医用画像情報学会雑誌
Online ISSN : 1880-4977
Print ISSN : 0910-1543
ISSN-L : 0910-1543
27 巻, 4 号
選択された号の論文の16件中1~16を表示しています
企画特集号 「21世紀の診断と治療に関わる画像技術, 次の10年の進歩は?」
特別講演資料
論文
  • 檜垣 徹, 金田 和文, 波多 伸彦
    2010 年 27 巻 4 号 p. 105-110
    発行日: 2010年
    公開日: 2010/11/22
    ジャーナル フリー
    In this paper, we propose a registration method for cardiac CT and SPECT. There are fewer correlations between CT and SPECT. Hence it is difficult to register CT to SPECT directly by referencing pixel values. Consequently we propose 2-step registration method using model data which is called “Atlas data". Atlas data has two kinds of information, the first one is normalized SPECT data which is made by averaging some of patient's SPECT. The other is cardiac anatomical data. They include a long and short axes of left ventricle. In the first step of 2-step registration, CT and atlas data are aligned. User needs to set up the axis that is the same as that of atlas data. When it is set, the alignment problem of CT and atlas is solved easily because it just transforms CT axes onto atlas axes. In the second step of the registration, atlas data is aligned to SPECT. In this step, we use general registration method that uses correlation coefficient as metric, and rigid transformation as transformation. Through these steps, CT images are registered to SPECT images via atlas. All case of experimental registration worked well for diagnosis of ischemic heart disease.
  • 金澤 裕樹, 宮地 利明, 八木 絢子, 吉田 彩, 佐藤 修
    2010 年 27 巻 4 号 p. 111-115
    発行日: 2010年
    公開日: 2010/11/22
    ジャーナル フリー
    The purpose of our study is to develop and to assess a method to calculate T1 and T2 relaxation times using fast spin-echo (FSE) sequences with two echoes per excitation. On a 1.5-T MRI, dual-echo FSE sequences with different repetition times (TR:TR2=2TR1, i.e., TR1=400ms and TR2=800ms) were performed in MnCl2 phantom. Then, we assessed effects of the echo train length (ETL) , effective echo time (TE) , and T2 correction for T1 measurement, when changed each imaging parameter. Besides, we evaluated with comparison between the dual-echo FSE method and mixed sequence. With optimizing FSE imaging parameters, i.e., effective TE, TR, and low ETL, the measurement values of T1 and T2 revealed significantly higher correlation between the dual FSE method and mixed sequence. Moreover, the T2 correction to calculate T1 value could be omitted by shortening first effective TE. The dual-echo FSE method makes it possible to measure T1 and T2 fast and easily and to obtain more detailed information of organizations in human.
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