Ruitian Song1, Alan R Cohen, Hee Kwon Song. 1. Laboratory for Structural NMR Imaging, Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania, USA.
Abstract
PURPOSE: To develop and validate an optimized respiratory-gated, gradient-echo sampling of free induction decay and echo (GESFIDE) pulse sequence for the simultaneous measurement of R2, R2*, and R2' in the liver or heart. MATERIALS AND METHODS: Fifteen subjects (12 thalassemia patients and three normal volunteers) were scanned using an optimized navigator-gated GESFIDE pulse sequence for the measurement of R2, R2*, and R2' in the liver and heart. For imaging the myocardium, dark-blood preparation was used to suppress the blood signal to improve accuracy. The results were compared with those obtained from breath-held GESFIDE and multi-gradient-echo (GRE) scans. RESULTS: Good agreement between breath-held and navigator-gated scans was found for R2, R2*, and R2' values in the liver (slopes = 0.97-0.99, r = 0.997-0.998, P < 0.0001) and for R2* in the heart (slope = 1.02, r = 0.85, P < 0.0001). Both R2* and R2' were closely correlated to R2 in the liver, with correlation factors of 0.998 and 0.994, respectively, but weaker correlations were observed in the heart (r = 0.72 for R2* vs. R2 and r = 0.51 for R2' vs. R2). CONCLUSION: The improved sequence enables free-breathing measurements of transverse relaxation rates of the myocardium and liver. The method precludes the need for multiple breath-held scans and possible misregistration issues, and may prove most beneficial for imaging young children and patients who may have difficulty with prolonged or repeated breath-holds. Copyright 2007 Wiley-Liss, Inc.
PURPOSE: To develop and validate an optimized respiratory-gated, gradient-echo sampling of free induction decay and echo (GESFIDE) pulse sequence for the simultaneous measurement of R2, R2*, and R2' in the liver or heart. MATERIALS AND METHODS: Fifteen subjects (12 thalassemiapatients and three normal volunteers) were scanned using an optimized navigator-gated GESFIDE pulse sequence for the measurement of R2, R2*, and R2' in the liver and heart. For imaging the myocardium, dark-blood preparation was used to suppress the blood signal to improve accuracy. The results were compared with those obtained from breath-held GESFIDE and multi-gradient-echo (GRE) scans. RESULTS: Good agreement between breath-held and navigator-gated scans was found for R2, R2*, and R2' values in the liver (slopes = 0.97-0.99, r = 0.997-0.998, P < 0.0001) and for R2* in the heart (slope = 1.02, r = 0.85, P < 0.0001). Both R2* and R2' were closely correlated to R2 in the liver, with correlation factors of 0.998 and 0.994, respectively, but weaker correlations were observed in the heart (r = 0.72 for R2* vs. R2 and r = 0.51 for R2' vs. R2). CONCLUSION: The improved sequence enables free-breathing measurements of transverse relaxation rates of the myocardium and liver. The method precludes the need for multiple breath-held scans and possible misregistration issues, and may prove most beneficial for imaging young children and patients who may have difficulty with prolonged or repeated breath-holds. Copyright 2007 Wiley-Liss, Inc.
Authors: M Beth McCarville; Claudia M Hillenbrand; Ralf B Loeffler; Matthew P Smeltzer; Ruitan Song; Chin-Shang Li; Jane S Hankins Journal: Pediatr Radiol Date: 2010-03-24
Authors: Ruitian Song; Ralf B Loeffler; Joseph L Holtrop; M Beth McCarville; Jane S Hankins; Claudia M Hillenbrand Journal: Magn Reson Med Date: 2017-10-30 Impact factor: 4.668
Authors: Jerry S Cheung; Wing-Yan Au; Shau-Yin Ha; Daniel Kim; Jens H Jensen; Iris Y Zhou; Matthew M Cheung; Yin Wu; Hua Guo; Pek-Lan Khong; Truman R Brown; Gary M Brittenham; Ed X Wu Journal: J Magn Reson Imaging Date: 2011-06 Impact factor: 4.813