研究生: |
王基崇 Chi-chung Wang |
---|---|
論文名稱: |
螺旋槳型編碼之自我運動追踨術:心肌動態磁振造影之應用 Self-gated PROPELLER cine cardiac imaging: Simultaneously tracking the cardiac pulsation and the respiratory motion |
指導教授: |
黃騰毅
Teng-yi Huang |
口試委員: |
林益如
none 劉益瑞 none 柯正雯 none |
學位類別: |
碩士 Master |
系所名稱: |
電資學院 - 電機工程系 Department of Electrical Engineering |
論文出版年: | 2007 |
畢業學年度: | 95 |
語文別: | 英文 |
論文頁數: | 49 |
中文關鍵詞: | 心電圖觸發 、閉氣 、螺旋槳型編碼法 、運動同步 |
外文關鍵詞: | EKG trigger, breath-hold, PROPELLER encoding, motion synchronization |
相關次數: | 點閱:262 下載:4 |
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在心臟磁振造影中為了避免運動假影對成像造成影響,一般的輔助方式是同時採用閉氣以及心電圖觸發。然而在實際臨床應用上,有些病人因為疾病或者年老的關係而無法自主性的閉氣,心電圖觸發系統也常常因為磁振造影儀的磁場影響而必須重複設定。這些都是造成心臟磁振造影比其他身體部位的磁振造影要困難的原因。為了解決這些困難點,在本論文裡提出了一項不需要使用閉氣以及心電圖觸發技術輔助的心臟磁振造影技術。此心臟成像技術是基於螺旋槳型編碼法以及self-gating技術,並適用於大部分以傅立葉轉換為基礎的影像擷取方式。藉由此技術,可以從磁振造影訊號裡擷取出心臟與呼吸運動的同步資料,並將之應用於重建高解析度的心臟動態影像。
In order to reduce motion-related artifacts, breath-holding and EKG trigger is generally required for cardiac MRI. However, in the clinical practice, some patients can not perform voluntary breath-hold and the EKG trigger system sometimes fails due to the interference of magnetic field and gradient system. To solve this problem, a new cardiac imaging technique with the need for EKG trigger and breath-hold, is proposed. This new cardiac imaging technique, which is designed for cine cardiac imaging, is based on self-gating technique with PROPELLER encoding. By this technique, the patient can freely breathe during the scan of cine cardiac imaging. Moreover, the cardiac motion synchronization data can be calculated directly from MRI signal and can apply to retrospective cine cardiac image reconstruction. Therefore, the EKG trigger is not necessary during the scan. This technique is suitable for most FFT-based acquisitions, such as gradient-echo sequences or EPI. Experimental results on a 3.0 Tesla MR system showed that this method can be applied to reconstruct cine cardiac images without prominent artifacts.
1. Lanzer P, Barta C, Botvinick EH, Wiesendanger HU, Modin G, Higgins CB. ECG-synchronized cardiac MR imaging: method and evaluation. Radiology 1985;155(3):681-686.
2. Gatehouse PD, Firmin DN. The cardiovascular magnetic resonance machine: hardware and software requirements. Herz 2000;25(4):317-330.
3. Yuan Q, Axel L, Hernandez EH, et al. Cardiac-respiratory gating method for magnetic resonance imaging of the heart. Magn Reson Med 2000;43(2):314-318.
4. Kim WS, Mun CW, Kim DJ, Cho ZH. Extraction of cardiac and respiratory motion cycles by use of projection data and its applications to NMR imaging. Magn Reson Med 1990;13(1):25-37.
5. Spraggins TA. Wireless retrospective gating: application to cine cardiac imaging. Magnetic resonance imaging 1990;8(6):675-681.
6. Vasanawala SS, Sachs TS, Brittain JH, Meyer CH, Nishimura DG. Prospective MR signal-based cardiac triggering. Magn Reson Med 1999;42(1):82-86.
7. Dimick RN, Hedlund LW, Herfkens RJ, Fram EK, Utz J. Optimizing electrocardiograph electrode placement for cardiac-gated magnetic resonance imaging. Investigative radiology 1987;22(1):17-22.
8. Allen PJ, Polizzi G, Krakow K, Fish DR, Lemieux L. Identification of EEG events in the MR scanner: the problem of pulse artifact and a method for its subtraction. NeuroImage 1998;8(3):229-239.
9. Larson AC, White RD, Laub G, McVeigh ER, Li D, Simonetti OP. Self-gated cardiac cine MRI. Magn Reson Med 2004;51(1):93-102.
10. Larson AC, Kellman P, Arai A, et al. Preliminary investigation of respiratory self-gating for free-breathing segmented cine MRI. Magn Reson Med 2005;53(1):159-168.
11. Pipe JG. Motion correction with PROPELLER MRI: application to head motion and free-breathing cardiac imaging. Magn Reson Med 1999;42(5):963-969.
12. Chuang TC, Huang TY, Lin FH, et al. PROPELLER-EPI with parallel imaging using a circularly symmetric phased-array RF coil at 3.0 T: application to high-resolution diffusion tensor imaging. Magn Reson Med 2006;56(6):1352-1358.
13. Wang FN, Huang TY, Lin FH, et al. PROPELLER EPI: an MRI technique suitable for diffusion tensor imaging at high field strength with reduced geometric distortions. Magn Reson Med 2005;54(5):1232-1240.
14. Jackson JI, Meyer CH, Nishimura DG, Macovski A. Selection of a convolution function for Fourier inversion using gridding [computerised tomography application]. Medical Imaging, IEEE Transactions on 1991;10(3):473-478.
15. Pipe JG, Menon P. Sampling density compensation in MRI: rationale and an iterative numerical solution. Magn Reson Med 1999;41(1):179-186.