Technical and economic feasibility of a high-resolution brain SPECT imager.

Abstract

This dissertation presents the results of an investigation into the feasibility of a high-resolution brain SPECT imager based on a hemispherical multiple-pinhole coded aperture and high-intrinsic-resolution modular gamma-ray detectors. A prototype system using scintillation modular cameras has already been built which has an estimated 5 mm reconstructed resolution. New advances in semiconductor technology and their growth as gamma-ray detectors create the opportunity for a high-resolution semiconductor modular camera. This dissertation illustrates how such an increase in detector resolution will be translated into an increase in reconstructed resolution. This dissertation also reports the results of an investigation on the economic feasibility of the high-resolution brain SPECT system, both in terms of market opportunities and production costs. The simulations presented here indicate that the reconstructed resolution from a 2-mm-intrinsic-resolution detector can be expected to be close to 3 mm for nuclear medicine clinical applications. The simulations also establish the importance of a careful design of the multiple-pinhole coded aperture, in terms of pinhole-position (to avoid critical artifacts in imaging uniform object), and in obtaining quantitative information from brain SPECT images. The economic study performed here outlines different scenarios for the possible impact a high-resolution brain SPECT system could have on nuclear medicine in terms of market opportunities. Different scenarios are also described that would affect production costs. A final estimate is presented showing how the different scenarios could mesh together to provide a forecast of the evolution of the market share for the high-resolution brain SPECT imager. Based on the simulations and economic study, the future high-resolution brain SPECT imager is not only feasible, but it will likely have millimeter-range reconstructed resolution. Once proven clinically useful as a diagnostic tool, it will also presumably have an important market share and a low enough price tag to be affordable to most nuclear medicine departments.