SBIR-STTR Award

We will develop a prototype intraoperative gamma-ray camera (IOGC) for imaging gamma-emitting radioactive tracers incorporated into brain tumors in the intraoperative surgical environment. This instrument will be capable of dynamically identifying tumor cells for removal from patients with cerebral neoplasm without removing excessive normal tissue. The camera will be used in the surgical scenario where the patient is injected with a tumor seeking radiopharmaceutical before surgery, the surgical procedure to remove the tumor mass is performed, and the site is then imaged using the IOGC probe to locate residual subclinical tumor cells. The IOGC would be employed for radioisotopes such as 99mTc, 201TI, and 1231 which have low energy X- and gamma-rays. The intraoperative gamma-ray camera will use a small and light-weight detachable head comprising a mercuric iodide (Hgl2) detector array in order to ensure compact design and high signal-to-noise ratio. During the first phase of the work, a study will be conducted to determine the optimal construction of the detector probe and the resulting design will be incorporated into a small (19 element) prototype array which will be fabricated and evaluated.Awardee's statement of the potential commercial applications of the research: Addresses the need for miniature and portable gamma cameras, and in particular intraoperative imaging camera to improve the success of tumor removal surgeries. The modular deign of this gamma-ray camera will allow for its use with various front-end imaging probes specifically tailored for other regional applications such as colorectal carcinoma, lung, thyroid and bone cancers.National Cancer Institute (NCI)

The goal of this proposal is to develop a prototype intraoperative gamma-ray camera (IOGC) specifically designed for use in imaging gamma- emitting radiopharmaceuticals (such as 99m-Tc labeled Sestamibi) incorporated into brain tumors in the intraoperative surgical environment. The patient is injected with a tumor seeking radiopharmaceutical before surgery, the surgical procedure to remove the tumor mass is performed, and the site is then imaged using the IOGC probe to locate residual subclinical tumor cells. The proposed system is intended to improve the success of tumor removal surgeries by allowing more complete removal of subclinical tumor cells without removal of excessive normal tissue. The intraoperative gamma-ray camera will use a small and lightweight detachable head comprising a 256-pixel mercuric iodide (HgI2 detector array. During the Phase I feasibility study prototypical 19-element arrays were designed, built and characterized. The performance of the devices in terms of energy resolution, spatial resolution and uniformity proved the feasibility of the chosen approach, and exceeded the initial specifications. In Phase II a complete intraoperative imaging system including a 256-pixel imaging probe, processing electronics, and data collection hardware and software will be designed and developed. In the first year several detector arrays will be designed, built, fabricated, and evaluated at various levels in a specialized test chamber using brain tumor phantoms filled with medical radioisotopes. In the second year the probe and associated imaging system electronics and software will be completed, integrated and evaluated. The probe construction will be optimized for operation proximal to the tissue of the patient in, the surgical field in order to give the best sensitivity, spatial resolution, and contrast. PROPOSED COMMERCIAL APPLICATION: This proposal is motivated by the need for commercial intraoperative imaging cameras to improve the success of tumor removal surgeries. The proposed work is focused on a novel system to be constructed for patients with brain tumors. In addition, part of the proposed work will be to show that the design of the gamma- ray camera can be extended to accommodate various geometries, numbers of pixels, and specifications that will apply to additional clinical and commercial interests such as the identification of breast tumors in dense breast and assessment of malignancy in lesions identified as suspicious in mammography.

Thesaurus Terms:
biomedical equipment development, clinical biomedical equipment, gamma radiation, neoplasm /cancer surgery, radiation detector, radionuclide scanning /imaging, radiopharmacology brain neoplasm, brain visualization, computer program /software, computer system design /evaluation, computer system hardware, digital imaging, image processing, neoplasm /cancer radiodiagnosis, neurosurgery, phantom model, surgery material /equipment computer processing of clinical data