A case study of magnetic resonance imaging of cerebrovascular reactivity: a powerful imaging marker for mild traumatic brain injury.
OBJECTIVE
To use breath-hold functional magnetic resonance imaging (fMRI) to localize the brain regions with impaired cerebrovascular reactivity (CVR) in a female patient diagnosed with mild traumatic brain injury (mTBI). The extent of impaired CVR was evaluated 2 months after concussion. Follow-up scan was performed 1 year post-mTBI using the same breath-hold fMRI technique.


METHODS
Case report.


METHODS
fMRI blood oxygenation dependent level (BOLD) signals were measured under breath-hold challenge in a female mTBI patient 2 months after concussion followed by a second fMRI with breath-hold challenge 1 year later. CVR was expressed as the percentage change of BOLD signals per unit time of breath-hold.


RESULTS
In comparison with CVR measurement of normal control subjects, statistical maps of CVR revealed substantial neurovascular deficits and hemispheric asymmetry within grey and white matter in the initial breath-hold fMRI scan. Follow-up breath-hold fMRI performed 1 year post-mTBI demonstrated normalization of CVR accompanied with symptomatic recovery.


CONCLUSIONS
CVR may serve as an imaging biomarker to detect subtle deficits in both grey and white matter for individual diagnosis of mTBI. The findings encourage further investigation of hypercapnic fMRI as a diagnostic tool for mTBI.
Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging and.
Suk-tak
ST
Chan
Karleyton C
KC
Evans
Bruce R
BR
Rosen
Tian-yue
TY
Song
Kenneth K
KK
Kwong
D015415:Biomarkers; D001930:Brain Injuries / Q000473:pathology / Q000503:physiopathology*; D062485:Breath Holding; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D006935:Hypercapnia / Q000097:blood / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D020127:Recovery of Function; D013997:Time Factors
D015415:Biomarkers; D010100:Oxygen
Cerebrovascular reactivity; functional magnetic resonance imaging; mild brain injury