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Quantitative characterizations of ultrashort echo (UTE) images for supporting air–bone separation in the head

Shu-Hui Hsu, Yue Cao, Theodore S Lawrence, Christina Tsien, Mary Feng, David M Grodzki, James M Balter
2015 Physics in Medicine and Biology  
The two MRI sequences tested were ultra-short TE imaging using 3D radial acquisition (UTE), and using pointwise encoding time reduction with radial acquisition (PETRA).  ...  Receiver operating characteristic (ROC) analyses, by comparing predicted (defined by MR images) versus "true" regions of air and bone (defined by CT images), were performed with and without residual bias  ...  This work was supported by NIH EB016079 and a grant from Siemens Medical Systems.  ... 
doi:10.1088/0031-9155/60/7/2869 pmid:25776205 pmcid:PMC4405190 fatcat:orybv4aapvgdphh5afmtiu4ypa

MRI-Only Based Radiotherapy Treatment Planning for the Rat Brain on a Small Animal Radiation Research Platform (SARRP)

Shandra Gutierrez, Benedicte Descamps, Christian Vanhove, Heye Zhang
2015 PLoS ONE  
The MR sequences were: T1-weighted, T2-weighted, zero-echo time (ZTE), and two ultra-short echo time sequences with 20 μs (UTE1) and 2 ms (UTE2) echo times.  ...  Six rat heads were imaged, each with one CT and five MR sequences.  ...  In addition to these structural images, three other MR sequences were acquired, including an ultra-short echo time sequence with 20μs echo time (UTE1), an ultra-short echo time sequence with 2ms echo time  ... 
doi:10.1371/journal.pone.0143821 pmid:26633302 pmcid:PMC4669183 fatcat:rw6usyb2qfexdinsh6gkq7pb3e

Advances in MRI of the myelin bilayer

Markus Weiger, Romain Froidevaux, Emily Louise Baadsvik, David Otto Brunner, Manuela Barbara Rösler, Klaas Paul Pruessmann
2020 NeuroImage  
In the present work, capture and encoding of the ultra-short-T2 signals in the myelin bilayer is considerably improved by employing advanced short-T2 methodology and hardware, in particular a high-performance  ...  However, MRI of the lipid bilayer constituting the myelin membrane is hampered by extremely rapid signal decay and cannot be accomplished with conventional sequences.  ...  In the short-T 2 * -enhanced subtraction image (Fig. 9c) , prominent signal is observed from the skull, the skin, and the ear muffs.  ... 
doi:10.1016/j.neuroimage.2020.116888 pmid:32360688 fatcat:ohgizzrzrjgsxgohtp4mfg2xmy

Investigation of a method for generating synthetic CT models from MRI scans of the head and neck for radiation therapy

Shu-Hui Hsu, Yue Cao, Ke Huang, Mary Feng, James M Balter
2013 Physics in Medicine and Biology  
The method consists of (1) acquiring multiple MRI volumes: T1-weighted, T2-weighted, two echoes from a ultra-short TE (UTE) sequence, and calculated fat and water image volumes using a Dixon method, (2  ...  For one prospective patient, the correlation of skull intensities between CT and MR was investigated, the discriminatory power of MRI in separating air from bone was evaluated, and the generated MRCT image  ...  Acknowledgments We wish to thank Siemens Medical Systems for providing a prototype UTE sequence for this investigation. This work was supported in part by NIH EB016079.  ... 
doi:10.1088/0031-9155/58/23/8419 pmid:24217183 pmcid:PMC3886820 fatcat:7j5g2lxlzfd47irjgp44ljcaqu

Learning-based single-step quantitative susceptibility mapping reconstruction without brain extraction

Hongjiang Wei, Steven Cao, Yuyao Zhang, Xiaojun Guan, Fuhua Yan, Kristen W. Yeom, Chunlei Liu
2019 NeuroImage  
To address these challenges, we propose a learning-based QSM reconstruction method that directly estimates the magnetic susceptibility from total phase images without the need for brain extraction and  ...  The neural network has a modified U-net structure and is trained using QSM maps computed by a two-step QSM method. 209 healthy subjects with ages ranging from 11 to 82 years were employed for patch-wise  ...  Acknowledgements This study is supported in part by the National Institutes of Health through grants NIMH R01MH096979 and U01EB025162. We thank Woojin Jung and Prof.  ... 
doi:10.1016/j.neuroimage.2019.116064 pmid:31377323 pmcid:PMC6819263 fatcat:tayob7wnlzgbpbi7ozur4kt5xy

