Design criteria for a high energy Compton Camera and possible application to targeted cancer therapy

Abstract

The proposed research focuses on the design criteria for a Compton Camera with high spatial resolution and sensitivity, operating at high gamma energies and its possible application for molecular imaging. This application is mainly on the detection and visualization of the pharmacokinetics of tumor targeting substances specific for particular cancer sites. Expected high resolution (< 0.5 mm) permits monitoring the pharmacokinetics of labeled gene constructs in vivo in small animals with a human tumor xenograft which is one of the first steps in evaluating the potential utility of a candidate gene. The additional benefit of high sensitivity detection will be improved cancer treatment strategies in patients based on the use of specific molecules binding to cancer sites for early detection of tumors and identifying metastasis, monitoring drug delivery and radionuclide therapy for optimum cell killing at the tumor site. This new technology can provide high resolution, high sensitivity imaging of a wide range of gamma energies and will significantly extend the range of radiotracers that can be investigated and used clinically. The small and compact construction of the proposed camera system allows flexible application which will be particularly useful for monitoring residual tumor around the resection site during surgery. It is also envisaged as able to test the performance of new drug/gene-based therapies in vitro and in vivo for tumor targeting efficacy using automatic large scale screening methods.

Hybrid PET/Compton-camera imaging: an imager for the next generation

“…Compton cameras have long been evaluated for medical applications given their promising advantages over collimated cameras: high sensitivity, large FOV, good separation of different isotopes and use of high-energy radiotracers with lower attenuation in the patient. Numerous Monte-Carlo simulations keep showing potential benefits [45][46][47][48] that are still hard to translate into clinical use, since the competition with a well-established and affordable technology such as SPECT is complex. In particular, many approaches have not yet reached sufficient maturity in terms of technology and software development, e.g., image reconstruction or corrections for attenuation and scatter.…”

“…The radionuclides employed (such as 149 Tb, 211 At, 212 Bi, 213 Bi, 223 Ra, 225 Ac, 227 Th, among others) emit secondary photons that can be employed to image the drug distribution. Given their high energies, Compton cameras can offer a potentially better alternative [6,47] to gamma cameras. Different systems are being tested, e.g., for imaging 211 At [70], or combining a pinhole and a Compton camera to detect both X-rays and gamma-rays for imaging a mouse [71].…”

Compton and Proximity Imaging of Ac In Vivo With a CZT Gamma Camera: A Proof of Principle With Simulations

“…Other Compton camera systems have been proposed in [24]- [30] and [50]. The particular difference of our approach is that we focus on maximizing the sensitivity, which is predicted to be one or two orders of magnitude larger than those.…”

Quantitative Imaging of Alpha-Emitting Therapeutic Radiopharmaceuticals

“…Imaging of bremsstrahlung radiation, if there is a good amount of its radiation, and Cerenkov luminescence imaging for radionuclides emitting energetic beta particles are other possibilities. Finally, for imaging of high-energy photons (e.g., > 0.5 MeV) that are not very well captured by conventional gamma cameras, Compton imaging method can be employed since very sensitive Compton cameras can be designed and built with high spatial resolution [2].…”