HIGH-RESOLUTION IMAGE RECONSTRUCTION

The resolution of current animal PET systems is on the order of millimeter. Images with higher resolution will greatly improve our capability of studying human diseases using mouse models. For example, sub-millimeter resolution would be required in order to detect metastases or study brain function in mice. While tremendous advance has been made in detector designs, sophisticated data processing techniques are necessary to realize its full potential. We are working on several fronts to push the resolution beyond the current limit, including super-resolution with continuous bed motion, estimation of detector blurring matrix from point source data, objective assessment of image quality for detection and quantification, and error correction in reconstruction algorithms. Shown below are some example images obtained using our methods. Further readings: (Tohme_SPIE07) (Tohme_MIC07)

Top: A 3-by-3 line source phantom with 2-mm center-to-center spacing.

Middle and Bottom: The reconstructed images of the 3-by-3 phantom at 2-cm radial offset with the Monte Carlo based blurring matrix (middle) and the new estimated blurring matrix (bottom).

High-resolution PET image obtained using our method (left) compared with the image obtained using the manufacture's software (right).