Pseudo-CT Generation for External Radiotherapy Planning from Magnetic Resonance Imaging Data on Brain Regions

Niloofar Yousefi Moteghaed, Ali Yaghobi Joybari, Ahmad Mostaar
2019 Iranian Journal of Radiology  
Conclusion: The proposed method generated pseudo-CT images from different segmented parts of the brain of MRI series. The application requires segmentation of the cortical bones in MR images.  ...  Materials and Methods: The pseudo-CT images were generated for 10 randomly chosen patients with brain disease.  ...  Funding/Support: This study was funded and supported by Shahid Beheshti University of Medical Sciences (SBMU).  ... 
doi:10.5812/iranjradiol.82804 fatcat:bm7tgb7tpbd37k4odm7kyeywv4

Silent Zero TE MR Neuroimaging: Current State-of-the-Art and Future Directions

Emil Ljungberg, Nikou L. Damestani, Tobias C. Wood, David J. Lythgoe, Fernando Zelaya, Steven C.R. Williams, Ana Beatriz Solana, Gareth J. Barker, Florian Wiesinger
2021 Progress in nuclear magnetic resonance spectroscopy  
a nominal echo time of TE = 0 (thus capturing short-lived signals from MR tissues which are otherwise MR-invisible), 3D radial sampling (providing motion robustness), and ultra-short repetition times  ...  Magnetic Resonance Imaging (MRI) scanners produce loud acoustic noise originating from vibrational Lorentz forces induced by rapidly changing currents in the magnetic field gradient coils.  ...  We want to acknowledge that the spin coherence diagrams in Figs. 5 and 6 were inspired by Fig. 1 in Ref. [70] .  ... 
doi:10.1016/j.pnmrs.2021.03.002 pmid:34078538 fatcat:mh3sp3fbdrdlllj6lzi5tcwiaq

Fast frequency-sweep spectroscopic imaging with an ultra-low flip angle

Junyu Guo, Zoltan Patay, Wilburn E. Reddick
2016 Scientific Reports  
PCSI uses a balanced steady-state free precession (bSSFP) sequence with an ultra-low flip angle to achieve very high acquisition efficiency with a short repetition time.  ...  The lipid signal in the skull has to be suppressed to prevent it from contaminating the spectra obtained inside the brain.  ...  Acknowledgements This work was supported in part by Cancer Center Support Grant P30 CA-21765 from the National Cancer Institute at the National institutes of Health, Bethesda, MD, and by ALSAC, Memphis  ... 
doi:10.1038/srep30066 pmid:27440077 pmcid:PMC4954958 fatcat:j3ircbj6t5glvdqhpypfnnmwsm

Region specific optimization of continuous linear attenuation coefficients based on UTE (RESOLUTE): application to PET/MR brain imaging

Claes N Ladefoged, Didier Benoit, Ian Law, Søren Holm, Andreas Kjær, Liselotte Højgaard, Adam E Hansen, Flemming L Andersen
2015 Physics in Medicine and Biology  
Acknowledgments The PET/MR system was donated by the John and Birthe Meyer Foundation. We thank Dr Gillings for linguistic corrections.  ...  The ultra-short echo time (UTE) MR sequence (Robson et al 2003) was proposed for MR-AC to account for the bias introduced by ignoring the bone (Catana et al 2010) .  ...  The UTE sequence consists of a pair of MR images obtained at an ultra-short echo time, where a signal can be obtained in bone, and a later echo time, where the bone signal has fully decayed.  ... 
doi:10.1088/0031-9155/60/20/8047 pmid:26422177 fatcat:beg4522xirb2zismpgq2zoerre

Multi-slice passband bSSFP fMRI at ultra-high field [article]

