The Application Value Of Magnetic Susceptibility-weighted Imaging In The Diagnosis Of Mild Traumatic Brain Injury

Objective: To explore the clinical value of susceptibility-weighted imaging(SWI) in the diagnosis of mild traumatic brain injury(mTBI) and its relationship with prognosis, through sensitivity differences contrast between SWI and conventional magnetic resonance sequences(T1WI, T2 WI, T2-FLAIR) in detection of mTBI hemorrhages.Methods: Seventy-eight patients diagnosed mTBI with normal CT imaging were included in this study. SWI and conventional MR sequences were performed after 3±2 days of traumatic brain injury. Imaging characteristics every sequence showed were analyzed and numbers and distributions of hemorrhages were recorded. The sensitivity in detection of mTBI hemorrhages between SWI and conventional magnetic resonance sequences were compared. Correlation analysis was performed between hemorrhages number and Glasgow Coma Scale(GCS) on admission and prognosis. Fifty healthy controls were included in order to analyze the lesions distribution in contrast with mTBI group.Results: Thirty-one patients on SWI and seventeen patients on conventional MR presented hemorrhages. SWI detected 156 lesions in thirty-one patients while conventional MR(T1WI,T2 WI,T2-FLAIR) detected 16,26,37 lesions. Hemorrhages were detected in more patients and more patients were detected on SWI than conventional MR by Wilcoxon signed rank sum test(P=0.000). Spearman’s rank analysis showed significant inverse correlations between GCS score and hemorrhages number(rs=-0.471, P=0.008). GCS score was higher in SWI(+) group than SWI(-) group by Mann-Whitey U test(Z=-3.956, P=0.000). On SWI, SWI(+) group had a higher rate of post-concussion symptoms(PCS) than did the SWI(-) group(χ2=7.496, P=0.006). Among patients that had exhibited hemorrhagic lesions, the number of lesions were greater in the PCS(+) group than the PCS(-) group(Z=-2.226, P=0.026).Three lesions were found in three control subjects,and they showed all lesions in the basal ganglia.Conclusion: SWI is more sensitive than conventional MR sequences in detecting hemorrhagic foci in mTBI patients. Bleeding detection and quantity were correlated with GCS on admission and prognosis.