The Role of Neurophysiological Monitoring during Complex Aneurysm Surgery: Report of Two Cases and Review of the Literature

Abstract

The surgical treatment of intracranial aneurysms is a routine operation in the neurosurgeon practice. Complex aneurysms are those with morphological irregularities, usually large or giant; thrombosed, partially thrombosed or calcified; with aberrant fundus/neck ratio and near eloquent neurological structures. These cases demand special skills by the surgical team. The present article is a report of two cases of complex aneurysms successfully treated, with a discussion on the role of neurophysiological monitoring. In these two cases of supra- and infratentorial complex giant aneurysms, intraoperative monitoring was extremely relevant. Thus, we believe that treating complex and giant aneurysms carries several pitfalls, and the use of multimodal intraoperative monitoring is mandatory to mitigate risks and deliver the best result to the patient.

Resumo

O tratamento cirúrgico de aneurismas intracranianos é uma cirurgia de rotina na prática neurocirúrgica. Aneurismas complexos são caracterizados por terem irregularidades morfológicas; serem grandes ou gigantes; parcialmente trombosados ou calcificados; com uma razão fundo/colo desfavorável ou aqueles próximos a estruturas neurológicas eloquentes.

Esses casos demandam habilidades específicas do time cirúrgico. Este estudo relata dois casos de tratamento bem sucedido de aneurismas complexos, discutindo o uso da monitorização neurofisológica intraoperatória. Em ambos casos, sendo um supratentorial e outro infratentorial, o uso de monitorização neurofisiológica intraoperatória foi essencial para avaliar a qualidade da clipagem dos aneurismas e eventualmente reposicionamento dos clipes para evitar déficits neurológicos.

Dessa forma, devido ao alto risco potencial de tratamento cirúrgico de aneurismas complexos, acreditamos que a monitorização intraoperatória neurofisiológica multimodal se faz mandatória para mitigar os riscos e alcançar o melhor resultado cirúrgico e funcional.

Keywords

intracranial aneurysm - surgery - neurophysiological monitoring - intraoperative angiography

Palavras-chave

aneurisma intracraniano - cirurgia - monitorização neurofisiológica - angiografia intraoperatória

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