Olivier Reynaud, Analina R. da Silva, Rolf Gruetter, Ileana O. Jelescu
2018 arXiv   pre-print
Balanced steady-state free precession (bSSFP) can be used as an alternative to gradient-echo (GE) EPI for BOLD functional MRI when image distortions and signal drop-outs are severe such as at ultra-high  ...  However, 3D-bSSFP acquisitions have distinct drawbacks on either human or animal MR systems.  ...  They also acknowledge assistance with animal setup and monitoring from Mario Lepore and Stefan Mitrea.  ... 
arXiv:1812.04395v1 fatcat:4b5vk3f3j5ehno6ncokt4k2xye

A review on methods to estimate a CT from MRI data in the context of MRI-alone RT

Boukellouz Wafa, Abdelouahab Moussaoui
2018 Medical Technologies Journal  
Conclusion: Radiation therapy is emerging towards the generalisation of MRI-only RT thanks to the advances in techniques for generation of pseudo-CT images and the development of specialised MR sequences  ...  In addition, an interest in the Dixon MR sequence is increasing since it has the advantage of producing multiple contrast images with a single acquisition.  ...  In (32) , authors presented a classification approach to generate a pseudo-CT from several MR images such as T1-weighted, T2-weighted, and two echoes from an Ultra-short Echo Time (UTE) sequence.  ... 
doi:10.26415/2572-004x-vol2iss1p150-178 fatcat:g3sfz6haffevlbrsbwhwqt6hye

Post Mortem Validation of MRI-Identified Veins on the Surface of the Cerebral Cortex as Potential Landmarks for Neurosurgery

Günther Grabner, Thomas Haider, Mark Glassner, Alexander Rauscher, Hannes Traxler, Siegfried Trattnig, Simon D. Robinson
2017 Frontiers in Neuroscience  
Imaging data are registered to the patient's skull so that they correspond to the intraoperative macro-and microscopic view.  ...  and Objective: Image-guided neurosurgery uses information from a wide spectrum of methods to inform the neurosurgeon's judgement about which tissue to resect and which to spare.  ...  ST: Medical contribution, MR imaging. SR: Writing, image processing, MR imaging.  ... 
doi:10.3389/fnins.2017.00355 pmid:28680389 pmcid:PMC5478689 fatcat:dwfpdfvj2jgc7oy4xbmlof2gmm

Random forest regression for magnetic resonance image synthesis

Amod Jog, Aaron Carass, Snehashis Roy, Dzung L. Pham, Jerry L. Prince
2017 Medical Image Analysis  
By choosing different pulse sequences and their parameters, magnetic resonance imaging (MRI) can generate a large variety of tissue contrasts.  ...  Although image synthesis of MR images has been shown to be helpful in addressing this problem, an inability to synthesize both T 2 -weighted brain images that include the skull and FLuid Attenuated Inversion  ...  Acknowledgments This work was supported by the NIH/NIBIB under grant R21 EB012765 and R01 EB017743, and by the NIH/ NINDS through grant R01 NS070906.  ... 
doi:10.1016/ pmid:27607469 pmcid:PMC5099106 fatcat:dm4njm3gl5c53p4dl6vpx6vuf4

Contribution of Susceptibility-Weighted Imaging to Acute Stroke Assessment

M. Hermier, N. Nighoghossian
2004 Stroke  
We report on the use of SW imaging (SWI) sequences in clinical practice and highlight the future applications.  ...  Summary of Review-SWI exploits the magnetic susceptibility effects generated by local inhomogeneities of the magnetic field.  ...  generated by the paranasal sinuses and the skull base.  ... 
doi:10.1161/01.str.0000133341.74387.96 pmid:15192245 fatcat:x3ex4tswm5afraelepogbxkdha

Preconditioned total field inversion (TFI) method for quantitative susceptibility mapping

Zhe Liu, Youngwook Kee, Dong Zhou, Yi Wang, Pascal Spincemaille
2016 Magnetic Resonance in Medicine  
Moreover, preconditioned TFI was capable of generating QSM for the entire head including the brain, air-filled sinus, skull, and fat.  ...  Theory and Methods-The proposed TFI is a single optimization problem which simultaneously estimates the background and local fields, preventing error propagation from background field removal to QSM.  ...  Third, for whole head QSM, the skull has very short T2 * , such that the multi-echo GRE sequence fails to acquire skull MR signal for field estimation.  ... 
doi:10.1002/mrm.26331 pmid:27464893 pmcid:PMC5274595 fatcat:ezyiqwkwgbhyfocwdobbytlymq
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