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3D Echo

Kyungsoo Bae, Kyung Nyeo Jeon, Moon Jung Hwang, Joon Sung Lee, Ji Young Ha, Kyeong Hwa Ryu, Ho Cheol Kim
OBJECTIVE: To determine the feasibility of using high-resolution volumetric zero echo time (ZTE) sequence in routine lung magnetic resonance imaging (MRI) and compare free breathing 3D ultrashort echo time (UTE) and ZTE lung MRI in terms of image quality and small-nodule detection. MATERIALS AND METHODS: Our Institutional Review Board approved this study. Twenty patients underwent both UTE and ZTE sequences during routine lung MR. UTE and ZTE images were compared in terms of subjective image quality and detection of lung parenchymal signal, intrapulmonary structures, and sub-centimeter nodules...
December 13, 2018: European Radiology
Edward Florez, Todd Nichols, Ellen E Parker, Seth T Lirette, Candace M Howard, Ali Fatemi
Purpose The definition of radiotherapy target volume is a critical step in treatment planning for all tumor sites. Conventional magnetic resonance imaging (MRI) pulse sequences are used for the definition of the gross target volume (GTV) and the contouring of glioblastoma multiforme (GBM) and meningioma. We propose the use of multiparametric MRI combined with radiomic features to improve the texture-based differentiation of tumor from edema for GTV definition and to differentiate vasogenic from tumor cell infiltration edema...
October 8, 2018: Curēus
Fabio Nery, Enrico De Vita, Chris A Clark, Isky Gordon, David L Thomas
PURPOSE: To develop a robust renal arterial spin labeling (ASL) acquisition and processing strategy for mapping renal blood flow (RBF) in a pediatric cohort with severe kidney disease. METHODS: A single-shot background-suppressed 3D gradient and spin-echo (GRASE) flow-sensitive alternating inversion recovery (FAIR) ASL acquisition method was used to perform 2 studies. First, an evaluation of the feasibility of single-shot 3D-GRASE and retrospective noise reduction methods was performed in healthy volunteers...
December 7, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Maya Delbany, Aurélien Bustin, Julie Poujol, Isabelle Thomassin-Naggara, Jacques Felblinger, Pierre-André Vuissoz, Freddy Odille
PURPOSE: To quantitatively evaluate a superresolution technique for 3D, one-millimeter isotropic diffusion-weighted imaging (DWI) of the whole breasts. METHODS: Isotropic 3D DWI datasets are obtained using a combination of (i) a readout-segmented diffusion-weighted-echo-planar imaging (DW-EPI) sequence (rs-EPI), providing high in-plane resolution, and (ii) a superresolution (SR) strategy, which consists of acquiring 3 datasets with thick slices (3 mm) and 1-mm shifts in the slice direction, and combining them into a 1 × 1 × 1-mm3 dataset using a dedicated reconstruction...
December 10, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Alexander Sedaghat, Baravan Al-Kassou, Vivian Vij, Dominik Nelles, Marko Stuhr, Robert Schueler, Heyder Omran, Jan Wilko Schrickel, Christoph Hammerstingl, Georg Nickenig
AIMS: Percutaneous left atrial appendage occlusion (LAAo) is commonly performed under fluoroscopy including the use of contrast dye. In this study, we aimed to assess feasibility and safety of contrast-free, 3D-echo-based LAAo with the use of the AMPLATZER™ Amulet™ device. METHODS AND RESULTS: We analyzed 20 patients (74 ± 10 years, 65% males) at an increased thromboembolic and bleeding risk (CHA2 DS2 VASC 4.0 ± 1.3; HAS-BLED 3.5 ± 0.9) with chronic renal failure (GFR 41 ± 21 ml/min) undergoing LAAo without the use of contrast dye at our center and compared the results with a propensity-matched cohort (1:1 matching) of conventionally treated patients receiving contrast agent...
December 10, 2018: Clinical Research in Cardiology: Official Journal of the German Cardiac Society
E Blondiaux, G Autret, F Dhombres, M Gonzales, E Audureau, O Clément, J-M Jouannic, L Houyel
PURPOSE: The purpose of this study was to compare non-invasive high-spatial-resolution postmortem cardiac magnetic resonance imaging (MRI) and autopsy findings for evaluating the septal insertion of atrioventricular valves in fetuses. MATERIALS AND METHODS: Five fetal heart specimens including two normal hearts, one heart with complete atrioventricular septal defect (AVSD) and two hearts with linear insertion of atrioventricular valves (LIAVV; gestational age 17 to 34 weeks) were studied with cardiac MRI using a 4...
