The Center includes two vascular/interventional radiology suites with adjoining darkrooms, a medical device development workshop, a computerized tomography (CT) area, a magnetic resonance imaging (MRI) system, an in vivo microscopy laboratory, two cabinet microradiography x-ray systems and a metabolic chemistry laboratory. In addition, a volume CT scanner developed in collaboration with General Electric was installed in the Center in 2003.
Each of the two vascular/interventional radiology suites contain a high frequency x-ray generator and movable ceiling-mounted x-ray tube; x-ray film changer and digital programmer for radiography and angiography; a portable C-arm fluoroscopy unit with spot film, roadmapping, real-time subtraction, last image hold, monitor image storage, cine (15 frames/second) capabilities and a hard copy imaging camera; and a microradiographic unit (Faxitron cabinet x-ray system). Two ultrasound imaging systems (ATL and Toshiba) with color flow Doppler are also available.
Transcatheter Medical Device Development Workshop
The transcatheter medical device development workshop is equipped for fabrication and bench testing of prototypic transcatheter devices and delivery systems. Since these medical devices are placed in the body percutaneously via catheters, they obviate the need for general anesthesia and major surgery. The devices developed in this laboratory are constructed primarily from nitinol (nickel-titanium alloy), stainless steel and various fabric materials.
The Center’s computerized tomography (CT) area contains a General Electric HiSpeed Advantage helical scanner and an automated contrast injector system. The helical scanner allows for faster data acquisition and higher resolution images than would be obtainable with conventional CT. The fast data acquisition and high resolution are well suited to 3-D reconstruction of complex anatomy. The x-ray tube voltage and current can be adjusted to produce optimal image quality.
MRI is a tomographic imaging modality that is known for high spatial resolution and exquisite soft tissue contrast. MRI can also be used to acquire spectroscopy or spectroscopic imaging data as well. A Bruker Biospec imaging spectrometer with a high strength horizontal bore magnet is available in the Center. This system is managed as part of the institutional core resources with Dr. John Hazle in Imaging Physics as the resource director. Applications include conventional MR imaging, volumetric (3-D) imaging, imaging of microvascular perfusion, diffusion imaging and in vivo localized spectroscopy or spectroscopic imaging. Custom radiofrequency devices can also be fabricated by core resources for specific imaging applications.
In Vivo Microscopy
In vivo microscopy is a unique methodology that enables real-time observation and video recording of dynamic microcirculatory events. It permits differentiation of the microvasculature into arterioles, capillaries / sinusoids and venules and allows direct observation of blood flow patterns and rates. In addition, the physical appearance and activity of normal and neoplastic cells can be documented and studied. Major equipment contained in the laboratory includes an in vivo microscope, a xenon light source and monochromator, one normal and one high sensitivity video camera, and a computer for image processing and manipulation.
Faxitron Cabinet Microradiography X-Ray System
The Faxitron cabinet microradiography x-ray system uses a thin beryllium window, a small focal spot and a high resolution film to obtain very high resolution radiographic images. This is particularly valuable for revealing the fine trabecular detail of bones and the presence of lesions. This in turn allows investigators to document tumors and structural changes. This imaging modality can also be used for microangiography to study arterioles and capillaries in detail.
Metabolic Chemistry Laboratory
The Center’s metabolic chemistry laboratory is involved in the development and evaluation of functional tumor-specific radioligands to improve scintigraphic tumor imaging and targeted delivery of therapeutic agents. Scintigraphic imaging modalities such as positron emission tomography (PET) and single photon emission computed tomography (SPECT) allow cross-sectional mapping of the location and concentration of radioactive agents. Although other imaging modalities such as CT and MRI provide considerable anatomic information, they cannot adequately differentiate residual or recurrent tumors from post-treatment tissue changes. PET and SPECT, on the other hand, can be used to detect tumors by measuring metabolic activity.
A one-of-a-kind volume computerized tomography (VCT) scanner constructed by General Electric Research and Development based on specifications developed by Imaging Physics was installed in the Center in 2003. VCT is a computerized tomography technology that uses advanced digital flat-panel x-ray detectors to perform true volumetric CT acquisitions in a single rotation. Voxels (volume elements) generated from VCT are significantly smaller than those from current CT systems, which will improve the visibility of fine anatomic structures by three orders of magnitude. The potential clinical utility of this level of detail is enormous. The instrument's improved resolution could have a dramatic effect on the detection of small lesions during routine screening as well as in the evaluation of all tumors. The improved resolution will also allow better definition of tumor boundaries for treatment planning, development of accurate automated methods to measure tumor volumes, and better visualization of lesions and surrounding normal structures using advanced visualization techniques. Finally, the improved resolution will provide a more detailed analysis of functional imaging characteristics (blood flow) using techniques such as CT perfusion.