Sinais tomográficos precoces do AVC isquémico

Autores

  • Tiago Tribolet de Abreu Interno do Internato Complementar de Medicina Interna, Serviço de Medicina 2 do Hospital do Espírito Santo, Évora

Palavras-chave:

acidente vascular cerebral, tomografia axial computorizada

Resumo

A utilidade da Tomografia Axial Computorizada (TAC)
nas primeiras horas de um Acidente Vascular Cerebral
(AVC) isquémico tem sido reforçada. Não só se demonstrou
a sua capacidade para encontrar alterações nessas circunstâncias, como essas alterações poderão determinar ou não
a indicação para a terapêutica fibrinolítica. Desta forma, é
importante que todos os médicos envolvidos na abordagem
de doentes com AVC estejam familiarizados com os sinais
tomográficos precoces de um AVC isquémico.
As alterações da densidade dos tecidos cerebrais resultantes de isquemia são teoricamente visíveis em exames
tomográficos realizados nas primeiras 4 horas após o seu
início. Na prática, tal foi também verificado em estudos, quer animais, quer no homem.
O edema isquémico, sinal da artéria hiperdensa e edema
cerebral são as alterações potencialmente visíveis numa TAC
realizada nas primeiras horas após um AVC isquémico. Cada
um tem um significado e implicações próprias que, nalguns
casos, poderão chegar à contraindicação para fibrinólise.
Os autores apresentam exemplos de cada um dos sinais
precoces anteriormente referidos.

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Ficheiros Adicionais

Publicado

29-03-2002

Como Citar

1.
Tribolet de Abreu T. Sinais tomográficos precoces do AVC isquémico. RPMI [Internet]. 29 de Março de 2002 [citado 19 de Junho de 2024];9(1):45-51. Disponível em: https://revista.spmi.pt/index.php/rpmi/article/view/1850

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