Medir o cérebro, para quê?

Authors

  • J. Cruz Maurício Professor Associado Convidado com Agregação. Faculdade de Ciências Médicas da Universidade Nova de Lisboa. Lisboa, Portugal.
  • Margarida Ribeiro Área Científica de Radiologia, Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa. Lisboa, Portugal. Centro de Física da Matéria Condensada, Universidade de Lisboa. Lisboa, Portugal. Departamento de Anatomia, Faculdade de Ciências Médicas, Universidade Nova de Lisboa. Lisboa, Portugal.
  • José Marçalo Técnico de Radiologia – Diamecon/Tomar. Tomar, Portugal.

DOI:

https://doi.org/10.25758/set.244

Keywords:

Magnetic resonance, Medical imagiology

Abstract

Várias são as “janelas” da Ressonância Magnética (RM) que hoje têm aplicação na clínica. Servem para fundamentar o diagnóstico (p.e., da encefalopatia microvascular do idoso), o prognóstico (p.e., do declínio cognitivo), a terapêutica (p.e., da desmielinização  primária). Com elas também poderemos aceder ao estudo fiável da substância branca aparentemente normal (T2 convencional), o que será importante para prever a evolução. Havendo, agora, uma outra contrastização quantificável – sem T1 nem T2 –, a designação genérica dos métodos será RMq. Duas são as nossas interrogações durante a execução e interpretação da RMq. A primeira, de índole executiva, questiona o enquadramento clínico destes estudos estruturais? De modo isolado ou partilhado? Opinamos que as duas “janelas” da RMq serão complementares e, por isso, de comum aplicação por rotina – transferência da
magnetização (TM) e difusão protónica (D/ADC). Por que as consideramos complementares entre si? Porque cada uma, a seu modo, ou seja, pela interacção da água ligada às macromoléculas, na TM, e pelo movimento molecular activo, na D/ADC, é propícia à medição da estrutura e da neurobiologia. Para ambas, o substrato será a célula com a membrana de mielina e a água, que lhe estará associada. Então, a RMq será uma sonda in vivo para a função.

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Published

2009-11-15

Issue

Section

Artigos de Revisão

How to Cite

Medir o cérebro, para quê?. (2009). Saúde & Tecnologia, 04, 05-15. https://doi.org/10.25758/set.244