Microsurgical Clipping of Carotid-Ophthalmic Tandem Aneurysms: Case Report and Surgical Nuances

External carotid artery-radial artery graft-posterior cerebral artery bypass for complex vertebrobasilar aneurysms: efficacy and analysis of outcome in a single center

The purpose of this research was to demonstrate the effectiveness and clinical outcome of an external carotid artery-radial artery graft-posterior cerebral artery (ECA-RAG-PCA) bypass in the treatment of complex vertebrobasilar artery aneurysms (VBANs) in a single-center retrospective study. An ECA-RAG-PCA bypass may be a last and very important option in the treatment of complex VBANs when conventional surgical clipping or endovascular interventions fail to achieve the desired outcome. This study retrospectively analyzed the clinical presentation, case characteristics, aneurysm location, size and morphology, choice of surgical strategy, complications, clinical follow-up, and prognosis of the patients enrolled. The data involved were analyzed by the appropriate statistical methods. A total of 24 patients with complex VBANs who met the criteria were included in this study. Eighteen (75.0%) were male and the mean age was 54.1 ± 8.83 years. The aneurysms were located in the vertebral artery, the basilar artery, and in the vertebrobasilar artery with simultaneous involvement. All patients underwent ECA-RAG-PCA bypass surgery via an extended middle cranial fossa approach, with 8 (33.3%) undergoing ECA-RAG-PCA bypass only, 3 (12.5%) undergoing ECA-RAG-PCA bypass combined with aneurysm partial trapping, and 12 (50.0%) undergoing ECA-RAG-PCA bypass combined with proximal occlusion of the parent artery. The average clinical follow-up was 22.0 ± 13.35 months. The patency rate of the high-flow bypass was 100%. At the final follow-up, 15 (62.5%) patients had complete occlusion of the aneurysm, 7 (29.2%) patients had subtotal occlusion of the aneurysm, and 2 (8.3%) patients had stable aneurysms. The rate of complete and subtotal occlusion of the aneurysm at the final follow-up was 91.7%. The clinical prognosis was good in 21 (87.5%) patients and no procedure-related deaths occurred. Analysis of the good and poor prognosis groups revealed a statistically significant difference in aneurysm size (P = 0.034, t-test). Combining the results of this study and the clinical experience of our center, we propose a surgical algorithm and strategy for the treatment of complex VBANs.The technical approach of ECA-RAG-PCA bypass for complex VBANs remains important, even in an era of rapid advances in endovascular intervention. When conventional surgical clipping or endovascular intervention has failed, an ECA-RAG-PCA bypass plays a role that cannot be abandoned and is a very important treatment option of last resort.

Strategies for Treatment of Multiple Brain Aneurysms Without Intraoperative Adjuncts

BACKGROUND

Although fairly rare, multiple brain aneurysms are well known to occur in certain conditions such as arteriovenous malformations, coarctation of the aorta, renal artery stenosis, adult type 3 polycystic kidney disease, as well as connective tissue disorders (such as Ehlers-Danlos syndrome, Marfan syndrome, and fibromuscular dysplasia). Increased incidence of complications of surgery in such situations is expected to be more likely than in surgery for a single aneurysm, particularly in the absence of intraoperative guidance with adjuncts.

METHODS

We report a case of an anterior communicating artery aneurysm, a right middle cerebral artery aneurysm, and a right pericallosal aneurysm in a 70-year-old man. All 3 aneurysms were clipped through a single-stage approach without the aid of any adjuncts such as micro-Doppler ultrasonography, indocyanine green videoangiography, or intraoperative digital subtraction angiography. We carried out a literature review for past publications on similar reports.

RESULTS

The patient made a complete postoperative recovery and sustained no neurologic deficits. Out of 388 publications from the literature search, only 1 case report described clipping of 2 tandem aneurysms in a 60-year-old woman without mentioning any intraoperative adjuncts.

