TY - CHAP A1 - Gömmel, Andreas A1 - Niendorf, Thoralf A1 - Frauenrath, Tobias A1 - Otten, Mario A1 - Butenweg, Christoph A1 - Kob, Malte T1 - 3D vocal fold geometry mapping using Magnetic Resonance Imaging T2 - Fortschritte der Akustik : 36. Deutsche Jahrestagung für Akustik, Band 1 Y1 - 2010 SN - 978-3-9808659-8-2 N1 - Fortschritte der Akustik : 36. Deutsche Jahrestagung für Akustik ; 15.-18. März 2010, Berlin SP - 271 EP - 272 PB - Deutsche Gesellschaft für Akustik CY - Berlin ER - TY - CHAP A1 - Frauenrath, Tobias A1 - Gömmel, Andreas A1 - Butenweg, Christoph A1 - Otten, Mario A1 - Niendorf, Thoralf T1 - 3D mapping of vocal fold geometry during articulatory maneuvers using ultrashort echo time imaging at 3.0 T T2 - ISMRM-ESMRMB joint annual meeting 2010, Band 4 Y1 - 2010 SN - 978-1-617-82008-3 N1 - ISMRM-ESMRMB joint annual meeting 2010 : Stockholm, Sweden, 1 - 7 May 2010 SP - 3087 PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Gömmel, Andreas A1 - Frauenrath, Tobias A1 - Otten, Mario A1 - Niendorf, Thoralf A1 - Butenweg, Christoph ED - Möser, Michael ED - Schulte-Fortkamp, Brgitte ED - Ochmann, Martin T1 - In-vivo measurements of vocal fold geometry using Magnetic Resonance Imaging T2 - Fortschritte der Akustik - DAGA 2010, 36. Jahrestagung für Akustik Y1 - 2010 SN - 978-3-9808659-8-2 PB - Deutsche Gesellschaft für Akustik CY - Berlin ER - TY - JOUR A1 - Becker, Meike A1 - Frauenrath, Tobias A1 - Hezel, Fabian A1 - Krombach, Gabriele A. A1 - Kremer, Ute A1 - Koppers, Benedikt A1 - Butenweg, Christoph A1 - Goemmel, Andreas A1 - Utting, Jane F. A1 - Schulz-Menger, Jeanette A1 - Niendorf, Thoralf T1 - Comparison of left ventricular function assessment using phonocardiogram- and electrocardiogram-triggered 2D SSFP CINE MR imaging at 1.5 T and 3.0 T JF - European Radiology N2 - Objective: As high-field cardiac MRI (CMR) becomes more widespread the propensity of ECG to interference from electromagnetic fields (EMF) and to magneto-hydrodynamic (MHD) effects increases and with it the motivation for a CMR triggering alternative. This study explores the suitability of acoustic cardiac triggering (ACT) for left ventricular (LV) function assessment in healthy subjects (n=14). Methods: Quantitative analysis of 2D CINE steady-state free precession (SSFP) images was conducted to compare ACT’s performance with vector ECG (VCG). Endocardial border sharpness (EBS) was examined paralleled by quantitative LV function assessment. Results: Unlike VCG, ACT provided signal traces free of interference from EMF or MHD effects. In the case of correct Rwave recognition, VCG-triggered 2D CINE SSFP was immune to cardiac motion effects—even at 3.0 T. However, VCG-triggered 2D SSFP CINE imaging was prone to cardiac motion and EBS degradation if R-wave misregistration occurred. ACT-triggered acquisitions yielded LV parameters (end-diastolic volume (EDV), endsystolic volume (ESV), stroke volume (SV), ejection fraction (EF) and left ventricular mass (LVM)) comparable with those derived fromVCG-triggered acquisitions (1.5 T: ESVVCG=(56± 17) ml, EDVVCG=(151±32)ml, LVMVCG=(97±27) g, SVVCG=(94± 19)ml, EFVCG=(63±5)% cf. ESVACT= (56±18) ml, EDVACT=(147±36) ml, LVMACT=(102±29) g, SVACT=(91± 22) ml, EFACT=(62±6)%; 3.0 T: ESVVCG=(55±21) ml, EDVVCG=(151±32) ml, LVMVCG=(101±27) g, SVVCG=(96±15) ml, EFVCG=(65±7)% cf. ESVACT=(54±20) ml, EDVACT=(146±35) ml, LVMACT= (101±30) g, SVACT=(92±17) ml, EFACT=(64±6)%). Conclusions: ACT’s intrinsic insensitivity to interference from electromagnetic fields renders KW - Magnetic resonance imaging (MRI) KW - MR-stethoscope KW - Magnetic field strength KW - Left ventriular function KW - Cardiovascular MRI Y1 - 2010 U6 - https://doi.org/10.1007/s00330-009-1676-z SN - 1432-1084 (Onlineausgabe) SN - 0938-7994 (Druckausgabe) VL - 20 SP - 1344 EP - 1355 PB - Springer CY - Berlin ER - TY - JOUR A1 - Frauenrath, Tobias A1 - Hezel, Fabian A1 - Heinrichs, Uwe A1 - Kozerke, Sebastian A1 - Utting, Jane A1 - Kob, Malte A1 - Butenweg, Christoph A1 - Boesiger, Peter A1 - Niendorf, Thoralf T1 - Feasibility of Cardiac Gating Free of Interference With Electro-Magnetic Fields at 1.5 Tesla, 3.0 Tesla and 7.0 Tesla Using an MR-Stethoscope JF - Investigative Radiology KW - phonocardiogram KW - electrocardiogram KW - cardiac gating KW - high field MR imaging KW - cardiovascular MR imaging Y1 - 2009 U6 - https://doi.org/10.1097/RLI.0b013e3181b4c15e SN - 1536-0210 (online) SN - 0020-9996 (gedruckt) VL - 44 IS - 9 SP - 539 EP - 547 PB - Lippincott Williams & Wilkins ; (via Ovid) CY - Philadelphia, Pa ER - TY - GEN A1 - Frauenrath, Tobias A1 - Dieringer, Matthias A1 - Patel, Nishant A1 - Zerdem, Celal A1 - Hentschel, Jan A1 - Renz, Wolfgang A1 - Niendorf, Thoralf T1 - From Artifact to Merit: Cardiac