Diffusion Weighted MRI and Magnetic Resonance Spectroscopy to Differentiate Radiation Necrosis and Recurrent Disease in Gliomas

 

This web page is a summary of the bimonthly presentations we have been
having that detail the progress we are making toward the goal
listed in the title above. 


The first of our bimonthly meetings took place on 12/17/07.  


At that meeting, there were three presentations.  The first was given by Naren
Vijayakumar and it was about how to register two DWMRI images using Mutual 
Information (MI). A copy of those Powerpoint slides can be obtained 
 here .

The second presentation was given by Tim McDaniels and it was about how to 
calculate ADC values for the patients enrolled in our protocol.  In addition,
he described an algorithm to insure that the MRI images for which ADC values
are determined 'matched' one another.  A copy of those Powerpoint slides can
be obtained  here .

The third presentation was given by Tom Chong and it was about Magnetic
Resonance Spectroscopy, and how he has made the data available on the web.  A 
copy of those Power point slides can be obtained
 here . 


The second of our meetings took place on 1/7/08. 
 

At that meeting, there were two presentations.  The first was given by Tim 
McDaniels.  He discussed the variation in the ADC values calculated for 
different patients in the protocol.  In addition, he plotted the variation in 
intensity of non-diffusion weighted MRI images.  A copy of those Powerpoint 
slides can be obtainted  here .

The second presenation was given by Tom Chong, and it discussed a recent
European initiative called INTERPRET.  This initiative is designed to
standardize different aspects of Magnetic Resonance Spectroscopy, by 
combining the results of a number of different participating institutions.
In addition, he discussed water suppression in MRS, and how this can affect
different spectra.  A copy of those slided can be obtained
 here . 


The third of our meetings took place today, 1/25/08. 


At this meeting, there were four presentations.  The first was given by Lars 
Ewell.  He discussed the spatial variation of the Cho/NAA ratio in the first 
of our protocol patients.  A copy of those slides can be seen  here .

The second presentation was given by Tom Chong.  He discussed how the INTERPRET
software can be utilized in identifying meningiomas.  In addition, he also
discussed the spatial variation in the Cho/NAA ratios of our first two 
patients.  He developed a method to correlate Cho/NAA ratios from inferior to
superior slices.  The three parts of his presentation can be viewed
 here_one ,  here_two ,  here_three . 

The third presentation was given by Tim McDaniels.  He compared ADC 
coefficients from two different patients.  He hypothesized that a decrease
in signal intensity is correlated with increased deviation in ADC values.
A copy of his slides can be found  here .

The fourth presenation was given by Naren Vijayakumar.  He compared different
registration methods.  He found that Mutual Information (MI) and Cost Function
(CF) methods worked well to reproduce known tranlations, only MI reproduced
rotations.  A copy of his slides can be found  here . 


The fourth of our meetings took place on 2/8/08. 


The first presentation was given by Lars Ewell.  He discussed some of the 
differences between the FLAIR images on which lesions are contoured, and the
DWMRI images from which ADC values are determined.  A copy of his slides can
be seen  here .

The second presentation was given by Tim McDaniels.  He discussed how to
combine ADCs across slices to obtain an ADC for an entire lesion.  A copy of
his slides can be found  here .

The third presentation was given by Naren Vijayakumar.  He discussed how using
Mutual Information (MI) as a registration method can be utilized to compare
Echo Planar DWMRI with Radial Diffusion DWMRI.  A copy of those slides can
be found  here .

The fourth presentation was given by Tom Chong.  He discussed applying the
INTERPRET criteria to the patients enrolled in our protocol.  One thing that
was discussed was the rigorous criteria used to 'filter' the data that gets
into the INTERPRET database.  We indicated that this has the potential to
bias the data, making comparisons difficult.  In addition, he showed
a plot of our most recent patient, and we were encouraged that her scans 
appeared to contain a number of valid voxels.  A copy of his slides can
be obtained  here_one , here_two .

The fifth of our meetings took place on 2/29/08. 


The first presentation was given by Naren Vijayakumar.  He gave a presentation
titled 'Improving Registration Accuracy'.  In this talk, he discussed 
increasing the accuracy of image registration using 'K-means clustering'.  
A copy of this slides can be found 
 here .

The second presentation was given by Lars Ewell.  He talked about a manuscript
that is based on the results of the radial diffusion and mutual information
registration.  A copy of the slides can be found 
 here .

The third presentation was given by Thomas Chong.  He discussed the most recent
patient that has been enrolled, and the sensitivity of the data to peak
locations.  A copy of his slides can be found 
 here .

