㻌 ⤖ㄽ

㛤Ⓨ䛧䛯ప⥺㔞 CT ⏬ീ䝅䝭䝳䝺䞊䝅䝵䞁ᢏ⾡䜢⮫ᗋ⏬ീ䛻㐺⏝䛧䛯䠊ᐇ㝿䛾ప⥺㔞⏬ീ䛸䛾

᳨ᰝ᪥䛜ู᪥䛷䛒䜚䠈䝇䝷䜲䝇఩⨨䛜␗䛺䜛䠈䝅䝭䝳䝺䞊䝅䝵䞁䛾䝟䝷䝯䞊䝍Ỵᐃ䛻౑⏝䛧䛯䝣䜯䞁䝖 䝮⏬ീ䛸䝇䜻䝱䞁ᵝᘧ䛜␗䛺䜛䠈䛺䛹䛾㐪䛔䛜䛒䛳䛯䛜䠈䜋䜌ྠ➼䛾⏬ീ䛜ᚓ䜛䛣䛸䛜☜ㄆ䛷䛝䛯䠊 䛣䛾䛣䛸䛛䜙䠈ᮏᡭἲ䛿䝣䜯䞁䝖䝮ᐇ㦂䛺䛹䛻䜘䜛᫬㛫䛾ไ⣙䠈ᝈ⪅䛾⿕䜀䛟⥺㔞䛾ቑຍ䛺䛧䛻 CT

᳨ᰝ䛻䛚䛡䜛᭱㐺⥺㔞䛾Ỵᐃ䛻᭷⏝䛷䛒䜛䛸⪃䛘䜙䜜䜛䠊

➨7❶㻌 ⤖ㄒ

᧱᧰

➨7❶㻌 ⤖ㄒ

CT ᳨ᰝ䛻䛚䛡䜛ᝈ⪅⿕䜀䛟⥺㔞䛾᭱㐺໬䜢┠ⓗ䛸䛧䛯ホ౯䜢ල⌧໬䛩䜛䛯䜑䛻䠈䛭䛾デ᩿⬟

䛾ホ౯䛻౑⏝䛜ྍ⬟䛺䠈ప⥺㔞CT䝅䝭䝳䝺䞊䝅䝵䞁⏬ീ䜢సᡂ䛩䜛ᢏ⾡䜢㛤Ⓨ䛧䛯䠊

ᮏ◊✲䛷䛿䠈సᡂ䛧䛯䝅䝭䝳䝺䞊䝅䝵䞁⏬ീ䛾⏬㉁ホ౯䛻ᚲせ䛷䛒䛳䛯䛯䜑䠈ホ౯䛾䛯䜑䛾෇

ᙧ䜶䝑䝆ἲ䜢⏝䛔䛯 MTF ィ ἲ䜒䠈ྜ䜟䛫䛶㛤Ⓨ䛧䛯䠊䛣䛾 MTF 䛾᪂䛧䛔ᡭἲ䛷䛿䠈CT ⏬ീ

䛾䝜䜲䝈ᡂศ䛻䜘䜛ᙳ㡪䜢㝖ཤ䛩䜛䛯䜑䠈ESF 䜢 logistic curve-fitting 䛻䜘䜚㏆ఝ䛧䛯䠊䛣䜜䜘䜚䠈 ᮏᡭἲ䛿ඛ⾜◊✲䛸ẚ㍑䛧䠈䝜䜲䝈䛻䝻䝞䝇䝖䛺ᡭἲ䛷䛒䜛䛣䛸䛜♧䛥䜜䛯䠊

㛤Ⓨ䛧䛯ప⥺㔞CT⏬ീ䝅䝭䝳䝺䞊䝅䝵䞁ᢏ⾡䛿MTF䜔NPS䛾ィ 䛜ྍ⬟䛺௵ព䛾䝣䜯䞁䝖 䝮䛻䛴䛔䛶䠈ಶ䚻䛻䝟䝷䝯䞊䝍䜢ồ䜑䜛䛣䛸䛷䝅䝭䝳䝺䞊䝅䝵䞁䛜ྍ⬟䛸䛺䜛⡆౽䛺ᡭἲ䛷䛒䜛䠊ᮏ

