scholarly journals Pulmonary Embolism Detection with Three-dimensional Ultrashort Echo Time MR Imaging: Experimental Study in Canines

Radiology ◽  
2016 ◽  
Vol 278 (2) ◽  
pp. 413-421 ◽  
Author(s):  
Peter Bannas ◽  
Laura C. Bell ◽  
Kevin M. Johnson ◽  
Mark L. Schiebler ◽  
Christopher J. François ◽  
...  
Keyword(s):  
Experimental Study ◽  
Pulmonary Embolism ◽  
Mr Imaging ◽  
Three Dimensional ◽  
Ultrashort Echo Time ◽  
Echo Time

scholarly journals A Useful Combination of Quantitative Ultrashort Echo Time MR Imaging and a Probing Device for Biomechanical Evaluation of Articular Cartilage

Biosensors ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 52
Author(s):  
Takehito Hananouchi ◽  
Yanjun Chen ◽  
Saeed Jerban ◽  
Masaru Teramoto ◽  
Yajun Ma ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mr Imaging ◽  
Linear Regression Analysis ◽  
Reaction Force ◽  
Predictor Variable ◽  
Cartilage Tissue ◽  
Magnetization Transfer Ratio ◽  
Ultrashort Echo Time ◽  
Echo Time

In this study, we combined quantitative ultrashort echo time (UTE) magnetic resonance (MR) imaging and an investigation by a probing device with tri-axial force sensor to seek correlations with mechanical properties of human patellar cartilage for in situ evaluation of biomechanical properties. Cartilage blocks (15 × 20 × 5 mm3) were dissected from the patella of six donors; 5 mm square regions of interest from the cartilage blocks were imaged using UTE-MR imaging sequences (T2* and magnetization transfer ratio (MTR)), and mechanical properties were measured using a micro indentation device. Then, the vertical reaction force on the cartilage surface was measured while push-probing forward 3 mm with the probing device at a 30° tilt to the horizontal plane. The results showed a positive correlation between stiffness/elastic modulus and each predictor variable (UTE-T2* (r = 0.240 and 0.255, respectively, UTE-MTR (r = 0.378 and 0.379, respectively), and probing device force (r = 0.426 and 0.423, respectively). Furthermore, multiple linear regression analysis showed the combination of the three predictors had stronger correlation (adjusted r2 = 0.314 (stiffness), 0.323 (elastic), respectively). Our results demonstrate the potential for these non- and less- invasive methods for in situ evaluation of the mechanical properties of cartilage tissue.

Three-dimensional ultrashort echo time cones (3D UTE-Cones) magnetic resonance imaging of entheses and tendons

2018 ◽  
Vol 49 ◽  
pp. 4-9 ◽  
Author(s):  
Bimin Chen ◽  
Yinghua Zhao ◽  
Xin Cheng ◽  
Yajun Ma ◽  
Eric Y. Chang ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Three Dimensional ◽  
Resonance Imaging ◽  
Ultrashort Echo Time ◽  
Echo Time

scholarly journals Volumetric mapping of bound and pore water as well as collagen protons in cortical bone using 3D ultrashort echo time cones MR imaging techniques

Bone ◽  
2019 ◽  
Vol 127 ◽  
pp. 120-128 ◽  
Author(s):  
Saeed Jerban ◽  
Yajun Ma ◽  
Liang Li ◽  
Hyungseok Jang ◽  
Lidi Wan ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Cortical Bone ◽  
Pore Water ◽  
Imaging Techniques ◽  
Ultrashort Echo Time ◽  
Echo Time

Three-Dimensional Ultrashort Echo Time Imaging of Solid Polymers on a 3-Tesla Whole-Body MRI Scanner

2008 ◽  
Vol 43 (11) ◽  
pp. 802-808 ◽  
Author(s):  
Fabian Springer ◽  
Petros Martirosian ◽  
Nina F. Schwenzer ◽  
Michael Szimtenings ◽  
Peter Kreisler ◽  
...  
Keyword(s):  
Three Dimensional ◽  
3 Tesla ◽  
Whole Body ◽  
Ultrashort Echo Time ◽  
Whole Body Mri ◽  
Solid Polymers ◽  
Echo Time

