An integrated RF-receive/B0-shim array coil boosts performance of whole-brain MR spectroscopic imaging at 7 T

• Published in: Scientific reports Vol. 10; no. 1; p. 15029
• Main Authors: Esmaeili, Morteza, Stockmann, Jason, Strasser, Bernhard, Arango, Nicolas, Thapa, Bijaya, Wang, Zhe, van der Kouwe, Andre, Dietrich, Jorg, Cahill, Daniel P., Batchelor, Tracy T., White, Jacob, Adalsteinsson, Elfar, Wald, Lawrence, Andronesi, Ovidiu C.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14.09.2020; Nature Publishing Group
• Subjects: 631/45/882; 639/166/985; 639/766/930/2735; 692/4028/67/2321; 692/4028/67/2327; Alveolar bone; Bacterial infections; Bone loss; Brain cancer; Brain tumors; Colonization; Gastrointestinal diseases; Glioma; Humanities and Social Sciences; Immune system; Immunoregulation; Innate immunity; Interleukin 6; Intestine; Lactobacillus gasseri; Metabolites; Monocytes; mRNA; Mucosa; multidisciplinary; Oral administration; Periodontal ligament; Periodontitis; Porphyromonas gingivalis; Probiotics; Science; Science (multidisciplinary); Tumor necrosis factor-α
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-71623-5

Metabolic imaging of the human brain by in-vivo magnetic resonance spectroscopic imaging (MRSI) can non-invasively probe neurochemistry in healthy and disease conditions. MRSI at ultra-high field (≥ 7 T) provides increased sensitivity for fast high-resolution metabolic imaging, but comes with technical challenges due to non-uniform B 0 field. Here, we show that an integrated RF-receive/B 0 -shim (AC/DC) array coil can be used to mitigate 7 T B 0 inhomogeneity, which improves spectral quality and metabolite quantification over a whole-brain slab. Our results from simulations, phantoms, healthy and brain tumor human subjects indicate improvements of global B 0 homogeneity by 55%, narrower spectral linewidth by 29%, higher signal-to-noise ratio by 31%, more precise metabolite quantification by 22%, and an increase by 21% of the brain volume that can be reliably analyzed. AC/DC shimming provide the highest correlation (R 2  = 0.98, P = 0.001) with ground-truth values for metabolite concentration. Clinical translation of AC/DC and MRSI is demonstrated in a patient with mutant-IDH1 glioma where it enables imaging of D-2-hydroxyglutarate oncometabolite with a 2.8-fold increase in contrast-to-noise ratio at higher resolution and more brain coverage compared to previous 7 T studies. Hence, AC/DC technology may help ultra-high field MRSI become more feasible to take advantage of higher signal/contrast-to-noise in clinical applications.