Half-Fourier MR imaging of CNS disease.
Three MR imaging techniques were compared in 37 CNS examinations. In each case, postprocessing of a single data set in three different ways was used for comparison. Eleven of the 37 patients had a clinical diagnosis of multiple sclerosis. The primary purpose of this investigation was to evaluate the quality of the half-Fourier imaging technique. With half-Fourier imaging, scan time can be reduced by approximately half without compromising spatial resolution. In T2-weighted examinations at 1.0 T (with present instrumentation), application of the half-Fourier technique leads to a decrease in lesion detectability in patients with multiple sclerosis: this is because there is a reduction in the signal difference-to-noise ratio of 32 +/- 11%. For T2-weighted screening of the CNS on high-field MR systems, with the exception of multiple sclerosis, half-Fourier imaging may offer a suitable compromise by decreasing scan time while preserving spatial resolution. Application of the half-Fourier method to T1-weighted techniques also results in diagnostic-quality images.