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A study on attenuation correction using Tc-99m external TCT source in Tc-99m GSA liver SPECT

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Abstract

Purpose: In attenuation correction of ECT images by transmission CT (TCT) with an external99mTc y-ray source, simultaneous TCT/ECT data acquisition is difficult, when the same radionuclide such as99mTc-tetrofosmin or99mTc-GSA is used as the tracer. In this case, TCT is usually acquired before administration of the tracer, and ECT is acquired separately after the tracer injection. However, misregistration may occur between the TCT and ECT images, and the repetition of examinations add to the mental and physical stress of the patients. In this study, to eliminate this problem, we evaluated whether attenuation correction of ECT images can be achieved by acquiring TCT and ECT simultaneously, then acquiring ECT alone, and preparing an attenuation map by subtracting the latter from the former using99mTc-GSA liver ECT.Method: The ECT system used was a three-head gamma camera equipped with one cardiac fan beam collimator and two parallel beam collimators. External y-ray source for TCT of99mTc was 740 MBq, and ECT of99mTc-GSA was 185 MBq. First, pure TCT data were acquired for the original TCT-map, then, ECT/TCT data were acquired for the subtracted TCT-map, and finally, pure ECT data were acquired. The subtracted attenuation map was produced by subtracting the pure ECT image from the TCT/ECT image, and attenuation correction of the ECT image was done using both this subtracted TCT map and attenuation map from pure TCT. These two attenuation corrected images and non-corrected images were compared. Hot rods phantom, a liver phantom with a defect, and 10 patients were evaluated.Results: Attenuation corrected ECT values using the subtraction attenuation map showed an error of about 5% underestimation compared with ECT values of the images corrected by original attenuation map at the defect in the liver phantom. A good correlation of y = 22.65 + 1.06x, r = 0.958 was observed also in clinical evaluation.Conclusion: By means of the method proposed in this study, it is possible to perform simultaneous TCT/ECT data acquisition for attenuation correction using Tc-99m external source in Tc-99m GSA liver SPECT. Moreover, it is thought that this method decreases the mental and physical stress of the patients.

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References

  1. 1.

    Murase K, Tanada S, Inoue T, Sugawara Y, Hamamoto K. Improvement of brain single photon emission tomography (SPET) using transmission data acquisition in a four-head SPET scanner.Eur J Nucl Med 1993; 20: 32–38.

  2. 2.

    Jaszczak RJ, Gilland DR, Hanson MW, Jang S, Greer KL, Coleman RE. Fast Transmission CT for Determining Attenuation Maps Using a Collimated Line Source, Rotatable Air-Copper-Lead Attenuators and Fan-Beam Collimation.J Nucl Med 1993; 34: 1577–1586.

  3. 3.

    Ficaro EP, Fessier JA, Ackermann RJ, Rogers WL, Corbett JR, Chwaiger M. Simultaneous transmission-emission thallium-201 cardiac SPECT: effects of attenuation correction on myocardial tracer distribution.J Nucl Med 1995; 36: 921–931.

  4. 4.

    Ogawa K. Simulation study of triple-energy-window scatter correction in combined Tl-201, Tc-99m SPECT.Ann Nucl Med 1995; 8: 277–281.

  5. 5.

    Motomura N, Ichihara T, Takayama T, Nishihara K, Inouye T, Kataoka T, et al. Practical method for reducing truncation artifacts in a fan beam transmission CT system.J Nucl Med 1998; 39: (Suppl) 178.

  6. 6.

    Hudson HM, Larkin RS. Accelerated image reconstruction using ordered subsets of projection data.IEEE Trans Med Imaging 1994; MI-13: 601–609.

  7. 7.

    Murase K, Tanada S, Sugawara Y, Tauxe WN, Hamamoto K. An evaluation of the accelerated expectation maximization algorithms for single-photon emission tomography image reconstruction.EurJ Nucl Med 1994; 21: 597–603.

