N.V. Anisimov1, A.A. Tarasova2, I.A. Usanov3, O.S. Pavlova4, D.A. Cheshkov5, Yu.A. Pirogov6

1,4 Faculty of Fundamental Medicine, Lomonosov Moscow State University (Moscow, Russian)

2,3,4,6 Faculty of Physics, Lomonosov Moscow State University (Moscow, Russian)

5 State Scientific Research Institute of Chemistry and Technology of Organoelement Compounds (Moscow, Russian)

The specificity of NMR signal detection in presence of the pulse interference and continuous wave (CW) interference with the frequency and amplitude that vary randomly over time is considered. For scanning with the signal accumulation, we suggest saving individual signal realizations. Those that are distorted by CW interference should be excluded from summing up, and those distorted by pulse interference should be edited. For scanning without phase cycling, we propose to scan without signal accumulation, but increasing the number of phase encoding steps necessary for high SNR and editing the pulse bursts in k-space. The activity of interference in different time intervals is analyzed on the data from 2D-NMR spectroscopy and MRI. This information was used in processing NMR spectra, in planning MRI experiments, and in assessing the information value of the acquired scans. The proposed approaches were implemented on a 0.5 T clinical scanner in 23Na MRI of human organs.

Anisimov N.V., Tarasova A.A., Usanov I.A., Pavlova O.S., Cheshkov D.A., Pirogov Yu.A. NMR signal detection in the presence of external interference. Electromagnetic waves and electronic systems. 2021. V. 26. № 5. P. 50−59. DOI: https://doi.org/10.18127/ j15604128-202105-06 (in Russian)

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