Development of 4D mathematical observer models for the task-based evaluation of gated myocardial perfusion SPECT

Lee, Taek Soo; Frey, Eric; Tsui, B.M.W.

doi:10.1088/0031-9155/60/7/2751

Cited by 3 publications

(2 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In order to objectively optimize the weighting parameters, task-based evaluation and optimization are needed. In Lee et al (2015aLee et al ( , 2015b, human observer studies with ROC analysis and a channelized hotelling observer (CHO) with 4D channels were used to optimize the parameters of a Gibbs prior for the 4D MAP reconstruction for the task of detecting regional wall motion abnormality. Both mathematical and human observers showed that with optimal weighting parameters, the 4D MAP reconstruction is superior to 3D reconstruction for detecting abnormal wall motions.…”

Section: Optimization and Evaluation Of Multi-dimensional Image Recon...mentioning

confidence: 99%

Recent advances in cardiac SPECT instrumentation and imaging methods

Liu

2019

Phys. Med. Biol.

View full text Add to dashboard Cite

Cardiac SPECT continues to play a critical role in detecting and managing cardiovascular disease, in particularly coronary artery disease (CAD) (Jaarsma et al 2012 J. Am. Coll. Cardiol. 59 1719–28), (Agostini et al 2016 Eur. J. Nucl. Med. Mol. Imaging 43 2423–32). While conventional dual-head SPECT scanners using parallel-hole collimators and scintillation crystals with photomultiplier tubes are still the workhorse of cardiac SPECT, they have the limitations of low photon sensitivity (~130 count s−1 MBq−1), poor image resolution (~15 mm) (Imbert et al 2012 J. Nucl. Med. 53 1897–903), relatively long acquisition time, inefficient use of the detector, high radiation dose, etc. Recently our field observed an exciting growth of new developments of dedicated cardiac scanners and collimators, as well as novel imaging algorithms for quantitative cardiac SPECT. These developments have opened doors to new applications with potential clinical impact, including ultra-low-dose imaging, absolute quantification of myocardial blood flow (MBF) and coronary flow reserve (CFR), multi-radionuclide imaging, and improved image quality as a result of attenuation, scatter, motion, and partial volume corrections (PVCs). In this article, we review the recent advances in cardiac SPECT instrumentation and imaging methods. This review mainly focuses on the most recent developments published since 2012 and points to the future of cardiac SPECT from an imaging physics perspective.

show abstract

Section: Optimization and Evaluation Of Multi-dimensional Image Recon...mentioning

confidence: 99%

Recent advances in cardiac SPECT instrumentation and imaging methods

Liu

2019

Phys. Med. Biol.

View full text Add to dashboard Cite

show abstract

“…Currently, there are limited studies of spatiotemporal numerical observers. Previously, Lee et al, 38,39 developed a numerical 4D CHO and applied it to the task-based evaluation of gated-myocardial perfusion SPECT images. They reorganized the 4D images into a set of 2D cine images, treating a 4D image as a set of moving 2D images.…”

Section: Introductionmentioning

confidence: 99%

4D numerical observer for lesion detection in respiratory‐gated PET

Lorsakul

Trott

et al. 2014

Medical Physics

View full text Add to dashboard Cite

Purpose: Respiratory-gated positron emission tomography (PET)/computed tomography protocols reduce lesion smearing and improve lesion detection through a synchronized acquisition of emission data. However, an objective assessment of image quality of the improvement gained from respiratorygated PET is mainly limited to a three-dimensional (3D) approach. This work proposes a 4D numerical observer that incorporates both spatial and temporal informations for detection tasks in pulmonary oncology. Methods: The authors propose a 4D numerical observer constructed with a 3D channelized Hotelling observer for the spatial domain followed by a Hotelling observer for the temporal domain. Realistic 18 F-fluorodeoxyglucose activity distributions were simulated using a 4D extended cardiac torso anthropomorphic phantom including 12 spherical lesions at different anatomical locations (lower, upper, anterior, and posterior) within the lungs. Simulated data based on Monte Carlo simulation were obtained using 4 application for tomographic emission (GATE). Fifty noise realizations of six respiratory-gated PET frames were simulated by GATE using a model of the Siemens Biograph mMR scanner geometry. PET sinograms of the thorax background and pulmonary lesions that were simulated separately were merged to generate different conditions of the lesions to the background (e.g., lesion contrast and motion). A conventional ordered subset expectation maximization (OSEM) reconstruction (5 iterations and 6 subsets) was used to obtain: (1) gated, (2) nongated, and (3) motion-corrected image volumes (a total of 3200 subimage volumes: 2400 gated, 400 nongated, and 400 motion-corrected). Lesion-detection signal-to-noise ratios (SNRs) were measured in different lesion-to-background contrast levels (3.5, 8.0, 9.0, and 20.0), lesion diameters (10.0, 13.0, and 16.0 mm), and respiratory motion displacements (17.6-31.3 mm). The proposed 4D numerical observer applied on multiple-gated images was compared to the conventional 3D approach applied on the nongated and motion-corrected images. Results: On average, the proposed 4D numerical observer improved the detection SNR by 48.6% (p < 0.005), whereas the 3D methods on motion-corrected images improved by 31.0% (p < 0.005) as compared to the nongated method. For all different conditions of the lesions, the relative SNR measurement (Gain = SNR Observed /SNR Nongated ) of the 4D method was significantly higher than one from the motion-corrected 3D method by 13.8% (p < 0.02), where Gain 4D was 1.49 ± 0.21 and Gain 3D was 1.31 ± 0.15. For the lesion with the highest amplitude of motion, the 4D numerical observer yielded the highest observer-performance improvement (176%). For the lesion undergoing the smallest motion amplitude, the 4D method provided superior lesion detectability compared with the 3D method, which provided a detection SNR close to the nongated method. The investigation on a structure of the 4D numerical observer showed that a Laguerre-Gaussian channel matrix with a volumetric 3D function y...

show abstract