title: High-resolution MR imaging of triangular fibrocartilage complex (TFCC): comparison of microscopy coils and a conventional small surface coil.
abstract: OBJECTIVE
  To compare MR images of the triangular fibrocartilage complex (TFCC) using microscopy coils with those using a conventional surface coil qualitatively and quantitatively.
  
  
  METHODS
  Proton density-weighted images and T2*-weighted images of the TFCC from ten normal volunteers were obtained with a conventional surface coil (C4 coil; 80 mm in diameter), a 47-mm microscopy surface coil and a 23-mm microscopy surface coil) at 1.5 T. Qualitative image analysis of MR images with three coils was performed by two radiologists who assigned one of five numerical scores (0, nonvisualization; 1, poor; 2, average; 3, good; 4, excellent) for five TFCC components, which were disc proper, triangular ligament, meniscus homologue, ulnotriquetral and ulnolunate ligament. Quantitative analysis included the signal-to-noise ratio (S/N) of the disc proper of TFCC, the lunate cartilage, the lunate bone and the contrast-noise-ratio (C/N) between articular cartilage and disc proper or bone marrow were measured.
  
  
  RESULTS
  All structures show higher scores qualitatively on MR with microscopy coils than those with a C4 coil, and the difference was significant with the exception of the ulnolunate ligament. MR with microscopy coils showed significantly higher S/N values than those with a conventional surface coil (P<0.05 to P<0.001). T2*-weighted images using microscopy coils showed significantly higher cartilage-disc proper C/N and cartilage-bone marrow C/N (P<0.01 to P<0.001). On proton density-weighted images, the C/N between cartilage and disc proper with two microscopy coils was significantly higher (P<0.01) than that with a conventional coil.
  
  
  CONCLUSIONS
  High-resolution MR images of the normal wrist using microscopy coils were superior to those using a conventional surface coil qualitatively and quantitatively. High-resolution MR imaging with a microscopy coil would be a promising method to diagnose TFCC lesions.
authors.affiliation: Department of Radiology, University of Tsukuba, Tsukuba, Japan. hyoshioka@partners.org
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yoshioka
authors.forename: Teruko
authors.initials: T
authors.lastname: Ueno
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Tanaka
authors.forename: Masashi
authors.initials: M
authors.lastname: Shindo
authors.forename: Yuji
authors.initials: Y
authors.lastname: Itai
mesh_terms: D000328:Adult; D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008853:Microscopy / Q000295:instrumentation; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014955:Wrist Joint / Q000473:pathology*