The fourth presentation was given by Tim McDaniels.  He reviewed some of the
recent ADC calculations, and discussed a draft abstract to the upcoming
American Association of Physicists in Medicine (AAPM) abstract.  A copy of his
slides can be found  here 

The sixth of our meetings took place on 3/14/08. 


The first presentation was given by Naren Vijayakumar.  He clarified how
mutual information can be used to register two images.  A copy of his slides
can be found  here 

The second presentation was given by Tim McDaniels.  He discussed the variation
in ADC values from different protocol patients.  A copy of this slides can be
found  here 

The third presentation was given by Tom Chong.  He discussed some recent
MRS scans.  A copy of this slides can be found 
 here 

The seventh of our meetings was held on 3/28/08. 


The first presentation was given by Tim McDaniels.  He showed data that 
indicated a drop in pixel intensity around slice number ten.  In more inferior
positions, this drop correlated to a rise in ADC values.  A copy of his slide
can be obtained  here .

The second presentation was given by Tom Chong.  He discussed some recent 
scans of a brain metabolite phantom.  A copy of his slides can be seen 
 here 

The eighth of our meetings was held on 4/11/08. 


The first presentation was given by Tim McDaniels.  He performed a bi-linear
fit to ADC values.  A copy of his slides can be found
 here  


The second presentation was given by Tom Chong.  He discussed comparision of
single voxel spectroscopy with multi voxel spectroscopy.  A copy of his
slides can be seen  here  


The ninth of our meetings was held on 4/25/08. 


The first presentation was given by Lars Ewell.  He discussed the recent
manuscript that was submitted to Magnetic Resonance in Medicine.  In addition,
he discussed changing the MRS scan parameters to obtain more usable data.
A copy of his slides can be seen  here  


The second presentation was given by Tim McDaniels.  He gave a summary of the
number of ADC calculations for all of the enrolled patients.  He also discussed
some issues involved with individual patients.   A copy of his slides can be
seen  here  


The third presenation was given by Naren Vijayakumar.  He discussed ways to 
improve the image registration metric of mutual information.  A copy of his 
slides can be seen  here  



The tenth of our meetings was held on 5/9/08. 


The only presentation was given by Tim McDaniels.  He summarized the temporal
dependence of the ADC lesion values of the enrolled patients.  In addition,
he discussed his upcoming AAMP presentation.  A copy of his slides can be
seen  here  


The eleventh of our meetings was held on 5/23/08. 


The only presentation was given by Lars Ewell.  He gave an overall summary of
past research results, mainly for the benefit of new group member, Amarjeet
Bullar .  A copy of his slides can be seen  here  


The twelveth of our meetings was held on 6/6/08. 


Lars Ewell presented an update of the imaging protocol at this meeting.
A copy of this slides can be seen  here  


Tim McDaniels presented some slides indicating how to transcribe contours
to calculate ADCs.  A copy of his slides can be seen  here  


The thirteenth of our meetings was held on 6/20/08. 


Lars Ewell presented some slides he was preparing for a faculty update.
A copy of those slides can be obtained  here  


The fourteenth of our meetings was held on 7/7/08. 


Amarjeet Bhullar presented some slides about a recent MRS study for the fifth
scan of our fifth protocol patient.  A copy of those slides can be obtained
 here  


Tim McDaniels presented some slides about ADC calculations for this same
protocol patient.  A copy of those slides can be obtained 
 here  


The fifteenth of our meetings was held on 7/22/08. 


Amarjeet Bhullar presented some slides about MRS and how to analytically
fit metabolite peaks.  A copy of his slides can be obtained 
 here  


Tim McDaniels presented the poster he will present at this years AAPM
meeting in Houston on 7/27/08.  A copy of the poster can be seen
 here  


Lars Ewell presented the poster he will present at this years SANTRO
meeting in Beijing on 8/28/08.  A copy of the poster can be seen
 here  


The sixteenth of our meetings was held on 8/8/08. 


Amarjeet Bhullar presented some slides on the accuracy with which
Functool calculates metabolite ratios.  A copy of his slides can be
seen 
 here  



The seventeenth of our meetings was held on 8/22/08. 


Lars Ewell presented the start of a manuscript, based on the work that
Tim McDaniel and him presented at the recent AAPM meeting.  A copy of the
slides can be seen
 here  


Amarjeet Bhullar presented some slides comparing metabolite ratio calculations.
A copy of his slides can be seen
 here  


The eighteenth of our meetings was held on 9/12/08. 