Exponential subtraction in 3D ultrashort echo time imaging to visualize short T2 tissues in tibia

2019 ◽  
Vol 61 (6) ◽  
pp. 760-767
Author(s):  
Sha Li ◽  
Xinrui Huang ◽  
Guozhen Li ◽  
Yibao Zhang ◽  
Zhaotong Li ◽  
...  
Keyword(s):  
Cortical Bone ◽  
Three Dimensional ◽  
Regions Of Interest ◽  
Observer Agreement ◽  
Exponential Factor ◽  
Ultrashort Echo Time ◽  
Short T2 ◽  
Exponential Factors ◽  
Echo Time ◽  
Dual Echo

Background Short T2 tissues can be directly visualized by dual-echo ultrashort echo time imaging with weighted subtraction. As a type of post-processing method, exponential subtraction of ultrashort echo time images with an optimal exponential factor is expected to provide improved positive short T2 contrast. Purpose To test the feasibility and effectiveness of exponential subtraction in three-dimensional ultrashort echo time imaging and to determine the optimal exponential factor. Material and Methods A dual-echo three-dimensional ultrashort echo time sequence was implemented on a 3-T MRI system. Exponential subtraction was performed on dual three-dimensional ultrashort echo time images of the tibia of seven healthy volunteers with exponential factors in the range of 1.00–3.00 in increments of 0.01. The regions of interest, including cortical bone, marrow, and muscle, were depicted on subtracted images of different exponential factors. Contrast-to-noise ratio values were calculated from these regions of interest and then used to assess the optimal exponential factor. To determine intra-observer agreement regarding region of interest selection, paired intra-observer measurements of regions of interest in all direct subtraction images were conducted with a one-week interval and the paired measurements were assessed using Bland–Altman analysis and paired-samples t-test. Results Cortical bone can be better visualized by using exponential subtraction in three-dimensional ultrashort echo time imaging; the suggested optimal exponential factor is 1.99–2.03 in the tibia. Paired measurements showed excellent intra-observer agreement. Conclusion It is feasible to visualize cortical bone of the tibia using exponential subtraction in three-dimensional ultrashort echo time imaging. Compared with weighted subtraction images, exponential subtraction images with an optimal exponential factor provide enhanced visualization of short T2 tissues.

scholarly journals Magnetic Resonance Imaging of Hard Tissues and Hard Tissue Engineered Bio-substitutes

2019 ◽  
Vol 21 (6) ◽  
pp. 1003-1019 ◽  
Author(s):  
Simone Mastrogiacomo ◽  
Weiqiang Dou ◽  
John A. Jansen ◽  
X. Frank Walboomers
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Resonance Imaging ◽  
Hard Tissue ◽  
Comprehensive Overview ◽  
Ultrashort Echo Time ◽  
Dental Tissues ◽  
Hard Tissues ◽  
Echo Time

Abstract Magnetic resonance imaging (MRI) is a non-invasive diagnostic imaging tool based on the detection of protons into the tissues. This imaging technique is remarkable because of high spatial resolution, strong soft tissue contrast and specificity, and good depth penetration. However, MR imaging of hard tissues, such as bone and teeth, remains challenging due to low proton content in such tissues as well as to very short transverse relaxation times (T2). To overcome these issues, new MRI techniques, such as sweep imaging with Fourier transformation (SWIFT), ultrashort echo time (UTE) imaging, and zero echo time (ZTE) imaging, have been developed for hard tissues imaging with promising results reported. Within this article, MRI techniques developed for the detection of hard tissues, such as bone and dental tissues, have been reviewed. The main goal was thus to give a comprehensive overview on the corresponding (pre-) clinical applications and on the potential future directions with such techniques applied. In addition, a section dedicated to MR imaging of novel biomaterials developed for hard tissue applications was given as well.

Sign in / Sign up

Export Citation Format

Share Document