MR imaging in the detection of diffuse axonal injury with mild traumatic brain injury

Purpose: To evaluate the occurrence and distribution of mild traumatic brain injury MTBI) caused by diffuse axonal injury DAI) using magnetic resonance MR) imaging and to attempt to correlate MR findings with post-concussion symptoms PCS). Patients and methods: Forty MTBI patients mean age: 32.5 years) with normal cranial computed tomography CT) findings were examined with standard MR protocol including T1-weighted, T(2)-weighted, fluid attenuated inversion recovery FLAIR), gradient echo GRE) and diffusion-weighted DW) sequences. MR imaging was performed within 24 hours of injury. The lesions were classified as DAI based on their location and morphologic appearance. Results: In MR imaging of five 12.5%) of the patients, the lesions compatible with DAI were observed. Four patients 10%) had the foci of low signal intensity compatible with hemorrhagic shear injury on the GRE sequence, and five 12.5%) patients had high signal intensity on FLAIR and DW sequence. Conclusion: MR imaging can be helpful in revealing DAI lesions in patients with normal CT scan findings after MTBI. FLAIR, GRE and DW sequences are superior to conventional spin-echo images in detecting DAI lesions. [Neurol Res 2008; 30: 974-978]