Japanese
Title201Tl心筋SPECTにおけるトランスミッション・エミッションデータ同時収集法の評価
Subtitle《技術報告》
Authors冨口静二*, 大山洋一*, 吉良朋広*, 吉良光子*, 中島留美*, 辻明徳*, 古嶋昭博*, 松本政典**, 高橋睦正*, 井野辺義人***, 泰江弘文***
Authors(kana)
Organization*熊本大学医学部放射線科, **熊本大学医療技術短期大学部診療放射線技術学科, ***熊本大学医学部循環器内科
Journal核医学
Volume33
Number9
Page1027-1035
Year/Month1996/9
Article報告
Publisher日本核医学会
Abstract「要旨」201Tl心筋SPECTで3検出器型ガンマカメラによる99mTcをトランスミッション線源としたトランスミッション・エミッションデータ同時収集法を用いて不均一吸収体に対する減弱補正を行い, その有用性と問題点について検討した. ファントム実験では心基部の減弱が改善されるため, 心筋全体の均一性が向上し減弱補正に有用であった. 臨床例においては負荷時および安静時とも下壁および中隔の減弱は補正されているが, ファントム実験の結果に比べ, 下壁でのカウントが前壁より高くなる傾向を認めた. このような傾向が強い場合には正常例でも, 視覚的には前壁のカウントが低下しているように見える場合があり, 部分容積効果に加え肝臓からの散乱線による下壁のカウントの増加もその一因と考えられた. トランスミッション・エミッションデータ同時収集法は不均一吸収体における減弱補正に有用と考えられるが, さらに完全な定量性を求めるためには散乱線補正も同時に必要と思われた.
Practice臨床医学：一般
KeywordsThallium-201 myocardial SPECT, Transmission tomography, Coronary artery disease, Attenuation correction.
English
TitleEvaluation of Simultaneous Acquisition of Transmission and Emission Data on Thallium-201 Myocardial SPECT
Subtitle
AuthorsSeiji TOMIGUCHI*, Yoichi OYAMA*, Tomohiro KIRA*, Mitsuko KIRA*, Rumi NAKASHIMA*, Akinori TSUJI*, Akihiro KOJIMA*, Masanori MATSUMOTO**, Mutsumasa TAKAHASHI*, Yoshito INOBE***, Hirofumi YASUE***
Authors(kana)
Organization*Department of Radiology, ***Division of Cardiology, Kumamoto University Medical School, **Department of Radiological Technology, Kumamoto University College of Medical Science
JournalThe Japanese Journal of nuclear medicine
Volume33
Number9
Page1027-1035
Year/Month1996/9
ArticleReport
PublisherTHE JAPANESE SOCIETY OF NUCLEAR MEDICINE
AbstractThis study evaluates the usefulness of attenuation correction on regional myocardial tracer distributions defined by Thallium-201 myocardial SPECT images obtained from cardiac phantoms and patients with or without coronary heart disease. A three-detector SPBCT system equipped with a Technetium-99m line source and a fan-beam collimator was used for simultaneous transmission and emission data acquisition. All three detectors were equipped with fan-beam collimators. Thallium-201 myocardial scintigraphy was performed on phantom study and 19 patients. Transmission images, uncorrected and corrected emission images were iteratively reconstructed with a EM-ML algorithm. Attenuation map computed from the transmission data was utilized for the attenuation correction. For the phantom study, circumferential profile analysis was applied to both datasets of horizontal long-axis slices through the center of the phantom. The maximum profile value in the circumferential profile set to 100% in the normalized uncorrected and corrected profiles. The uncorrected circumferential profiles from cardiac insert model 7070 and RH-2 cardiophantom showed decrease in activity in basal regions which appeared improvement in the attenuation corrected profiles. In clinical study, the inferior-to-anterior activity ratio, changed from 0.78+-0.10 to 0.97+-0.11 on stress images in patients with inferior ischemia and from 0.96+-0.12 to 1.15+-0.13 on 4 hour delayed or rest images in normal cases. The anteroapical wall of the attenuation corrected images, however, showed a decrease in activity relative to the inferior wall in normal cases. The increase in activity in inferior wall on attenuation corrected images was observed frequently in clinical study but not in phantom study. A presence of scatter from the liver or bowels may cause the increase in activity in the inferior wall in clinical study. In conclusion, transmission scan is one of the useful methods for the attenuation correction. Scatter correction, however, is also necessary to make an accurate attenuation corrected images.
PracticeClinical medicine
KeywordsThallium-201 myocardial SPECT, Transmission tomography, Coronary artery disease, Attenuation correction.

【全文PDF】