Systems and methods for low-count quantitative projection domain SPECT imaging

A method for low-count quantitative single-photon emission computed tomography (LC-QSPECT), the method implemented by a computer device comprising at least one processor in communication with one or more memory devices and in communication with one or more sensors configured for detecting one or more emitted photons, the method comprises:

• storing a computer tomography (CT) scan of a subject being examining including a plurality of defined volumes of interest (VOIs) of the subject being examined;
• defining the plurality of defined VOIs based on the CT scan of the subject being examined, wherein the plurality of defined VOIs are different than and have different boundaries from any plurality of voxels defining the subject to be examined;
• modeling a system matrix based on the stored CT scan, wherein the model describes the probability that photons emitted from each of the plurality of defined VOIs are detected in different projection bins, wherein a plurality of projection bins are defined around the subject and the plurality of defined VOIs;
• adjusting the model with analysis of stray-radiation noise around the subject;
• detecting, by the one or more sensors, one or more photons being emitted by an alpha-particle-emitting isotope within the subject;
• and
• executing the adjusted model with the one or more detected photons as inputs to determine a source VOI of the one or more detected photons.

A computer device for low-count quantitative single-photon emission computed tomography (LC-QSPECT) comprising at least one processor in communication with at least one memory device, wherein the at least one processor is programmed to:

• store a computer tomography (CT) scan of a subject being examining including a plurality of defined volumes of interest (VOIs) of the subject being examined;
• define the plurality of defined VOIs based on the CT scan of the subject being examined, wherein the plurality of defined VOIs are different than and have different boundaries from any plurality of voxels defining the subject to be examined;
• model a system matrix based on the stored CT scan, wherein the model describes the probability that photons emitted from each of the plurality of defined VOIs are detected in different projection bins, wherein a plurality of projection bins are defined around the subject and the plurality of defined VOIs;
• adjust the model with analysis of stray-radiation noise around the subject;
• detect, by one or more sensors, one or more photons being emitted by an alpha-particle-emitting isotope within the subject;
• and
• execute the adjusted model with the one or more detected photons as inputs to determine a source VOI of the one or more detected photons.