Endovascular treatment of distal middle cerebral artery aneurysms: Report of eight cases and literature review

Pipeline embolization of MCA aneurysms in the M2-M4 segment: Dual center study and meta-analysis

OBJECTIVE

Flow diversion of distal MCA aneurysms in the M2-M4 segments with Pipeline embolization device is promising, but further study is needed. Here, we seek to quantify the safety and efficacy of Pipeline embolization in the M2-M4 region in a dual-center cohort and comprehensive meta-analysis.

METHODS

Clinical and angiographic data of eligible patients was obtained from participating centers. A systematic review was performed with searches of Pubmed, Scopus, Embase, and the Cochrane Library for articles from inception to May 2021. 86 studies were identified in systematic review. Of these, 7 studies with 46 aneurysms met the inclusion criteria and were aggregated with 8 aneurysms from our dual-center cohort for analysis.

RESULTS

In our dual-center cohort, complete occlusion was observed in 88% (7/8) of aneurysms, and no patients experienced hemorrhagic or thromboembolic complications. Clinical outcomes were reported for 100% (54/54) of aneurysms included in meta-analysis and angiographic follow-up was available for 91% (49/54). The overall rate of complete aneurysm occlusion was 80% (95% CI, 69-91%), and the overall rate of clinical complication was 9% (95% CI, 2-16%).

CONCLUSION

Pipeline embolization of cerebral aneurysms of the M2-M4 segments of the MCA was reasonably effective and safe in a small group of selected patients, but further study is needed to validate these preliminary results.

Massive intracerebral hemorrhages due to peripheral middle cerebral artery aneurysm rupture: A case report with a surgical video

Background

Saccular aneurysm in the distal segment of the middle cerebral artery (DMCA) occurs very rarely and often represents with a rupture. We report a successful surgical case of a DMCA aneurysm rupture with large cerebral and subarachnoid hemorrhage.

Case Description

A 44-year-old female presented a sudden onset headache and coma (the Glasgow Coma Scale was 3). Head computed tomography (CT) revealed a subarachnoid hemorrhage around the right Sylvian fissure and large intracranial hematoma in the right parietal lobe. The CT angiography showed a saccular aneurysm in the peripheral cortical segment of the right angular branch of the right DMCA. We decided to perform a right craniotomy to evacuate hematoma and interrupt the aneurysm. Just after the dural incision, the aneurysm ruptured again. We applied a temporary clip on the artery proximal to the aneurysm before excising it.

Conclusion

Aneurysm in DMCA can be treated safely with surgical excision and risk of sudden recurrent hemorrhage needs to be anticipated.

Stent-Assisted Coiling of a Sidewall Aneurysm of the Distal Middle Cerebral Artery: 2-Dimensional Operative Video

Sidewall aneurysm treatment often requires complex management strategies. These can include advanced clipping techniques or stent-assisted coiling techniques. Endovascular coiling alone has been associated with high recurrence rates and is often not feasible.1-4 Flow-diversion embolization has recently become a standard of care for many aneurysms, demonstrating high occlusion rates.4,5 However, the third generation of coil-assist stents can be delivered with 0.0165" microcatheters, being an ideal adjunct to manage this group of aneurysms in more distal locations. In this video, a 16-yr-old teenager with Parry-Romberg syndrome and congenital adrenal hyperplasia had an incidental finding of a 6.5-mm sidewall aneurysm arising off the angular branch of the left middle cerebral artery, found during the work-up of complex partial seizures. The patient consented to the procedure. Due to his young age and aneurysm size, a decision was made to treat the aneurysm through an endovascular approach. Under general anesthesia, a transfemoral approach was carried out using a 6-French short sheath. A 6-French guiding catheter was left in the distal cervical left internal carotid artery; a 0.0165" microcatheter was used to first deploy a 3.0 × 15 mm Neuroform Atlas stent, completely covering the length of the aneurysm. Then, the stent was traversed with the microcatheter to coil the aneurysm. Follow-up cerebral angiogram confirmed complete occlusion of the aneurysm.

Erratum to Evaluating the safety and efficacy of various endovascular approaches for the treatment of infectious intracranial aneurysms: a systematic review. World Neurosurgery. Volume 144, December 2020, Pages 293-298.e15

OBJECTIVE

A review of endovascular cerebral mycotic aneurysm treatment with Onyx liquid embolic, N-butyl-2-cyanoacrylate (NBCA), or coil embolization has not been reported. The authors conduct a systematic review on endovascular treatment methods of mycotic aneurysms.

