Medical Student Research Fellowship for Summer 2009

Mentor: Ronald M. Peshock, MD
Department: Radiology
Room number: CS0.404
Mail Code: 8896
Phone number: 214-648-9605
E-mail: ron.peshock@utsouthwestern.edu
Project title: Ex-Vivo Coronary Plaque Detection by 64-Slice MDCT and 3 Tesla Cardiac Magnetic Resonance

Human subjects IRB approved project number (where applicable): None

Animal subjects IRB approved project number (where applicable): None

Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects): Basic

Brief Description of Project:

Objective: To noninvasively image and assess the morphological features of diseased human coronary arteries ex vivo using 3 Tesla magnetic resonance imaging and 64-slice multi-detector computed tomography, and to verify plaque composition with histology.

Background: Magnetic resonance imaging (MRI) has been used for noninvasive visualization of coronary vessel wall with good contrast between the coronary lumen and surrounding tissues. However, this technique has been limited by motion artifacts and low spatial resolution. Greater signal afforded by 3 Tesla MRI has the potential to overcome these limitations and characterize coronary plaque composition. Such a technique could provide new insights in the detection of vulnerable plaque. Multi-detector computed tomography (MDCT) is an established clinical technique for evaluating coronary artery disease because of its high spatial resolution, fast acquisition speed, and good delineation of non-calcified and calcified plaque.

Methods & Plan: Freshly-harvested, non-fixed cadaveric hearts from subjects with a history of coronary artery disease and/or congestive heart failure will be imaged by 3 Tesla cardiac magnetic resonance using 3-dimensional multicontrast sequences for optimal detection of the coronary lumens, vessel walls, and complex atherosclerotic plaques. Quantitative measurements will include vessel lumen and plaque areas, signal-to-noise (SNR), and contrast-to-noise (CNR) ratios. Diseased segments of the proximal left anterior segment (LAD), left circumflex artery (LCX) and the right coronary artery (RCA) will then be excised and sectioned for histological verification of plaque composition. Plaque morphological features (lipid core, fibrous cap, inflammatory cells) will be differentiated using standard staining techniques such as H&E, and Masson trichrome staining.

Previous Research Activities or Publications with Medical Students:

Maroules CD, McColl R, Khera A, and Peshock RM. Assessment and Reproducibility of Aortic Atherosclerosis MR Imaging: Impact of 3-Tesla Field Strength and Parallel Imaging. Investigative Radiology; 2008;43:656-662.

Maroules CD, McColl R, Khera A, and Peshock RM. Interstudy Reproducibility of SSFP Cine Magnetic Resonance: Impact of Magnetic Field Strength and Parallel Imaging. Journal of Magnetic Resonance Imaging, 2008; 27:1139-1145

McColl R, Lo Hao, Peshock RM. Virtual dissection of aortic lesions from MRI Proceedings of the SPIE 2004;5369:496-503.

De Lemos JA, Zirlik A, Schönbeck U, Varo N, Murphy S, Khera A, McGuire DK, Greg Stanek, MPH, Hao S. Lo, BS, Rebecca Nuzzo, BS, David A. Morrow, Ronald Peshock, MD1; Peter Libby, MD. Associations Between Soluble CD40 Ligand, Atherosclerosis Risk Factors, and Subclinical Atherosclerosis: Results from the Dallas Heart Study. Arteriosclerosis, Thrombosis and vascular Biology 2005;25:2192-6.

Amit Patel. Correction of EBCT images for differences in attenuation.

Amit Patel. Computer Aided Diagnosis of LV Wall Focal Hypertrophy.