PET Image Reconstruction via Intra-Crystal Compton Event Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional PET image reconstruction methods filter out intra-crystal Compton scattering events, leading to reduced coincidence event counts and decreased system sensitivity.
Innovation Solution
A method and apparatus that identify and restore intra-crystal Compton scattering events by matching energy and time criteria between first and second scan data sets, converting these events into coincidence events for improved image reconstruction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If intra-crystal Compton scattering events are filtered out based on energy threshold, then image reconstruction quality is improved by removing scattered photons, but coincidence event count decreases leading to reduced system sensitivity
Solution Approach 1:
The patent converts harmful intra-crystal Compton scattering events into beneficial coincidence events by identifying scattered photons that still contain useful information and reclassifying them. Instead of discarding these scattered photons through energy threshold filtering, the system recovers them by matching first scan data sets (containing scattered photons) with second scan data sets (containing corresponding unscattered photons), thereby transforming a harmful filtering action into a beneficial data recovery process that increases coincidence event count while maintaining image quality
Solution Approach 2:
The patent changes the classification parameters for identifying valid coincidence events. Rather than using a single energy threshold parameter that discards scattered photons, the system introduces a multi-parameter matching approach that considers temporal correlations, spatial relationships, and energy deposits across multiple detector crystals. This parameter change allows scattered photons to be recovered and included in the coincidence event data set, resolving the contradiction between filtering quality and event count
2Measurement precision
If energy threshold filtering is applied to remove Compton scattered photons, then measurement accuracy is improved, but system sensitivity decreases due to lower total count rate
Solution Approach 1:
The patent transforms the harmful effect of Compton scattering (which reduces measurement accuracy) into a beneficial source of additional coincidence events. By recovering scattered photons through the matching process between first and second scan data sets, the system converts what was previously considered noise or error into useful signal, thereby improving system sensitivity without sacrificing measurement accuracy
Solution Approach 2:
The patent implements a feedback mechanism where the system continuously identifies and recovers scattered photons by matching scan data sets. The recovered coincidence events are fed back into the image reconstruction process, creating a positive feedback loop that continuously improves system sensitivity. This feedback approach allows the system to adaptively recover scattered photons while maintaining accurate photon detection through the matching criteria
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Increases coincidence event counts and enhances the sensitivity of PET systems by effectively incorporating previously filtered data into image reconstruction.
Implementation Method 1
the detector includes a plurality of crystals and corresponding a plurality of photoelectric converters
Implementation Method 2
each of the first scan data sets corresponds to an intra-crystal Compton scattering event occurred in a plurality of crystals of a detector
Data Source
AI summary
The present disclosure relates to reconstructing an image. According to an embodiment of the present disclosure, identifying a plurality of first scan data sets and a second scan data set from PET scan data, wherein each of the first scan data sets corresponds to an intra-crystal Compton scattering event occurred in a plurality of crystals of a detector and includes two or more first single event data groups, and each of the first single event data groups comprises an energy value less than a preset first energy threshold, the second scan data set comprises one or more second single event data groups and each of the second single event data groups comprises an energy value exceed a preset second energy threshold; for each of the plurality of first scan data sets: searching the second scan data set for a target second single event data group which matches with the first scan data set; obtaining first coincidence event data from each of the first single event data groups in the first scan data set and the target second single event data group as coincidence event data recovered from an intra-crystal Compton scattering event corresponding to the first scan data set; reconstructing an image with the first coincidence event data and second coincidence event data which involves coincidence events corresponding to the second scan data set.