How improvements in MRI signal-to-noise can advance fMRI

Event Date: March 20, 2008
Speaker: Dr. Jerzy Bodurka
Speaker Affiliation: National Institute of Mental Health
Sponsor: Medical Imaging Seminar
Time: 1:30 PM
Location: MJIS (BMED) Room 2001
Contact Name: Profs Tom Talavage and Charles Bouman
Contact Phone: 765-494-5475 or 765-494-0340
Contact Email: tmt@purdue.edu or bouman@purdue.edu
Open To: ACCEPTABLE FOR ECE694A

Signal-to-noise ratio (SNR) is one of the key parameters for conducting successful MRI studies. In this talk I will describe the recent advancement in MRI parallel receiver and surface coil array technologies, which resulted in substantial increases of SNR available for imaging experiments including anatomical and functional MRI BOLD studies. In BOLD fMRI, the temporal signal-to-noise ratio (TSNR) determines temporal stability of measured time courses and therefore, the outcome of the functional experiments. I will discuss the relationship of the TSNR and SNR and the role of the physiological noise which is inherently present during functional scans. The choice of the voxel volume for fMRI studies, as well as scan duration, will also be discussed.  I will show examples of how SNR improvements translate to higher spatial resolution for fMRI, which helps with BOLD spatial specificity and allows for unraveling functional architecture within the human STS cortex. In another example I will show how SNR improvements can also reduce magnetic susceptibility-related signal dropouts in brain regions such as the medial temporal lobe (MTL).
 
Relevant recent publications:
 
 
 
1) Bodurka J, Ledden PJ, van Gelderen P, Chu R, de Zwart JA,
    Morris D, Duyn JH.  Scalable multichannel MRI data
    acquisition system. Magn Reson Med 2004 Jan;51(1):165-71.
2) de Zwart JA, Ledden PJ, van Gelderen P, Bodurka J, Chu R,
    Duyn JH.  Signal-to-noise ratio and parallel imaging
    performance of a 16-channel receive-only brain coil array
 
    at 3.0 Tesla. Magn Reson Med 2004 Jan;51(1):22-6.
3) Beauchamp MS, Argall BD, Bodurka J, Duyn JH, Martin A.
    Unraveling multisensory integration: patchy organization
    within human STS multisensory cortex.
    Nature Neuroscience 2004 Nov;7(11):1190-2.
4) Bellgowan PS, Bandettini PA, van Gelderen P, Martin A,
    Bodurka J.  Improved BOLD detection in the medial
    temporal region using parallel imaging and voxel volume
    reduction. NeuroImage 2006 Feb 15;29(4):1244-51.
5) Bodurka J, Ye F, Petridou N, Murphy K, Bandettini PA.
    Mapping the MRI voxel volume in which thermal noise
    matches physiological noise--implications for fMRI. 
    NeuroImage 2007 Jan 15;34(2):542-9.
6) Murphy K, Bodurka J, Bandettini PA.
    How long to scan? The relationship between fMRI
    temporal signal to noise ratio and necessary
    scan duration.  NeuroImage 2007 Jan 15;34(2):565-74.