From X-ray astronomy to gamma scintigraphy: a high resolution gamma camera for medical imaging

Current nuclear imaging facilities use large fixed devices located in imaging departments making procedures at the bedside, in operating theatres, clinics or intensive care units extremely difficult. These ?standard? whole body gamma cameras can normally only resolve objects bigger than 6mm which limits there diagnosis capabilities for many medical applications.

Over the last few years we have been developing gamma cameras based on new technology that was originally developed for X-ray astronomy. Recently we have developed a new type of gamma camera that offers high spatial resolution imaging, enabling small objects around ~ 1 mm be clearly seen.

During the last 10 years a number of applications have emerged using nuclear medicine in operating theatres and intensive care units. In particular, the concept of sentinel node biopsy has been developed to help determine the best treatment for cancer patients. Sentinel node imaging via lymphoscintigraphy has become an important technique for determining the stage of cancer and, in particular, whether the disease has spread from the primary tumour to the lymphatic system. Many UK hospitals are assessing the sensitivity of sentinel node mapping in a range of cancers. For this procedure to be successful it is necessary to identify the sentinel node pre-operatively. Our technology offers the potential for a low-cost, high-performance method of imaging the sentinel node. Our camera would also be useful for the imaging of small organs such as the thyroid and skeletal joints (knees, ankles, elbows).
Our portable device will offer healthcare benefits by providing patients and medical teams with versatile, point-of-care technology. Such cameras would be clinically useful for radio-guided surgery, sentinel node detection and imaging small parts such as the eye and thyroid and would also find applications in gastroenterology.

We propose to investigate the use of a solid state imaging detector, originally developed for X-ray astronomy, for applications in nuclear medicine. Specifically we aim to determine if collimated, scintillator-coated, low noise Charge Coupled Devices (CCDs) can be used as a generic, low cost, high performance alternative to the ?standard? large area Gamma Camera for imaging small volumes of radionuclide uptake in tissues.
Our programme will concentrate on imaging patients in the clinical environment. We will compare the performance of our imaging detector with commercial gamma cameras used in medical imaging. In collaboration with clinicians we will also refine the current camera and its operation and produce imaging software to meet the stringent operational demands of modern hospitals.