Background
Magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and optical imaging have become useful and standard tools for researchers to non-invasively monitor physiological, anatomical, and molecular events in living animals. In vivo imaging provides important information into disease development, therapeutic efficacy of an external agent such as a drug or a gene, and the fate of such agent in toxicology and dosage studies. These experiments generally require repetitive imaging of the same animal. Further, the same animal may be imaged under different platforms since each provides a different kind of information. For example, CT and MRI provide anatomic and morphological information but little about biological information that PET and SPECT provide. Repetitive imaging under the same platform and imaging under different platforms both share a common requirement: the precise positioning of the animal. Positioning is important for comparing results between control and experimental data and also data from the different imaging platforms. As a result, there is a need for a device that enables the precise positioning of an animal subject in repetitive imaging and imaging under different platforms. Such a device should also address some of the important features for in vivo imaging of small laboratory animals such as heating, anesthesia support, hypothermia prevention, and sterile environment for immuno-compromised animals.
Innovation
UCLA researchers have invented and prototyped a device that enables reproducible positioning of small laboratory animals (rats and mice). The invention provides an imaging chamber that enables the subject to be imaged in the same fixed position over different time period and for the same animal to be imaged in that same fixed position under different imaging platforms so that the image can be easily compared or overlaid. The system offers the following important benefits: 1) Reproducible animal positioning for longitudinal studies with an average location difference of 790 micro meters; 2) Fixed position between multiple modalities (hardware image registration) with an location difference of 82 micro meters; 3) Optimal positioning within imaging devices ensures whole animal is within field of view. The invention also provides the following additional features that are invaluable to researchers: 1) Sterile, pathogen free chamber for immuno-compromised animal subjects; 2) Gas anesthesia support; 3) Hypothermia prevention, continuous temperature monitoring to within 0.1 degree centrigrade; and, 4) Chamber and gas anesthesia minimize the possibility for motion and position artifacts
Applications
Research, preclinical, and veterinary studies using PET/CT/MRI/Optical
Advantages
- Ease of use for high imaging throughput;
- Compatible with PET/CT/MRI/ Optical;
- The device provides for a sustainable product line since it needs to be replaced every one to two years.
State Of Development
The final prototype was machined in August 2003 and successfully tested for mouse with accompanying data for PET and CT. The researchers are currently developing a modification of the invention, which will be also effective for use with optical imaging.