Jalal Badi Andre MD, Presenter: Nothing to Disclose

Greg Zaharchuk MD, PhD, Abstract Co-Author: Advisory Board Member, General Electric Company Research support, General Electric Company

Emine Ulku Saritas PhD, Abstract Co-Author: Nothing to Disclose

Cynthia T. Chin MD, Abstract Co-Author: Nothing to Disclose

Dwight G Nishimura PhD, Abstract Co-Author: Nothing to Disclose

Ajit Shankaranarayanan PhD, Abstract Co-Author: Nothing to Disclose

Nancy Jane Fischbein MD, Abstract Co-Author: Nothing to Disclose

To compare the performance of reduced field-of-view (rFOV) spinal cord diffusion-weighted imaging (DWI) (Saritas et al., Magn Reson Med 2008) with that of full FOV (fFOV) echo-planar imaging (EPI) in a clinical population.

Consecutive patients with clinically necessary cervical or thoracic spine imaging underwent sagittal diffusion imaging at 1.5 T using a rFOV approach (b=500 s/mm2) via RF excitement of a rectangular slab. A subset of patients underwent additional comparison imaging with two separate standard fFOV EPI sequences, matched for either spatial resolution or readout time. Apparent diffusion coefficient (ADC) maps were created for all three methods. Two neuroradiologists were asked to rate image quality on a five-point scale, assessing perceived susceptibility artifacts, spatial resolution, signal-to-noise, anatomic detail, and clinical utility.

Of 211 patients that met inclusion criteria, 36 underwent fFOV comparison imaging. Agreement between readers, assessed with weighted kappa and exact Bowker test of symmetry, was moderate, with a trend for agreement to be higher for rFOV than fFOV. All three sequences were significantly different from each other on all ratings, with rFOV having consistently higher ratings than either fFOV sequence (all calculated p-values < or = 0.0001). ADC values for the rFOV and fFOV sequences were not statistically different (ANOVA F=2.747, p>0.05) and correlated well with each other (R=0.52-0.55).

rFOV diffusion imaging of the spinal cord is feasible in a clinical population, generates ADC values that are comparable to conventional fFOV approaches, and overcomes many of the limitations associated with standard fFOV EPI. The rFOV DWI method generates images that are deemed clinically superior to those created with standard fFOV methods, and may serve as the future basis for human spinal cord diffusion tensor imaging.

Spinal cord rFOV DWI may further characterize pathology, including demyelinating disease, acute infarction, infection, and traumatic injury, and provide the future basis for diffusion tensor imaging.

Andre, J, Zaharchuk, G, Saritas, E, Chin, C, Nishimura, D, Shankaranarayanan, A, Fischbein, N, Clinical Evaluation of Reduced Field-of-View Diffusion-weighted Imaging of the Human Spinal Cord  .  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9013501.html