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William Paul Segars

Professor in Radiology
Radiology
Box 2731 Med Ctr, 2424 Erwin Road, Durham, NC 27710
Hock Plaza Suite 302, 2424 Erwin Road, Durham, NC 27705

Overview


Our current research involves the use of computer-generated phantoms and simulation techniques to investigate and optimize medical imaging systems and methods. Medical imaging simulation involves virtual experiments carried out entirely on the computer using computational models for the patients as well as the imaging devices. Simulation is a powerful tool for characterizing, evaluating, and optimizing medical imaging systems. A vital aspect of simulation is to have realistic models of the subject's anatomy as well as accurate models for the physics of the imaging process. Without this, the results of the simulation may not be indicative of what would occur in actual clinical studies and would, therefore, have limited practical value. We are leading the development of realistic simulation tools for use toward human and small animal imaging research.

These tools have a wide variety of applications in many different imaging modalities to investigate the effects of anatomical, physiological, physical, and instrumentational factors on medical imaging and to research new image acquisition strategies, image processing and reconstruction methods, and image visualization and interpretation techniques. We are currently applying them to the field of x-ray CT. The motivation for this work is the lack of sufficiently rigorous methods for optimizing the image quality and radiation dose in x-ray CT to the clinical needs of a given procedure. The danger of unnecessary radiation exposure from CT applications, especially for pediatrics, is just now being addressed. Optimization is essential in order for new and emerging CT applications to be truly useful and not represent a danger to the patient. Given the relatively high radiation doses required of current CT systems, thorough optimization is unlikely to ever be done in live patients. It would be prohibitively expensive to fabricate physical phantoms to simulate a realistic range of patient sizes and clinical needs especially when physiologic motion needs to be considered. The only practical approach to the optimization problem is through the use of realistic computer simulation tools developed in our work.

Current Appointments & Affiliations


Professor in Radiology · 2024 - Present Radiology, Clinical Science Departments

In the News


Published November 16, 2022
Artemis Launches With Two Duke Experiments
Published September 7, 2022
Meet Helga and Zohar, Duke's Space Pioneers

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Recent Publications


XCAT 3.0: A comprehensive library of personalized digital twins derived from CT scans.

Journal Article Med Image Anal · July 2025 Virtual Imaging Trials (VIT) offer a cost-effective and scalable approach for evaluating medical imaging technologies. Computational phantoms, which mimic real patient anatomy and physiology, play a central role in VITs. However, the current libraries of c ... Full text Link to item Cite

Volumetric soft tissue perfusion assessment on a region basis from x-ray angiography images: Motion compensation.

Journal Article Medical physics · June 2025 BackgroundAssessing the soft tissue perfusion quantitatively in interventional suites before, during, and after interventional procedures is desired. The method, if possible, has to assess the perfusion volumetrically and quantitatively, be robust ... Full text Cite

AAPM Truth-based CT (TrueCT) reconstruction grand challenge.

Journal Article Med Phys · April 2025 BACKGROUND: This Special Report summarizes the 2022, AAPM grand challenge on Truth-based CT image reconstruction. PURPOSE: To provide an objective framework for evaluating CT reconstruction methods using virtual imaging resources consisting of a library of ... Full text Link to item Cite
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Recent Grants


Accuracy and Precision in CT Quantification of COPD Through Virtual Imaging Trials

ResearchInvestigator · Awarded by National Heart, Lung, and Blood Institute · 2021 - 2026

eXtended Modular ANthropomorphic (XMAN) phantom for Imaging and Treatment Optimization in Radiotherapy

ResearchPrincipal Investigator · Awarded by University of Maryland, Baltimore · 2022 - 2026

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Education, Training & Certifications


University of North Carolina, Chapel Hill · 2001 Ph.D.

External Links


Google Scholar