Simultaneous acquisition of T1ρ and T2 quantification in knee cartilage: Repeatability and diurnal variation. Issue 5 (29th July 2013)

• Record Type: Journal Article
• Authors: Li, Xiaojuan; Wyatt, Cory; Rivoire, Julien; Han, Eric; Chen, Weitian; Schooler, Joseph; Liang, Fei; Shet, Keerthi; Souza, Richard; Majumdar, Sharmila
• Is Part Of: Journal of magnetic resonance imaging. Volume 39:Issue 5(2014)
• Page Start: 1287
• Page End: 1293
• Publication Date: 2013-07-29
• Subjects: Magnetic resonance imaging -- Periodicals; 616
• DOI: 10.1002/jmri.24253
• Languages: English
• ISSNs: 1053-1807

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="jmri24253-sec-0001" sec-type="section"> <title>Purpose</title> <p>To develop a robust sequence that combines T<sub>1ρ</sub> and T<sub>2</sub> quantifications and to examine the in vivo repeatability and diurnal variation of T<sub>1ρ</sub> and T<sub>2</sub> quantifications in knee cartilage.</p> </sec> <sec id="jmri24253-sec-0002" sec-type="section"> <title>Materials and Methods</title> <p>Six healthy volunteers were scanned in the morning and afternoon on 2 days using a combined T<sub>1ρ</sub> and T<sub>2</sub> quantification sequence developed in this study. Repeatability of T<sub>1ρ</sub> and T<sub>2</sub> quantification was estimated using root‐mean‐square coefficients‐of‐variation (RMS‐CV). T<sub>1ρ</sub> and T<sub>2</sub> values from morning scans were compared to those from afternoon scans using paired <italic>t</italic>‐tests.</p> </sec> <sec id="jmri24253-sec-0003" sec-type="section"> <title>Results</title> <p>The overall RMS‐CV of in vivo T<sub>1ρ</sub> and T<sub>2</sub> quantification was 5.3% and 5.2%, respectively. The RMS‐CV of <sc>am</sc> scans was 4.2% and 5.0% while the RMS‐CV of <sc>pm</sc> scans was 6.0% and 6.3% for T<sub>1ρ</sub> and T<sub>2</sub>, respectively. No significant difference was found between T<sub>1ρ</sub> or T<sub>2</sub> values in the morning and in the afternoon.</p> </sec> <sec id="jmri24253-sec-0004" sec-type="section"> <title>Conclusion</title> <p>A sequence that combines T<sub>1ρ</sub> and T<sub>2</sub> quantification with scan time less than 10 minutes and is robust to B<sub>0</sub> and B<sub>1</sub> inhomogeneity was developed with excellent repeatability. For a cohort with low‐level daily activity, although no significant diurnal variation of cartilage MR relaxation times was observed, the afternoon scans had inferior repeatability compared to morning scans. <bold>J. Magn. Reson. Imaging 2014;39:1287–1293</bold>. © <bold>2013 Wiley Periodicals, Inc</bold>.</p> </sec> </abstract>