simulation tools, and techniques for kinetic model analysis. Development of these software tools is essential to accurately model the data and thereby quantify the radiotracer uptake in nuclear medicine studies. The ability to perform this task in practice has benefited from the increased availability of powerful computing resources. For example, an iterative image reconstruction algorithm with data corrections built into the system model was considered to be impractical a decade ago. Yet, this type of algorithm can now be used to generate images in a practical amount of time in both the research laboratory and the clinic (Figures 7.7 and 7.8).

Leaders in instrumentation and computational development in nuclear medicine from universities, national laboratories, and industry were solicited for commentary and analysis. Based on discussions with these experts

FIGURE 7.7 Images of mouse heart illustrate improvements due to image reconstruction: (left) filtered backprojection algorithm, (middle) iterative ordered-set expectation maximization (OSEM) algorithm, (right) OSEM with detector response modeling. Note that the OSEM reconstruction with detector response modeling has the lowest noise and the best definition of myocardial uptake. SOURCE: Courtesy of Thomas Lewellen, University of Washington.