Reduced Field-of-View Diffusion Imaging of the Human Spinal Cord: Comparison with Conventional Single-Shot Echo-Planar Imaging

A 71-year-old woman with right-sided weakness and hemifacial spasm. Comparison of DWI by using either rFOV (A); fFOV matched to have the same readout time (with subsequently lower spatial resolution) (B); or fFOV matched to have the same spatial resolution, with increased readout time (and associated susceptibility artifacts) (C). All images were matched for acquisition time (2.5 minutes). Only the 4 central sections are shown. rFOV DWI demonstrates high spatial resolution with minimal artifacts and acceptable SNR.

rFOV (A), low-resolution fFOV (B), and high-resolution fFOV ADC maps (C) demonstrating the location of the ROI used for the ADC measurements, placed on the centermost section of the sagittal images at the level of C2–3.

Pooled reviewer ratings of anatomy (A), perceived resolution (B), perceived SNR (C), susceptibility artifact (D), and clinical utility (E) for each of the 3 assessed sequences: High-resolution fFOV (HiRes fFOV), low-resolution fFOV (LoRes fFOV), and rFOV. All 3 sequences were significantly different from each other on all ratings, with rFOV having consistently higher ratings than the LoRes fFOV sequence, which in turn was preferred over the HiRes fFOV sequence (all calculated P values ≤ .0001). All values are expressed as a percentage of total responses by both reviewers.

A 42-year-old woman with left-sided arm weakness and multiple posterior disk-osteophyte complexes, the largest of which is located at C4–5 (arrow). Sagittal T2-weighted (A), rFOV DWI (B), low-resolution fFOV DWI (C), and high-resolution fFOV DWI (D) are shown. The rFOV diffusion images significantly alleviate susceptibility and partial volume effects that cause pixel misregistration and image warping on the fFOV diffusion scans.