Endoscope-assisted microneurosurgery for intracranial aneurysms

Clipping aneurysms via a fully endoscopic transcranial approach

Here we presented the initial experience of clipping aneurysms using fully endoscopic techniques and aimed to evaluate the safety and feasibility of fully endoscopic techniques for aneurysms. This was a retrospective single-center study in which patients were scheduled to undergo aneurysm clipping using fully endoscopic techniques. We collected patients' records, radiological neuroimaging, aneurysm-related variables and surgical procedures in detail, as well as postoperative outcomes. All patients were followed up for neurological examinations and computed tomography (CT) as well as computed tomography angiography (CTA) regularly after surgery. We reviewed the radiological and clinical data of 7patients who underwent aneurysm clipping via fully endoscopic techniques at our department from Jan. 2022 to Jul. 2024, including 2 middle cerebral artery aneurysms, 3 cerebral anterior communicating artery aneurysms, 1 anterior cerebral aneurysm and 1 ophthalmic aneurysm. No uncontrolled rupture of aneurysm occurred during operation. Postclipping endoscopic inspection as well as postoperative CTA demonstrated complete occlusion of the aneurysm and preservation of parent, branching, and perforating vessels. None postclipping cerebral infarction caused by branch or perforator compromise were observed after clipping. No mortality was recorded. Follow-up ranged from 1 to 10 months. Six patients (71.4%) showed excellent or good recoveries. The remaining patient recorded improved KPS. With the accumulation of experience and technological progress, the fully endoscopic technique could enable safe and effective clipping of an aneurysm, which provided valuable information for decision-making during surgery and shed a new light on aneurysms clipping.

Endoscopic Eyebrow Approach for Aneurysms

INTRODUCTION

Considerable effort has been made to reduce surgical invasiveness, since Axel Perneczky introduced the supraorbital eyebrow approach as a core part of his keyhole concept in neurosurgery. But a limited approach does not facilitate an already serious and demanding task as aneurysm surgery. In this regard, the enhancement of the visual field before, during, and after microsurgical aneurysm occlusion is a safe and effective method to increase the quality of treatment. Indications/Contraindications: Based on the individual anatomical findings, the supraorbital keyhole approach provides access to most aneurysms of the anterior circulation. The approach is not recommended in large complex aneurysms, giant aneurysms, BA aneurysms located beneath the dorsum sellae, as well as cases of severe subarachnoid hemorrhage (SAH) and expected brain edema.

COMPLICATIONS

Experience with endoscopic procedures in aneurysm surgery is limited to several clinical retrospective articles, and no major complications in conjunction with the endoscope were observed. Outcome and Prognosis: The supraorbital eyebrow approach has a low rate of complications and provides highly favorable cosmetic results. Endoscopic inspection prior to clipping might reduce overexposure and mobilization of the aneurysm. It was found that the rate of intraoperative rupture was decreased. The endoscopic post-clipping control helped significantly to reduce aneurysm remnants and unattended parent, branch, or perforator occlusion.

CONCLUSION

The supraorbital eyebrow approach is a safe, effective and elegant approach in the treatment of most aneurysms of the anterior circulation. The additional enhancement of the visual field provided by the endoscope before, during, and after microsurgical aneurysm clipping might decrease the rate of intraoperative aneurysm ruptures and unexpected findings concerning aneurysm remnant occlusion and compromise of involved parent, branching, and perforating vessels.

Endoscope-assisted microneurosurgery for intracranial aneurysms: A systematic review and meta-analysis

BACKGROUND

In the surgical approach to treat deep-seated intracranial lesions, endoscopes can be used to assist microsurgical operations and improve outcomes. This technique is often called endoscope-assisted microneurosurgery (EAM). This systematic review and meta-analysis aimed to evaluate the feasibility, safety, and effectiveness of EAM.

METHODS

We performed a meta-analysis of relevant articles identified using PubMed, Embase, and the Cochrane Central Register to assess the efficacy of EAM according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Primary outcomes were repositioning of the definitive clip, better surgical field, the overall and endoscope-related complication rates, mortality, and the rate of follow up.

