Radiology Research - Faculty

Mark Williams, Ph.D.

Associate Professor of Radiology

Box 801339
University of Virginia
Charlottesville, VA 22908

e-mail:  mbw7a@Virginia.edu

Office:  434-982-4422
Labs: 434-243-2687 / 924-2843

 

 MarkWilliams

Education:

Ph.D., Physics, 1990, University of Virginia

M.S., Physics, 1983, Wake Forest University

B.C., Physics, 1977, Grinnell College

Research Interest:

The general area of research in my lab is the design, development and optimization of medical imaging technologies. The following projects are underway:

       1) Dual Modality Breast Imaging: In co-operation with Brandeis University and Thomas Jefferson National Accelerator Facility, we have developed an integrated imaging system that combines the sensitivity of digital mammography with the specificity of scintimammography in a single compact, upright unit. The imaging system functions by obtaining mirror-image x-ray transmission and gamma emission images concurrently with the breast in a single configuration. Co-registration then correlates the gamma and x-ray images to within a fraction of a pixel. 

       2) Molecular Imaging System for Small Animal Research: We are developing an imaging system that permits simultaneous acquisition of high resolution functional (nuclear medicine) and structural (digital x-ray) images of mice and rats. The resulting fused image correlates the radiotracer distribution with the morphological information provided by the x-ray data. The system is being utilized for several mouse and rat studies in gene expression imaging, radiation oncology and diagnostic radiology. 

       3) Multiple View Dual Modality Breast Imager: This system is a second generation of the Dual Modality breast imaging system described above. Here the breast is held under mild compression on a breast support structure that is independent of the detectors and the gantry arm. Multiple view imaging makes it possible to obtain three-dimensional lesion localization with this system. We are trying to apply the three-dimensional lesion location to obtain an improved estimate of the lesion to background concentration. 

       4) Integrated CT-SPECT System for Small Animal Imaging: We are developing a scanner for simultaneous acquisition of x-ray computed tomography (CT) and single photon emission tomography (SPECT) images of small animals such as mice and rats. The scanner uses a cone beam geometry for both the x-ray transmission and gamma emission projections by using an area x-ray detector and pinhole collimator, respectively. The CT and SPECT data sets are overlaid to form a coregistered structural-functional 3D image. 
 

Current Projects:

Molecular imaging system for small animal research:  We are developing a tomographic imaging system that permits simultaneous acquisition of high resolution functional (SPECT) and structural (x-ray CT) images from mice and rats.  The resulting fused image correlates the radiotracer distribution with the morphological information provided by the x-ray data. A similar 2-dimensional system is being routinely utilized as a component of the Small Animal Multimodality Imaging Center for mouse and at studies in gene expression imaging, radiation oncology and diagnostic radiology.

Recent & Representative Publications
  

M. B. Williams, M. J. Moré, D. Narayanan, S. Majewski, A. G. Weisenberger, R. Wojcik, M. Stanton, W. Phillips, A. Stewart, “Combined Structural and Functional Imaging of the breast”, Technology in Cancer Research and Treatment, vol. 1, no. 1, pp. 39-42, February 2002. 

Mark B. Williams, Mitali J. Moré, Deepa Narayanan, Stan Majewski, Ben Welch, and Douglas A. Kieper, “Phantom Study of Radiotracer Concentration Quantification in Breast Scintigraphy”, IEEE Transactions on Nuclear Science, 2003. 

Mark B. Williams, Deepa Narayanan, Mitali J. Moré, Patricia J. Goodale, Stan Majewski, Douglas Kieper, “Analysis of Position-Dependent Compton Scatter in Scintimammography With Mild Compression”, IEEE Nuclear Science Symposium Conference Record, 2002. 

Mitali J. Moré, Deepa Narayanan, Patricia J. Goodale, Stan Majewski, Benjamin Welch, Randolph Wojcik and Mark B. Williams, “X-ray Stereotactic Lesion Localization in Conjunction with Dedicated Scintimammography”, IEEE Nuclear Science Symposium Conference Record, 2002. 

Mark B. Williams, Alexander V. Stolin and Bijoy K. Kundu, “Investigation of Spatial Resolution and Efficacy using Pinholes with small Pinhole Angle”, IEEE Nuclear Science Symposium Conference Record, 2002. 

Mark B. Williams , Alexander V. Stolin, Bijoy K. Kundu, Yibin Zheng and Heng Li, “Investigation of Square Cross-Section Apertures for Small Animal Pinhole SPECT”, submitted to International Conference. Resolution Molecular Imaging in Small Animals (AMI/HiRes), September 21-24, Madrid, Spain, (2003). 


  
  
  
  
  
   
  
  
  
  
   

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