Attenuation correction in myocardial perfusion SPECT/CT: effects of misregistration and value of reregistration
| Autor: | Zhe Zhang, Tracy L. Y. Brown, William C. Lavely, Sibyll Goetze, Frank M. Bengel |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Adult
Male Technetium Tc 99m Sestamibi medicine.medical_specialty For Attenuation Correction Body weight Myocardial perfusion imaging Coronary circulation Coronary Circulation Image Interpretation Computer-Assisted medicine Humans Radiology Nuclear Medicine and imaging Aged Aged 80 and over Tomography Emission-Computed Single-Photon medicine.diagnostic_test business.industry Heart Middle Aged medicine.anatomical_structure Tracer uptake Female Radiology Tomography Radiopharmaceuticals Nuclear medicine business Artifacts Tomography X-Ray Computed Perfusion Correction for attenuation Algorithms |
| Zdroj: | Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 48(7) |
| ISSN: | 0161-5505 |
| Popis: | The accuracy of myocardial perfusion SPECT improves with attenuation correction. Algorithms for attenuation correction in hybrid SPECT/CT systems have the potential for misregistration of emission and transmission scans because CT and SPECT are obtained sequentially. Misregistration will influence regional tracer distribution and may reduce diagnostic accuracy. This study focused on the role of misregistration in cardiac SPECT/CT and the performance of a software-based approach for reregistration.We included 105 consecutive patients who underwent clinical myocardial perfusion imaging on a SPECT/CT system. Images were quantitatively assessed for misregistration using fusion software. Results were recorded in millimeters in the x-, y-, and z-axes. Regional tracer uptake in 6 segments (anterior, septal, inferior, lateral, anteroapical, and inferoapical) for noncorrected and attenuation-corrected images before and after reregistration was obtained from polar maps. To determine the relative influence of misregistration, we correlated individual differences between noncorrected and attenuation-corrected images, as well as between attenuation-corrected images before and after reregistration, with the degree of misregistration in a multivariate analysis including additional clinical variables such as sex and body weight.The difference in regional radiotracer uptake was significant between noncorrected and attenuation-corrected images in all 6 segments and was most pronounced in the inferior wall. On multivariate analysis, misregistration contributed significantly to changes in radiotracer distribution in the anterior (P = 0.038), septal (P = 0.011), and inferior (P = 0.006) segments. The mean misregistration was 8.6 +/- 3.8 mm (1.25 +/- 0.55 pixel). Misregistration of one or more pixels was observed in 64% of studies. Reregistration of misalignment significantly affected regional radiotracer distribution in the segments shown to be influenced by misregistration.Misregistration occurs with SPECT/CT systems and influences regional tracer distribution on attenuation-corrected myocardial images. Reregistration of misaligned studies may be a useful tool for correction. The impact of this strategy on the diagnostic and prognostic accuracy of cardiac hybrid imaging needs to be determined. |
| Databáze: | OpenAIRE |
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