Measure of Cerebrovascular Dysfunction After TBI With fNIRS

Clinical Trial Summary

The goal of this project is to determine if it is possible to assess Cerebrovascular Reactivity (CVR) to hypercapnia with functional Near Infrared Spectroscopy (fNIRS). Such a method would be particularly helpful in traumatic brain injury (TBI), where objective measures are needed, and would greatly expand the capacity to make such assessments in standard clinical practice.

The prospective study design will consist of two study groups; the experimental group and the control group. In the Experimental Group (Group 1) we will enroll adult participants with TBI with persistent post-concussion symptoms or abnormalities on neuropsychological testing. In Group 2 we will enroll adult participants to serve as age and gender-matched healthy controls. Our goal is to recruit 100 subjects total in two groups of age and gender matched subjects, as follows: TBI (n = 50) and non-TBI (n = 50).

Participants in both groups will undergo NIRS testing with hypercapnia challenge, to measure the increase in hemodynamic flow signal during hypercapnia challenge via 2 methods, the breath holding and the Douglas bag methods. We will test intersessional validity of the NIRS-hypercapnia challenge in the first 20 (10 TBI and 10 non-TBI) subjects who are willing to return for a second visit of repeat testing.

The NIRS system is composed of 4 light sources and 10 detectors with a 16 point configuration system applied on the forehead of the subject. In our experiment, light intensity collected at each detector will be transformed into a signal related to the local concentrations of oxy- and de-oxyhemoglobin during the challenge. Each experiment will give a set of subject data, consisting of the peak amplitude and time-to-peak of the hemodynamic signals measured. ;

Study Design

Related Conditions & MeSH terms

• Brain Injuries
• Brain Injuries, Traumatic
• Post-Concussion Syndrome
• Traumatic Brain Injury