Fractional anisotropy and mean diffusivity: comparison between 3.0‐T and 1.5‐T diffusion tensor imaging with parallel imaging using histogram and region of interest analysis

We performed a comparison study focusing on differences in fractional anisotropy (FA) and mean diffusivity (MD) between 3‐T and 1.5‐T diffusion tensor imaging (DTI) with parallel imaging. Thirty healthy volunteers underwent DTI with an eight‐channel phased‐array coil at both 3 T and 1.5 T. Histogram and region of interest (ROI) analyses were performed. Paired t tests were applied for statistical analysis. Signal‐to‐noise ratios of these regions were also measured. For histogram analysis, peak location of FA was significantly lower at 3 T than at 1.5 T (P = 0.04). Mean FA was significantly higher at 3 T than at 1.5 T (P = 0.002). Peak location of MD was significantly lower at 3 T than at 1.5 T (P < 0.001). Mean MD was significantly lower at 3 T than at 1.5 T (P < 0.001). In ROI analysis, FA was significantly larger at 3 T than at 1.5 T in the centrum semiovale (P < 0.001), middle cerebellar peduncle (P < 0.001), cerebral peduncle (P = 0.006), posterior limb of the internal capsule (P = 0.007), genu (P < 0.001) and splenium (P < 0.001). FA was significantly lower at 3 T than at 1.5 T in the globus pallidus (P < 0.001). MD was significantly smaller at 3 T than at 1.5 T in the globus pallidus (P = 0.007), thalamus (P < 0.001), centrum semiovale (P < 0.001), middle cerebellar peduncle (P < 0.001), cerebral peduncle (P = 0.01), posterior limb of the internal capsule (P < 0.001), genu (P = 0.01) and splenium (P < 0.001). Significant differences in FA and MD exist between 3 T and 1.5 T for whole‐brain histogram analysis and ROI analysis. Copyright © 2007 John Wiley & Sons, Ltd.

[1]  M Cercignani,et al.  Diffusion tensor magnetic resonance imaging in multiple sclerosis , 2001, Neurology.

[2]  M. Kraut,et al.  Comparison of weakness progression in inclusion body myositis during treatment with methotrexate or placebo , 2002, Annals of neurology.

[3]  Takashi Hanakawa,et al.  Diffusion-tensor fiber tractography: intraindividual comparison of 3.0-T and 1.5-T MR imaging. , 2006, Radiology.

[4]  P. Boesiger,et al.  SENSE‐DTI at 3 T , 2004, Magnetic resonance in medicine.

[5]  Y Tamagawa,et al.  Adult and neonatal human brain: diffusional anisotropy and myelination with diffusion-weighted MR imaging. , 1991, Radiology.

[6]  M S Buchsbaum,et al.  Whole-brain diffusion MR histograms differ between MS subtypes , 2000, Neurology.

[7]  T. Chenevert,et al.  Anisotropic diffusion in human white matter: demonstration with MR techniques in vivo. , 1990, Radiology.

[8]  C. Beaulieu,et al.  The basis of anisotropic water diffusion in the nervous system – a technical review , 2002, NMR in biomedicine.

[9]  Volkmar Glauche,et al.  Diffusion tensor MRI of early upper motor neuron involvement in amyotrophic lateral sclerosis. , 2004, Brain : a journal of neurology.

[10]  G. Barker,et al.  Diffusion tensor imaging of lesions and normal-appearing white matter in multiple sclerosis , 1999, Neurology.

[11]  Menelaos Malamas,et al.  Fractional anisotropy and mean diffusivity measurements on normal human brain: comparison between low- and high-resolution diffusion tensor imaging sequences , 2005, European Radiology.

[12]  Peter Stoeter,et al.  Functional implications of hippocampal volume and diffusivity in mild cognitive impairment , 2005, NeuroImage.

[13]  E Moser,et al.  Multivoxel 3D proton spectroscopy in the brain at 1.5 versus 3.0 T: signal-to-noise ratio and resolution comparison. , 2001, AJNR. American journal of neuroradiology.

[14]  Derek K. Jones,et al.  Diffusion‐tensor MRI: theory, experimental design and data analysis – a technical review , 2002 .

[15]  Susumu Mori,et al.  Fiber tracking: principles and strategies – a technical review , 2002, NMR in biomedicine.

[16]  Raja Muthupillai,et al.  Implications of SENSE MR in routine clinical practice. , 2003, European journal of radiology.

[17]  R Stollberger,et al.  Magnetic resonance diffusion tensor imaging for characterizing diffuse and focal white matter abnormalities in multiple sclerosis , 2000, Magnetic resonance in medicine.

[18]  M. Filippi,et al.  Inter-sequence and inter-imaging unit variability of diffusion tensor MR imaging histogram-derived metrics of the brain in healthy volunteers. , 2003, AJNR. American journal of neuroradiology.

[19]  G. Scotti,et al.  Quantification of tissue damage in AD using diffusion tensor and magnetization transfer MRI , 2001, Neurology.

[20]  P. Basser,et al.  MR diffusion tensor spectroscopy and imaging. , 1994, Biophysical journal.

[21]  M Hedehus,et al.  Diffusion-tensor MR imaging at 1.5 and 3.0 T: initial observations. , 2001, Radiology.

[22]  P. Basser,et al.  Diffusion tensor MR imaging of the human brain. , 1996, Radiology.

[23]  W. Edelstein,et al.  A signal-to-noise calibration procedure for NMR imaging systems. , 1984, Medical physics.

[24]  M. Bastin,et al.  A theoretical study of the effect of experimental noise on the measurement of anisotropy in diffusion imaging. , 1998, Magnetic resonance imaging.

[25]  G. Comi,et al.  Mean diffusivity and fractional anisotropy histograms of patients with multiple sclerosis. , 2001, AJNR. American journal of neuroradiology.

[26]  M A Horsfield,et al.  Diffusion tensor MRI assesses corticospinal tract damage in ALS , 1999, Neurology.

[27]  G. Comi,et al.  Pathologic damage in MS assessed by diffusion-weighted and magnetization transfer MRI , 2000, Neurology.

[28]  M E Bastin,et al.  Selecting an appropriate anisotropy index for displaying diffusion tensor imaging data with improved contrast and sensitivity , 2000, Magnetic resonance in medicine.