Magnetoencephalography in clinical practice

ABSTRACT

Magnetoencephalography (MEG) is a neurophysiological technique that measures the magnetic fields associated with neuronal activity in the brain. It is closely related but distinct from its counterpart electroencephalography (EEG). The first MEG was recorded more than 50 years ago and has technologically evolved over this time. It is now well established in clinical practice particularly in the field of epilepsy surgery and functional brain mapping. However, underutilization and misunderstanding of the clinical applications of MEG is a challenge to more widespread use of this technology. A fundamental understanding of the neurophysiology and physics of MEG is discussed in this article as well as practical issues related to implementation, analysis, and clinical applications. The future of MEG and some potential clinical applications are briefly reviewed.

RESUMO

A magnetoencefalografia (MEG) é uma técnica neurofisiológica que mede os campos magnéticos associados à atividade neuronal no cérebro. A técnica é distinta da eletroencefalografia (EEG), porém está intimamente relacionada a ela. A primeira foi registrada há mais de 50 anos e evoluiu tecnologicamente ao longo do tempo. Está agora bem estabelecida na prática clínica, particularmente nos campos da cirurgia de epilepsia e mapeamento cerebral funcional. No entanto, a subutilização e a incompreensão das aplicações clínicas da MEG são um desafio para o uso mais amplo dessa tecnologia. Suas bases neurofisiológica e física são discutidas neste artigo, bem como questões práticas relacionadas à sua implementação, análise e aplicações clínicas. O futuro da MEG e algumas aplicações clínicas potenciais são brevemente revistos.

Keywords:

Magnetoencephalography - Electroencephalography - Neurophysiology - Magnetic Resonance Imaging - Brain Mapping

Palavras-chave:

Magnetoencefalografia - Eletroencefalografia - Neurofisiologia - Imagem por Ressonância Magnética - Mapeamento Encefálico

Authors’ contributions:

MH: conceptualization, writing of original draft (lead); JG: conceptualization, manuscript review and editing (lead).

Publication History

Received: 02 March 2021

Accepted: 14 August 2021

Article published online:
06 February 2023

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