eprintid: 36541
rev_number: 13
eprint_status: archive
userid: 9006
dir: disk0/00/03/65/41
datestamp: 2025-05-15 12:44:27
lastmod: 2025-05-26 16:12:04
status_changed: 2025-05-15 12:44:27
type: doctoralThesis
metadata_visibility: show
creators_name: Grimm, Johannes Anton
title: Investigation of a remote 32-channel whole-body coil for large field of view 1H body imaging at 7 T
divisions: i-130001
divisions: i-850300
adv_faculty: af-13
abstract: This work aimed to evaluate the remote coil in comparison to existing local coils and to experimentally investigate the parallel transmit (pTx) capabilities of the remote coil through in-vivo measurements. The thesis was divided into two parts.
First, the transmit and receive performance of seven different local pTx coils and the remote coil (also in combination with a dedicated local receive array) were quantitatively assessed through phantom measurements. The remote coil demonstrated the largest excitation coverage in head-foot direction. Although, its maximum B1+ efficiency at the isocenter was 2.0 times lower than that of local transmit-receive coils, this limitation could be compensated with the four- or eight-fold higher total available power. While the best performing local transmit-receive coil enabled higher acceleration factors than the dedicated local receive array, the latter achieved the highest signal-to-noise ratio in the phantom’s center.
Second, the pTx capabilities of the remote coil were investigated through in-vivo measurements. The first study demonstrated homogeneous liver excitation using static pTx.
The second in-vivo study extended the excitation region to the whole abdomen, where two kT-point pTx pulses were required for sufficient homogeneity across all subjects.
In conclusion, the remote coil, combined with a dedicated local receive array, represents the state-of-the-art for body imaging at 7 T. These findings highlight its potential for large field-of-excitation imaging and its necessity for translating UHF body MRI into clinical practice.
date: 2025
id_scheme: DOI
id_number: 10.11588/heidok.00036541
ppn_swb: 1926646487
own_urn: urn:nbn:de:bsz:16-heidok-365417
date_accepted: 2025-04-30
advisor: HASH(0x55e83b028ff0)
language: eng
bibsort: GRIMMJOHANINVESTIGAT2025
full_text_status: public
place_of_pub: Heidelberg
citation:   Grimm, Johannes Anton  (2025) Investigation of a remote 32-channel whole-body coil for large field of view 1H body imaging at 7 T.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/36541/1/Dissertation_Johannes_Grimm.pdf