title: Comparison of wideband steady-state free precession and T₂-weighted fast spin echo in spine disorder assessment at 1.5 and 3 T.
abstract: Wideband steady-state free precession (WB-SSFP) is a modification of balanced steady-state free precession utilizing alternating repetition times to reduce susceptibility-induced balanced steady-state free precession limitations, allowing its use for high-resolution myelographic-contrast spinal imaging. Intertissue contrast and spatial resolution of complete-spine-coverage 3D WB-SSFP were compared with those of 2D T₂-weighted fast spin echo, currently the standard for spine T₂-imaging. Six normal subjects were imaged at 1.5 and 3 T. The signal-to-noise ratio efficiency (SNR per unit-time and unit-volume) of several tissues was measured, along with four intertissue contrast-to-noise ratios; nerve-ganglia:fat, intradural-nerves:cerebrospinal fluid, nerve-ganglia:muscle, and muscle:fat. Patients with degenerative and traumatic spine disorders were imaged at both MRI fields to demonstrate WB-SSFP clinical advantages and disadvantages. At 3 T, WB-SSFP provided spinal contrast-to-noise ratios 3.7-5.2 times that of fast spin echo. At 1.5 T, WB-SSFP contrast-to-noise ratio was 3-3.5 times that of fast spin echo, excluding a 1.7 ratio for intradural-nerves:cerebrospinal fluid. WB-SSFP signal-to-noise ratio efficiency was also higher. Three-dimensional WB-SSFP disadvantages relative to 2D fast spin echo are reduced edema hyperintensity, reduced muscle signal, and higher motion sensitivity. WB-SSFP's high resolution and contrast-to-noise ratio improved visualization of intradural nerve bundles, foraminal nerve roots, and extradural nerve bundles, improving detection of nerve compression in radiculopathy and spinal-stenosis. WB-SSFP's high resolution permitted reformatting into orthogonal planes, providing distinct advantages in gauging fine spine pathology.
authors.affiliation: Department of Radiology, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Giovanna S
authors.initials: GS
authors.lastname: Danagoulian
authors.forename: Lei
authors.initials: L
authors.lastname: Qin
authors.forename: Krishna S
authors.initials: KS
authors.lastname: Nayak
authors.forename: Rivka R
authors.initials: RR
authors.lastname: Colen
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Mukundan
authors.forename: Mitchell B
authors.initials: MB
authors.lastname: Harris
authors.forename: Ferenc A
authors.initials: FA
authors.lastname: Jolesz
authors.forename: Ajit
authors.initials: A
authors.lastname: Shankaranarayanan
authors.forename: William A
authors.initials: WA
authors.lastname: Copen
authors.forename: Ehud J
authors.initials: EJ
authors.lastname: Schmidt
mesh_terms: D000368:Aged; D000465:Algorithms; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013113:Spin Labels; D013118:Spinal Cord Diseases / Q000473:pathology*; D013122:Spinal Diseases / Q000473:pathology*
chemical_list: D013113:Spin Labels