A quantitative analysis of head injury using T2*-weighted gradient-echo imaging

Background: T2*-weighted gradient-echo imaging (T2*-GE) is useful for detec ting small hemorrhages. Methods: Thirty-four patients were prospectively examined, first by magneti c resonance imaging (1.5 T) and then by T2-weighted fast spin echo (T2-FSE) and T2*-GE. Thereafter, the correlations between the T2-FSE or T2*-GE find ings and the clinical or computed tomography findings were analyzed. Results:The number of lesions detected by T2*-GE was 14.5 +/- 16.3 (mean +/ - SD, n = 34), which was significantly (p < 0.001) greater than that detect ed by T2-FSE (5.6 +/- 5.6, n = 34). The findings of T2*-GE correlated posit ively with both the duration of unconsciousness (R-2 = 0.74, p < 0.0001) an d with Glasgow Outcome Scale (R-2 = 0.81, p < 0.0001), whereas those of T2- FSE did not show any significant correlation. T2*-GE imaging could also det ect all areas responsible For focal neurologic signs 1 month after injury, whereas T2-FSE imaging detected only 22 of 33 such signs. Conclusion: T2*-GE was found to be useful for evaluating the clinical sympt oms of head injury.