◊✲䛻䜘䛳䛶⾜䜟䜜䛯䝣䜯䞁䝖䝮ᐇ㦂䜘䜚ゎീᗘ≉ᛶ䠈䝜䜲䝈≉ᛶ䛸䜒䛻ᐇ㝿䛻ప⥺㔞䛷᧜ᙳ䛥䜜 䛯⏬ീ䛸ྠ➼䛾䝅䝭䝳䝺䞊䝅䝵䞁⏬ീ䜢సᡂ䛩䜛䛣䛸䛜ྍ⬟䛷䛒䜛䛣䛸䛜♧䛥䜜䛯䠊䜎䛯⮫ᗋ⏬ീ䛻 䛚䛔䛶䜒ྠ➼䛺䝅䝭䝳䝺䞊䝅䝵䞁⏬ീ䛜ᚓ䜙䜜䜛䛣䛸䜢☜ㄆ䛧䛯䠊

௒ᚋ䠈䛥䜙䛻ప⥺㔞 CT ⏬ീ䛾⢭ᗘ䛾ྥୖ䜢ᅗ䜛䛣䛸䛻䜘䜚䠈⑓㝔䛻╀䜛኱㔞䛾⏬ീ䝕䞊䝍䜢

฼⏝䛧䠈⮫ᗋ⏬ീ䛻䛚䛡䜛⥺㔞䛸⏬㉁䛾㛵ಀ䜢䜘䜚ヲ⣽䛻᳨ウ䛩䜛䛣䛸䛜ྍ⬟䛸䛺䜚䠈᭱⤊ⓗ䛺䝂 䞊䝹䛸䛧䛶䠈䛣䜜䜙䛾䝅䝭䝳䝺䞊䝅䝵䞁⏬ീ䜢⏝䛔䛯デ᩿⬟䛾ホ౯䜢⾜䛖䛣䛸䛷䠈ᝈ⪅ಶேಶே䛻䛚 䛔䛶デ᩿䛻ᚲせ䛸䛥䜜䜛᭱㐺⥺㔞䜢Ỵᐃ䛧䠈㐺⏝䛩䜛䛣䛸䛜ྍ⬟䛻䛺䜛䛸⪃䛘䜛䠊

ཧ⪃ᩥ⊩

᧱᧱

ཧ⪃ᩥ⊩

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ཧ⪃ᩥ⊩

᧱᧲

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ཧ⪃ᩥ⊩

᧱᧳

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㍑ホ౯, ་⏝⏬ീ᝟ሗᏛ఍㞧ㄅ, 25(2): 29-34.

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⥺ᢏ⾡Ꮫ఍㞯ㄅ, 2008; 64(6): 672-80.

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ཧ⪃ᩥ⊩

᧱᧴

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Bellingham: SPIE Press; 2003. p. 113-8. 235-8.

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50.

ᴗ⦼୍ぴ

᧱᧵

ᴗ⦼୍ぴ ᰝㄞ䛺䛧ㄽᩥ

1) T. Takenaga, M. Goto, M. Hatemura, Y. Uchiyama, S. Katsuragawa, J. Shiraishi, Computer simulation of low-dose clinical CT images, The second International Conference on Radiological Science and Technology, 55-56, 2014. 䠄Proceeding, ᰝㄞ䛺䛧䠅

ᰝㄞ᭷䜚ㄽᩥ

2) T. Takenaga, S. Katsuragawa, M. Goto, M. Hatemura, Y. Uchiyama䠈J. Shiraishi, A computer simulation method for low-dose CT images by use of real high-dose images: a phantom study, Radiological Physics and Technology, Aug., 2015.䠄 ᰝ ㄞ ᭷ 䞉Published online䠅

3) T. Takenaga, S. Katsuragawa, M. Goto, M. Hatemura, Y. Uchiyama䠈J. Shiraishi, Modulation transfer measurement of CT images by use of a circular edge method with a logistic curve-fitting technique, Radiological Physics and Technology, 8, 53-59, 2015. 䠄ᰝ ㄞ᭷䠅

ᅜ㝿఍㆟䛻䛚䛡䜛Ⓨ⾲

4) T. Takenaga, S. Katsuragawa, M. Goto, M. Hatemura, Y. Uchiyama, J. Shiraishi, Real-time demonstration of simulated low-dose clinical CT images, RSNA, PHE0010B, USA Chicago, November 2014. 䠄䝫䝇䝍䞊Ⓨ⾲, ᑂᰝ᭷䠅

