TY  - JOUR
AU  - Faust, Jonas Frederik
AU  - Speier, Peter
AU  - Krafft, Axel Joachim
AU  - Patil, Sunil
AU  - Seethamraju, Ravi Teja
AU  - Ladd, Mark
AU  - Maier, Florian
TI  - Positive susceptibility-based contrast imaging with dephased balanced steady-state free precession.
JO  - Magnetic resonance in medicine
VL  - 94
IS  - 1
SN  - 1522-2594
CY  - New York, NY [u.a.]
PB  - Wiley-Liss
M1  - DKFZ-2025-00537
SP  - 59-72
PY  - 2025
N1  - Volume 94, Issue 1, July 2025 , Pages 59-72
AB  - Dephasing gradients can be introduced within a variety of gradient-echo pulse sequences to delineate local susceptibility changes ('White-Marker' phenomenon), e.g., for the visualization of metallic interventional devices which are otherwise difficult to display. We investigated dephased balanced steady-state free precession (d-bSSFP) and compared it with similar contrast techniques: dephased RF-spoiled fast low-angle shot (d-FLASH) and dephased steady-state free precession (d-SSFP).A signal model was formulated to describe the positive contrast in d-bSSFP. For the example of an MR-compatible aspiration needle, the positive contrast artifact appearance was theoretically derived, and the model was verified in a water phantom at B0 = 0.55 T. Model accuracy was evaluated by comparing the measured artifact size (for TEs between 3.4 ms and 50 ms) and the signal magnitude to the model prediction.While positive contrast artifacts for d-FLASH and d-SSFP are axisymmetric with respect to the generating object, for d-bSSFP, a point-symmetric susceptibility artifact arises for a cylindrical needle due to the characteristic signal formation. The observed d-bSSFP artifact size was in accordance with the model (error < 1 mm). Measured (predicted) cumulated artifact signal was 1.13 ± 0.07 (1.27) times higher and 5.9 ± 0.4 times higher than the d-SSFP and d-FLASH cumulated artifact signal, respectively. In contrast to d-SSFP, the d-bSSFP artifact was robust against banding artifacts.d-bSSFP contrast is well described by the introduced model. Positive contrast artifacts show higher cumulated signal magnitude, symmetry, and homogeneity compared with d-FLASH and d-SSFP and can therefore improve device visualization and potentially device localization.
KW  - bSSFP (Other)
KW  - dephased MRI (Other)
KW  - interventional MRI (Other)
KW  - positive contrast (Other)
KW  - white‐marker imaging (Other)
LB  - PUB:(DE-HGF)16
C6  - pmid:40079240
DO  - DOI:10.1002/mrm.30421
UR  - https://inrepo02.dkfz.de/record/299782
ER  -