Tim McDaniels presented some work about uncertainty in ADC calculations related
to the manuscript under prepartation.  He also discussed an error, uncovered
by Amarajeet Bhullar, that changed some of the prior calculations.  A copy
of his slides can be seen 
 here  


Amarjeet Bhullar presented some slides about uncertainty in ADC calculations,
related to the manuscript.  A copy of his slides can be seen
 here  


The nineteenth of our meetings was held on 9/26/08. 


Amarjeet Bhullar reviewed some recent MRS protocol scans.  A copy of this
slides can be seen 
 here  


Tim McDaniels discussed uncertainty related to calculation of Apparent 
Diffusion Coefficients (ADCs).  A copy of this slides can be seen
 here  


Lars Ewell discussed recent developments in the manuscript.  A copy of his
slides can be seen  here  


The twentieth of our meetings was held on 10/10/08. 


Amarjeet Bhullar discussed how different background levels can affect
metabolite ratios, as measured by MRS.  A copy of this slides can
be seen 
 here  


Naren Vijayakumar presented some work relating how combining gradient
information and clustering can help in image registration.  A copy
of this slides can be seen
 here  


Tim McDaniels talked about how to account for uncertainty in Apparent
Diffusion Coefficient (ADC) calculations.  A copy of this slides can 
be seen
 here  


The twentyfirst of our meetings was held on 10/24/08. 


Tim McDaniels presented some work on uncertainty calculations.  A copy of
this slides can be seen
 here  


Lars Ewell discussed a related manuscript in preparation.  More information
about this manuscript can be seen  here  



The twentysecond of our meetings was held on 11/14/08. 


Lars Ewell discussed a related manuscript in preparation.  More information
about this manuscript can be seen  here  



Amarjeet Bhullar discussed the recent manuscript, and how a weighted least 
squares fit should be done.  More information about this work can be seen
 here  


The twentythird of our meetings was held on 12/5/08. 


Lars Ewell discussed the variation of pixel intensity, with lesion location.
A copy of his slides can be seen
 here  


Amarjeet Bhullar discussed the difference between fitting MRS peaks with
a Lorentzian curve vs. a Gaussian curve. A copy of his slides can be seen
 here  


Tim McDaniels discussed how total uncertainties in the calculation of
apparent diffusion coeficients add up  
 here . 


The twentyfourth of our meetings was held on 12/19/08. 


Tim McDaniels discussed how the lesion placement uncertainty
affects calculated ADC values.  A copy of his slides can be
seen  here . 


Lars Ewell talked about the uncertainty manuscript in preparation.  Information
about the paper can be seen  here . 


The twentyfifth of our meetings was held on 1/23/09.

Amarjett Bhullar discussed recent phantom MRS measurments, and how added
spectra compare with individual sums.  A copy of his slides can be seen
 here . 


The twentysixth of our meetings was held on 2/13/09

Amarjeet Bhullar discussed how the MRS signal from a 7x7 grid compared with
the signal from a 15x15 grid.  A copy of his slides can be seen
 here . 


The twentyseventh of our meetings was held on 3/13/09

Lars Ewell discussed a recent grant application that he has been working on.
There is information about it that can be seen
 here. 


Amarjeet Bhullar discussed some recent MRS analysis.  A copy of his slides
can be seen  here. 


Joshua Kim reported on some ADC measurements.  A copy of his slides can
be seen  here. 


If there are any questions about the above, or difficulty with the links,
I ask that you please email me .
 


The 28th of our meetings was held on 3/27/09.

Lars Ewell discussed the grant application and the RECIST guidelines.
There is information about it that can be seen
 here. 


Joshua Kim showed some slides indicating how ADC varies with position.  A copy
of his slides can be seen  here. 


Amarjeet Bhullar discussed the MRS spectra of a recent patient.  A copy of his
slides can be seen  here. 


The 29th of our meetings was held on 4/3/09.

Lars Ewell discussed the NIH grant application.
There is information about it that can be seen
 here. 


Amarjeet Bhullar discussed the time dependence of the MRS spectra of a 
recent patient.  A copy of his slides can be seen  
here. 


We held a meeting this past Friday, 6/12/09.

The newest member of the group, Taylor Gillie, discussed ADCs and
the difference between Echo Planar (EP) and Radial Diffusion (RD).
A copy of her slides can be found  here. 


Amajeet Bhullar discussed the most recent MRS scan, as well as a summary
of his background calculation.  A copy of his slides can be found
 here. 


Joshua Kim discussed some recent ADC calculations, and the functional 
dependence of the ADC on position.  A copy of his slides can be found
 here.