Year: 2025
Type: article
Abstract: Background : Fluorine‐19 ( 19 F) magnetic resonance imaging (MRI) is a non‐invasive imaging tool for the targeted application of fluorinated agents, such as cell tracking, and for the demonstration of oximetry. However, as the SNR of 19 F is significantly weaker than that of proton ( 1 H) imaging, the 19 F coil must be combined with 1 H coils for anatomical co‐registration and B 0 shimming. This is difficult due to the strong coupling between the coils when they are in proximity, and is problematic since the Larmor frequency of 19 F is 94% that of 1 H, further increasing the potential for coupling between the 1 H and 19 F elements. Purpose : Conventional double‐tuned coil methods tend to generate loss compared to single‐tuned reference coils. The asymmetrical butterfly coil has a split resonance peak, which can cover frequencies of 1 H and 19 F without losses arising from lossy traps or switching circuits. In this study, the use of an asymmetrical butterfly coil was evaluated for 1 H/ 19 F applications. Methods : To increase quadrature efficiency at both the 1 H and 19 F frequencies, the left and right loops of the butterfly coil were tuned asymmetrically. The coil's tuning and performance were evaluated in simulations and MR measurements, and the results were compared to a dimension‐matched single‐tuned loop coil. Results : The split resonance peak of the asymmetrical butterfly coil successfully spanned the 19 F to 1 H frequency. It operated with higher quadrature efficiency at both 1 H and 19 F frequencies and demonstrated superior receive sensitivity and SNR compared to the dimension‐matched single‐tuned loop coil. Conclusions : The split resonance peak of the asymmetrical butterfly coil supported both 1 H and 19 F frequencies, delivering a higher SNR than that of the single‐tuned loop coil. Since the asymmetrical butterfly coil can cover ¹H and ¹⁹F frequencies without loss and provides higher efficiency than the reference single‐tuned coil, it can be effectively utilized for ¹H/¹⁹F MRI applications.
Source: Medical Physics
DOI: 10.1002/mp.17890
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $3,360
OpenAlex ID: W4410501040