Multi-center benchmarking of cervical spinal cord RF coils for 7 T MRI: A traveling spines study

Alonso-Ortiz, E.; Papp, D.; Barry, R. L.; Poeti, K.; Seifert, A. C.; Gilbert, K. M.; Rios, N. M. L.; Paska, J.; Eippert, F.; Weiskopf, N.; Beghini, L.; Graedel, N.; Trampel, R.; Callaghan, M. F.; Aigner, C.; Freund, P.; Seif, M.; Destruel, A.; Callot, V.; Vannesjo, J.; Cohen-Adad, J.

doi:10.1101/2025.01.13.632825

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bioRxiv · 10.1101/2025.01.13.632825

Multi-center benchmarking of cervical spinal cord RF coils for 7 T MRI: A traveling spines study

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Abstract

PurposeThe depth within the body, small diameter, long length, and varying tissue surrounding the spinal cord impose specific considerations when designing radiofrequency coils. The optimal coil configuration for 7 T cervical spinal cord MRI is unknown and, currently, there are very few coil options. The purpose of this work was (1) to establish a quality control protocol for evaluating 7 T cervical spinal cord coils and (2) to use that protocol to evaluate the performance of 4 different coil designs. MethodsThree healthy volunteers and a custom anthropomorphic phantom (the traveling spines cohort) were scanned at seven 7 T imaging centers using a common protocol and each centers specific cervical spinal cord coil. Four different coil designs were tested (two in-house, one Rapid Biomedical, and one MRI.TOOLS design). ResultsThe Rapid Biomedical coil was found to have the highest B1+ efficiency, whereas one of the in-house designs (NeuroPoly Lab) had the highest SNR and the largest spinal cord coverage. The MRI.TOOLS coil had the most uniform B1+ profile along the cervical spinal cord; however, it was limited in its ability to provide the requested flip angles (especially for larger individuals). The latter was also the case for the second in-house coil (MSSM). ConclusionThe results of this study serve as a guide for the spinal cord MRI community in selecting the most suitable coil based on specific requirements and offer a standardized protocol for assessing future coils.

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Alonso-Ortiz, E., Papp, D., Barry, R. L., Poeti, K., Seifert, A. C., Gilbert, K. M., Rios, N. M. L., Paska, J., Eippert, F., Weiskopf, N., Beghini, L., Graedel, N., Trampel, R., Callaghan, M. F., Aigner, C., Freund, P., Seif, M., Destruel, A., Callot, V., Vannesjo, J., Cohen-Adad, J.. 2025-01-17. Multi-center benchmarking of cervical spinal cord RF coils for 7 T MRI: A traveling spines study. https://doi.org/10.1101/2025.01.13.632825

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