Photon Migration Imaging Toolbox

Diffuse optical tomography [DOT] is an emerging technique for non-invasive medical imaging. Using optical fibers, light is directed into biological tissue. As the light travels through the tissue it is scattered many times and exits as a diffuse photon fluence. The exiting photons are collected and photo-detectors record the intensity. The measured data can then be interpreted to provide information about the optical scattering and absorption of the region probed by the photons. If multiple overlapping measurements are available, tomographic reconstruction techniques can be used to produce three-dimensional images within the region of interest. In addition, by operating at multiple wavelengths within the tissue, the optical absorption coefficients can be related back to the local concentration of oxy- and deoxy-hemoglobin (or, equivalently, to the total hemoglobin concentration and oxygen saturation). These quantities, in turn, indicate local tissue metabolism.

The Photon Migration Imaging (PMI) toolbox implements numerous algorithms for performing the forward and inverse calculations associated with diffusive optical imaging. The toolbox is implemented in Matlab and is (for the most part) platform independent.

Copies of the PMI Toolbox can be downloaded from the PMI Toolbox Website. Installation instructions and sample code can be downloaded from the same place. We also maintain a listserver for discussions between users of the PMI Toolbox and announcements relating to the toolbox. To subscribe to the PMI listserver, send mail to majordomo@nmr.mgh.harvard.edu with the text subscribe pmi email_address in the body of the email where email_address is the email address you wish to have the listserve emails sent to.

Documentation

Note: this documentation uses XHTML and MathML in places to specify various mathematical expressions. While most modern browsers support MathML, they may need additional plug-ins or fonts in order to correctly render the equations. In particular, both Mozilla and Microsoft Internet Explorer will likely need additional files to correctly display mathematical expressions.