Application of high‐density 2D receiver coil arrays for improved SNR in prostate MRI

• Published in: Magnetic resonance in medicine Vol. 93; no. 2; pp. 850 - 863
• Main Authors: Riederer, Stephen J., Borisch, Eric A., Du, Qingshuo, Froemming, Adam T., Hulshizer, Thomas C., Kawashima, Akira, McGee, Kiaran P., Robb, Fraser, Rossman, Phillip J., Takahashi, Naoki
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.02.2025
• Subjects: AIR coils; Arrays; Coils; Density; Diameters; Equipment Design; Humans; Image acquisition; Image Processing, Computer-Assisted - methods; Magnetic resonance imaging; Magnetic Resonance Imaging - instrumentation; Male; Middle Aged; MRI receiver coils; Phantoms, Imaging; Prostate; Prostate - diagnostic imaging; prostate cancer; Prostatic Neoplasms - diagnostic imaging; Reproducibility of Results; Signal-To-Noise Ratio; thin‐slice MRI; AIR coils; prostate cancer; MRI receiver coils; thin‐slice MRI
• ISSN: 0740-3194; 1522-2594; 1522-2594
• DOI: 10.1002/mrm.30289

Purpose To study if adaptive image receive (AIR) receiver coil elements can be configured into a 2D array with high (>45% by diameter) element‐to‐element overlap, allowing improved SNR at depth (0.7–1.5× element diameter) versus conventional (20%) overlap. Methods An anterior array composed of twenty 10‐cm diameter elements with 45% overlap arranged into a 4 × 5 grid and a similar 3 × 7 twenty‐one‐element posterior array were constructed. SNR and g‐factor were measured in a pelvic phantom using the new high‐density (HD) arrays (41 total elements) and compared to vendor AIR‐based arrays (30 total elements) with conventional overlap. T2‐weighted fast‐spin‐echo (T2SE) images acquired using both arrays were compared in 20 subjects. SNR was estimated in vivo. Results were compared blindly by three uroradiologists using a five‐point scale. Images using the HD arrays were also compared to a set of images acquired over a range of acceleration factors (R = 2.0, 2.5, 3.0) with the conventional arrays. Results SNR within the phantom was on average 15% higher for R = 1.0, 1.5, and 2.0 using the HD arrays. Across the 20 subjects SNR within the prostate was 11% higher and assessed radiologically as significantly higher (p < 0.001) for the HD versus conventional arrays. At all acceleration factors the new HD arrays outperformed the conventional arrays (p ≤ 0.01), allowing increased R for similar SNR. Conclusion AIR elements can be configured into 2D arrays with high (45%) element‐to‐element overlap, consistently providing increased SNR at depth versus arrays with conventional (20%) overlap. The SNR improvement allows increased acceleration in T2SE prostate MRI.