title: In vivo proton MR three-dimensional T1rho mapping of human articular cartilage: initial experience.
abstract: The purpose of this study was to demonstrate the feasibility of computing three-dimensional relaxation maps of spin-lattice relaxation time in the rotating frame (T1rho) from in vivo magnetic resonance (MR) images of the human patellofemoral joint. T1rho was measured by applying a three-dimensional gradient-echo pulse sequence in six healthy subjects and one symptomatic subject by using a 1.5-T MR imager and a 15-cm-diameter transmit-receive quadrature birdcage radiofrequency coil. Average T1rho measured in healthy patellar cartilage was 49.7 msec +/- 3.2 (mean +/- SD). Two-dimensional T1rho-weighted images were obtained with a fast spin-echo pulse sequence for comparison. There was good correlation between two-dimensional and three-dimensional T1rho values for the six healthy subjects (R2 = 0.88, slope = 1.16).
authors.affiliation: MMRRCC, Department of Radiology, B1, Stellar-Chance Laboratories, University of Pennsylvania Medical Center, 422 Curie Blvd, Philadelphia, PA 19104-6100, USA. regatte@mail.mmrrcc.upenn.edu
authors.forename: Ravinder Reddy
authors.initials: RR
authors.lastname: Regatte
authors.forename: Sarma V S
authors.initials: SV
authors.lastname: Akella
authors.forename: Arijitt
authors.initials: A
authors.lastname: Borthakur
authors.forename: J Bruce
authors.initials: JB
authors.lastname: Kneeland
authors.forename: Ravinder
authors.initials: R
authors.lastname: Reddy
mesh_terms: D000328:Adult; D002358:Cartilage, Articular / Q000033:anatomy & histology* / Q000473:pathology; D005260:Female; D005269:Femur / Q000033:anatomy & histology / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007719:Knee Joint / Q000033:anatomy & histology* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis; D010329:Patella / Q000033:anatomy & histology / Q000473:pathology