Correction for respiration artefacts in myocardial  perfusion SPECT is more effective when  reconstructions supporting collimator detector  response compensation are applied.
OBJECTIVE
To assess the impact of respiration on myocardial perfusion imaging (MPI) SPECT processed with advanced algorithmic reconstructions.


METHODS
SPECT studies obtained from a phantom simulation and 49 respiratory-gated,one-day 99mTc-sestamibi scans were corrected for respiratory-related cardiac movement. Three types of reconstruction algorithms: (a) filtered back projection (FBP), (b) ordered subset expectation maximization in which collimator detector response was incorporated (OSEMCDR), and (c) OSEM-CDR with additional attenuation and scatter corrections (OSEM-CDRACSC) were applied to the corrected and uncorrected sets and analyzed quantitatively and qualitatively.


RESULTS
A discrepancy between the corrected and uncorrected bull's eye maps > or = 10% wasfound in 2%, 10%, and 20% of the FBP, OSEM-CDR, and OSEM-CDR-ACSC scans, respectively. In studies with more than 10-mm respiratory motion, the effect of motion was greater in OSEM-CDR and OSEM-CDR-ACSC datasets as compared to FBP processing.Qualitative and quantitative differences between corrected and uncorrected sets were significantly larger in OSEM-CDR and OSEM-CDR-ACSC data than in those of FBP data.


CONCLUSIONS
Respiratory-related cardiac motion significantly affects MPI-SPECT reconstructed with advanced high-resolution reconstruction algorithms such as OSEM-CDR and OSEM-CDR-ACSC and thus may justifies the application of respiratory gating.
Kovalski
Gil
G
Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel. bmgil@tx.technion.ac.il
Keidar
Zohar
Z
Frenkel
Alex
A
Israel
Ora
O
Azhari
Haim
H
D000465:Algorithms; D016477:Artifacts; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D055425:Respiratory-Gated Imaging Techniques / Q000379:methods*; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*