PURPOSE: To examine the feasibility of simultaneous MR real-time active tip tracking and near real-time depiction of the vascular anatomy for percutaneous angioplasty of iliac arteries under MR guidance. MATERIALS AND METHODS: Nine surgically created stenoses of external iliac arteries in pigs were dilated with MR-compatible balloon catheters (Cordis, Roden, The Netherlands). These catheters were equipped with a microcoil for active tracking of the catheter tip with an in-plane update rate of 10 positions per second. The procedures were performed on an interventional 1.5 T Gyroscan ACS-NT scanner (Philips, Best, The Netherlands). Real-time calculation of images acquired by radial k-space filling was performed on a specially designed backprojector exploiting the sliding window reconstruction technique (Philips Research Laboratories, Hamburg, Germany). The image update rate was 20 frames per second using a radial gradient-echo technique (TR = 12 msec, TE = 3.3 msec, 300 radials). MR angiography and X-ray digital subtraction angiography on the X-ray system positioned in-line next to the interventional MR system served as control for the angioplasty results. RESULTS: Real-time guidance and positioning of the balloon catheters was possible. The actual position of the catheter tip was indicated in the MR images without any time delay for the reconstruction of the anatomical MR images, which were updated with a rate of 20 frames per second. This yielded a combination of a roadmap and fluoroscopy image, in which the catheter position and the anatomical background image both were continuously updated in real time. Six out of nine stenoses were successfully dilated. The effects of the angioplasty could be visualized by the real-time MR technique, as was proven by X-ray digital subtraction angiography. CONCLUSION: Active tip tracking simultaneous with MRI of the vascular anatomy-both in real time-is possible with the applied technique, enabling MR-guided percutaneous dilatation (PTA) of iliac arteries. Copyright 2002 Wiley-Liss, Inc.
PURPOSE: To examine the feasibility of simultaneous MR real-time active tip tracking and near real-time depiction of the vascular anatomy for percutaneous angioplasty of iliac arteries under MR guidance. MATERIALS AND METHODS: Nine surgically created stenoses of external iliac arteries in pigs were dilated with MR-compatible balloon catheters (Cordis, Roden, The Netherlands). These catheters were equipped with a microcoil for active tracking of the catheter tip with an in-plane update rate of 10 positions per second. The procedures were performed on an interventional 1.5 T Gyroscan ACS-NT scanner (Philips, Best, The Netherlands). Real-time calculation of images acquired by radial k-space filling was performed on a specially designed backprojector exploiting the sliding window reconstruction technique (Philips Research Laboratories, Hamburg, Germany). The image update rate was 20 frames per second using a radial gradient-echo technique (TR = 12 msec, TE = 3.3 msec, 300 radials). MR angiography and X-ray digital subtraction angiography on the X-ray system positioned in-line next to the interventional MR system served as control for the angioplasty results. RESULTS: Real-time guidance and positioning of the balloon catheters was possible. The actual position of the catheter tip was indicated in the MR images without any time delay for the reconstruction of the anatomical MR images, which were updated with a rate of 20 frames per second. This yielded a combination of a roadmap and fluoroscopy image, in which the catheter position and the anatomical background image both were continuously updated in real time. Six out of nine stenoses were successfully dilated. The effects of the angioplasty could be visualized by the real-time MR technique, as was proven by X-ray digital subtraction angiography. CONCLUSION: Active tip tracking simultaneous with MRI of the vascular anatomy-both in real time-is possible with the applied technique, enabling MR-guided percutaneous dilatation (PTA) of iliac arteries. Copyright 2002 Wiley-Liss, Inc.
Authors: George Rappard; Gregory J Metzger; James L Fleckenstein; Evelyn E Babcock; Paul T Weatherall; Robert E Replogle; G Lee Pride; Susan L Miller; Christina E Adams; Phillip D Purdy Journal: AJNR Am J Neuroradiol Date: 2003-04 Impact factor: 3.825
Authors: Amish N Raval; Parag V Karmarkar; Michael A Guttman; Cengizhan Ozturk; Ranil Desilva; Ronnier J Aviles; Victor J Wright; William H Schenke; Ergin Atalar; Elliot R McVeigh; Robert J Lederman Journal: Catheter Cardiovasc Interv Date: 2006-04 Impact factor: 2.692
Authors: Amish N Raval; James D Telep; Michael A Guttman; Cengizhan Ozturk; Michael Jones; Richard B Thompson; Victor J Wright; William H Schenke; Ranil DeSilva; Ronnier J Aviles; Venkatesh K Raman; Michael C Slack; Robert J Lederman Journal: Circulation Date: 2005-07-25 Impact factor: 29.690
Authors: Philipp Kahlert; Holger Eggebrecht; Björn Plicht; Oliver Kraff; Ian McDougall; Brad Decker; Raimund Erbel; Mark E Ladd; Harald H Quick Journal: J Cardiovasc Magn Reson Date: 2010-10-13 Impact factor: 5.364