Indocyanine green videoangiography methodological variations: review

Abstract

Indocyanine green videoangiography (ICGVA) procedures have become widespread within the spectrum of microsurgical techniques for neurovascular pathologies. We have conducted a review to identify and assess the impact of all of the methodological variations of conventional ICGVA applied in the field of neurovascular pathology that have been published to date in the English literature. A total of 18 studies were included in this review, identifying four primary methodological variants compared to conventional ICGVA: techniques based on the transient occlusion, intra-arterial ICG administration via catheters, use of endoscope system with a filter to collect florescence of ICG, and quantitative fluorescence analysis. These variants offer some possibilities for resolving the limitations of the conventional technique (first, the vascular structure to be analyzed must be exposed and second, vascular filling with ICG follows an additive pattern) and allow qualitatively superior information to be obtained during surgery. Advantages and disadvantages of each procedure are discussed. More case studies with a greater number of patients are needed to compare the different procedures with their gold standard, in order to establish these results consistently.

Novel Classification of Early-stage Systemic Hypertensive Changes in Human Retina Based on OCTA Measurement of Choriocapillaris

“…ICGA imaging is unable to individually evaluate blood flow or separate the choriocapillaris vasculature from the retinal and choroidal vasculature. Furthermore, ICGA is an invasive technique that requires intravenous dye injections, and it may cause mild or severe adverse reactions occasionally 34 , 35 . Optical coherence tomography angiography (OCTA) is a recently introduced state-of-the-art technique that can detect the movement of erythrocytes in the vascular network and can provide non-invasive imaging of the microvascular network without the use of dye injections 25 , 26 , 36 , so its application is not limited by contraindications to the dye.…”

The role of indocyanine green fluorescence in endoscopic endonasal skull base surgery and its imaging correlations

“…7 The correlation between the MRI enhancement and the ICG fluorescence pattern has been either or unclearly mentioned in previous articles. 2,9,[17][18][19]27 To our knowledge, objective quantification of endoscopic ICG fluorescence was never correlated with the SI of MRI enhancement in the literature before the present study.…”

“…31 More technical advancement to help detect minor differences in the fluorescence will help in the differentiation of similarly fluorescent structures, especially in the cases of the pituitary adenomas. Different systems 32 and techniques 27 can affect the ability to visualize ICG microscopically and consequently endoscopically. Real-time intraoperative correlation between the fluorescence and the enhancement may help in improving interpretation of the ICG scenes.…”

Quantification of fluorescence angiography: Toward a reliable intraoperative assessment of tissue perfusion - A narrative review

“…From this FTC, a range of different of Q-ICG parameters can be calculated, reflecting tissue perfusion [18]. Several Q-ICG parameters have been evaluated and have shown exciting results in the fields of plastic surgery [27,28], ophthalmic surgery [29], and neurosurgery [30,31]. These results conclude that Q-ICG is an accurate, objective, and unbiased method of perfusion assessment.…”