Magnetization transfer imaging in the detection of injury associated with mild head trauma

BACKGROUND AND PURPOSE: Most traumatic brain injuries are classified as mil d, yet in many instances cognitive deficits result, The purpose of this stu dy was to investigate possible relationships between quantitative magnetiza tion transfer imaging (MTI) and neurocognitive findings in a cohort of pati ents with mild head trauma but negative findings on conventional MR images. METHODS: We examined 13 patients and 10 healthy volunteers with a standard MR protocol including fast spin-echo and gradient-echo imaging, to which wa s added quantitative MTI, MTI was performed with a modified gradient-echo s equence incorporating pulsed, off-resonance saturation. Both region-of-inte rest analysis and contour plots were obtained from the MTI data. A subgroup of nine patients was examined with a battery of neuropsychological tests, comprising 25 measures of neurocognitive ability. RESULTS: The magnetization transfer ratio (MTR) in the splenium of the corp us callosum was lower in the patient group as compared with the control gro up, but no significant reduction in MTR was found in the pens. Individual r egional MTR values were significantly reduced in two cases, and contour plo t analysis revealed focal areas of abnormality in the splenium of four pati ents. All the patients showed impairment on at least three measures of the neuropsychological test battery, and in two cases a significant correlation was found between regional MTR values and neuropsychological performance. CONCLUSION: Our results suggest that MTI and contour plot analysis may add sensitivity to the MR imaging examination of patients with traumatic brain injury.