Intracranial Serpentine Aneurysms: Spontaneous Changes of Angiographic Filling Pattern

Comprehensive Evaluation of Serpentine Aneurysms: a Systematic Review and Meta-analysis with a Subanalysis for Treatment Approaches

PURPOSE

This systematic review and meta-analysis aimed to systematically evaluate and enhance the understanding of optimal management strategies for serpentine aneurysms.

METHODS

A systematic search was conducted in Medline, Scopus, and Cochrane databases up to July 8, 2024, using relevant keywords. Studies included were case series, prospective or retrospective cohorts, or randomized controlled trials with data on clinical and angiographic outcomes of intracranial serpentine aneurysms. Data extraction and quality assessment were performed independently by two authors. Statistical analysis was conducted using R, with pooled estimates under a random-effects model.

RESULTS

Ten studies comprising 70 patients with 71 serpentine aneurysms were included. The majority (92.9%) were giant aneurysms. The overall rate of procedure-related complications was 33%, morbidity was 13%, and mortality was 13%. Good neurological outcomes were achieved in 76% of cases. For unruptured aneurysms, the complication rate was 34%, while no complications were observed in ruptured aneurysms. Comparative analysis between ruptured and unruptured aneurysms showed no significant differences in outcomes or complications. The technical success rate was 91%. Reconstructive methods showed a slightly higher rate of good neurological outcomes (77%) compared to deconstructive methods (70%), though complication rates were similar.

CONCLUSION

Both reconstructive and deconstructive endovascular treatments for serpentine aneurysms are effective, with high rates of good neurological outcomes and acceptable complication rates.

[Pathological tortuosity of intracranial arteries (pure arterial malformation) - diagnosis and management tactics]

BACKGROUND

Tortuosity of intracranial arteries is rare and usually mistaken for arteriovenous malformations. In the world literature, the term «pure arterial malformations» is used to refer to this disease.

OBJECTIVE

To summarize the experience of the Burdenko Neurosurgery Center on diagnosis of intracranial artery tortuosity, management and treatment of these patients, as well as to review appropriate literature data.

MATERIAL AND METHODS

Tortuosity of intracranial arteries was detected in 11 patients (8 women and 3 men) aged 7-48 years who underwent outpatient or inpatient examination and treatment at the Burdenko Neurosurgery Center between 2009 and 2022. We analyzed angiographic, clinical and follow-up data of these patients, as well as appropriate literature data.

RESULTS

According to angiography data, all patients had moderate dilatation, elongation and tortuosity of intracranial arteries without signs of arteriovenous shunting. The most common finding was tortuosity of several segments of internal carotid artery (5 cases). Lesion of PCA, PComA, MCA and ACA was less common. In 7 cases, the walls of the deformed vessels had calcified zones. In two cases, there were saccular aneurysms in the walls of the tortuous vessels. In one case, tortuosity was combined with kinking of the left subclavian artery, in another one - tortuosity of C1 segment of the right ICA. No patient had specific clinical manifestations. The follow-up period was 1-10 years in 7 patients. There were no changes in structure of tortuosity or appearance of new aneurysms.

CONCLUSION

Tortuosity of intracranial arteries is an extremely rare disease with the highest incidence in young women. This abnormality has no specific clinical manifestations and does not require surgical or conservative treatment. Tortuosity of intracranial arteries should be differentiated from arterial dolichoectasia, fusiform aneurysms and AVMs.

Endovascular treatment of a ruptured pure arterial malformation and associated dysplastic middle cerebral artery dissecting aneurysm: illustrative case

BACKGROUND

Pure arterial malformations are characterized as unique cerebrovascular lesions with a dilated, coil-like appearance and tortuous arteries without early venous drainage. Historically, these lesions have been described as incidental findings with a benign natural history. However, pure arterial malformations can rarely demonstrate radiographic progression and develop associated focal aneurysms with an unclear risk of rupture. Whether radiographic progression of these lesions or the presence of an associated aneurysm warrants treatment remains controversial.

OBSERVATIONS

A 58-year-old male presented with sudden-onset left hemiparesis. Computed tomography revealed a large, acute, right frontotemporoparietal intraparenchymal hemorrhage with underlying irregular curvilinear calcifications. Diagnostic cerebral angiography revealed a dysplastic right middle cerebral artery dissecting aneurysm along the M2 segment associated with a pure arterial malformation, which was treated with endovascular flow diversion in a delayed fashion.

LESSONS

Pure arterial malformations with associated focal aneurysms may not exhibit a benign natural history as once thought. Intervention should be considered for ruptured pure arterial malformations to mitigate the risk of rerupture. Asymptomatic patients with a pure arterial malformation with an associated aneurysm should at least be followed closely with interval radiographic imaging to evaluate for malformation progression or changes in aneurysmal morphology.

Flow diversion treatment for giant intracranial serpentine aneurysms

Background

Giant serpentine aneurysms (GSAs) are among the most complex and challenging type of intracranial aneurysms. Surgical clipping, bypass, or endovascular parent artery occlusion has been the main treatment of GSAs in the past. However, studies on flow diversion (FD) are limited. Therefore, we reported our experience with patients with GSAs treated with FD.

Methods

Patients with GSAs treated with FD from 2012 to 2020 in our single center were retrospectively reviewed. Angiographic outcomes were graded according to the O’Kelly–Marotta scale as complete occlusion (D), trace filling (C), entry remnant (B), or aneurysm filling (A). Clinical outcomes were assessed using the modified Rankin scale (mRS) score. We also collected the patients’ treatment details and perioperative complications.

