The use of on-resonance 121 binomial composite pulses in two- or three-dimensional magnetization-prepared gradient-recalled echo magnetic resonance imaging experiments generates rotary echoes, leading to an increase in contrast range that is, in part, determined by the ratio of T2 to T1. In comparison with other fast gradient-recalled echo imaging techniques designed for enhanced T2 contrast, this method is more robust with respect to radiofrequency field inhomogeneity and less sensitive with respect to motion artifacts. Three-dimensional parametric images may be calculated using least-squares fitting based on a simple model for steady-state longitudinal magnetization during the imaging sequences.
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http://dx.doi.org/10.1007/BF02594582 | DOI Listing |
Insights Imaging
January 2025
Diagnostic and Interventional Radiology, University Hospital of Zurich, University Zurich, Zurich, Switzerland.
Objectives: To compare and correlate bone edema volume detected by 3D-short-tau-inversion-recovery (STIR) sequence to osseous decay detected by a T1-based sequence and conventional panoramic radiography (OPT).
Materials And Methods: Patients with clinical evidence of apical periodontitis were included retrospectively and received OPT as well as MRI of the viscerocranium including a 3D-STIR and a 3D-T1 gradient echo sequence. Bone edema was visualized using the 3D-STIR sequence and periapical hard tissue changes were evaluated using the 3D-T1 sequence.
Insights Imaging
January 2025
Institute of Diagnostic and Interventional Radiology, University Hospital Zurich (USZ), Zurich, Switzerland.
Objectives: To determine whether deep learning-based reconstructions of zero-echo-time (ZTE-DL) sequences enhance image quality and bone visualization in cervical spine MRI compared to traditional zero-echo-time (ZTE) techniques, and to assess the added value of ZTE-DL sequences alongside standard cervical spine MRI for comprehensive pathology evaluation.
Methods: In this retrospective study, 52 patients underwent cervical spine MRI using ZTE, ZTE-DL, and T2-weighted 3D sequences on a 1.5-Tesla scanner.
J Acoust Soc Am
January 2025
Key Laboratory of Modern Acoustics (MOE), School of Physics, Collaborative Innovation Centre of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
In thermal therapies, accurate estimation of in-tissue power deposition density (PDD) is essential for predicting temperature distributions over time or regularizing temperature imaging. Based on our previous work on ultrasound thermometry, namely, multi-thread thermal strain imaging (MT-TSI), this work develops an in vivo PDD estimation method. Specifically, by combining the TSI model infinitesimal echo strain filter with the bio-heat transfer theory (the Pennes equation), a finite-difference time-domain model is established to allow online extraction of the PDD.
View Article and Find Full Text PDFBackground: Heart Failure (HF) quality of care (QoC) is associated with clinical outcomes. Therefore, we investigated differences in HF QoC across worldwide regions (with differing national income) and the association of quality indicators with outcomes.
Methods: We examined the quality of care (QoC) in acute heart failure (HF) patients across different regions using quality indicators (QIs) from the European Society of Cardiology (ESC) and the American Heart Association (AHA) to evaluate QoC.
Adv Healthc Mater
January 2025
Department of Physical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Manauli, 140306, India.
Fluoropolymer alone, as an alternative to lead-based piezoelectric materials, has shown multiple challenges to develop useful sensors for solving real-world problems such as photoacoustic, ultrasound pulse echo, and other non-destructive testing. This work demonstrates the fabrication of high frequency and wide bandwidth transducers with fluoropolymer and highly polarizing cubic single crystal Barium titanate (BaTiO) ceramic composite for high resolution in-vivo photo-acoustic and ultrasound imaging. For transducer fabrication, a customized bio-compatible nanocomposite sensor film of PVDF-TrFE (Polyvinylidene fluoride trifluoroethylene)/BaTiO (BTO) is synthesized by drop and dry in heating-cum-electro-poling system for advancing polarization, crystallinity, and higher charge generation.
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