Rescue bypass for the treatment of pseudoaneurysm on the distal anterior cerebral artery: a case report of vertical side-to-side anastomosis of the distal callosomarginal artery-pericallosal artery

Pericallosal artery aneurysms: an evidence-based analysis of clinical presentations, therapeutic approaches, and outcome

Pericallosal artery aneurysms (PCAA) are relatively rare intracranial aneurysms that present unique challenges in diagnosis and management. This study provides a comprehensive review of the literature to assess demographic patterns, risk factors, treatment approaches, and complications associated with PCAA. Data from 23 studies were analyzed using Python with libraries such as Pandas and Matplotlib. Descriptive statistics and crosstabulations explored the relationships between treatment modalities (microsurgical, endovascular, combined) and complications, including hydrocephalus, vasospasms, and intraprocedural ruptures. Visualizations were employed to depict the prevalence and impact of various outcomes. Analysis revealed a notable gender disparity, with females constituting 70.47% of the study population. The average age was 49.93 years, and the average aneurysm size was 6.34 mm. A majority of aneurysms were ruptured (542 ruptured vs. 251 unruptured). Risk factors like smoking were prevalent, and radiological features such as subarachnoid hemorrhage (SAH) were commonly reported. Endovascular treatment was slightly more frequent (86.96%) than microsurgical treatment (73.91%). Vasospasm was the most reported complication (56.5%), followed by hydrocephalus and intraprocedural rupture. The analysis of the distribution of studies reporting complication for each treatment modality showed that endovascular treatment studies reported higher rates of vasospasms, hydrocephalus and intraprocedural rupture. The mortality rate was 6.52%, with a mean follow-up duration of 20.77 months. This review reveals that PCAAs predominantly affect females, with an average patient age of 49.93 years. Aneurysms averaged 6.34 mm and often caused SAH. Endovascular treatments were more common but had higher complication rates than microsurgical methods, which also carried risks. The mortality rate was 6.52%.

Traumatic pseudoaneurysm resulting from avulsion of the falcine branch of an azygos anterior cerebral artery: a case report

Traumatic anterior cerebral artery (ACA) aneurysms are extremely rare. Traumatic anterior ACA aneurysms are thought to develop when the ACA at the pericallosal segment travel adjacent to immobile falx cerebri. As the majority of aneurysms are pseudoaneurysms, direct neck clipping is usually not possible, and it is often necessary to carry out direct or endovascular trapping in conjunction with proficient bypass techniques. The authors describe the first reported case of a traumatic ACA pseudoaneurysm resulting from avulsion of the falcine branch of an azygos ACA. In this case, the lacerated aneurysm wall was successfully sutured, without the need for a bypass. Neurosurgeons should be aware that avulsion of the falcine branch arising from the ACA can occur, and that this may cause a traumatic aneurysm on the distal ACA. Furthermore, direct suturing of a lacerated arterial wall should be considered a treatment option for this type of traumatic intracranial aneurysm.

Controversies and Advances in Adult Intracranial Bypass Surgery in 2020

Cerebral revascularization utilizing a variety of bypass techniques can provide either flow augmentation or flow replacement in the treatment of a range of intracranial pathologies, including moyamoya disease, intracranial atherosclerotic disease, and complex aneurysms that are not amenable to endovascular or simple surgical techniques. Though once routine, the publication of high-quality prospective evidence, along with the development of flow-diverting stents, has limited the indications for extracranial-to-intracranial (EC-IC) bypass. Nevertheless, advances in imaging, assessment of cerebral hemodynamics, and surgical technique have changed the risk-benefit calculus for EC-IC bypass. New variations of revascularization surgery involving multiple anastomoses, flow preserving solutions, IC-IC constructs, and posterior circulation bypasses have been pioneered for otherwise difficult to treat pathology including giant aneurysms, dolichoectasia, and medically refractory intracranial atherosclerosis. This review provides a practical update on recent advances in adult intracranial bypass surgery.

