Expanding the role of functional mri in rehabilitation research

Functional magnetic resonance imaging (fMRI) based on blood oxygenation level dependent (BOLD) contrast has become a universal methodology in functional neuroimaging. However, the BOLD signal consists of a mix of physiological parameters and has relatively poor reproducibility. As fMRI becomes a prominent research tool for rehabilitation studies involving repeated measures of the human brain, more quantitative and stable fMRI contrasts are needed. This dissertation enhances quantitative measures to complement BOLD fMRI. These additional markers, cerebral blood flow (CBF) and cerebral blood volume (CBV) (and hence cerebral metabolic rate of oxygen (CMRO₂) modeling) are more specific imaging markers of neuronal activity than BOLD. The first aim of this dissertation assesses feasibility of complementing BOLD with quantitative fMRI measures in subjects with central visual impairment. Second, image acquisition and analysis are developed to enhance quantitative fMRI by quantifying CBV while simultaneously acquiring CBF and BOLD images. This aim seeks to relax assumptions related to existing methods that are not suitable for patient populations. Finally, CBF acquisition using a low-cost local labeling coil, which improves image quality, is combined with simultaneous acquisition of two types of traditional BOLD contrast. The demonstrated enhancement of CBF, CBV and CMRO₂measures can lead to better characterization of pathophysiology and treatment effects.

Department dc:contributor.department

Biomedical Engineering

Grantor dc:publisher

Georgia Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Glielmi, Christopher B.

Advisor dc:contributor.advisor

• Hu, Xiaoping

Committee members dc:contributor.committeemember

• Benkeser, Paul
• Keilholz, Shella
• Sathian, Krish
• Schuchard, Ronald

• Rehabilitation
• Cerebral blood flow
• Cerebral blood volume
• Blood oxygenation level dependent
• Cerebral metabolic rate of oxygen
• Vascular space occupancy
• Low vision

Handle dc:identifier.uri

http://hdl.handle.net/1853/33972

OAI identifier oai:identifier

oai:repository.gatech.edu:1853/33972