Rapid 3D-T1ρ mapping of the knee joint at 3.0T with parallel imaging

✍ Scribed by S. Kubilay Pakin; Jian Xu; Mark E. Schweitzer; Ravinder R. Regatte

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 462 KB
• Volume: 56
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.20982

✦ Synopsis

Abstract

Three‐dimensional spin‐lattice relaxation time in the rotating frame (3D‐T~1ρ~) with parallel imaging at 3.0T was implemented on a whole‐body clinical scanner. A 3D gradient‐echo sequence with a self‐compensating spin‐lock pulse cluster was combined with generalized autocalibrating partially parallel acquisitions (GRAPPA) to acquire T~1ρ~‐weighted images. 3D‐T~1ρ~ maps of an agarose phantom and three healthy subjects were constructed using an eight‐channel phased‐array coil without parallel imaging and with parallel imaging acceleration factors of 2 and 3, in order to assess the reproducibility of the method. The coefficient of variation (CV) of the median T~1ρ~ of the agarose phantom was 0.44%, which shows excellent reproducibility. The reproducibility of in vivo 3D‐T~1ρ~ maps was also investigated in three healthy subjects. The CV of the median T~1ρ~ of the patellar cartilage varied between ∼1.1% and 4.3%. Similarly, the CV varied between ∼2.1–5.8%, ∼1.4–8.7%, and ∼1.5–4.1% for the biceps femoris and lateral and medial gastrocnemius muscles, respectively. The preliminary results demonstrate that 3D‐T~1ρ~ maps can be constructed with good reproducibility using parallel imaging. 3D‐T~1ρ~ with parallel imaging capability is an important clinical tool for reducing both the total acquisition time and RF energy deposition at 3T. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.