In Situ Side-to-Side Pericallosal-Pericallosal Artery and Callosomarginal-Callosomarginal Artery Bypasses for Complex Distal Anterior Cerebral Artery Aneurysms: A Technical Note

BACKGROUND

Despite surgical and endovascular technical improvements over the last decades, the treatment of complex aneurysms of the distal anterior cerebral artery (ACA) is very challenging for both vascular neurosurgeons and interventional neuroradiologists. Furthermore, the interpersonal anatomic variability requires, most of the time, a tailored planning.

OBJECTIVE

To describe a novel technique of bypasses in the territory of ACA to protect the brain territory distal to the aneurysm.

METHODS

A 53-yr-old male with a large complex fusiform aneurysm of the left distal A2 segment of the ACA, involving the origin of the callosomarginal and pericallosal arteries, was judged not suitable for a single procedure (endovascular or neurosurgical). Two side-to-side bypasses were performed in a single surgery to connect the pericallosal and callosomarginal arteries of both sides, distally to the aneurysm. Subsequently, an endovascular embolization of the aneurysm was achieved with coils.

RESULTS

The patency of the microanastomoses, performed in the anterior interhemispheric fissure, was positively evaluated intraoperatively with indocyanine green and fluorescein videoangiography. The aneurysm sac, together with proximal A2 segment, was completely occluded with platinum coils. At the last follow-up, computed tomography angiography confirmed the patency of both bypasses, without any sign of aneurysm recanalization. The patients never complained of any focal neurological deficits or worsening of clinical status.

CONCLUSION

We present an elegant and innovative solution to completely protect the distal ACA territory in cases of complex aneurysm involving the origin of both callosomarginal and pericallosal arteries.

The future of open vascular neurosurgery: perspectives on cavernous malformations, AVMs, and bypasses for complex aneurysms

Despite the erosion of microsurgical case volume because of advances in endovascular and radiosurgical therapies, indications remain for open resection of pathology and highly technical vascular repairs. Treatment risk, efficacy, and durability make open microsurgery a preferred option for cerebral cavernous malformations, arteriovenous malformations (AVMs), and many aneurysms. In this paper, a 21-year experience with 7348 cases was reviewed to identify trends in microsurgical management. Brainstem cavernous malformations (227 cases), once considered inoperable and managed conservatively, are now resected in increasing numbers through elegant skull base approaches and newly defined safe entry zones, demonstrating that microsurgical techniques can be applied in ways that generate entirely new areas of practice. Despite excellent results with microsurgery for low-grade AVMs, brain AVM management (836 cases) is being challenged by endovascular embolization and radiosurgery, as well as by randomized trials that show superior results with medical management. Reviews of ARUBA-eligible AVM patients treated at high-volume centers have demonstrated that open microsurgery with AVM resection is still better than many new techniques and less invasive approaches that are occlusive or obliterative. Although the volume of open aneurysm surgery is declining (4479 cases), complex aneurysms still require open microsurgery, often with bypass techniques. Intracranial arterial reconstructions with reimplantations, reanastomoses, in situ bypasses, and intracranial interpositional bypasses (third-generation bypasses) augment conventional extracranial-intracranial techniques (first- and second-generation bypasses) and generate innovative bypasses in deep locations, such as for anterior inferior cerebellar artery aneurysms. When conventional combinations of anastomoses and suturing techniques are reshuffled, a fourth generation of bypasses results, with eight new types of bypasses. Type 4A bypasses use in situ suturing techniques within the conventional anastomosis, whereas type 4B bypasses maintain the basic construct of reimplantations or reanastomoses but use an unconventional anastomosis. Bypass surgery (605 cases) demonstrates that open microsurgery will continue to evolve. The best neurosurgeons will be needed to tackle the complex lesions that cannot be managed with other modalities. Becoming an open vascular neurosurgeon will be intensely competitive. The microvascular practice of the future will require subspecialization, collaborative team effort, an academic medical center, regional prominence, and a large catchment population, as well as a health system that funnels patients from hospital networks outside the region. Dexterity and meticulous application of microsurgical technique will remain the fundamental skills of the open vascular neurosurgeon.