Application of indocyanine green video angiography in surgical treatment of intracranial aneurysms

Abstract

Indocyanine green (ICG) video angiography has been used for several medical indications in the last decades. It allows a real time evaluation of vascular structures during the surgery 1,2,3,4,5 . Indocyanine green dye was developed for near-infrared photography by the Kodak Research Laboratories in 1955 and was already approved for clinical use in 1956. However, it was used for angiography in the 60´s and for retinal angiography in the 70´s. The principle of fluorescence imaging used in ICG is simple: illuminate the tissue of interest with light at the excitation wavelength (800 nm) while observing it at longer emission wavelengths (over 800 nm) 1,2,3,4,5 .Neurosurgery is ideal for ICG because operations are already done using microscope (and camera), and because the blood vessels located on the brain surface are exposed and thus can be seen more or less directly by visual means. Thus, ICG applied in vascular neurosurgical procedures has emerged as a valuable option to assess intraoperatively details of aneurysmal clipping 4,5,6,. Although with increasing reports of ICG application, there are still some points to be discussed. Additionally, Brazilian literature has no publication about such theme to the best of our knowledge. We report below the first Brazilian experience with application of ICG in the treatment of intracranial aneurysms 4,5,6 . AbstrActIndocyanine green (ICG) video angiography has been used for several medical indications in the last decades. It allows a real time evaluation of vascular structures during the surgery. This study describes the surgical results of a senior vascular neurosurgeon. We retrospectively searched our database for all aneurysm cases treated with the aid of intraoperative ICG from 2009 to 2014. A total of 61 aneurysms in 56 patients were surgically clipped using intraoperative ICG. Clip reposition after ICG happened in 2 patients (3.2%). Generally, highly variable clip adjustment rates of 2%-38% following ICG have been reported since the introduction of this imaging technique. The application of ICG in vascular neurosurgery is still an emerging challenge. It is an adjunctive strategy which facilitates aneurismal evaluation and treatment in experienced hands. Nevertheless, a qualified vascular neurosurgeon is still the most important component of a high quality work.Keywords: aneurysm, treatment, surgery, indocyanine green. resumo A angiografia intraoperatória com indocianina verde (ICG) já foi aplicada em diversas situações clínicas por vários anos. O ICG permite avaliação em tempo real de estruturas vasculares durante a cirurgia. Este artigo descreve os resultados cirúrgicos do autor sênior. Avaliamos retrospectivamente os casos de aneurismas intracranianos operados de 2009 a 2014. Um total de 61 aneurismas em 56 pacientes foram operados com ICG. O reposicionamento do clip ocorreu em 2 casos (3.2%). Geralmente, taxas variáveis de reposicionamento do clip têm sido descritas (2%-38%). A aplicação de ICG na neurocirurgia vascular ainda é um desafio crescente. É um artifí...

Assessing aneurysm obliteration and neck remnants in 225 clipped aneurysms using icg-va, mdusg, and postoperative dsa

“…Microscope-integrated near-infrared ICG-VA has been used regularly and widely in neurovascular surgery for several years (2,6,16,22,(26)(27)(28)34,35). It is accepted as a convenient adjunct for assessing cerebral blood flow during surgery for cerebral aneurysms, cerebral arteriovenous malformations (AVMs), and extracranial-intracranial bypass (2,22,30,39,41).…”

“…ICG-VA is an ideal indicative tool for surgery before the occurrence of vascular-cerebral injury. The speed of image acquisition, convenience of usage during surgery, and improved resolution to assess even small perforating arteries are major advantages of this method (7,13,16,28). On the other hand, false-negative ICG-VA findings must be kept in mind (12).…”

“…Intraoperative DSA remains the gold standard for the evaluation of residual filling. However, the dependency on a neurovascular team during surgery and the long time required for the procedure cause DSA to be far from practical (11,25,28,40).…”

“…The superiority rate of dome puncturing over ICG-VA was 1.6%. reduce the efficacy of ICG-VA as a diagnostic tool (7,21,28). Conversely, MDUSG, especially with thin probes, is feasible to assess the aneurysm dome and parent artery even in deep areas and with the presence of overlaying vessels, cisternal blood and existence of complex geometrical shapes.…”

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

“…They may also be classified according to the fundus/neck ratio and their content (thrombosed, partially thrombosed or calcified). [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] 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.…”