Traumatic cerebrovascular injury (TCVI) is common after traumatic brain injury (TBI) and an attractive target for therapeutic intervention. We will longitudinally measure cerebrovascular reactivity (CVR) by functional near-infrared spectroscopy (fNIRS) in acute (3 days from injury), subacute, and chronic phases after TBI as a biomarker of TCVI as compared to healthy controls. CVR will be measured by fNIRS response to hypercapnia. We hypothesize that CVR will be decreased after TBI and that these decreases will correlate with clinical outcomes. Furthermore, we predict that administration of a vasodilatory medication (sildenafil) will augment CVR after TBI.

You may be eligible for this study if you meet the following criteria:

• Conditions: TBI
• Age: 99 years or below
• Gender: All