{"title":"Improving 99mTc-tetrofosmin Myocardial Perfusion Images by Time Subtraction Technique","authors":"Yasuyuki Takahashi, Hayato Ishimura, Masao Miyagawa, Teruhito Mochizuki","volume":108,"journal":"International Journal of Medical and Health Sciences","pagesStart":887,"pagesEnd":892,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/10005060","abstract":"
Quantitative measurement of myocardium perfusion is possible with single photon emission computed tomography (SPECT) using a semiconductor detector. However, accumulation of 99m<\/sup>Tc-tetrofosmin in the liver may make it difficult to assess that accurately in the inferior myocardium. Our idea is to reduce the high accumulation in the liver by using dynamic SPECT imaging and a technique called time subtraction. We evaluated the performance of a new SPECT system with a cadmium-zinc-telluride solid-state semi- conductor detector (Discovery NM 530c; GE Healthcare). Our system acquired list-mode raw data over 10 minutes for a typical patient. From the data, ten SPECT images were reconstructed, one for every minute of acquired data. Reconstruction with the semiconductor detector was based on an implementation of a 3-D iterative Bayesian reconstruction algorithm. We studied 20 patients with coronary artery disease (mean age 75.4 ± 12.1 years; range 42-86; 16 males and 4 females). In each subject, 259 MBq of 99m<\/sup>Tc-tetrofosmin was injected intravenously. We performed both a phantom and a clinical study using dynamic SPECT. An approximation to a liver-only image is obtained by reconstructing an image from the early projections during which time the liver accumulation dominates (0.5~2.5 minutes SPECT image-5~10 minutes SPECT image). The extracted liver-only image is then subtracted from a later SPECT image that shows both the liver and the myocardial uptake (5~10 minutes SPECT image-liver-only image). The time subtraction of liver was possible in both a phantom and the clinical study. The visualization of the inferior myocardium was improved. In past reports, higher accumulation in the myocardium due to the overlap of the liver is un-diagnosable. Using our time subtraction method, the image quality of the 99m<\/sup>Tc-tetorofosmin myocardial SPECT image is considerably improved.<\/p>\r\n","references":"[1]\tG. Germano, T. Chua, H. Kiat, J. S. Areeda, D. S. Berman, \u201cA quantitative phantom analysis of artifacts due to hepatic activity in technetium-99m myocardial SPECT studies,\u201d J Nucl Med, vol. 35, no. 2, pp. 356\u2013359, Feb. 1994.\r\n[2]\tY. Takahashi, Y. Yuyama, S. Yagi, M. Kitagawa, Y. Kimura, M. Abe, et al, \u201cInfluence of hepatic accumulation of 123I-MIBG on myocardial imaging,\u201d Ehime JM, vol. 30, no. 1, pp. 13\u201318, Apr. 1994 (in Japanese).\r\n[3]\tB. A. Herzog, R. R. Buechel, R. Kats, M. Brueckner, L. Husmann, I. A. Burger, et al, \u201cNuclear myocardial perfusion imaging with a cadmium-zinc-telluride detector technique: optimized protocol for scan time reduction,\u201d J Nucl Med, vol. 51, no. 1, pp. 46\u201351, Jan. 2010.\r\n[4]\tY. Takahashi, M. Miyagawa, Y. Nishiyama, H. Ishimura, T. Mochizuki, \u201cPerformance of a semiconductor SPECT system: comparison with conventional Anger-type SPECT,\u201d Ann Nucl Med, vol. 27, no. 1, pp. 11\u201316, Jan. 2013.\r\n[5]\tK. Erlandsso, K. Kacperski, D. van Gramberg, B. F. Hutton. \u201cPerformance evaluation of D-SPECT: a novel SPECT system for nuclear cardiology,\u201d Phys. Med. Biol, vol. 9, no. 54, pp. 2635\u20132649, Sep. 2009.\r\n[6]\tR. R. Buechel, B. A. Herzog, L. Husmann, I. A. Burger, A. P. Pazhenkottil, V. Treyer, et al. \u201cUltrafast nuclear myocardial perfusion imaging on a new gamma camera with semiconductor detector technique: first clinical validation,\u201d Eur J Nucl Med Mol Imaging, vol. 4, no. 37, pp. 773\u2013778, Apr. 2010.\r\n[7]\tT. Hebert, R. Leath. \u201cA generalized EM algorithm for 3D Bayesian reconstruction from Poisson data using Gibbs priors,\u201d IEEE Trans Med Imaging, vol. 2, no. 8, pp. 194\u2013202, Jun. 1989.\r\n[8]\tG. Germano, H. Kiat, P. Kavanagh, M. Moriel, M. Mazzanti, H. Su, et al. \u201cAutomatic quantification of ejection fraction from gated myocardial perfusion SPECT,\u201d J Nucl Med, vol. 11, no. 36, pp. 2138\u20132124, Nov. 1995.\r\n[9]\tNEMA Standards publication NU 1-2001, \u201cPerformance measurements of scintillation cameras,\u201d 2001.\r\n[10]\tA. Takaki, K. Okada, J. Urata, H. Matsuda, Y. Takao, \u201cReduction of the influence of the liver uptake to the myocardial uptake on technetium-99m myocardial SPECT : Usefulness and problems of a mask processing method,\u201d Jpn J Nucl Med, vol. 36, no. 5, pp. 459\u2013465, Jul. 1999 (in Japanese).\r\n[11]\tM. Funahashi, T. Shimonagata, K. Mihara, K. Kashiyama, R. Shimizu, S. Machida, et al, \u201cApplication of pixel truncation to reduce intensity artifacts in myocardial SPECT imaging with Tc-99m tetrofosmin,\u201d J Nucl Cardiol, vol. 9, no. 6, pp. 622\u2013631, Nov. 2002 (in Japanese).","publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 108, 2015"}