Medical Physics Faculty

Jonathan Sharp

Jonathan Sharp, PhD

Associate Professor, Radiation Therapy Degree Program, Department of Oncology, University of Alberta

Physicist, Dept. of Medical Physics, CCI

B.Sc. (Natural Sciences: Cambridge, UK - 1984)
M.Sc. (Medical Physics: Aberdeen, UK - 1985)
Ph.D. (Medical Physics: London, UK - 1989)

Research Interests

Radio-Frequency Encoded Magnetic Resonance Imaging (MRI)

I am co-inventor of a novel MR imaging technology that eliminates the need for conventional imaging gradients. 'Gradient-free' imaging ('TRASE' - Transmit Array Spatial Encoding) is an entirely novel MRI approach which does away with the traditional gradient coil system, eliminating bulk, cost and much complexity. This technology has the potential to substantially reduce the cost and increase the robustness of MRI. The work was featured in Nature 'Research Highlights' in September 2013.

Real-time MRI in Radiotherapy

MRI offers superior tissue contrast and image quality than X-ray CT, but has only recently been integrated with radiotherapy treatment systems (see the website for more information). My research interest is in the MRI techniques needed for real-time control of external beam radiotherapy treatment to enable higher treatment accuracy in the presence of tumor motion.

MRI Techniques, Simulation and Image Formation

I have a long-standing interest in MRI data acquisition techniques ('pulse sequences') including the use of computer simulations. One example is a technique that I invented which retrospectively compensates for magnetic field shimming errors by combining signals from an array of detection coils.

MRI Technology

I have designed MRI control equipment (MRI consoles), two of which are currently in use running MRI research systems here in the Medical Physics division. Design of our own equipment allows us greater flexibility and scope for technological innovation than does the use of commercial systems.

Foundations of Quantum Mechanics

The topic of quantum foundations concerns efforts to find an 'interpretation' of quantum mechanics. Amongst physicists, there is remarkably little consensus on what quantum mechanics actually means, even though it is a tremendously successful and useful theory. The "Copenhagen Interpretation" of Niels Bohr is the traditional approach, but leaves much unsaid. With the development of quantum technologies, such as quantum computing and encryption, experiments are probing systems which may demand a more specific ontology. A better understanding of the causes of decoherence may be of great practical relevance for these technologies.

Selected Publications

Blasiak B, Landry J, Tyson R, Sharp JC, Iqbal U, Abulrob A, Rushford D, Matyas J,
Ponjevic D, Sutherland GR, Wolfsberger S, Tomanek B.
"Molecular Susceptibility weighted imaging of the glioma rim in a mouse model".
J Neurosci Methods. 2014 Apr 15;226:132-8. doi: 10.1016/j.jneumeth.2014.01.034. Epub 2014 Feb 10)

Sarty GE, Scott A, Turek K, Sharp JC, Tomanek B,
"Wrist MRI for the International Space Station",
65th International Astronautical Congress", Toronto, Canada. 2014.

Sharp JC, King SB, Deng Q, Volotovskyy V, Tomanek B,
"High Resolution MRI using Radio-Frequency Phase Gradients".
NMR in Biomedicine 2013 Nov;26(11):1602-7. doi: 10.1002/nbm.3023. Epub 2013 Sep 6.
This paper was featured in:
Nature ‘Research Highlights’, “A cheaper, quieter MRI machine”.
Nature 501, p.138-139 (12 September 2013). Doi:10.1038/501138e.

Deng Q, King SB, Volotovskyy V, Tomanek B, Sharp JC,
"B1 Transmit Phase Gradient Coil for Single-Axis TRASE RF Encoding",
Magn Reson Imaging. 2013 Jul;31(6):891-9. doi: 10.1016/j.mri.2013.03.017. Epub 2013 Apr 15.

Zhu X, Tomanek B, Sharp JC,
"A Pixel is an Artifact: On the Necessity of Zero-filling in Fourier Imaging".
Concepts in Magnetic Resonance Part A, Vol. 42A(2) 32–44 (2013) DOI 10.1002/cmr.a.21256

King AJ, Deng Q, Tyson R, Sharp JC, Matwiy J, Tomanek B, and Dunn JF,
"First Measurements of Non-linear Deformation of Human Posterior Cruciate Ligament over complete range of Knee Flexion Angles".
PLoS One. 2012;7(11):e48714. doi: 10.1371/journal.pone.0048714. Epub 2012 Nov 7.

Sharp JC and King SB,
"MRI using Radio-Frequency Magnetic Field Phase Gradients".
Magn. Reson. Med. 63:151-161, 2010

Sharp JC, Yin D, Bernhardt RH, Deng Q, Procca AE, Tyson RL, Lo K, Tomanek B,
"The integration of real and virtual magnetic resonance imaging experiments in a single instrument".
Rev Sci Instrum. 2009 Sep; 80(9):093709.

Weber MH, Sharp JC, Latta P, Hassard TH, Orr FW,
"Early detection and quantification of murine melanoma bone metastases with magnetic resonance imaging".
Skeletal Radiol. 2007 Jul;36(7):659-66.

(back to top)