ms) and FLASH (TR 450 ms/TE 15 ms/FA 90 degrees). In six of the 20 knees with PSM proved by arthroscopy, a low intensity band was shown above the medial condyle of the femur on both T1- and T2-weighted MR images, and on FLASH images this band was shown as intermediate intensity. In the other 14 knees with no PSM observed by arthroscopy, the low intensity band was not shown on MR imaging. In all 20 knees, a similar low intensity band was shown about 1 cm cranial to the medial condyle of the femur. This should not be diagnosed as PSM. The low intensity band seen on T1- and T2-weighted MR images and its anatomical relation to the medial condyle are important in diagnosing PSM.
Nakanishi
K
K
Department of Radiology, Osaka University Medical School.
Inoue
M
M
Murakami
T
T
Tsuda
K
K
Mitani
T
T
Hashimoto
T
T
Maeshima
S
S
Tomoda
K
K
Hori
S
S
Nakamura
H
H
D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies; D013583:Synovial Membrane / Q000033:anatomy & histology*