Small Animal Imaging Resource Program @ Johns Hopkins


Quantification of Clinical PET Data

Many, if not most, of the procedures used for processing small animal studies are adapted from procedures used for processing clinical studies, or studies of non-human primates. This page is dedicated to describing those procedures. All methods use our standard software tools: Matlab, SPM, and Analyze. Matlab can be licensed at a nominal fee through SPARS, SPM is shareware http://www.fil.ion.ucl.ac.uk/spm/. Analyze is more expensive, however, it is very powerful with many add-on features. If you have any comments/questions please contact Chris Endres.


The tracers

The following tracers have been used in our lab and/or other labs at Johns Hopkins. Select a tracer below to read about the purpose of the tracer, its properties, what it has been used to investigate, and how quantitative information is extracted from PET studies.

Quantification methods

Here are detailed descriptions of the various methods that are used for quantification of PET studies. Included are links to the software in current use. Go to the tracer links on the left of this page to determine which analysis is used for any given tracer. These links describe region-of-interest (ROI) analysis. Parametric analysis is covered below.

Preprocessing steps

The following links describe in detail all the image processing that is done to prepare the data for quantitative analysis. This is the 'busy work' that will take up most of your time in evaluating PET studies.



Parametric imaging

There has been growing popularity of parametric imaging techniques that allow the analysis to expand beyond a few desired regions. With the application of SPM, effects can be detected virtually anywhere in the brain, and is especially useful when investigating systems that have a diffuse distribution in the brain. There is an art to applying SPM but there also is strong rationale for the procedures used. Here we step through the different methods for producing parametric images, and then describe the use of SPM to perform statistical evaluation of parametric images.


Parametric image generation

Statistical parametric mapping (SPM)