Gated MRI at 7T & 3T using Magneto-Hydrodynamic Effects for Synchronization T2 - 2011 ISMRM Annual Meeting Proceedings N2 - ECG is corrupted by magneto-hydrodynamic effects at higher magnetic field strength. Artifacts in the ECG trace and severe T-wave elevation might be mis-interpreted as R-waves. MHD being inherently sensitive to blood flow and blood velocity provides an alternative approach for cardiac gating, even in peripheral target areas far away from the commonly used upper torso positions of ECG electrodes. This feature would be very beneficial to address traveling time induced motion artifacts and trigger latency related issues raised by ECG-gated peripheral MR angiography. For all those reasons, this work proposes the use of MHD-trigger for cardiac gated MR. Y1 - 2011 SN - 1545-4428 N1 - ISMRM 19th Annual Meeting & Exhibition, 7-13 May 2011, Montreal, Quebec, Canada ER - TY - GEN A1 - Frauenrath, Tobias A1 - de Geyer d'Orth, Thibaut A1 - Niendorf, Thoralf T1 - Assessment of Accuracy & Reproducibility of ECG, Pulse Oximetry & Phonocardiogram Gating of Cardiac MRI at 7T T2 - 2011 ISMRM Annual Meeting Proceedings N2 - At (ultra)high magnetic fields the artifact sensitivity of ECG recordings increases. This bears the risk of R-wave mis-registration which has been consistently reported for ECG triggered CMR at 7.0T. Realizing the constraints of conventional ECG, acoustic cardiac triggering (ACT) has been proposed. The clinical ACT has not been carefully examined yet. For this reason, this work scrutinizes the suitability, accuracy and reproducibility of ACT for CMR at 7.0T. For this purpose, the trigger reliability and trigger detection variance are examined together with an qualitative and quantitative assessment of image quality of the heart at 7.0T. Y1 - 2011 SN - 1545-4428 N1 - ISMRM 19th Annual Meeting & Exhibition, 7-13 May 2011, Montreal, Quebec, Canada ER - TY - GEN A1 - Martin, Conrad Steven A1 - Frauenrath, Tobias A1 - Zerdem, Celal A1 - Renz, Wolfgang A1 - Niendorf, Thoralf T1 - Evaluation of Magneto Alert Sensor (MALSE) to Improve MR Safety by Decreasing the Incidence of Ferromagnetic Projectile Accidents T2 - 2011 ISMRM Annual Meeting Proceedings N2 - The magnetic forces of fringe magnetic fields of MR systems on ferromagnetic components can impose a severe patient, occupational health and safety hazard. MRI accidents are listed as number 9 of the top 10 risks in modern medicine. With the advent of ultrahigh field MR systems including passively shielded magnet versions, this risk, commonly known as the missile or projectile effect is even more pronounced. A strategy employing magnetic field sensors which can be attached to ferromagnetic objects that are commonly used in a clinical environment is conceptually appealing for the pursuit of reducing the risk of ferromagnetic projectile accidents. Y1 - 2011 SN - 1545-4428 N1 - ISMRM 19th Annual Meeting & Exhibition, 7-13 May 2011, Montreal, Quebec, Canada ER - TY - GEN A1 - Frauenrath, Tobias A1 - Renz, Wolfgang A1 - Rieger, Jan A1 - Gömmel, Andreas A1 - Butenweg, Christoph A1 - Niendorf, Thoralf T1 - High Spatial Resolution 3D MRI of the Larynx Using a Dedicated TX/RX Phased Array Coil at 7.0T T2 - 2010 ISMRM-ESMRMB joint annual meeting N2 - MRI holds great potential for elucidating laryngeal and vocal fold anatomy together with the assessment of physiological processes associated in human phonation. However, MRI of human phonation remains very challenging due to the small size of the targeted structures, interfering signal from fat, air between the vocal folds and surrounding muscles and physiological motion. These anatomical/physiological constraints translate into stringent technical requirements in balancing, scan time, image contrast, immunity to physiological motion, temporal resolution and spatial resolution. Motivated by these challenges and limitations this study is aiming at translating the sensitivity gain at ultra-high magnetic fields for enhanced high spatial resolution 3D imaging of the larynx and vocal tract. To approach this goal a dedicated two channel TX/RX larynx coil is being proposed. Y1 - 2010 SN - 1545-4428 N1 - ISMRM-ESMRMB joint annual meeting, 1 - 7 May 2010, Stockholm, Sweden ER - TY - GEN A1 - Hezel, Fabian A1 - Frauenrath, Tobias A1 - Renz, Wolfgang A1 - Schulz-Menger, Jeanette A1 - Niendorf, Thoralf T1 - Feasibility of CINE Myocardial T2* Mapping Using Susceptibility Weighted Gradient-Echo Imaging at 7.0 T T2 - 2010 ISMRM-ESMRMB joint annual meeting N2 - This study is designed to demonstrate the promise of susceptibility weighted 2D CINE FLASH and T2* Mapping of the heart at 7T. Y1 - 2010 SN - 1545-4428 N1 - ISMRM-ESMRMB joint annual meeting, 1 - 7 May 2010, Stockholm, Sweden ER -