The Siemens Focus 120 MicroPET is a high-resolution, small animal PET scanner that combines high spatial resolution (<1.3 mm) and high sensitivity (>7%) with a bore size (12 cm diameter and 7.6 axial length) that is optimized for imaging mice and rats. Among commercially available radioactive agents, we are routinely imaging with 18F 2-fluoro-2-deoxy-D-glucose (FDG) and 18F sodium fluoride. We have also carried out some microPET studies with 18F fluorothymidine (FLT) provided by the Division of Nuclear Medicine at Massachusetts General Hospital; we have validated the synthesis of 18F FHBG and have carried out preliminary studies with this tracer; and we are developing a new 18F-labeled αvβ3 imaging agent.
The host computer for the Focus 120 is a dual-processor 3.2 GHz Pentium IV workstation with 3 GB of RAM and a 400 GB RAID storage device and a 19-inch high-resolution flat-panel display.
The Siemens microCAT II is a high-resolution (27 microns in standard mode and 15 microns in high-resolution mode) CT scanner designed specifically for imaging small animals such as mice and rats. The radiation detector is configurable such that, for mice, the transaxial field of view is 5.4 cm and the axial field of view is 8 cm; whereas, for rats, the transaxial field of view is 8 cm and the axial field of view is 5.4 cm. We have utilized microCT for tumor imaging, for anatomical correlation for microPET studies, and for ex vivo imaging (e.g., structural analysis of porcine cardiac valves).
The host computer for the microCAT II is a dual 3.2 GHz processor workstation with 2 GB of RAM and a 600 GB RAID storage system and a high resolution 20.0 inch flat-panel display. A separate processing system is used for real-time reconstruction. This system uses two processors to generate 512 x 512 x 768 voxel image volumes in real time during a scan.
The laboratory is equipped with a VisualSonics Vevo 770 small animal ultrasound system. This is a high-resolution instrument (30 microns) that can also image at high speed (up to 100 frames per second). It is capable of imaging in 3D mode as well as M mode, and can also provide pulsed wave Doppler imaging. The device is equipped with two transducers (25 and 40 MHz) and the Vevo Integrated Rail System, which facilitates alignment of the mouse and the probe as well as image-guided injection, when necessary. The table is heated and includes sensor pads for monitoring the animal during examination. The system is routinely used for cardiac imaging in small animals.
Large-animal fluoroscopy is available using an ADC/XRE Unicath SP single-plane cardiovascular digital angiography unit with a high-resolution fluoroscopy tube, an advanced image intensifier with full-frame zoom, and an image analysis workstation.
The Faxitron MX-20 Specimen Radiograph System provides high-resolution x-ray images of mice and small rats (the system includes a gas anesthesia system) as well the ability to obtain radiographic images of excised tissue samples. The x-ray tube can operate at voltages ranging from 10 to 35 kVp with a maximum tube current of 300 µA. The focal spot is 20 µm allowing for very high spatial resolution. The system is mounted on a cart and can be moved around the laboratory as necessary.