PRESENTATIONS (2)
Student presentation:
“Attenuation Correction in Pinhole Cardiac SPECT using Data Consistency Conditions”
In Single Photon Emission Computed Tomography (SPECT) imaging, accurate photon-attenuation correction is vitally important to provide accurate and quantitative radionuclide activity distributions. Specialized cardiac SPECT cameras offer improved sensitivity and resolution, but most widely available cardiac-specific SPECT systems do not include an onboard CT scanner to generate an attenuation map for attenuation correction. Thus, attenuation maps must be generated from a separately acquired CT scan and then be manually aligned with the SPECT image. Data Consistency Conditions
(DCCs) provide a mathematical framework that describes the redundancies between one attenuated emission view and another. Initial work has shown that it may be feasible to use these DCCs to register the externally acquired attenuation map with the emission data and thereby avoid the need
for manual alignment. A challenge with this approach is that it assumes
all the activity sources responsible for the emission images are within a convex homogeneous region of the patient. This assumption is frequently violated in cardiac imaging due to background uptake in the liver and intestines. We hypothesize that using the temporal characteristics of an ECG-gated dataset will overcome this challenge. In this presentation, I will discuss the current DCC approach, as well as how I will extend the approach to account for extra-cardiac activity.
By Taylon Clark
Department of Physics, Carleton University
Supervisor: Dr. Glenn Wells, University of Ottawa Heart Institute
Member presentation:
“Should we report Dmed or Dwater in photon beam radiotherapy?”
Historically there have been many misleading and/or confusing statements in the literature about whether to report the dose to the medium or the dose to water. The talk outlines what the underlying problems are and explores various concepts making use of Monte Carlo calculations I have done to elucidate the issues.
By Dr. David Rogers
Department of Physics, Carleton University