High-resolution MR imaging of the knee at 3 T.
OBJECTIVE
To examine the practical feasibility of using a 3.0-T MR unit to obtain high-quality, high-resolution images of the knee joint.


METHODS
One human cadaveric and 5 porcine knees were imaged with the 3.0-T unit. Sets of T1-weighted spin echo images were obtained with in-plane resolution of 0.195x0.39 mm and an acquisition time of approximately 5 min. Two porcine knees were also imaged with the 1.0-T unit with an identical imaging protocol and the signal-to-noise (S/N) ratios were measured on images at 3 T and 1 T.


RESULTS
The 3-T MR system provided detailed delineation of the knees. Deep layers of the medial collateral ligament and associated fine fibers beneath the medial and lateral collateral ligament were demarcated. We observed precise demonstration of the tibial attachment of the anterior cruciate ligament, irregularity of the meniscal free edge, and conjoint tendon formation together with the lateral collateral ligament and the biceps femoris tendon. Compared to the 1-T unit, the S/N ratio with the 3-T unit was increased by a factor of 1.39 to 1.72.


CONCLUSIONS
Due to the potential advantage of obtaining detailed images, the 3-T MR system suggests a practical utility for fine demonstration of the knee morphology.
Niitsu
M
M
Department of Radiology, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan.
Nakai
T
T
Ikeda
K
K
Tang
G Y
GY
Yoshioka
H
H
Itai
Y
Y
D000818:Animals; D006801:Humans; D007719:Knee Joint / Q000033:anatomy & histology*; D008023:Ligaments, Articular / Q000033:anatomy & histology; D008279:Magnetic Resonance Imaging / Q000379:methods; D013552:Swine