METHODS

A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986 and 2020. All studies assessing outcomes related to endovascular Onyx embolization, NBCA embolization, or coiling were included.

RESULTS

A total of 74 studies were ultimately selected, including 180 (67% male) patients comprising 243 aneurysms treated endovascularly. The mean age was 38.2 ± 17.6 years, and the most common symptom on presentation was headache (31%). Most aneurysms were located on the middle cerebral artery (52.5%), and over half presented with rupture (53.8%). Coiling was the most commonly employed technique (50.4%), and obliteration rates were comparable across coiling, NBCA, and Onyx (99.1%, 100%, 100%, respectively). Complication rates were also comparable (4.3% vs. 15.2% vs. 8.1%).

CONCLUSION

Embolization for infectious intracranial aneurysm appears to be an effective treatment option for mycotic aneurysms. Embolization rates were comparable between coiling, NBCA, and Onyx embolization. Noninferiority among these modalities cannot be demonstrated given the retrospective nature of this review, evolution of endovascular techniques over the years, and changes in treatment paradigms in the last 2 decades. Ideally, further prospective research will be needed to find which treatment method offers the lowest complication rates and the best outcomes for patients with mycotic aneurysms.

Microsurgical Management of the Middle Cerebral Artery Bifurcation Aneurysms: An Anatomic Feasibility Study

BACKGROUND

The proper head positioning decreases the surgical complications by enabling a better surgical maneuverability. Middle cerebral artery (MCA) bifurcation aneurysms have been classified by Dashti et al. [Surg Neurol. 2007 May;67(5):441-56] as the intertruncal, inferior, lateral, insular, and complex types based on dome projection. Our aim was to identify the optimum head positions and to explain the anatomic variables, which may affect the surgical strategy of MCA bifurcation aneurysms.

METHODS

The lateral supraorbital approach bilaterally was performed in the 4 cadaveric heads. All steps of the dissection were recorded using digital camera.

RESULTS

The distal Sylvian fissure (SF) dissection may be preferred for insular type and the proximal SF dissection may be preferred for all other types. Fifteen degrees head rotation was found as the most suitable position for the intertruncal, lateral type and subtype of complex aneurysms related with superior trunk. Thirty degrees head rotation was found the most suitable position for the inferior type, insular type, and subtype of complex aneurysms related with inferior trunk.

CONCLUSIONS

The head positioning in middle cerebral bifurcation aneurysms surgery is a critical step. It should be tailored according to the projection and its relationship with the parent vessels of the middle cerebral bifurcation.

ENDOVASCULAR MANAGEMENT OF INTRACRANIAL ANEURYSMS ON DISTAL ARTERIAL BRANCHES: ILLUSTRATIVE CASE SERIES AND LITERATURE RETROSPECTION

Intracranial aneurysms located on distal arterial branches are sporadic and scarce. They account for 2%-7% of the middle cerebral artery and 0.7%-2.3% of the posterior cerebral artery aneurysms, where they mainly arise distally from the P2-related sites. Such aneurysms usually remain asymptomatic prior to rupture, making their diagnosis and management really demanding. Endovascular treatment comprising of different neurointerventional techniques is becoming the most operational up-to-date routine to approach distal cerebral branch aneurysms. In this single-institution case series, endovascular selective coiling and/or parent vessel occlusion resulted in successful and total aneurysmal exclusion from cerebral circulation, which brought good recovery. Hereby, we present an illustrative case series of distal arterial branch intracranial aneurysms, discussing their possible etiology and various endovascular management modalities. We also provide a literature retrospection concerned with this rare entity. In conclusion, due to their predisposition for rupture, distal branch intracranial aneurysms should be treated early and aggressively. We do believe that endovascular selective coil occlusion is the management method of choice, while parent vessel occlusion (with liquid embolics) is optimal when aneurysmal coiling cannot be achieved, or when distal cortical territory is well vascularized by strong collateral cerebral circulation.

Distal middle cerebral artery dissection with concurrent completely thrombosed aneurysm manifesting as cerebral ischemia. A case report and review of the literature

We report the case of a 70-year-old woman who presented with an acute ischemic stroke involving the left frontal operculum secondary to an M2 dissection and a concomitant completely thrombosed aneurysm of the left distal middle cerebral artery. Initial imaging work-up was inconclusive due to the lack of typical radiographic features and only repeated imaging studies pointed towards the presence of an arterial dissection combined with a completely thrombosed aneurysm. The aneurysm was partially clipped and wrapped with excellent clinical result at 1-year follow-up. The clinical, imaging and therapeutic challenges of this rare entity are discussed.

