Quantification of Systolic Count Increase in Technetium-99m-MIBI Gated Myocardial SPECT

• Published in: The Journal of nuclear medicine (1978) Vol. 38; no. 7; pp. 1067 - 1073
• Main Authors: Fukuchi, Kazuki, Uehara, Toshiisa, Morozumi, Takakazu, Tsujimura, Eiichiro, Hasegawa, Shinji, Yutani, Kenji, Kusuoka, Hideo, Nishimura, Tsunehiko
• Format: Journal Article
• Language: English
• Published: Reston, VA Soc Nuclear Med 01.07.1997; Society of Nuclear Medicine
• Subjects: Adult; Biological and medical sciences; Cardiovascular system; Dobutamine - pharmacology; Echocardiography; Electrocardiography; Heart - diagnostic imaging; Heart - drug effects; Humans; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Phantoms, Imaging; Radionuclide investigations; Radiopharmaceuticals; Systole; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Radionuclide study; Sonography; Human; Test objet; Associated technique; Echocardiography; Photon; Thickness measurement; Electrodiagnosis; Electrocardiography; Circulatory system; Technetium(99mTc) sestamibi; Comparative study; Quantitative analysis; Emission tomography
• ISSN: 0161-5505; 1535-5667

This study was performed to clarify the validity of quantification of myocardial wall thickening by the count increase method using electrocardiography (ECG)-gated SPECT. We performed a phantom study to examine the quantification of this method and to clarify the relationship between the changes of relative counts and objective size (such as myocardial wall) under various conditions. In addition, in volunteers, the percent count increase (%CI) was analyzed in left ventricular segments based on circumferential profile curve analysis by ECG-gated SPECT with 99mTc-MIBI (methoxyisobutyl-isonitrile), and it was compared with the regional systolic wall thickness (%Th) assessed by echocardiography during low-dose dobutamine infusion. In our phantom study, the relative count changes were correlated linearly with the object size only within less than 20 mm. Recovery coefficient curves were influenced by acquisition parameters such as type of collimator, diameter of camera rotation, counts and photon scattering. In ECG-gated SPECT, the %CI value was increased gradually at each stage after dobutamine infusion, in relation to the increase of the %Th seen on echocardiography, although there are significant large deviations between these two parameters. In this study, quantitative analysis based on the %CI in ECG-gated SPECT may underestimate regional wall thickening. These data should be considered in the evaluation of the %CI as an index of myocardial function.