Limits...
MR fluoroscopy in vascular and cardiac interventions (review).

Saeed M, Hetts SW, English J, Wilson M - Int J Cardiovasc Imaging (2011)

Bottom Line: Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures.At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions.MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94107-1701, USA. Maythem.Saeed@radiology.UCSF.edu

ABSTRACT
Vascular and cardiac disease remains a leading cause of morbidity and mortality in developed and emerging countries. Vascular and cardiac interventions require extensive fluoroscopic guidance to navigate endovascular catheters. X-ray fluoroscopy is considered the current modality for real time imaging. It provides excellent spatial and temporal resolution, but is limited by exposure of patients and staff to ionizing radiation, poor soft tissue characterization and lack of quantitative physiologic information. MR fluoroscopy has been introduced with substantial progress during the last decade. Clinical and experimental studies performed under MR fluoroscopy have indicated the suitability of this modality for: delivery of ASD closure, aortic valves, and endovascular stents (aortic, carotid, iliac, renal arteries, inferior vena cava). It aids in performing ablation, creation of hepatic shunts and local delivery of therapies. Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures. At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions. It also provides information on vascular flow and cardiac morphology, function, perfusion and viability. MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

Show MeSH

Related in: MedlinePlus

Selected MR fluoroscopic images show the passive a, b and active c, d catheters in the left ventricle hitting myocardial targets (arrows). The passive catheter is labeled with MR contrast media, while the active catheter wrapped with coil. Note that the background anatomy of the heart and great vessels can be clearly visualized using both the active catheter and active body coil (d)
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3275732&req=5

Fig3: Selected MR fluoroscopic images show the passive a, b and active c, d catheters in the left ventricle hitting myocardial targets (arrows). The passive catheter is labeled with MR contrast media, while the active catheter wrapped with coil. Note that the background anatomy of the heart and great vessels can be clearly visualized using both the active catheter and active body coil (d)

Mentions: Investigators used three approaches for endovascular catheter tracking and navigation, namely passive tracking (Fig. 3), active tracking (Figs. 2, 3) and magnetic catheter steering (Fig. 4). Investigators also used dysprosium markers mounted on 3F non-braided catheters for tracking and visualizing the catheters. The contrast between the catheter and background blood can be improved by injecting MR contrast media, which prevents flow artifacts because the steady state is reached earlier [54, 68]. Bakker et al. [24] were the first to use the passive tracking approach for steering basilica veins of healthy volunteers. Later, this passive approach was adapted by Manke et al. [69] and Razavi et al. in patients [70]. The advantage of this technique is that it requires no hardware or instrument modifications and, thus, appears to be particularly promising in terms of potential clinical applications. The disadvantage is that the catheter disappears when it is out of the image plane due to the motion.Fig. 3


MR fluoroscopy in vascular and cardiac interventions (review).

Saeed M, Hetts SW, English J, Wilson M - Int J Cardiovasc Imaging (2011)

Selected MR fluoroscopic images show the passive a, b and active c, d catheters in the left ventricle hitting myocardial targets (arrows). The passive catheter is labeled with MR contrast media, while the active catheter wrapped with coil. Note that the background anatomy of the heart and great vessels can be clearly visualized using both the active catheter and active body coil (d)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3275732&req=5

Fig3: Selected MR fluoroscopic images show the passive a, b and active c, d catheters in the left ventricle hitting myocardial targets (arrows). The passive catheter is labeled with MR contrast media, while the active catheter wrapped with coil. Note that the background anatomy of the heart and great vessels can be clearly visualized using both the active catheter and active body coil (d)
Mentions: Investigators used three approaches for endovascular catheter tracking and navigation, namely passive tracking (Fig. 3), active tracking (Figs. 2, 3) and magnetic catheter steering (Fig. 4). Investigators also used dysprosium markers mounted on 3F non-braided catheters for tracking and visualizing the catheters. The contrast between the catheter and background blood can be improved by injecting MR contrast media, which prevents flow artifacts because the steady state is reached earlier [54, 68]. Bakker et al. [24] were the first to use the passive tracking approach for steering basilica veins of healthy volunteers. Later, this passive approach was adapted by Manke et al. [69] and Razavi et al. in patients [70]. The advantage of this technique is that it requires no hardware or instrument modifications and, thus, appears to be particularly promising in terms of potential clinical applications. The disadvantage is that the catheter disappears when it is out of the image plane due to the motion.Fig. 3

Bottom Line: Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures.At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions.MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94107-1701, USA. Maythem.Saeed@radiology.UCSF.edu

ABSTRACT
Vascular and cardiac disease remains a leading cause of morbidity and mortality in developed and emerging countries. Vascular and cardiac interventions require extensive fluoroscopic guidance to navigate endovascular catheters. X-ray fluoroscopy is considered the current modality for real time imaging. It provides excellent spatial and temporal resolution, but is limited by exposure of patients and staff to ionizing radiation, poor soft tissue characterization and lack of quantitative physiologic information. MR fluoroscopy has been introduced with substantial progress during the last decade. Clinical and experimental studies performed under MR fluoroscopy have indicated the suitability of this modality for: delivery of ASD closure, aortic valves, and endovascular stents (aortic, carotid, iliac, renal arteries, inferior vena cava). It aids in performing ablation, creation of hepatic shunts and local delivery of therapies. Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures. At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions. It also provides information on vascular flow and cardiac morphology, function, perfusion and viability. MR fluoroscopy has the potential to form the basis for minimally invasive image-guided surgeries that offer improved patient management and cost effectiveness.

Show MeSH
Related in: MedlinePlus