Inappropriate application of Yaşargil aneurysm clips: a new observation and technical remark

ICGA combined with EP monitoring in microclipping of cerebral aneurysms

Cerebral aneurysm is one of the common cerebrovascular diseases in neurosurgery, and rupture of cerebral aneurysm is the most important cause of spontaneous subarachnoid hemorrhage. How to precisely clip the aneurysm has been a topic worth discussing, so the authors explore the value of ICGA combined with electrophysiological monitoring in the microclipping of cerebral aneurysms. Using the method of retrospective analysis of cases, 661 patients with cerebral aneurysms admitted to the Department of Neurosurgery, Zhongnan Hospital of Wuhan University, from 2021.8 to 2022.10 were studied, 390 patients with aneurysm clipping were included, and patients with Hunt-Hess classification ≥ 4 were excluded, and whether to use ICGA combined with EP in microclipping of the ruptured and unruptured aneurysm in pterional approach was investigated at the time of discharge, respectively. The MRS and total hospital days were compared to investigate the value of ICGA combined with EP in the microclipping of cerebral aneurysms. All 390 patients enrolled in the group had successful aneurysm clipping, 178 patients were screened for ruptured aneurysm pterional approach and 120 patients for unruptured aneurysm pterional approach access; the MRS at discharge was significantly lower in the ICGA combined with EP group than in the no-EP group for ruptured aneurysm pterional approach microclipping (p < 0.001), and the mean number of days in hospital was significantly lower (p < 0.01). Patients in the ICGA combined with EP group in microclipping of unruptured aneurysms with pterional approach also had significantly lower MRS at discharge compared with patients in the ICGA alone group (p < 0.001), with no statistically significant difference in the mean number of days in hospital (p = 0.09). In open cerebral aneurysm microclipping, ICGA combined with EP monitoring for both ruptured and unruptured aneurysms can effectively reduce the false-negative rate of ICGA, significantly reduce the incidence of postoperative neurological deficits, and shorten the total hospital stay to some extent. ICGA combined with EP monitoring may be an effective means to reduce the rate of false clipping of the penetrating vessels and to avoid stenosis or occlusion of the aneurysm-carrying artery and is worth promoting in microclipping of cerebral aneurysms except for Hunt-Hess ≥ 4.

Intraoperative Combined Use of Somatosensory Evoked Potential, Microvascular Doppler Sonography, and Indocyanine Green Angiography in Clipping of Intracranial Aneurysm

Background

The aim of this study was to evaluate the effect of combining application of somatosensory evoked potential (SEP), microvascular Doppler sonography (MDS), and indocyanine green angiography (ICGA) in intracranial aneurysm clipping surgery.

Material/Methods

A total of 158 patients undergoing an intracranial aneurysm clipping operation were recruited. All patients were evaluated with intraoperative SEP and MDS monitoring, and 28 of them were evaluated with intraoperative combined monitoring of SEP, MDS, and ICGA.

Results

The SEP waves dropped during temporary occlusion of arteries in 19 cases (12.0%), and returned to normal after the clips were repositioned. After aneurysms were clipped, the vortex flow signals were detected by MDS in 6 cases. The aneurysm neck remnants were detected by ICGA in 2 cases of olfactory artery (OA) and in 1 case of middle cerebral artery (MCA), which disappeared after the clips were repositioned. Postoperative CTA or DSA showed that aneurysms were clipped completely and parent arteries and perforating vessels were patent. GOS at 1 month after the surgery was good in 111 cases (70.3%), mild disability in 22 cases (13.9%), severe disability in 14 cases (8.9%), vegetative state in 5 cases (3.2%), and death in 6 cases (3.8%).

Conclusions

Intraoperative combining application of SEP, MDS, and ICGA can reduce brain tissue ischemia and damage and disability and mortality rate after effective clipping of intracranial aneurysms, thereby improving surgical outcomes.

The efficiency of the new Yasargil titanium fenestrated mini-clips for ideal clipping of a cerebral aneurysm

BACKGROUND

The fenestrated clip is sometimes useful in limited approach angle and narrow working space. However, before the development of the new Yasargil titanium fenestrated mini-clip, the only variations of fenestrated clips were those of larger sizes. And those larger clips have a problem of the triangle-shaped gap at the proximal end of the blade. The authors describe the efficiency, limitations and surgical technique of using the Yasargil titanium fenestrated mini-clip.

METHODS

Fifty-nine cases of aneurysms were treated using these mini-clips. Aneurysm location, size and dome neck ratio, mean follow-up period, neck remnant, and recurrence rate were also analyzed. Among these cases, we present eight characteristic cases, including a case with aneurysm recurrence, and we review the problems associated with the triangle-shaped gap at the proximal end of the clip.

RESULTS

The average size of the aneurysms was 5.57 mm, and the dome neck ratio was >2.0 in 1.69%, >1.5 in 11.8%, >1.2 in 35.6%, and <1.2 in 50.8% of cases. The mean follow-up period for the 59 cases was 5.5 months (range, 0.5-16 months). Angiographic recurrence of the treated portion occurred in 1 case (1.7%), including an aneurysm in the basilar artery tip aneurysm.

CONCLUSION

The availability of the Yasargil titanium fenestrated mini-clip increases the options for clipping to minimize the remnant of the clipped aneurysm. However, there is still concern over the triangular space at the base of the blade, especially when treating an aneurysm with a thin vessel wall. Therefore, modification of the clipping technique is sometimes needed.

Indocyanine green videoangiography methodological variations: review

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.

How reliable and accurate is indocyanine green video angiography in the evaluation of aneurysm obliteration?

INTRODUCTION

Indocyanine green video angiography (ICG-VA) has been recently introduced into neurovascular surgery and gained a role in assessing vessel patency and obliteration of intracranial aneurysms (IA) after clipping. Although its correlation with intra-postoperative angiography was demonstrated in previous studies, difficulties in evaluating aneurysm obliteration have not been reported. We report reliability and accuracy of ICG-VA in 109 clipped aneurysms with attention given to five cases in which ICG-VA evaluation resulted in false indication that aneurysms were secure in terms of complete obliteration.

MATERIALS AND METHODS

A retrospective chart review was performed of IAs surgically treated by a single surgeon from January 2009. In all cases, aneurysm obliteration was confirmed by a combination of microdoppler ultrasonography (MUSG), ICG-VA, and post-operative angiography.

RESULTS

ICG-VA appropriately assessed vessel patency and aneurysm obliteration in 93.5% of aneurysms clipped. In four cases (3.6%), puncturing the dome of the aneurysm after satisfactory clipping revealed persistent flow within the aneurysm despite ICG-VA showing no flow after clipping. In one case (0.9%), ICG-VA showed persistent flow within the aneurysm and MUSG did not, and puncture of the dome confirmed no flow within the aneurysm. In one case (0.9%), ICG-VA failed to demonstrate residual neck.

CONCLUSION

ICG-VA is a simple and safe procedure and an important adjunct to microsurgical clipping of aneurysm. Although ICG-VA assesses vessel patency and obliteration of aneurysms in most cases, applying the principles of microsurgery in aneurysm clipping remains a main tool for obtaining the complete obliteration of aneurysm along with preservation of the normal vasculature.