High-resolution MR imaging of the proximal zone of the lunotriquetral ligament with a microscopy coil.
OBJECTIVE
To evaluate high-resolution MRI of the proximal zone of the lunotriquetral ligament (LTL) using a microscopy surface coil with a 1.5 T scanner.


METHODS
The proximal zone of the LTL was reviewed in 90 subjects (23 asymptomatic normal volunteers and 67 patients with suspicion of triangular fibrocartilage complex injury) with high-resolution MRI using a 47-mm microscopy surface coil. High-resolution MR images were obtained with gradient recalled echo (GRE) T2*-weighted sequence and short tau inversion recovery imaging, with a 1- to 1.5-mm slice thickness, a 50-mm field of view, an imaging matrix of 140-224x512 using zero fill interpolation, and 3-4 excitations. As a qualitative analysis, the LTL was classified in shape and signal intensity.


RESULTS
The triangle-shaped low-signal-intensity LTL was identified in 77 of 90 subjects (85.6%) on GRE images. The triangle was classified as regular (41.1%), broad-based (20.0%), narrow-based (6.7%), or asymmetrical (17.8%). The bar-shaped ligament was seen in one patient, and unclassified ligaments were seen in 12 patients. All volunteers showed triangle-shaped LTL. The MR signal intensity of the proximal zone in the LTL was characterized as homogeneously low intensity (type 1; 33.8%), linear intermediate or high signal intensity traversing the distal surface of the LTL (type 2; 45.5%), and linear intermediate or high intensity traversing both distal and proximal surfaces of LTL (type 3; 20.8%).


CONCLUSIONS
The proximal zone of the LTL showed a broad spectrum of normal variations in shape and signal intensity on high-resolution MR images with a microscopy coil.
Department of Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA. hyoshioka@partners.org
Hiroshi
H
Yoshioka
Toshikazu
T
Tanaka
Teruko
T
Ueno
Masashi
M
Shindo
John A
JA
Carrino
Philipp
P
Lang
Carl S
CS
Winalski
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation* / Q000379:methods; D008023:Ligaments, Articular / Q000293:injuries* / Q000473:pathology*; D012667:Lunate Bone / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D008280:Magnetics / Q000295:instrumentation*; D008297:Male; D008853:Microscopy / Q000295:instrumentation / Q000379:methods; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers; D014954:Wrist Injuries / Q000473:pathology*