Evaluating the Safety and Efficacy of Various Endovascular Approaches for Treatment of Infectious Intracranial Aneurysms: A Systematic Review

OBJECTIVE

A review of endovascular cerebral mycotic aneurysm treatment with Onyx liquid embolic, N-butyl-2-cyanoacrylate (NBCA), or coil embolization has not been reported. The authors conduct a systematic review on endovascular treatment methods of mycotic aneurysms.

METHODS

A systematic literature review was performed using the PubMed and MEDLINE databases for studies published between 1986 and 2020. All studies assessing outcomes related to endovascular Onyx embolization, NBCA embolization, or coiling were included.

RESULTS

A total of 73 studies were ultimately selected including 180 (67% male) patients comprising 243 aneurysms treated endovascularly. The mean age was 38.2 ± 17.6 years, and the most common symptom on presentation was headache (31%). Most aneurysms were located on the middle cerebral artery (52.5%), and over half presented with rupture (53.8%). Coiling was the most commonly employed technique (50.4%), and obliteration rates were comparable across coiling, NBCA, and Onyx (99.1%, 100%, 100%, respectively). Complication rates were also comparable (4.3% vs. 15.2% vs. 8.1%).

CONCLUSIONS

Embolization for infectious intracranial aneurysm appears to be an effective treatment option for mycotic aneurysms. Embolization rates were comparable among coiling, NBCA, and Onyx embolization. Noninferiority among these modalities cannot be demonstrated given the retrospective nature of this review, evolution of endovascular techniques over the years, and changes in treatment paradigms in the past 2 decades. Ideally, further prospective research will be necessary to find which treatment method offers the lowest complication rates and the best outcomes for patients with mycotic aneurysms.

De novo distal middle cerebral artery aneurysm post-excision of intracerebral arteriovenous malformation in an 8-year old

Cerebral arteriovenous malformations (AVMs) are frequently associated with concurrent aneurysms. These aneurysms are commonly haemodynamically related to the AVM and can be classified into extranidal or intranidal in reference to the AVM nidus. An aneurysm arising from an artery that does not angiographically contribute to the blood flow to the AVM is uncommon. A distal middle cerebral artery (dMCA) aneurysm itself is also a rare presentation, especially in paediatric population. We present a rare case of dMCA aneurysm that was noted after successful surgical management of a ruptured AVM in an 8-year-old child and its management. BACKGROUND: About 10-30% of patients with cerebral arteriovenous malformation (AVM) have an associated artery aneurysm. The majority of these aneurysms are flow-related to the malformation. These aneurysms can be classified into extranidal or intranidal in reference to the AVM nidus Rammos et al Am J Neuroradiol 37:1966-1971, [1]. An aneurysm arising from a different artery that does not angiographically contribute to the blood flow associated with the AVM is less common and would generally be regarded as unrelated to the AVM. Distal cerebral artery aneurysm itself is also a rare presentation, comprising of 1-7% of all middle cerebral artery aneurysm. In children, mycotic infection and dissection are the two most common causes for aneurysm in this location. Unlike in adults, berry aneurysms are uncommon in children. We describe a young patient who was found to have distal middle cerebral artery (dMCA) aneurysm in follow-up DSA (Digital Subtraction Angiogram) after the initial successful surgical treatment for a cerebral frontal AVM. In this particular case, endovascular repair is thought to be the best strategy to treat the aneurysm. However, there still remains a lack of consensus of the best management strategy (surgery or endovascular) in treating flow-related aneurysms in general. This is usually based on an individual case scenario and the treatment is tailored depending on various factors including the expertise of the treating team.

Onyx Embolization of Distal Middle Cerebral Artery Aneurysm in a Patient with Nontraumatic Subdural Hematoma

Distal cortical middle cerebral artery (MCA) aneurysm is a rare entity. Despite the challenging procedure, the role of endovascular treatment is emerging due to its safety and efficacy in obliterating the microaneurysm. We report a 25-year-old male, who presented with a history of dizziness and headache for almost 2 weeks. Computed tomography scan showed a right front parietal subdural hematoma (SDH). We could not identify any underlying defining etiology of SDH neither head injury nor coagulopathy disorder. Therefore, diagnostic cerebral angiogram was performed, which showed a microaneurysm in the distal right MCA cortical branch. Hence, complete obliteration of this microaneurysm was performed using Onyx for endovascular embolization. Therefore, this case report demonstrates the efficacy of this modality in the treatment of microaneurysms with SDH.

