title: T1rho MRI at 3T of menisci in patients with acute anterior cruciate ligament (ACL) injury.
abstract: OBJECTIVE
  To explore the feasibility of T1rho mapping of menisci at 3T in discriminating between patients with acute anterior cruciate ligament (ACL) injury and healthy controls.
  
  
  METHODS
  Thirty-three subjects were included in the study and subdivided into two subgroups: 16 healthy controls (4 females, 12 males; mean age = 34.4 ± 10.2 years, age range 24-63 years), 17 patients with ACL injury (3 females, 14 males; mean age = 29.8 ± 10.8 years, age range 18-61 years). T1rho images from all subjects were acquired on a 3T MR scanner using a spin-lock-based 3D GRE sequence and computed for T1rho mapping. Clinical proton density (PD)-weighted fast spin echo (FSE) images in the sagittal (without fat saturation), axial, and coronal (fat-saturated) planes were also acquired for cartilage assessment using Whole-Organ MR Imaging Score (WORMS) grading. Mixed model two-way analysis of variance (ANOVA) was performed to determine whether there were any significant differences among subregional, compartmental, and whole structure T1rho values of meniscus between healthy controls and ACL-injured patients.
  
  
  RESULTS
  Lateral posterior (29 ± 8 msec) and medial central (25 ± 7 msec) meniscus subregions in healthy controls had significantly lower T1rho values (P < 0.05) than the corresponding meniscus subregions in ACL-injured patients. Significantly lower meniscus T1rho values (P < 0.05) were also identified in lateral compartment in healthy controls (26 ± 6 msec) than that of ACL-injured patients (33 ± 4 msec). Subjects' total WORMS between healthy controls and ACL-injured patients had significant differences (P < 0.05).
  
  
  CONCLUSIONS
  These preliminary results indicate that T1rho mapping is possibly feasible in detecting meniscus degeneration and may be useful in distinguishing ACL-injured patients.
authors.affiliation: Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York, University Langone Medical Center, New York, NY, USA; School of Radiation Medicine and Protection, Medical College of Soochow University; School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Suzhou, Jiangsu, China.
authors.forename: Ligong
authors.initials: L
authors.lastname: Wang
authors.forename: Gregory
authors.initials: G
authors.lastname: Chang
authors.forename: Jenny
authors.initials: J
authors.lastname: Bencardino
authors.forename: James S
authors.initials: JS
authors.lastname: Babb
authors.forename: Andrew
authors.initials: A
authors.lastname: Rokito
authors.forename: Laith
authors.initials: L
authors.lastname: Jazrawi
authors.forename: Orrin
authors.initials: O
authors.lastname: Sherman
authors.forename: Ravinder R
authors.initials: RR
authors.lastname: Regatte
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries; D016022:Case-Control Studies; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology*; D008875:Middle Aged
keywords: ACL tear; T1rho mapping; cartilage; meniscus; osteoarthritis