Tools in molecular imaging
SPECT is a well established tool in molecular imaging in man. Recently small animal microPET and microSPECT have become useful tools to perform pharmacological studies in animals. These studies provide a better understanding of the body's function in sickness and health, and allow evaluation of the efficacy and safety of new substances that may become candidates for development as new medicines for man. Today, computer studies and other alternative test methods, such as tissue culture, provide important information that helps scientists determine which substances have the potential to become new medicines. As much information as possible is derived from these methods, which have contributed significantly to the reduction of the number of animals used in recent years. Due to scientific advances and alternative methods, the total number of animals used in medicine research is falling and is now less than half what it was 20 years ago. Nevertheless, it is vital to conduct animal studies in an ethical, economical, fast and cost-effective way before physicians can justify testing new medicines in humans. It is assumed that in vivo SPECT studies will further reduce the number of animals sacrificed.
Separate CT and SPECT devices can be aligned and the images fused. Markers can help to align the objects. A further step is to go to dual modality systems. The functional SPECT data and anatomical CT data allow to determine the uptake and behaviour of the labelled compound in vivo.