To evaluate the relative sensitivity of MR scanning for multiple sclerosis (MS) at 1.5 Tesla (T) and 3.0 T using identical acquisition conditions, as is typical of multicenter clinical trials.
Twenty-five subjects with MS were scanned at 1.5 T and 3.0 T using fast spin echo, and T1-weighted SPGR with and without gadolinium contrast injections. Image data, blinded to field strength, were analyzed using automated segmentation and lesion counting.
Relative to scanning at 1.5 T, the 3.0 T scans showed a 21% increase in the number of detected contrast enhancing lesions, a 30% increase in enhancing lesion volume and a 10% increase in total lesion volume.
The improved detection ability using high-field MR imaging is prominent even when sequence parameters are optimized around the midfield units. Multicenter trials using both 1.5 T and 3.0 T instruments may be affected by these sensitivity differences.
*Department of Neurology, †Division of Brain Mapping, ‡Department of Molecular and Medical Pharmacology, §Department of Radiological Sciences, ¶Department of Psychiatry and Biobehavioral Sciences, and ∥Department of Biomedical Physics, University of California Los Angeles, Los Angeles, CA.
Received September 29, 2002, and accepted for publication, after revision, January 18, 2003.
Reprints: Nancy L. Sicotte, MD. E-mail: email@example.com
Supported by Clinical Investigator Award (NINDS K08/NS02044) (NLS) and the National Multiple Sclerosis Society, RG3016 (R.R.V.) with supplemental funds from the Colorado Chapter of the National MS Society (Denver, Colorado) and the Tom Sherak Family Foundation (Los Angeles, CA). N. L. Sicotte (JF2107) and R. R. Voskuhl (JF2094) are both Harry Weaver Neuroscience Scholars of the National Multiple Sclerosis Society. Other support was from Brain Mapping Medical Research Organization, Brain Mapping Support Foundation, Pierson-Lovelace Foundation, The Ahmanson Foundation, Tamkin Foundation, Jennifer Jones-Simon Foundation, Capital Group Companies Charitable Foundation, Robson Family, Northstar Fund, National Center for Research Resources grants RR12169 and M01 RR00865. M.S. Cohen is supported under NIDA DA15549, DA13627 and NEI EY12722.