To evaluate the safety and image quality of 1.5-T MRI in patients with cochlear implants retained internal magnets.Retrospective case series from 2012 to 2014.Single tertiary academic referral center.All implant recipients undergoing without magnet removal.MRI after tight headwrap application.Patient tolerance, complications, characteristics imaging artifact.Nineteen ears underwent a total 34 scans. Two did not tolerate place required removal before rescanning. One subject experienced two...

The purpose of this study is to provide a framework for the development quality assurance (QA) program use in medical 3D printing applications. An interdisciplinary QA team was built with expertise from all aspects printing. A systematic approach established assess accuracy and precision each step during process, including: image data acquisition, segmentation processing, cleaning. Validation printed models performed by qualitative inspection quantitative measurement. latter achieved...

The use of dedicated magnetic resonance simulation (MR-SIM) platforms in Radiation Oncology has expanded rapidly, introducing new equipment and functionality with the overall goal improving accuracy radiation treatment planning. However, this emerging technology presents a set challenges that need to be addressed for safe effective MR-SIM implementation. major objectives report are provide recommendations commercially available MR simulators, including initial selection, siting, acceptance...

MR elastography (MRE) is a noninvasive technique in which images of externally generated waves propagating tissue are used to measure stiffness. The first aim determine, from range driver configurations, the optimal for purpose generating within heart vivo. second quantify shear stiffness normal myocardium throughout cardiac cycle using MRE and compare left ventricular chamber pressure an vivo pig model. was performed six pigs with different setups, including no motion, three drivers, two...

<h3>BACKGROUND AND PURPOSE:</h3> Our aim was to noninvasively evaluate gliomas with MR elastography characterize the relationship of tumor stiffness grade and mutations in <i>isocitrate dehydrogenase 1</i> (<i>IDH1</i>) gene. <h3>MATERIALS METHODS:</h3> Tumor properties were prospectively quantified 18 patients (mean age, 42 years; 6 women) histologically proved using from 2014 2016. Images acquired on a 3T imaging unit vibration frequency 60 Hz. compared unaffected contralateral white...

Purpose To evaluate if cardiac magnetic resonance elastography (MRE) can measure increased stiffness in patients with amyloidosis. Myocardial tissue plays an important role function. A noninvasive quantitative imaging technique capable of measuring myocardial could aid disease diagnosis, therapy monitoring, and prognostic strategies. We recently developed a high‐frequency MRE making measurements. Materials Methods In all, 16 volunteers 22 amyloidosis were enrolled this study after...

Magnetic resonance (MR) imaging of the shoulder necessitates high spatial and contrast resolution resulting in long acquisition times, predisposing these images to degradation due motion. Autocorrection is a new motion correction algorithm that attempts deduce during by calculating metric reflects image quality searching for values optimize this metric. The purpose work report on evaluation 24 metrics use autocorrection MR rotator cuff. Raw data from 164 clinical coronal cuff exams acquired...

Abstract Magnetic resonance elastography (MRE) measurements of shear stiffness (μ) in a spherical phantom experiencing both static and cyclic pressure variations were compared to those derived from an established pressure–volume (P‐V)‐based model. A was constructed using silicone rubber composite 10 cm inner diameter 1.3 thickness. gradient echo MRE sequence used determine μ within the at pressures ranging 55 90 mmHg. Average values obtained region interest P‐V‐derived estimates. Under...

Abstract Purpose: To develop a novel MR‐based method for visualizing the elastic properties of human lung parenchyma in vivo and to evaluate ability this resolve differences parenchymal stiffness at different respiration states healthy volunteers. Materials Methods: A spin‐echo MR Elastography (MRE) pulse sequence was developed provide both high shear wave motion sensitivity short TE improved visualization parenchyma. The approach modeled tested with phantom experiments. In testing then...

Purpose To (a) evaluate modified spin-echo (SE) magnetic resonance (MR) elastographic sequences for acquiring MR images with improved signal-to-noise ratio (SNR) in patients whom the standard gradient-echo (GRE) sequence yields low hepatic signal intensity and (b) compare stiffness values obtained these those conventional GRE sequence. Materials Methods This HIPAA-compliant retrospective study was approved by institutional review board; requirement to obtain informed consent waived. Data SE...

: Tobacco-related pathologies are the most preventable diseases. The purpose is to provide personalized cartography of smoker lung stiffness using non-irradiating imaging modalities, MRI and MRE (magnetic resonance imaging/elastography). Thirty-four smokers were divided into five groups distributed with a range pack-years (PY) 10. All patients underwent three tests (CT: computed tomography, MRI, MRE) make possible measurements density, two modalities (CT, MR), stiffness. CT density was...

Magnetic resonance elastography (MRE) is a phase-contrast technique that can spatially map shear stiffness within tissue-like materials. To date, however, MRE of the lung has been too technically challenging-primarily because signal-to-noise ratio (SNR) limitations and phase instability. We describe an approach in which wave propagation not encoded into MR signal material, but rather from arising polarized noble gas encapsulated within. determine feasibility approach, three experiments were...

Purpose: The overall goal is to develop magnetic resonance elastography derived shear stiffness as a biomarker for the early identification of chemotherapy response, allowing dose, agent type and treatment regimen be tailored on per patient basis, improving therapeutic outcome minimizing normal tissue toxicity. specific purpose this study test feasibility novel measure response in well-known model. Methods: Tumors were grown right flank genetically modified mice by subcutaneous injection...

Purpose To investigate the influence of portal pressure on shear stiffness liver and spleen in a well‐controlled vivo porcine model with magnetic resonance elastography (MRE). A significant correlation between tissue could be used to noninvasively assess increased venous (portal hypertension), which is frequent clinical condition caused by cirrhosis responsible for development many lethal complications. Materials Methods During multiple intraarterial infusions Dextran‐40 three adult domestic...

The growth in the use of magnetic resonance imaging (MRI) data for radiation therapy (RT) treatment planning has been facilitated by scanner hardware and software advances that have enabled RT patients to be imaged position while providing morphologic functional assessment tumor volumes surrounding normal tissues. Despite these advances, manufacturers slow develop radiofrequency (RF) coils closely follow contour a patient undergoing MR imaging. Instead, relatively large form surface coil...

Magnetic resonance (MR) guided focused ultrasound (MRgFUS) is a hybrid technique which offers efficient and safe (FUS) treatments of uterine fibroids under MR guidance monitoring. As therapy device, MRgFUS requires systematic testing over wide range operational parameters prior to use in the clinical environment. We present technical acceptance tests data for first system, ExAblate® 2000 (InSightec Inc., Haifa, Israel), that has been FDA approved treating fibroids. These characterize by...

Abstract Purpose: To determine whether increasing epinephrine infusion in an vivo pig model is associated with increase end‐systolic magnetic resonance elastography (MRE)‐derived effective stiffness. Materials and Methods: Finite element modeling (FEM) was performed to the range of myocardial wall thicknesses that could be used for analysis. Then MRE on five pigs measure stiffness infusion. Epinephrine continuously infused intravenously each heart rate increments 20%. For such measured using...

Purpose To develop a rapid proton MR elastography (MRE) technique that can quantify the absolute shear stiffness of lung parenchyma, to investigate ability differentiate respiration‐dependent variations lung, and demonstrate clinical feasibility. Materials Methods A spin‐echo echo planar imaging MRE sequence (SE‐EPI MRE) with very short time was developed tested in series five healthy volunteers at three different volumes: (i) residual volume (RV), (ii) total capacity (TLC), (iii) midway...