Surgical management of complex middle cerebral artery aneurysms

Navigating Complexity: A Comprehensive Approach to Middle Cerebral Artery Aneurysms

Background: The concept of aneurysm "complexity" has undergone significant changes in recent years, with advancements in endovascular treatments. However, surgical clipping remains a relevant option for middle cerebral artery (MCA) aneurysms. Hence, the classical criteria used to define surgically complex MCA aneurysms require updating. Our objective is to review our institutional series, considering the impacts of various complexity features, and provide a treatment strategy algorithm. Methods: We conducted a retrospective review of our institutional experience with "complex MCA" aneurysms and analyzed single aneurysmal-related factors influencing treatment decisions. Results: We identified 14 complex cases, each exhibiting at least two complexity criteria, including fusiform shape (57%), large size (35%), giant size (21%), vessel branching from the sac (50%), intrasaccular thrombi (35%), and previous clipping/coiling (14%). In 92% of cases, the aneurysm had a wide neck, and 28% exhibited tortuosity or stenosis of proximal vessels. Conclusions: The optimal management of complex MCA aneurysms depends on a decision-making algorithm that considers various complexity criteria. In a modern medical setting, this process helps clarify the choice of treatment strategy, which should be tailored to factors such as aneurysm morphology and patient characteristics, including a combination of endovascular and surgical techniques.

[Thrombectomy without temporary clipping for giant partially thrombosed saccular aneurysms]

Cerebral aneurysm thrombosis is one of the factors increasing the risk of microsurgical treatment. Thrombi and calcifications within the aneurysm neck prevent adequate clipping and should be removed before the procedure. At the same time, the process of thrombectomy is difficult and time consuming that increases duration of temporary arterial clipping and risk of cerebral ischemia.

OBJECTIVE

To evaluate the results of thrombectomy without temporary arterial clipping for giant aneurysms of anterior brain circulation.

MATERIAL AND METHODS

Four patients with giant partially thrombosed saccular aneurysms underwent thrombectomy without temporary clipping followed by neck clipping. In all cases, the aneurysm was thrombosed by more than 80-90% of its baseline volume, and aneurysm neck contained parietal thrombi from all sides. Mean duration of thrombectomy from aneurysm opening to bleeding and temporary clipping of the parent artery was 82 minutes, time of temporary clipping was about 12 minutes.

RESULTS

Favorable clinical and radiological postoperative results were obtained in all patients. The authors present a scheme of surgical stages and video presentation involving the main surgical aspects of this procedure.

CONCLUSION

Thrombectomy without temporary clipping of the parent artery is an effective technique for microsurgical treatment of giant partially thrombosed saccular intracranial aneurysms. Since most thrombi are removed without bleeding, duration of temporary blood flow discontinuation in the parent artery is significantly reduced. Therefore, we decrease the risk of cerebral ischemia. This technique can be useful in microsurgical treatment of complex aneurysms of the middle cerebral and internal carotid arteries, as well as other aneurysms.

Giant Middle Cerebral Artery Aneurysms: A 55-Patient Series

BACKGROUND

The treatment of middle cerebral artery (MCA) giant aneurysms (GAs) represents a challenging task.

METHODS

The data for 55 patients treated for MCA GA (≥25 mm) at the N.N. Burdenko NMRCN between 2010 and 2019 were analyZed.

RESULTS

The GAs were located in the M1 segment in 11 (20%) patients, MCA bifurcation in 33 (60%), M2 in 7 (12.7%), and M3 in 4 (7.3%). There were 32 (58.2%) saccular and 23 (41.8%) fusiform GAs. MCA GAs were treated with neck clipping (50.9%), clipping with the artery lumen formation (3.6%), bypass surgeries (34.5%), wrapping (3.6%), and endovascular surgery (7.3%). A worsening of the neurologic state in the perioperative period was observed in 50.9% of patients. The complete closure of GA was achieved in 78.2%. Surgery-related mortality was 1.8%. The long-term outcome was favorable in 76.9% of patients. Surgery-related and disease-related plus treatment failures-related mortality was 9.6%.

CONCLUSIONS

Microsurgical clipping and bypass surgery are the main operative interventions for MCA GA treatment. These operations are technically complex and are followed by a relatively high percentage of complications. The main tasks that require further investigations are the introduction of new precise diagnostic methods for the collateral circulation assessment in the cortical MCA branches, the perfection of the algorithm for the bypass selection, and investigation of the long-term results of the endovascular and combined treatments. It is of major importance to thoroughly observe the patients long-term after the surgery and ensure the possibility for further angiographic studies.