Podcasts /Quicktime movies of lectures and seminars produced by our team.  Please note that these files are large and will take some time to download.  If you have an iPod Video, or iTunes, we recommend downloading the iPod Video format.  Windows users can download the Quicktime Format.

Our podcasts are available as separate downloadable movie files on this
page, on iTunes , and via an RSS feed.      

• 19th May 2010 - Thorarin A Bjarnason. Quantitative T2: Software, Application, Workflows, Phase Correction - April 2010. This podcast was recorded during Thorarin Bjarnason's PhD public defense lecture. Quantitative T2 (qT2) is an emerging MRI field that utilizes the fundamental MRI T2 relaxation process and shows promise of being a non-invasive biomarker for myelin health. This thesis addresses a few limitations of qT2 understanding and analysis, including both a thorough examination of qT2 attributes that characterize more than just myelin health and improved methods of analysis. To begin, a thorough introduction of qT2 in terms of acquisition and analysis is presented, followed by a review of applications. Four studies of qT2 follow. The first study addresses qT2 analysis, presenting an open source, platform independent qT2 software package that works with data independent of MR manufacturer. A histology study follows. The next study addresses the optimal qT2 analysis method.  Finally, noise is examined. Quantitative T2 analysis is best performed on data with Gaussian distributed noise, but MRI noise is Rician distributed and simulations show that Rician noise affects the T2 distribution. A temporal phase correction method is developed and applied to in vivo human and rat qT2 data to change the noise from Rician to Gaussian prior to performing qT2 analysis.
  
  

  Format	Size
  iTunes	42MB (19 mins long)

  
  
• 15th Dec 2009 - Thorarin A Bjarnason, Tonima Ali, Mark Simpson, Cornelia Laule, J Ross Mitchell. Quantitative T2 (qT2): more than just a shade of grey - October 2009. T2 is commonly associated with different contrasts in MRI, which allows white and grey matter in brain to be visually separable as different shades of grey. By understanding the physics behind T2 we can use this relaxation mechanism to better characterize water within tissue. In this lecture I will briefly review the physics of T2 in order to highlight how it can be used as a contrast mechanism in MRI. A description of quantitative T2 (qT2) naturally follows, introducing the T2 distribution, which is a way of fully representing T2 relaxation times within an MR image. qT2 literature is reviewed, showing how different aspects of the T2 distribution reflect biology. For instance, short T2 times in the T2 distribution has been shown to correlate with myelin content, which could prove invaluable in monitoring neurodegenerative diseases such as multiple sclerosis (MS). Additionally, long T2 times in the T2 distribution highlights active lesions in MS patients. By fully characterizing the T2 relaxation process using MRI, T2 can be more than just a shade of grey.
  
  

  Format	Size
  iTunes	118MB (40 mins long)

  
  
• 14th May 2009 - Thorarin A Bjarnason, Tonima Ali, Mark Simpson, J Ross Mitchell, Cornelia Laule. Quantitative T2 with Application in Brain Cancer  - March 2009. An introduction to MRI quantitative T2 (qT2) is presented along with applications to brain cancer. We begin by describing how MRI can be sensitive different water environments within a single pixel. We review histopathological validation of qT2 for measuring myelin and present recent findings of newly discovered water environments in various brain diseases. We finish off the presentation highlighting recent applications of qT2 in cancer and discuss our recent findings and research directions.
  
  

  Format	Size
  iTunes	59MB (26 mins long)
  Quicktime	197MB

  
  

• 18th December 2008 - Thorarin A B jarnason, J Ross Mitchell. How to use AnalyzeNNLS - December 2008. This video podcast outlines how to use AnalyzeNNLS, an opensource project from ImagingInformatics.ca. AnalyzeNNLS is designed to analyze mulicompartment T2 decays from multiecho MRI experiments. This podcast provides a tutorial on how to use AnalyzeNNLS to analyze single-slice and multi-slice multiecho data.
  

  
  

  Format	Size
  iTunes	50MB (11 mins long)
  Quicktime	177MB

  
  

• 20th November 2008 - Thorarin A Bjarnason, Tonima Ali, Mark Simpson, J Ross Mitchell. Quantitative T2: Software, Workflow, Phase Correction - November 2008. This video podcast outlines 3 main areas of Thorarin Bjarnason's PhD research to improve quantitative T2 (qT2). 1) Software: Opensource qT2 analysis software is described. More recently, we have been developing a qT2 visualization tool. 2) Workflows: Different workflows have been studied for qT2 analysis and we found that non-regularized multivoxel analysis is best suited for qT2. 3) Phase Correction: Phase correcting multiecho data changes the noise-type from Rician to Gaussian. Gaussian noise is preferred for qT2 analysis algorithms.
  
  

  Format	Size
  iTunes	67MB (29 mins long)
  Quicktime	186MB

  
  

• 29th October 2008 - Thorarin A Bjarnason, Sylvia Drabycz, Mark Simpson, Ming Zhang, Tonima Ali, Mike Roberts, J Ross Mitchell. Medical Imaging Informatics - Towards Virtual Biopsy - October 2008.
  Thor presented this talk at the Welcome to New Students Seminar in SACRI. In this presentation we provide an introduction to Medical Imaging Informatics and the current research of ImagingInformatics.ca. We outline 3D visualization and tissue characterization and the roles they are playing in virtual biopsy of brain cancer tumors.