Traumatic brain injury (TBI) involves complex secondary injury processes following the primary injury. The secondary injury is often associated with rapid metabolic shifts and impaired brain function immediately after the initial tissue damage. Magnetic resonance spectroscopic imaging (MRSI) coupled with hyperpolarization of 13 C-labeled substrates provides a unique opportunity to map the metabolic changes in the brain after traumatic injury in real-time without invasive procedures. In this report, we investigated two patients with acute mild TBI (Glasgow coma scale 15) but no anatomical brain injury or hemorrhage. Patients were imaged with hyperpolarized [1-13 C]pyruvate MRSI 1 or 6 days after head trauma. Both patients showed significantly reduced bicarbonate (HCO 3 -) production, and one showed hyperintense lactate production at the injured sites. This study reports the feasibility of imaging altered metabolism using hyperpolarized pyruvate in patients with TBI, demonstrating the translatability and sensitivity of the technology to cerebral metabolic changes after mild TBI.

Sleep disturbances, including insomnia, circadian rhythm disturbances, and sleep apnea, are prevalent for all severities of traumatic brain injury (TBI), can be chronic, and affect both rehabilitation and recovery from the TBI. New knowledge of basic sleep mechanisms and neurochemistry has exploded in the last decade. In addition to known effects on mood and cognition from sleep deprivation in persons with TBI, new evidence indicates potential deleterious effects on neurorecovery and acceleration of long-term neurodegeneration.

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