Real-Time Liver Motion Compensation for MRgFUS

Ross, James C.; Tranquebar, Rekha; Shanbhag, Dattesh

doi:10.1007/978-3-540-85990-1_97

Cited by 12 publications

(8 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, the underlying regularity constraint (19) that assumes a continuous differentiable motion field was found well suited for elastic targets that display local deformations during the respiratory cycle, such as the liver or the spleen. Compared to Ross et al (28), the implemented approach does not require any landmark identification, and thus the estimated motion field is independent of preceding user interactions or preliminary segmentation steps. Although this approach is computationally intensive and thus challenging to implement for real‐time imaging, the proposed CPU/GPU implementation renders this method compatible with sustained high frame‐rate real‐time imaging.…”

Section: Discussionmentioning

confidence: 99%

Real-time MR-thermometry and dosimetry for interventional guidance on abdominal organs

Roujol¹,

Ries²,

Quesson³

et al. 2010

Magn. Reson. Med.

133

142

View full text Add to dashboard Cite

The use of proton resonance frequency shift-based magnetic resonance (MR) thermometry for interventional guidance on abdominal organs is hampered by the constant displacement of the target due to the respiratory cycle and the associated thermometry artifacts. Ideally, a suitable MR thermometry method should for this role achieve a subsecond temporal resolution while maintaining a precision comparable to those achieved on static organs while not introducing significant processing latencies. Here, a computationally effective processing pipeline for two-dimensional image registration coupled with a multibaseline phase correction is proposed in conjunction with high-frame-rate MRI as a possible solution. The proposed MR thermometry method was evaluated for 5 min at a frame rate of 10 images/sec in the liver and the kidney of 11 healthy volunteers and achieved a precision of less than 2°C in 70% of the pixels while delivering temperature and thermal dose maps on the fly. The ability to perform MR thermometry and dosimetry in vivo during a real intervention was demonstrated on a porcine kidney during a high-intensity focused ultrasound heating experiment. Magn Reson Med 63:1080-1087, 2010. V C 2010 Wiley-Liss, Inc. Key words: MRI; thermometry; temperature; interventional; imaging; real time system; motion artifacts; proton resonance frequency shift; PRF MR thermometry relying on the water proton resonance frequency is gaining importance for monitoring and guiding thermal therapies such as radiofrequency (1), laser (2), or focused ultrasound thermal ablation (3-5). Typically, proton resonance frequency-based MR thermometry relies on the voxelwise evaluation of phase differences between sequentially acquired gradient echo images. However, for the use on abdominal organs, this renders the method very sensitive to motion artifacts and magnetic field changes. These motion artifacts can be coarsely classed into the two following types: intrascan motion artifacts and interscan motion artifacts. Intrascan motion artifacts are caused by displacement during the MR acquisition process and lead to image blurring and object ghosting. Commonly, this type of artifact is addressed using fast MR acquisition schemes or alternatively with respiratory-gated sequences that reduce the temporal resolution to the respiratory frequency. Interscan motion artifacts are due to organ displacement between the MR acquisitions and lead to a misregistration between subsequent phase images and thus to artifacts in the subtraction process. Furthermore, since any displacement or plastic deformation of the abdominal organs will in general also lead to a modified demagnetization field and thus to a change of the local magnetic field (6-8), additional phase artifacts are introduced.To overcome these problems, several correction strategies have been proposed, such as respiratory gating (9), navigator echoes (10), multibaseline acquisition to sample periodic changes (11,12), and referenceless phase corrections (13). Furthermore, the concept of the equivalent...

show abstract

Section: Discussionmentioning

confidence: 99%

Real-time MR-thermometry and dosimetry for interventional guidance on abdominal organs

Roujol¹,

Ries²,

Quesson³

et al. 2010

Magn. Reson. Med.

133

142

View full text Add to dashboard Cite

show abstract

“…34,41,[64][65][66] This strategy has been successfully validated for real time beam steering MRgHIFU experiment. 34 In this scenario, the acquisition, reconstruction and processing of incoming MR-images need to satisfy the real time constraint of the beam steering system and must therefore be performed with minimal overall latency.…”

Section: Direct Motion Estimation Using Mrimentioning

confidence: 94%

“…34,41,65,66 In featurebased approaches, specific vessels that were initially selected manually were automatically tracked during the procedure. 64,69 Although it does not require intensive computation, it may be limited to fully characterize complex motion. Furthermore, the additional vessel deformation induced by the cardiac activity may also bias the overall organ motion estimates.…”

Section: Direct Motion Estimation Using Mrimentioning

confidence: 99%

“…For this purpose, accelerated MR-acquisition schemes combined with efficient graphic processing unit (GPU) based reconstruction 67,68 have been shown to enable online reconstruction of 2D MR images with a high framerate and low latency. 67 Image-based motion estimation of the target can then be performed immediately after the image reconstruction using either featurebased approaches 64,69 or intensity-based approaches. 34,41,65,66 In featurebased approaches, specific vessels that were initially selected manually were automatically tracked during the procedure.…”

Section: Direct Motion Estimation Using Mrimentioning

confidence: 99%

See 1 more Smart Citation

Motion Correction Techniques for MR-Guided HIFU Ablation of Abdominal Organs

Roujol

Moonen

2014

Frontiers of Medical Imaging

View full text Add to dashboard Cite

Magnetic resonance guided high intensity focused ultrasound (MRgHIFU) ablation is a promising technique for the treatment of hepatic and renal cancers. In this approach, the HIFU system is used for ablating the tumor using local heating while the MRI scanner provides online temperature measurements which enable continuous monitoring of the delivered thermal dose. The application of MRgHIFU ablation for abdominal organs is challenging. Many technical developments have addressed the major issues associated with this procedure such as the physiological motion of abdominal organs. In this chapter, we present the different techniques which have been developed to alleviate the problem of physiological motion for MRgHIFU ablation of abdominal organs.

show abstract

“…In minimally invasive surgery, the methods are mainly based on the use of intraoperative imaging and tracking systems [8][9][10]. One solution to the deformation produced by the movement of the organ was described by Zhang et al [11], who compensate organ motion using an electromagnetic tracking system.…”

Section: Mental Map and Navigationmentioning

confidence: 99%

Untitled

2012

IJBB

View full text Add to dashboard Cite

show abstract

Real-Time Liver Motion Compensation for MRgFUS

Cited by 12 publications

References 9 publications

Real-time MR-thermometry and dosimetry for interventional guidance on abdominal organs

Real-time MR-thermometry and dosimetry for interventional guidance on abdominal organs

Motion Correction Techniques for MR-Guided HIFU Ablation of Abdominal Organs

Untitled

Contact Info

Product

Resources

About