  8. 8.

    Takahashi Y, Murase K, Higashino H, Sogabe I, Sakamoto K. Receiver operating characteristic (ROC) analysis of image reconstructed with iterative expectation maximization algorithms.Ann Nucl Med 2001; 15: 521–525.

  9. 9.

    Torizuka K, Ha-Kawa SK, Ikekubo K, Suga Y, Tanaka Y, Hino M, et al. Phase I clinical study on99mTc-GSA, a new agent for functional imaging of the liver.KAKU IGAKU (Jpn J Nucl Med) 1991; 28: 1321–1331. (in Japanese)

  10. 10.

    Ardekani BA, Braun M, Hutton BF, Kanno I, Iida H. A Fully Automatic Multimodality Image Registration Algorithm.J Comput Assist Tomogr 1995; 19: 615–623.

  11. 11.

    Laere DL, Koole M, Kauppinen T, Monsieurs M, Bouwens L, Dierck R. Nonuniform Transmission in Brain SPECT Using201Tl,153Gd, and99mTc Static Line Sources: Anthropomorphic Dosimetry Studies and Influence on Brain Quantification.J Nucl Med 2000; 41: 2051–2062.

  12. 12.

    Malko JA, Van Heertum RL, Gullberg GT, Kowalsky WP. SPECT liver imaging using an iterative attenuation correction algorithm and external flood source.J Nucl Med 1986; 27: 701–705.

  13. 13.

    Strauss LG, Clorius JH, Frank T, Van Kaick G. Single photon emission computerized tomography (SPECT) for estimates of liver and spleen volume.J Nucl Med 1984; 25: 81–85.

  14. 14.

    Ichihara T, Maeda H, Yamakado K, Motomura N, Matsumura K, Takeda K, et al. Quantitative analysis of scatter- and attenuation-compensated dynamic single-photon emission tomography for functional hepatic imaging with a receptor-binding radiopharmaceutical.Eur J Nucl Med 1997; 24: 59–67.

  15. 15.

    Murase K, Tanada S, Inoue T, Sugawara Y, Hamamoto K. Effect of misalignment between transmission and emission scans on SPECT images.J Nucl Med Technol 1993; 21: 152–156.

  16. 16.

    Matsumoto M, Kojima A, Ooyama Y, Kira T, Kira M, Yokoyama T, et al. An investigation of the scatter from TCT data using sheet source and its compensation.KAKU IGAKU (Jpn J Nucl Med) 1997; 34: 701. (in Japanese)

  17. 17.

    Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement.Lancet 1986; 1: 307–310.

  18. 18.

    Cho K, Kumita S, Okada S, Kumazaki T. Development of respiratory gated myocardial SPECT system.J Nucl Cardiol 1999; 6: 20–28.

  19. 19.

    Ha-kawa SK, Nakanishi K, Kojima M, Tanaka Y, Kitagawa S, Kubota Y, et al. Clinical application of asialoglycoprotein receptor-mediated liver scintigraphy using99mTc-DTPA-galactosyl-human serum albumin.Jpn J Radiol Soc 1991; 51: 1489–1497. (in Japanese)

  20. 20.

    Takahashi Y, Matsuki H, Mochizuki T. Basic study of continuous repetitive data acquisition using a phantom.KAKU IGAKU (Jpn J Nucl Med) 1996; 33: 1363–1369. (in Japanese)

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Correspondence to Yasuyuki Takahashi or Kenya Murase or Teruhito Mochizuki or Hiroshi Higashino or Yoshifumi Sugawara or Akiyoshi Kinda.

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Takahashi, Y., Murase, K., Mochizuki, T. et al. A study on attenuation correction using Tc-99m external TCT source in Tc-99m GSA liver SPECT. Ann Nucl Med 18, 585–590 (2004). https://doi.org/10.1007/BF02984580

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Key words

  • transmission computed tomography
  • 99mTc-GSA
  • subtraction attenuation map