Dual Microscope Indocyanine Green Video Angiography and Endoscopic Review to Treat Intracranial Aneurysm: A Review of the Literature Regarding a Case.

The use of the indocyanine green video angiography (ICG-VA) both endoscope and microscope has become popular in recent decades thanks to the safety, efficacy, and added value that they have provided for cerebrovascular surgery. The dual use of these technologies is considered complementary and has helped cerebrovascular surgeons in decision-making, especially for aneurysm clipping surgery; however, its use has been described for both aneurysm surgery, resection of arteriovenous malformations, or even for bypass surgeries. We conducted a review of the literature with the MeSH terms "microscope indocyanine green video angiography (mICG-VA)," "endoscopic review," AND/OR "intracranial aneurysm." A total of 97 articles that included these terms were selected after a primary review to select a total of 26 articles for the final review. We also present a case to exemplify its use, in which we use both technological tools for the description of the aneurysm, as well as for decision-making at the time of clipping and for reclipping. Both tools, both the use of the endoscope and the mICG-VA, have helped decision-making in neurovascular surgery. A considerable clip replacement rate has been described with the use of these technologies, which has helped to reduce the complications associated with poor clipping. One of the main advantages of their usefulness is that they are tools for intraoperative use, which is why they have shown superiority compared to digital subtraction angiography, which takes longer to use and has a higher risk of complications associated with the contrast medium. On the other hand, a very low rate of complications has been described with the use of the endoscope and mICG-VA, which is why they are considered safe tools to use. In some cases, mention has been made of the use of one or the other technology; however, we consider that its dual use provides more information about the status of the clip, its anatomy, its relationship with other vascular structures, and the complete occlusion of the aneurysm. We consider that the use of both technologies is complementary, so in case of having them both should be used, since both the endoscope and the mICG-VA provide additional and useful information.

Neuroendoscope in aneurysm surgeries: past, present and future / Neuroendoscopia em cirurgia de aneurismas: passado, presente e futuro

Even with the use of most sophisticated microscope sometimes the relationship between the aneurysm and the adjacent structures are not clearly defined. The straight line of view by microscope results in inadequate visualization of structures thatlie immediately behind other structures like the neck, branches or perforators of the aneurysm. Hence exposure of these structures may require risky retraction either of the parent artery or the aneurysm itself, which can be overcome by clear anatomical information obtained by the use of endoscope instead of attempting extensive manipulation under the microscope. The endoscope permits close up, wide angled views of regional anatomic features and verification of the optimal clip position. Visual conformation of regional anatomy achieved using the rigid endoscope provides valuable information for subsequent microsurgical procedures and enhances the safety and reliability. Endoscopic-assisted microsurgery is an exceptional aid and using the PIP (picture-in picture) technology, simultaneous observation of microscope and endoscopic images can be viewed through the ocular system of microscope. The advantages of neuroendoscope include the ability to look around corners and behind obstructions. With less brain retraction, smaller operative exposures and better visualization, neuroendoscopy may reduce operative morbidity. However he surgeon should be familiar with this technique and be prepared for the inconveniences and risks during the procedure.

A neuroendoscopia reflete a tendência da neurocirurgia moderna em buscar acessos mínimos., ou seja, acessar e visualizar lesões através de corredores o menor possível e com máxima efetividade ao objetivo, com mínima alteração do tecido norma;. Embora o primeiro procedimento endoscópico intracraniano tenha sido realizado no início do século 20, esta técnica tornou-se popular entre os neurocirurgiões, somente nos anos recentes, após o refinamento dos endoscópios e de seus instrumentos. Mesmo com o uso de microscópios, as vezes as relações entre os aneurismas e as estruturas vizinhas não é claramente definida. A visão reta oferecida pelo microscópio resulta em visualização inadequada de estruturas que se colocam imediatamente atrás, como o colo, ramos ou perfurantes do aneurisma. Assim, a exposição destas estruturas pode requerer retrações de risco para a artéria aferente ou o próprio aneurisma, o que pode ser superado por uma clara informação anatômica obtida com o endoscópio, ao invés de uma eventual manipulação externa com o microscópio. O endoscópio permite “close-up”, amplas e anguladas observações das características anatômicas e verificação do posicionamento ótimo do clipe. A conformação visual da anatomia regional obtida com o uso do endoscópio rígido oferece aliosa informação para subseqüentes e a confiabilidade. Microscopia assistida por endoscopia é um auxílio excepcional, e o uso de tecnologia PIP (quadro a quadro), permite a observação simultânea das imagens no microscópio e no endoscópio, através da ocular do microscópio. As vantagens da neuroendoscopia incluem a habilidade de olhar em volta de ângulos e atrás de obstáculos. Com menos retração cerebral, menores abordagens e melhor visualização, a neuroendoscopia pretende reduzir a morbidade operatória. Para tal, o neurocirurgião deve estar familiarizado com a técnica e preparado para os inconvenientes e riscos do procedimento.