RESULTS

A total of 10 studies of 1,432 patients with 1,717 aneurysms treated with EAM were included. EAM led to repositioning of the definitive clip in 13% (95% CI, 9%-17%; I₂ = 72.61%; p < 0.001); 77% of aneurysms treated with endoscopically assisted vision and information had a better outcome than that with standard surgery (95% CI, 52%-95%; I₂ = 97.63%; p < 0.001). There was an overall complication rate of 6% (95% CI, 1%-13%; I₂ = 91.39%; p < 0.001). The incidence of endoscope-related complications was 0% (95% CI, 0%-1%; I₂ = 64%; p < 0.001). The mortality was 0% (95% CI, 0-1%; I₂ = 0.0%); and 94% of patients had an excellent to good recovery and good outcome (95% CI, 88%-98%; I₂ = 88.42%; p < 0.001).

CONCLUSIONS

Our comprehensive study showed that EAM for intracranial aneurysms is feasible, the safety of the surgery is good, and the patients have a good prognosis, Therefore, we think EAM can be more widely adopted in the future.

Intraoperative Use of Endoscope, a Valuable, Adjunctive Tool for the Surgical Management of Anterior Communicating Artery Aneurysm Surgery: Our Institutional Experience

Background:

Anterior communicating (A-com) artery region is very complex; perforators are not always visualized on the microscope. The neuroendoscope with its higher magnification, better observation, and additional illumination can provide us information that may not be available with the microscope in aneurysm surgery.

Objective:

The objective was to study the use of endoscope in surgical management of A-com aneurysm surgery and its advantages, whether and how it changes operative management.

Materials and Methods:

We studied 25 serial cases of A-com aneurysm at Bantane Hospital, Fujita University, Japan, from November 2018 to October 2019. Once aneurysm was exposed, we did preclipping indocyanine green (ICG) study and examination with endoscope. After clipping, we again did ICG and endoscopic assessment. Preclipping and postclipping endoscopic information was used and necessary changes were made in the operative decisions. Whether endoscope gives any additional information over microscope and ICG which led to change in the operative decision was assessed.

Results:

In six out of 25 A-com aneurysm patients, the use of endoscope has given additional information over microscope, and ICG leading to change in the operative plans such as readjustment of the clip/application of the second clip or release of perforator compromise.

Conclusion:

Simultaneous endoscopic and microscopic guidance can reveal important information hidden from the microscope. Thus, this method increases the safety and durability of the A-com aneurismal clipping.

Use of our Protocol of Multimodality Tools to Aid in the Safe Microsurgical Clipping of Unruptured Anterior Circulation Aneurysms

OBJECTIVES

The aim of this study is to analyze the effectiveness of our protocol of the use of multimodality tools, namely indocyanine green-dual image video angiography, neuroendoscope, neuromonitoring with motor-evoked potential, micro-Doppler in the microsurgical clipping of unruptured anterior circulation aneurysms, operated at our institute from January 2016 to December 2018.

MATERIALS AND METHODS

We performed a retrospective analysis of all cases of unruptured anterior circulation aneurysms, operated at Fujita Health University Banbuntane-Hotokukai Hospital, Japan, from January 2016 to December 2018. We assessed outcome at immediate postoperative, at discharge, and at 3 months follow-up by defining permanent morbidity as drop in Modified Rankin Scale (MRS) by 1 at 3 months follow-up and transient morbidity as temporary deficit that improved at discharge or follow-up. Postoperative events, namely seizures, infection that did not affect/change. Preoperative MRS and discharge timing were excluded. We concluded poor outcome as MRS ≥3 and good outcome as MRS < 3 (0-2). All patients had a minimum of 3 months follow-up before outcome conclusion.

