
Head trauma with sunsequent injury to the underlying brain tissue with or without intracranial bleeding can be extensive and obvious clinically but can also be occult and difficult to diagnose even with the best of clinical Neurological and Psychological testing. Subtle cases of traumatic brain injury (TBI) may evolve into chronic traumatic encephalopathy (CTE) and may be responsible for significant interference with the activities of daily living. While even the best quality Neuro-anatomical structural imaging may still not uncover responsible brain pathology, newer functional brain MRI techniques on the 3.0 Tesla scanner promise to be more successful.
Of particular utility are the functional BOLD 3.0 Tesla MRI sequences (VEN_BOLD SWI) which are as much as 4 -6 times more sensitive than gradient echo (GRE) T2* 1.5 Tesla images and twice as sensitive as 3.0 Tesla GRE sequences at detecting occult micro-hemorrhages in the brain which might be associated with axonal shear injury. Overall, the SWI sequences are roughly 6 times more likely than routine, non-susceptibility 1.5 Tesla imaging to detect old blood deposits in brain.
Left: routine T2-weighted. Right: VEN_BOLD SWI
Two arrows on micro-bleeds in brainstem (Duret Hemorrhages)and one arrow in the temporal lobe are pointing to tiny deposits of hemosiderin (old blood profucts which last forever in the brain once they occur) that cannot be seen on the routine T2- weighted MRI images at left, even though they are excellent.
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