Published in:
01-12-2015 | Original Article
Validation of prone myocardial perfusion SPECT with a variable-focus collimator versus supine myocardial perfusion SPECT with or without computed tomography-derived attenuation correction
Published in: Annals of Nuclear Medicine | Issue 10/2015
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Objective
The purpose of this study is to evaluate whether prone myocardial perfusion single-photon emission computed tomography (MPS) with thallium-201 acquired through a variable-focus collimator (IQ-SPECT) can correct for soft-tissue attenuation.
Methods
Thirty-nine patients underwent thallium-201 stress MPS with IQ-SPECT. Delayed images acquired with the patients in the prone position were compared with delayed images obtained with the patients in the supine position with computed tomography-derived attenuation correction (CTAC) (S-CTAC images) or without CTAC (S-NCTAC images). Quantitative tracer uptake (QTU) and semi-quantitative defect scores were determined for the 17 standard myocardial segments. Segments were categorized into anterior–anteroseptal, lateral, inferior, and apex, and areas with defect decision were determined by using the defect scores.
Results
Image quality in the prone images was similar to that of S-NCTAC and S-CTAC images. In male patients, QTU in prone images was equivalent to that in S-CTAC images in the anterior–anteroseptal area, but was significantly lower than that in S-CTAC images in the inferior area. In female patients, QTU in prone images was similar to that in S-CTAC images in the anterior–anteroseptal, lateral, and inferior areas. In male and in female patients, QTU in the apex was significantly greater in the prone images than that in the S-CTAC images. In the combined male and female patient group, the defect decision for prone images was similar to that for S-CTAC images in the anterior–anteroseptal, lateral, and inferior areas. Apical defects were observed more frequently in S-CTAC images than in prone or S-NCTAC images.
Conclusions
Fewer artificial defects were observed in the apex of images acquired by prone imaging than by S-CTAC imaging. Prone images improved attenuation and had similar defect decision as S-CTAC images in the anterior–anteroseptal, lateral, and inferior areas.