Axonal Diameter Mapping as a biomarker for mTBI as detected by ultrahigh-bvalue DWI in a high performance Head-only gradient system, MAGNUS.

Motivation: Detect a mild traumatic brain injury with a reliable diagnostic for staging disease state and the testing therapies for treating the malady in acute and long term phase. Goal(s): Develop a MRI biomarker that can be repeated used on patients especially in the warfighter population which have more that 500,000 diagnosed mTBI over the past 30 year. Approach: Use of diffusion MRI to determine the white matter microstructural state namely the axon diameter. Results: MAGNUS SE-DWI high-B can detect changes in axon diameter and follow these changes in single subject over time. Impact: High B-value diffusion imaging (b > 30000 mm2/sec) can detect changes in mild TBI subjects that can be seen to progress through the recovery process. The high-performance gradient system, MAGNUS, (200mT/m, 500T/m/s) scanning without peripheral nerve stimulation in the subject.