摘要:

AbstractMR tracking of a vascular guidewire sized for a .035‐inch (.89‐mm) catheter lumen was performed. The guidewire was actively tracked by incorporation of a miniature radiofrequency (RF) receive coil built into its tip. After in vitro validation, simultaneous tracking of the guidewire and a catheter was performed in the aortic and abdominal vessels of a swine at 1.5 T. The ability to track such a small device and the ability to simultaneously track multiple devices are significant steps towards vascular interventions under MR guida

ISSN:1053-1807    

DOI:10.1002/jmri.1880080142

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1998

数据来源: WILEY

摘要:

AbstractFunctional MRI (fMRI) methods have been demonstrated to noninvasively identify motor‐sensory, visual, and other areas of eloquent cortex for guiding surgical intervention. Typically, fMRI data are acquired preoperatively during a conventional surgical planning MRI examination. Unlike direct cortical stimulation at the time of surgery, however, preoperative fMRI methods do not account for the potential movement of tissues (relative to the time of functional imaging) that may occur in the surgical suite as a direct result of the intervention. Recently, an MRI device has been demonstrated for use in the surgical suite that has the potential to reduce the extent of cortical exposure required for the intervention. However, the invasive requirements of cortical mapping may supersede the invasive requirements of the surgical intervention itself. Consequently, we demonstrate here a modification to the intraoperative MRI device that facilitates a noninvasive, real‐time, functional MR examination in the surgical su

ISSN:1053-1807    

DOI:10.1002/jmri.1880080143

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1998

数据来源: WILEY

摘要:

AbstractThe tools and devices used for patient treatment during interventional procedures must be accurately and safely localized. Recently, procedure guidance has been performed increasingly with MRI, but tool localization has been performed primarily by analyzing the lack of signal caused by displaced excited tissue and/or susceptibility artifacts. In this investigation, a new technique was developed to actively detect and visualize interventional tools using receive coils mounted on the tip of the interventional devices. Unlike earlier methods, in which images from small devicemounted coils are superimposed on a previously acquired image data set, our localization method uses similar tip‐mounted tools in combination with a radiofrequency (RF) switching circuit, standard imaging coils, and specially modified sequences to toggle between the standard and tipmounted receive coil within a single fluoroscopic mode sequence. With this technique, the misregistration between the reported anatomic location and true location of interventional devices is minimize

ISSN:1053-1807    

DOI:10.1002/jmri.1880080144

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1998

数据来源: WILEY

摘要:

AbstractTo rapidly track invasive devices within MRI systems, a novel approach using a limited projection reconstruction technique is presented. Our method exploits the difference between images reconstructed from a limited number of projections and serves to depict the tip of a needle during its advancement. This method was implemented on a standard MRI system with a radial fast‐spin‐echo sequence and examined in phantom studies. We demonstrated that the proposed method could track the tip every 300 msec and the tip depicted by the present technique was consistently displaced along the needle by a small distance (5

ISSN:1053-1807    

DOI:10.1002/jmri.1880080145

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1998

数据来源: WILEY

ISSN:1053-1807    

DOI:10.1002/jmri.1880080146

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1998

数据来源: WILEY

ISSN:1053-1807    

DOI:10.1002/jmri.1880080101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1998

数据来源: WILEY