Wojtek Zbijewski

Last updated
Wojciech (Wojtek) Zbijewski
Alma mater University of Warsaw
Utrecht University
Scientific career
Institutions Johns Hopkins University
Johns Hopkins School of Medicine
Thesis Model-based image reconstruction in X-ray computed tomography  (2006)
Doctoral advisor Freek J. Beekman
Website http://carnegie.jhu.edu/index.php/people/

Wojciech (Wojtek) Zbijewski is an American biomedical engineering and medical physics working in the fields of Computed tomography (CT), Cone beam computed tomography (CBCT), image reconstruction in CT, and applications of CT and CBCT in orthopedics. He is faculty at the Department of Biomedical Engineering at Johns Hopkins School of Medicine.

Contents

Biography

Zbijewski did his undergraduate studies at Dept. of Physics at the University of Warsaw where he received his Master of Science degree in the Laboratory of Biomedical Physics. He then joined the Image Sciences Institute at Utrecht University, where he obtained a doctoral degree with a thesis on statistical image reconstruction and artifact correction in Computed tomography. [1]

After several years in industry, Zbijewski joined Johns Hopkins School of Medicine where he is now faculty in Department of Biomedical Engineering.

Work

Zbijewski research is focused on Computed tomography system optimization, algorithm development, and clinical applications, including contributions in Iterative reconstruction, [2] artifact correction, [3] weight-bearing CBCT of the extremities, [4] and new CBCT systems and algorithms for high-resolution quantitative imaging of bone health, [5]

Related Research Articles

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A computed tomography scan is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers or radiology technologists.

<span class="mw-page-title-main">Tomography</span> Imaging by sections or sectioning using a penetrative wave

Tomography is imaging by sections or sectioning that uses any kind of penetrating wave. The method is used in radiology, archaeology, biology, atmospheric science, geophysics, oceanography, plasma physics, materials science, cosmochemistry, astrophysics, quantum information, and other areas of science. The word tomography is derived from Ancient Greek τόμος tomos, "slice, section" and γράφω graphō, "to write" or, in this context as well, "to describe." A device used in tomography is called a tomograph, while the image produced is a tomogram.

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<span class="mw-page-title-main">Tomographic reconstruction</span> Estimate object properties from a finite number of projections

Tomographic reconstruction is a type of multidimensional inverse problem where the challenge is to yield an estimate of a specific system from a finite number of projections. The mathematical basis for tomographic imaging was laid down by Johann Radon. A notable example of applications is the reconstruction of computed tomography (CT) where cross-sectional images of patients are obtained in non-invasive manner. Recent developments have seen the Radon transform and its inverse used for tasks related to realistic object insertion required for testing and evaluating computed tomography use in airport security.

<span class="mw-page-title-main">Iterative reconstruction</span>

Iterative reconstruction refers to iterative algorithms used to reconstruct 2D and 3D images in certain imaging techniques. For example, in computed tomography an image must be reconstructed from projections of an object. Here, iterative reconstruction techniques are usually a better, but computationally more expensive alternative to the common filtered back projection (FBP) method, which directly calculates the image in a single reconstruction step. In recent research works, scientists have shown that extremely fast computations and massive parallelism is possible for iterative reconstruction, which makes iterative reconstruction practical for commercialization.

<span class="mw-page-title-main">X-ray microtomography</span> X-ray 3D imaging method

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David A. Jaffray is a Canadian medical physicist and Senior Scientist in the Division of Biophysics and Bioimaging at the Ontario Cancer Institute. He is also a professor and Vice Chair in the University of Toronto's Department of Radiation Oncology. He is the inventor, together with John Wong and Jeffrey Siewerdsen, of on-line volumetric kv-imaging guidance system for radiation therapy.

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<span class="mw-page-title-main">4DCT</span>

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<span class="mw-page-title-main">Operation of computed tomography</span>

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References

  1. Zbijewski, Wojciech (2006). Model-based image reconstruction in X-ray computed tomography (PhD thesis). Utrecht University. hdl:1874/9678.
  2. Zbijewski, W.; Beekman, F.J. (2004). "Characterization and suppression of edge and aliasing artefacts in iterative x-ray CT reconstruction". Phys Med Biol. 49 (1): 145–157. Bibcode:2004PMB....49..145Z. doi:10.1088/0031-9155/49/1/010. PMID   14971778. S2CID   250797868.
  3. Zbijewski, W.; Beekman, F.J. (2006). "Efficient Monte Carlo based scatter artifact reduction in cone-beam micro-CT". IEEE Transactions on Medical Imaging. 25 (7): 817–827. doi:10.1109/tmi.2006.872328. PMID   16827483. S2CID   22319246.
  4. Zbijewski, W.; De Jean, P.; Prakash, P.; Ding, Y.; Stayman, J.W.; Packard, N.; Senn, R.; Yang, D.; Yorkston, J.; Machado, A.; Carrino, J.A.; Siewerdsen, J.H. (2011). "A dedicated cone-beam CT system for musculoskeletal extremities imaging: design, optimization, and initial performance characterization". Medical Physics. 38 (8): 4700–47131. Bibcode:2011MedPh..38.4700Z. doi:10.1118/1.3611039. PMC   3172864 . PMID   21928644.
  5. Cao, Q.; Sisniega, A.; Brehler, M.; Stayman, J.W.; Yorkston, J.; Siewerdsen, J.H.; Zbijewski, W. (2017). "Modeling and Evaluation of a High-Resolution CMOS Detector for Cone-Beam CT of the Extremities". Medical Physics. 45 (1): 114–130. doi:10.1002/mp.12654. PMC   5774240 . PMID   29095489.