5) T. Takenaga, M. Goto, M. Hatemura, Y. Uchiyama, S. Katsuragawa, J. Shiraishi, Computer simulation of low-dose clinical CT images, The second International Conference on Radiological Science and Technology, SP021, Japan Hokkaido, October 2014. 䠄ཱྀ㢌Ⓨ

⾲, ᑂᰝ᭷䠅

6) T. Takenaga, M. Goto, M. Hatemura, Y. Uchiyama, S. Katsuragawa, J. Shiraishi, Quality assessment of simulated liw-dose CT image, CSIT, ୰ᅜ ໭ி, August 2013. 䠄ཱྀ㢌Ⓨ⾲, ᑂᰝ᭷䠅

ᅜෆᏛ఍䛻䛚䛡䜛Ⓨ⾲

7) ➉Ọᬛ⨾, ᚋ⸨῟, ෆᒣⰋ୍, ᱇ᕝⱱᙪ, ⓑ▼㡰஧, CT ᳨ᰝ䛻䛚䛡䜛ప㟁ᅽ⏬ീ䝅䝭䝳䝺 䞊䝅䝵䞁䛾ᐇ㦂ⓗヨ䜏, ᪥ᮏᨺᑕ⥺ᢏ⾡Ꮫ఍➨ 43 ᅇ⛅ᏘᏛ⾡኱఍, 10112, ▼ᕝ, 10 ᭶ 2015. 䠄ཱྀ㏙Ⓨ⾲, ᑂᰝ᭷䠅

8) ➉Ọᬛ⨾, ᚋ⸨῟, ⩚ᡭᮧᫀᏹ, ෆᒣⰋ୍, ᱇ᕝⱱᙪ, ⓑ▼㡰஧, ప⥺㔞CT⏬ീ䛾䝅䝭䝳 䝺䞊䝅䝵䞁ᡭἲ䛾⮫ᗋCT⏬ീ䛻䜘䜛ホ౯, ᪥ᮏᨺᑕ⥺ᢏ⾡Ꮫ఍➨71ᅇ⥲఍Ꮫ⾡኱఍, 2071,

⚄ዉᕝ, 4᭶ 2015. 䠄䝰䝙䝍䞊Ⓨ⾲, ᑂᰝ᭷䠅

9) ➉Ọᬛ⨾, ᚋ⸨῟, ⩚ᡭᮧᫀᏹ, ෆᒣⰋ୍, ᱇ᕝⱱᙪ, ⓑ▼㡰஧, CT ⿦⨨䛻䛚䛡䜛 MTF  ᐃ䛾఩⨨౫Ꮡᛶ 䇷Wireἲ䛸Edgeἲ䛾ẚ㍑䇷, ་⏝⏬ീ᝟ሗᏛ఍䠄MII䠅ᖹᡂ26ᖺᗘᖺḟ 䠄➨169ᅇ䠅኱఍, C1, ⇃ᮏ, 5᭶ 2014. 䠄ཱྀ㢌Ⓨ⾲, ᑂᰝ᭷䠅

10) T. Takenaga, M. Goto, M. Hatemura, Y. Uchiyama, S. Katsuragawa, J. Shiraishi,, Computerized simulation of low-dose CT images: Comparison of image quality for different phantoms, ᪥ᮏᨺᑕ⥺ᢏ⾡Ꮫ఍➨70ᅇ⥲఍Ꮫ⾡኱఍, 10207, ⚄ዉᕝ, 4᭶ 2014. 䠄ཱྀ㢌Ⓨ

⾲, ᑂᰝ᭷䠅

11) ➉Ọᬛ⨾, ᚋ⸨῟, ⩚ᡭᮧᫀᏹ, ෆᒣⰋ୍, ᱇ᕝⱱᙪ, ⓑ▼㡰஧, CT ⏬ീ䛻䛚䛡䜛෇ᙧ 䜶䝑䝆ἲ䜢⏝䛔䛯 MTF ィ  䇷䝻䝆䝇䝔䜱䝑䜽㛵ᩘ㏆ఝ䛻䜘䜛䝜䜲䝈㝖ཤ䇷, ᪥ᮏᨺᑕ⥺ᢏ⾡Ꮫ