December 7, 2018: Diagnostic and Interventional Imaging
Nian Wang, Gary Cofer, Robert J Anderson, Yi Qi, Chunlei Liu, G Allan Johnson
To evaluate the feasibility of compressed sensing (CS) for accelerating quantitative susceptibility mapping (QSM) acquisition in MR histology, control, demyelination, and remyelination mice were scanned using a modified 3D gradient echo pulse sequence (allowing undersampling the k-space in two phase dimensions) at 9.4 T. Fully sampled and compressed sensing data at various acceleration factors (4.0 ~ 16.0) were acquired with high spatial resolution of 22.5 μm3 isotropic. For prospective scans, the local phase was reconstructed slice-by-slice using a nonlinear reconstruction algorithm with phase cycling, and the QSM was calculated using the iLSQR method...
November 15, 2018: Physics in Medicine and Biology
Yinran Chen, Jing Liu, Julien Grondin, Elisa E Konofagou, Jianwen Luo
A high volume rate and high performance ultrasound imaging method based on a matrix array is proposed by using compressed sensing (CS) to reconstruct the complete dataset of synthetic transmit aperture (STA) from three-dimensional (3D) diverging wave transmissions (i.e., 3D CS-STA). Hereto, a series of apodized 3D diverging waves are transmitted from a fixed virtual source, with the i<sup>th</sup> row of a Hadamard matrix taken as the apodization coefficients in the i<sup>th</sup> transmit event...
December 4, 2018: Physics in Medicine and Biology
Sachi Okuchi, Yasutaka Fushimi, Tomohisa Okada, Akira Yamamoto, Tsutomu Okada, Takayuki Kikuchi, Kazumichi Yoshida, Susumu Miyamoto, Kaori Togashi
OBJECTIVES: To compare visualization of carotid plaques and vessel walls between 3D T1-fast spin echo imaging with conventional SPACE (T1-SPACE) and with a prototype compressed sensing T1-SPACE (CS-T1-SPACE) METHODS: This retrospective study was approved by the institutional review board. Participants comprised 43 patients (36 males, 7 females; mean age, 71 years) who underwent carotid MRI including T1-SPACE and CS-T1-SPACE. The quality of visualization for carotid plaques and vessel walls was evaluated using a 5-point scale, and signal intensity ratios (SRs) of the carotid plaques were measured and normalized to the adjacent sternomastoid muscle...
December 6, 2018: European Radiology
J E Vranic, N M Cross, Y Wang, D S Hippe, E de Weerdt, M Mossa-Basha
BACKGROUND AND PURPOSE: Compressed sensing-sensitivity encoding is a promising MR imaging acceleration technique. This study compares the image quality of compressed sensing-sensitivity encoding accelerated imaging with conventional MR imaging sequences. MATERIALS AND METHODS: Patients with known, treated, or suspected brain tumors underwent compressed sensing-sensitivity encoding accelerated 3D T1-echo-spoiled gradient echo or 3D T2-FLAIR sequences in addition to the corresponding conventional acquisition as part of their clinical brain MR imaging...
December 6, 2018: AJNR. American Journal of Neuroradiology
Jakob Meineke, Tim Nielsen
PURPOSE: Introduce a method to estimate <mml:math xmlns:mml=""> <mml:msub> <mml:mi>B</mml:mi> <mml:mn>0</mml:mn> </mml:msub> </mml:math> -fluctuations based on the analysis of raw k-space data, without sequence modifications or external hardware, and correct for their detrimental effects in gradient-echo MRI. THEORY: Inconsistencies in multi-channel raw k-space data can be used to estimate <mml:math xmlns:mml="http://www...
December 4, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Jisook Yi, Young Han Lee, Ho-Taek Song, Jin-Suck Suh
The objectives of this study were to compare the ultrashort T2* relaxation time with the T2* relaxation time using the 3 dimensional (3D) cones sequence in 3 groups of patients with normal, degenerated, and torn knee menisci, and to demonstrate the additional effect of the ultrashort echo time (UTE) signal intensity.Following institutional review board approval, 42 knee magnetic resonance imaging (MRI) scans of 42 patients who presented with knee pain and underwent knee MRIs, with the 3D Cones of UTE sequence (minimum TEs: 32 μs) and a 3T MRI scanner (Discovery 750, GE Healthcare, Waukesha, WI), were analyzed...
November 2018: Medicine (Baltimore)
Nassim Tayari, Jiri Obels, Thiele Kobus, Tom W J Scheenen, Arend Heerschap
PURPOSE: Quality control (QC) is a prerequisite for clinical MR spectroscopic imaging (MRSI) to avoid that bad spectra hamper data interpretation. The aim of this work was to present a simple automatic QC for prostate 1 H MRSI that can handle data obtained with different commonly used pulse sequences, echo times, field strengths, and MR platforms. METHODS: A QC method was developed with a ratio (Qratio) where the numerator and the denominator are functions of several signal heights, logically combined for their positive or negative contribution to spectral quality...
