TY  - JOUR
A1  - Frauenrath, Tobias
A1  - Niendorf, Thoralf
A1  - Kob, Malte
T1  - Acoustic method for synchronization of Magnetic Resonance Imaging (MRI)
JF  - Acta Acustica
N2  - Magnetic Resonance Imaging (MRI) of moving organs requires synchronization with physiological motion or flow, which dictate the viable window for data acquisition. To meet this challenge, this study proposes an acoustic gating device (ACG) that employs acquisition and processing of acoustic signals for synchronization while providing MRI compatibility, immunity to interferences with electro-magnetic and acoustic fields and suitability for MRI at high magnetic field strengths. The applicability and robustness of the acoustic gating approach is examined in a pilot study, where it substitutes conventional ECG-gating for cardiovascular MR. The merits and limitations of the ACG approach are discussed. Implications for MR imaging in the presence of physiological motion are considered including synchronization with other structure- or motion borne sounds.
Y1  - 2008
U6  - https://doi.org/10.3813/AAA.918017
SN  - 1861-9959
VL  - 94
IS  - 1
SP  - 148
EP  - 155
PB  - Hirzel
CY  - Stuttgart
ER  - 
TY  - JOUR
A1  - von Knobelsdorf-Brenkenhoff, Florian
A1  - Frauenrath, Tobias
A1  - Prothmann, Marcel
A1  - Dieringer, Matthias A.
A1  - Hezel, Fabian
A1  - Renz, Wolfgang
A1  - Kretschel, Kerstin
A1  - Niendorf, Thoralf
A1  - Schulz-Menger, Jeanette
T1  - Cardiac chamber quantification using magnetic resonance imaging at 7 Tesla—a pilot study
N2  - Objectives
Interest in cardiovascular magnetic resonance (CMR) at 7 T is motivated by the expected increase in spatial and temporal resolution, but the method is technically challenging. We examined the feasibility of cardiac chamber quantification at 7 T.

Methods
A stack of short axes covering the left ventricle was obtained in nine healthy male volunteers. At 1.5 T, steady-state free precession (SSFP) and fast gradient echo (FGRE) cine imaging with 7 mm slice thickness (STH) were used. At 7 T, FGRE with 7 mm and 4 mm STH were applied. End-diastolic volume, end-systolic volume, ejection fraction and mass were calculated.

Results
All 7 T examinations provided excellent blood/myocardium contrast for all slice directions. No significant difference was found regarding ejection fraction and cardiac volumes between SSFP at 1.5 T and FGRE at 7 T, while volumes obtained from FGRE at 1.5 T were underestimated. Cardiac mass derived from FGRE at 1.5 and 7 T was larger than obtained from SSFP at 1.5 T. Agreement of volumes and mass between SSFP at 1.5 T and FGRE improved for FGRE at 7 T when combined with an STH reduction to 4 mm.

Conclusions
This pilot study demonstrates that cardiac chamber quantification at 7 T using FGRE is feasible and agrees closely with SSFP at 1.5 T.
Y1  - 2010
U6  - https://doi.org/10.1007/s00330-010-1888-2
SN  - 0938-7994
VL  - 20
SP  - 2844
EP  - 2852
PB  - Springer
CY  - Berlin, Heidelberg
ER  - 
TY  - JOUR
A1  - Droop, Philipp
A1  - Chen, Shaohuang
A1  - Radford, Melissa J.
A1  - Paulßen, Elisabeth
A1  - Gates, Byron D.
A1  - Reilly, Raymond M.
A1  - Radchenko, Valery
A1  - Hoehr, Cornelia
T1  - Synthesis of 197m/gHg labelled gold nanoparticles for targeted radionuclide therapy
JF  - Radiochimica Acta
N2  - Meitner-Auger-electron emitters have a promising potential for targeted radionuclide therapy of cancer because of their short range and the high linear energy transfer of Meitner-Auger-electrons (MAE). One promising MAE candidate is 197m/gHg with its half-life of 23.8 h and 64.1 h, respectively, and high MAE yield. Gold nanoparticles (AuNPs) that are labelled with 197m/gHg could be a helpful tool for radiation treatment of glioblastoma multiforme when infused into the surgical cavity after resection to prevent recurrence. To produce such AuNPs, 197m/gHg was embedded into pristine AuNPs. Two different syntheses were tested starting from irradiated gold containing trace amounts of 197m/gHg. When sodium citrate was used as reducing agent, no 197m/gHg labelled AuNPs were formed, but with tannic acid, 197m/gHg labeled AuNPs were produced. The method was optimized by neutralizing the pH (pH = 7) of the Au/197m/gHg solution, which led to labelled AuNPs with a size of 12.3 ± 2.0 nm as measured by transmission electron microscopy. The labelled AuNPs had a concentration of 50 μg (gold)/mL with an activity of 151 ± 93 kBq/mL (197gHg, time corrected to the end of bombardment).
KW  - 197m/gHg
KW  - Gold nanoparticle (AuNP)
KW  - Meitner-Auger-electron (MAE)
KW  - Targeted radionuclide therapy (TRT)
Y1  - 2023
U6  - https://doi.org/10.1515/ract-2023-0144
SN  - 2193-3405
VL  - 111
IS  - 10
SP  - 773
EP  - 779
PB  - De Gruyter
CY  - Berlin [u.a.]
ER  -