RESULTS

In 2016, a total of 98 cases were operated with no mortality or permanent morbidity (i.e., change in preoperative MRS), only transient morbidity was seen in (two cases) 2.04%. In 2017, a total of 119 cases were operated with no mortality or morbidity. In 2018, a total of 130 cases were operated with no mortality or permanent morbidity, only transient morbidity 0.7%. Summarizing from January 2016 to December 2018, a total of 347 cases of anterior circulation aneurysms were operated. Mostly, in the female sex (73.3%), the most common was middle cerebral artery aneurysm (39.1%). The mean size was 5.3 mm with no mortality or permanent morbidity with only transient morbidity in 0.9%. No poor outcome (MRS ≥3) was seen in our series.

CONCLUSION

In our center for most unruptured anterior circulation aneurysms, microsurgical clipping is the treatment of choice. We believe our protocol of the intra-operative usage of multimodality tools have aided in the safe microsurgical clipping and have consistently resulted in good operative outcomes. Hence, we recommend and continue to use our Fujita-Bantane Protocol in all cases of micro-surgical clipping of aneurysms to consistently achieve good operative outcomes.

Endoscopic Endonasal Transclival Approach versus Dual Transorbital Port Technique for Clip Application to the Posterior Circulation: A Cadaveric Anatomical and Cerebral Circulation Simulation Study

Purpose  Simulation training offers a useful opportunity to appreciate vascular anatomy and develop the technical expertise required to clip intracranial aneurysms of the posterior circulation. Materials and Methods  In cadavers, a comparison was made between the endoscopic transclival approach (ETA) alone and a combined multiportal approach using the ETA and a transorbital precaruncular approach (TOPA) to evaluate degrees of freedom, angles of visualization, and ergonomics of aneurysm clip application to the posterior circulation depending on basilar apex position relative to the posterior clinoids. Results  ETA alone provided improved access to the posterior circulation when the basilar apex was high riding compared with the posterior clinoids. ETA + TOPA provided a significantly improved functional working area for instruments and visualization of the posterior circulation for a midlevel basilar apex. A single-shaft clip applier provided improved visualization and space for instruments. Proximal and distal vascular control and feasibility of aneurysmal clipping were demonstrated. Conclusions  TOPA is a medial orbital approach to the central skull base; a transorbital neuroendoscopic surgery approach. This anatomical simulation provides surgical teams an alternative to the ETA approach alone to address posterior circulation aneurysms, and a means to preoperatively prepare for intraoperative anatomical and surgical instrumentation challenges.

The Clinical Importance of Perforator Preservation in Intracranial Aneurysm Surgery: An Overview with a Review of the Literature

Clipping for intracranial aneurysms is done to achieve complete occlusion of the aneurysm without a remnant sac. Despite modern advancements of neurosurgical techniques, morbidity related to the clipping of intracranial aneurysms still exists. Clip occlusion of a parent artery or small hidden perforators commonly leads to permanent neurological deficits, and is a serious and unwanted complication. Thus, preserving blood flow in the branches and perforators of a parent artery is very important for successful surgery without postoperative morbidity and mortality. The aim of this review article is to discuss the consequences of perforator injury and how to avoid this phenomenon in aneurysm surgeries using intraoperative monitoring devices.

The Roles of Endoscope in Aneurysmal Surgery

The neuroendoscope, with its higher magnification, better observation, and additional illumination, can provide us information that may not be available with the microscope in aneurysm surgery. Furthermore, recent advancement of the holding systems for the endoscope allows surgeons to perform microsurgical manipulation using both hands under the simultaneous endoscopic and microscopic monitoring. With this procedure, surgeons can inspect hidden structures, dissect perforators at the back of the aneurysm, identify important vessel segments without retraction of the aneurysm or arteries, and check for completion of clipping. In addition, we have recently applied endoscopic indocyanine green video angiography to aneurysm surgery. This newly developed technique can offer real-time assessment of the blood flow of vasculatures in the dead angles of the microscope, and will reduce operative morbidity related to vascular occlusion, improve the durability of aneurysm surgery by reducing incomplete clipping, and thus promote the outcome of aneurysm surgery.