December 2, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Shinwan Kany, Ardan M Saguner
Usefulness of Electroanatomical Mapping in Rhythmology Abstract. Atrial fibrillation is the most common arrhythmia and its prevalence is rising. Therapeutic options include drug treatment and interventional catheter ablation via pulmonary vein isolation (PVI). This procedure was associated with long fluoroscopy times which carried risks for patients and physicians. Electroanatomical mapping (EAM) is a tool to visualize anatomy, voltage and activation of the heart chambers. Current EAM systems used in clinical practice include CARTO®, EnSite NavX® and Rhythmia®...
November 2018: Praxis
Markus Henningsson, Riad Abou Zahr, Adrian Dyer, Gerald F Greil, Barbara Burkhardt, Animesh Tandon, Tarique Hussain
BACKGROUND: Volumetric black-blood cardiovascular magnetic resonance (CMR) has been hampered by long scan times and flow sensitivity. The purpose of this study was to assess the feasibility of black-blood, electrocardiogram (ECG)-triggered and respiratory-navigated 3D fast spin echo (3D FSE) for the visualization of the whole heart and great vessels. METHODS: The implemented 3D FSE technique used slice-selective excitation and non-selective refocusing pulses with variable flip angles to achieve constant echo signal for tissue with T1 (880 ms) and T2 (40 ms) similar to the vessel wall...
November 26, 2018: Journal of Cardiovascular Magnetic Resonance
Daiki Ito, Tomokazu Numano, Koichi Takamoto, Takamichi Ueki, Tetsushi Habe, Keisuke Igarashi, Kazuyuki Mizuhara, Hisao Nishijo
We developed a Magnetic Resonance elastography (MRE) technique using a conventional magnetic resonance imaging (MRI), which allows a simultaneous elastography of the supraspinatus and trapezius muscles, by designing a new wave transducer (vibration pad) and optimizing the mechanical vibration frequency. Five healthy volunteers underwent an MRE. In order to transmit the mechanical vibration (pneumatic vibration) to the supraspinatus and trapezius muscles, a new vibration pad was designed using a three-dimensional (3D) printer...
November 19, 2018: Magnetic Resonance Imaging
Masato Kiriki, Wataru Jomoto, Takashi Ikeda, Noriko Kotoura
The purpose of this study was to evaluate the degree of signal attenuation generated around the stent by the susceptibility artifacts and radiofrequency (RF) shielding in phase contrast-magnetic resonance angiography (PCA) images and construct optimal PCA imaging parameters for intracranial stent lumen images. The two types of PCA images of stents (Neuroform, Enterpraise II) placed in the vascular flow phantom were imaged with different the flip angle (FA) and echo time (TE). Each original image of the vascular flow phantom was reconstructed into a coronal multiplanar reconstruction (MPR) image and a profile curve along the long axis of the stent was calculated...
2018: Nihon Hoshasen Gijutsu Gakkai Zasshi
F van den Noort, C H van der Vaart, A T M Grob, M K van de Waarsenburg, C H Slump, M van Stralen
OBJECTIVES: Measuring the length, width and area of the urogenital hiatus (UH), and the length and mean echo intensity (MEP) of the Puborectalis muscle (PRM) automatically and observer independently in the plane of minimal hiatal dimensions from transperineal ultrasound (TPUS) images by automatic segmentation of the UH and the PRM using deep learning. METHODS: In 1318 3D/4D TPUS volume datasets, images of the plane of minimal hiatal dimensions were manually obtained and the UH and the PRM were manually segmented...
November 21, 2018: Ultrasound in Obstetrics & Gynecology
Jiwon Kim, Javid Alakbarli, Brian Yum, Nathan H Tehrani, Meridith P Pollie, Christiane Abouzeid, Antonino Di Franco, Mark B Ratcliffe, Athena Poppas, Robert A Levine, Richard B Devereux, Jonathan W Weinsaft
Ischemic mitral regurgitation (iMR) augments risk for right ventricular dysfunction (RVDYS ). Right and left ventricular (LV) function are linked via common coronary perfusion, but data is lacking regarding impact of LV ischemia and infarct transmurality-as well as altered preload and afterload-on RV performance. In this prospective multimodality imaging study, stress CMR and 3-dimensional echo (3D-echo) were performed concomitantly in patients with iMR. CMR provided a reference for RVDYS (RVEF < 50%), as well as LV function/remodeling, ischemia and infarction...
November 20, 2018: International Journal of Cardiovascular Imaging
Delaram Shakoor, Richard Kijowski, Ali Guermazi, Jan Fritz, Frank W Roemer, Sahar Jalali-Farahani, John Eng, Shadpour Demehri
Purpose To investigate the diagnostic performance of three-dimensional (3D) MRI for depicting meniscal injuries of the knee by using surgery as the standard of reference. Materials and Methods A literature search was performed to identify original studies published between 1985 and 2017. Summary receiver operating characteristic curve and sensitivity analyses were performed to compare the diagnostic performance of 3D versus two-dimensional (2D) MRI for the assessment of knee meniscal injuries and to evaluate the impact of relevant covariates on the diagnostic performance for assessment of knee meniscal injuries...
November 20, 2018: Radiology
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