CONCLUSIONS

This case illustrates that multiple aneurysms can actually be safely operated with adequate planning in the absence of these adjuncts, especially in resource-poor regions. This is particularly crucial in Africa and most low-and-middle-income countries, where such facilities and equipment are not common.

Cranio-Orbito-Zygomatic Approach: Core Techniques for Tailoring Target Exposure and Surgical Freedom

Background: The cranio-orbito-zygomatic (COZ) approach is a workhorse of skull base surgery, and each of its steps has a precise effect on target exposure and surgical freedom. The present study overviews the key techniques for execution and tailoring of the COZ approach, focusing on the quantitative effects resulting from removal of the orbitozygomatic (OZ) bar, orbital rim, and zygomatic arch. Methods: A PRISMA-based literature review was performed on the PubMed/Medline and Web of Science databases using the main keywords associated with the COZ approach. Articles in English without temporal restriction were included. Eligibility was limited to neurosurgical relevance. Results: A total of 78 articles were selected. The range of variants of the COZ approach involves a one-piece, two-piece, and three-piece technique, with a decreasing level of complexity and risk of complications. The two-piece technique includes an OZ and orbitopterional variant. Superolateral orbitotomy expands the subfrontal and transsylvian corridors, increasing surgical freedom to the basal forebrain, hypothalamic region, interpeduncular fossa, and basilar apex. Zygomatic osteotomy shortens the working distance of the pretemporal and subtemporal routes. Conclusion: Subtraction of the OZ bar causes a tremendous increase in angular exposure of the subfrontal, transsylvian, pretemporal, and subtemporal perspectives avoiding brain retraction, allowing for multiangled trajectories, and shortening the working distance. The COZ approach can be tailored based on the location of the lesion, thus optimizing the target exposure and surgical freedom and decreasing the risk of complications.

Optic Foraminotomy for Clipping of Superior Carotid-Ophthalmic Aneurysms

Background: Carotid-ophthalmic aneurysms usually cause visual problems. Its surgical treatment is challenging because of its anatomically close relations to the optic nerve, carotid artery, ophthalmic artery, anterior clinoid process, and cavernous sinus, which hinder direct access. Despite recent technical advancements enabling risk reduction of this complication, postoperative deterioration of visual function remains a significant problem. Therefore, the goal of preserving and/or improving the visual outcome persists as a paramount concern. Objective: We propose optic foraminotomy as an alternative microsurgical technique for dorsal carotid-ophthalmic aneurysms clipping. As a secondary objective, the step by step of that technique and its benefits are compared to the current approach of anterior clinoidectomy. Methods: We present as an example two patients with superior carotid-ophthalmic aneurysms in which the standard pterional craniotomy, transsylvian approach, and optic foraminotomy were performed. Surgical techniques are presented and discussed in detail with the use of skull base dissections, microsurgical images, and original drawings. Results: Extensive opening of the optic canal and optic nerve sheath was successfully achieved in all patients allowing a working angle with the carotid artery for correct visualization of the aneurysm and further clipping. Significant visual acuity improvement occurred in both patients because of decompression of the optic nerve. Conclusion: Optic foraminotomy is an easy and recommended technique for exposing and treating superior carotid-ophthalmic aneurysms and allowing optic nerve decompression during the first stages of the procedure. It shows several advantages over the current anterior clinoidectomy technique regarding surgical exposure and facilitating visual improvement.

Pterional Approach

The pterional approach is a workhorse in neurosurgery, to the point where perfect knowledge of its execution is essential in neurosurgical daily practice. The pterional transsylvian corridor is used to treat aneurysms involving anterior circulation, basilar apex, the proximal segment of the superior cerebellar and posterior cerebral artery, arteriovenous malformations and cavernous hemangiomas of the basal forebrain, anterior and middle skull base tumors, gliomas of the frontal, parietal, and temporal opercula, insula, mediobasal temporal region, cerebral peduncles, interpeduncular fossa, and also orbital lesions. We herein overview the core technique and variations of the pterional approach aimed at broadening surgical freedom and decreasing the risk of approach-related complications.