Intraoperative monitoring by imaging and electrophysiological techniques during giant intracranial aneurysm surgery

Comparative Study of Intraoperative Fluorescein and Indocyanine Green Videoangiography for Ruptured Cerebral Aneurysms Clipping: A Single Centre Study of 30 Cases

Aim This study assesses the application of microscope integrated videoangiography techniques in aneurysm clipping surgery using Indocyanine Green and Fluorescein fluorophores and evaluates merits and demerits of each technique.

Materials and Methods Total 30 patients of cerebral aneurysmal clipping were included. Standard microsurgical procedures were done. After clipping, we administered a 25 mg bolus intravenous dose of indocyanine green with microscope focused through the INFRARED 800 camera module, followed by administration of 60 mg bolus intravenous dose of fluorescein with microscope focused through the yellow 560 module and images were assessed.

Results The average aneurysm size was 17 mm. In 12 patients (40%), FL-VA allowed better assessment of perforating arteries (seven cases) or distal branches (three cases) or both (two cases), when compared with ICG-VA. In one case of MCA (M1) aneurysm, ICG-VA showed no fluorescent signal in one of the distal trunks whereas FL-VA showed normal signal. In one case of ACOM aneurysm, perforators were missed on ICG-VA but were seen on FL-VA. FL-VA was able to identify inadequate aneurysm clipping in one case. In two patients, FL-VA provided the advantage of real-time manipulation of the vessels to expose the vessels and aneurysms of interest. Fluorescein detected all the perforators that were visible under white light (68/68) whereas ICG was able to detect 56 (82.35%) perforators (p-value< 0.05).

Conclusion Intraoperative ICG and Fluorescein videoangiography recognize inadequate occlusion of aneurysm, decreased flow in branches or perforators. When various study parameters were considered such as ability to assess small size perforators, branching vessels, adequacy of aneurysmal clipping, and useful information on repeat imaging, FL-VA was found superior to ICG-VA.

Reconstruction clipping of ruptured anterior circulation aneurysms via supraorbital lateral keyhole approach

Background

Intracranial aneurysm (IA) is a serious disease. Analyze and review the cases of anterior circulation ruptured IA by supraorbital lateral keyhole approach, and summarize the experiences of this approach.

Methods

Retrospective analysis of 16 cases of ruptured anterior circulation IA in our department from January 2019 to June 2020, CT angiography (CTA) was performed before operation. Analyzing the IA’s parameters by 3D-CT reconstruction. The IA was clipped by supraorbital lateral keyhole approach combined with the 3D-skull reconstruction. Extraventricular drainage was performed before craniotomy. Intraoperative neurophysiological monitoring was performed during the operation. After operation, fluorescein angiography and vascular ultrasound were performed to check the clipping effect. Intracranial pressure monitor was performed postoperatively. CTA was reexamined one week after operation. The modified Rankin Scale (MRS) was performed 6 months after operation.

Results

There were 7 males (43.8%) and 9 females (56.2%), and the average age is 52.31 ± 11.12 years old. Among them, 11 patients (68.8%) were anterior communicating artery aneurysms and 5 (31.2%) were middle cerebral artery aneurysms. All patients were out of hospital within 10 days without any death, without cerebral infarction, cerebrospinal fluid leakage and neurological impairments. About mRS score, after 6 months follow-up, 8 cases (50%) had 0 point, 4 cases (25%) had 1 point, and 4 cases (25%) had 2 points.

Conclusions

For ruptured anterior circulation IA, the supraorbital lateral keyhole approach combined with ventricular drainage, intraoperative electrophysiological monitoring, and intraoperative vascular ultrasound is a safe and minimally invasive treatment. The application of reconstruction clipping can reconstruct the diameter of parent vessel and reduce the recurrence rate of IA.