The Surgical Treatment of a Large Cortical Atherosclerotic Middle Cerebral Artery Aneurysm Presenting With Parietal Lobe Infarction

Distal MCA aneurysms are rarely seen in daily neurosurgical practice and they are, more commonly associated with infectious processes. Here, the authors present a 65-year-old, patient who had an atherosclerotic M4 segment located aneurysm. It was confirmed, that the aneurysm was not related with any infectious process. The patient had, presented clinically by a parietal infarction and she had been successfully operated. The neuronavigation system for this particular case aided us for a precise localization of the aneurysm and gave a chance for a smaller craniotomy.

Usefulness of Intraoperative Imaging in a Patient with a Ruptured Aneurysm of the M4 Segment of the Middle Cerebral Artery

BACKGROUND

Treating cerebral aneurysms in the M4 segment of the middle cerebral artery (MCA) is challenging because they are small and are buried in the brain parenchyma.

CASE DESCRIPTION

A right-handed Asian woman in her 80s was referred to our hospital with a chief complaint of altered level of consciousness. On admission, her consciousness level on the Glasgow Coma Scale was 7 (E1V1M5), and a computed tomography (CT) scan showed subarachnoid hemorrhage with intracerebral hematoma in the left temporal lobe. Subsequent 3-dimensional CT angiography showed an aneurysm in the M4 segment of the left MCA. The aneurysm of the patient was clipped safely and effectively because of the navigation system in combination with intraoperative angiography. The navigation system was especially useful for estimating the proximal part of the parent artery at the brain surface, whereas intraoperative angiography was especially useful for confirming that the proximal portion of the parent artery identified by the navigation system was correct.

CONCLUSIONS

We emphasize the importance of choosing the modality of intraoperative imaging according to each characteristic when treating M4 segment aneurysms.

Endovascular Treatment of Middle Cerebral Artery Dissecting Aneurysms: A 7-Year Single-Center Study

OBJECTIVE

To evaluate safety and efficacy of endovascular treatment of middle cerebral artery dissecting aneurysms (MCADAs).

METHODS

Between July 2009 and April 2016, 14 patients with MCADAs received endovascular treatment. MCADAs were identified by their unique radiographic features on cerebral angiography. Baseline characteristics, angiographic features, and angiographic and clinical outcomes were analyzed retrospectively.

RESULTS

All 14 MCADAs (including 6 ruptured and 8 unruptured) were successfully treated with the endovascular approach. Stent-assisted coiling was used in 12 cases, coil alone in 1 case, and parent vessel occlusion in 1 case. Angiographic follow-up data were available for all patients at 6 months after treatment. Of 14 MCADAs, 10 were completely occluded, and 4 were improved (near occlusion). All parent arteries and covered perforators remained patent in the non-parent vessel occlusion group. No ischemic strokes or other complications were observed at 1-year clinical follow-up.

CONCLUSIONS

Our data suggest that endovascular treatment of MCADAs appears to be safe and effective. The choice of treatment method needs to be individualized. Larger studies are required to evaluate these promising results.

Cortical aneurysms of the middle cerebral artery: A review of the literature

Background:

Middle cerebral artery (MCA) aneurysms constitute from 18–40% of all intracranial aneurysms. They are mainly found in the proximal and bifurcation tracts and only in the 1.1-1.7% of cases they are located in the distal segment. The authors report a case of a ruptured saccular cortical MCA aneurysm with unknown etiology.

Case Description:

A 53-year-old female was admitted with a sudden severe headache, nausea, vomiting, and a slight left hemiparesis. The computed tomography (CT) scan showed subarachnoid hemorrhage (SAH) in the left sylvian fissure and intracerebral hemorrhage (ICH) in the left posterior parietal area. The CT angiography (CTA) reconstructed with 3D imaging showed a small saccular aneurysm in the M4 segment in proximity of the angular area. A left parieto-temporal craniotomy was performed, the aneurysm was clipped and the ICH evacuated. The motor deficit was progressively recovered. At 3-month follow-up examination, the patient was asymptomatic and feeling well.

Conclusions:

In our opinion, surgery is the best choice for the treatment of ruptured M4 aneurysms with ICH, because it allows to evacuate the hematoma and to exclude the aneurysm from the intracranial circulation. In addition, we suggest both the use of the neuronavigation technique and of the indocyanine green videoangiography (ICGV) for the aneurismal surgery.