Results

Thirteen patients with 14 aneurysms were included, including three in the anterior circulation and 11 in the posterior circulation. Grades B–D were found in 72.7% (8/11) of the GSAs. Good prognosis (mRS score, 0–2) was found in 66.7% (8/12) and 50.0% (6/12) of the patients at the 6-month and latest follow-up, respectively. Parent artery occlusion was found in three cases of GSAs. Five postoperative complications were observed, including two minor complications and three major complications.

Conclusion

Although reconstructive treatment with FD could be considered as one of the treatment strategies for patients with both anterior and posterior circulation GSAs, however, the risk of complications and parent artery occlusion should be considered.

Endovascular occlusion of giant serpentine aneurysm: A case report and literature review

Giant serpentine aneurysms (GSAs) are a rare subgroup of intracranial aneurysms. Separate inflow and outflow flow due to intraluminal thrombosis is the most distinguishing feature of GSAs. In treating these lesions, surgical clipping and ligation were the main treatments in the past, but bypass for revascularisation and endovascular therapies (EVTs) for deconstructive purposes are more prominent today. A 51-years-old male patient presented with headache and mild right hemiparesis. He had a GSA arising from the left fetal type posterior cerebral artery (fPCA) that was out of follow-up for six years. Radiological images revealed midline shifting and mesencephalon compression. We performed endovascular parent artery coil occlusion. The symptoms of the patient improved at the first-month follow-up. Even if there is a mass effect in GSAs, deconstructive EVT is a safe and feasible method for managing these lesions.

Intracranial Fusiform and Circumferential Aneurysms of the Main Trunk: Therapeutic Dilemmas and Prospects

Intracranial fusiform and circumferential aneurysms (IFCAs), especially those located on the main trunk, are uncommon and difficult to manage. Currently, literature focused on IFCAs on the main trunk of cerebral arteries is lacking. The treatment of IFCAs is still under debate. Therefore, in this review, we further explore the treatment of this complicated entity. In addition, we also present some interesting cases. Based on the literature review and our experience, we found that IFCAs are often located in the vertebrobasilar system and that ruptured or large symptomatic IFCAs are associated with increased mortality and higher rebleeding rates. The treatment strategies for IFCAs can be classified as deconstructive and reconstructive methods via open surgery and/or endovascular treatment (EVT). Currently, EVT is a popular method and the main therapeutic choice. In particular, flow diversion has revolutionized the treatment of IFCAs. Parent artery occlusion (PAO) with or without revascularization may still be considered a suitable choice. Complex IFCAs that cannot be resolved by EVT can also be treated via open surgery with or without extracranial–intracranial bypass. Targeted embolization for the weak points of IFCAs is a temporary or palliative choice that is rarely used. In summary, despite complications, both surgical treatment and EVT are effective options for appropriately selected cases. Due to the development of endovascular implants, EVT will have better prospects in the future.

Striate Artery Infarct After Bilateral Carotid Artery Ligation (BCAL) in a Dog: A Multimodal MRI Study

Bilateral carotid artery ligation has been reported as a lifesaving procedure to control severe hemorrhage. However, reports are sparse and little information is available regarding the potential risks associated with this procedure. We report an ischemic brain infarct as a complication after vascular surgery. A 3-year old, male intact border collie was presented for acute onset of forebrain signs 5 days after bilateral carotid artery ligation. Multimodal brain MRI including morphologic sequences, MR angiography, diffusion- and perfusion-weighted images were performed. MRI revealed a well-defined intra-axial lesion of the left caudate nucleus, with increased T2 and decreased T1 signal intensity and moderate heterogeneous peripheral contrast enhancement. The cerebral blood flow was reduced relative to the contralateral caudate nucleus. Images were consistent with a subacute lacunar ischemic infarct of the left striate artery. Additionally, multiple arterio-arterial anastomosis arising from the vertebral arteries were visible in the angiography sequences. Ischemic infarct due to thromboembolism should be considered as a possible complication associated with bilateral carotid artery ligation. Collateral blood supply can develop as early as 5 days after surgery.

Giant serpentine aneurysm of the internal cerebral artery and mandibular aneurysm: a case report

BACKGROUND

Giant serpentine aneurysms (GSA) originate from saccular or spindle aneurysm, dissimilar from dissected aneurysm, that are defined as partially thrombosed giant aneurysms with tortuous internal vascular channel. The clinical and neuroradiologic characteristics are clarified and the mechanism of formation and the efficacy of double stent implantation in GSA are discussed.

CASE PRESENTATION

An 18-year-old man presented himself with a GSA arising from the internal cerebral artery (ICA). In addition, a mandibular aneurysm (MA) arose from the external cerebral artery (ECA). Success was achieved in treating GSA through endovascular treatment with double stents implanted in the parent artery, which were LEO stent and Tubridge flow diverter. After 1 year of follow-up, three-dimensional reconstruction of blood vessels revealed the disappearance of the serpentine access of GSA, which was found to be replaced with a roughly normal vascular structure.

CONCLUSIONS

Double stent implantation has provided a feasible treatment option for giant serpentine internal carotid aneurysms and eliminated the possibility of causing collateral circulation occlusion. Therefore, it represents a simple and suitable treatment method for anatomical structure and operation.

Natural history and clinical outcomes in patients with complex intracranial aneurysms: a review of 115 bypass cases and 22 nonsurgical cases

The purpose of this study was to evaluate the natural history of patients with these heterogeneous aneurysms to provide guidance for their treatment. This retrospective analysis was performed at a single institution and included 137 patients with complex intracranial aneurysms who underwent a natural history evaluation. Among the 115 patients who underwent bypass surgery, stroke (n = 39, 33.9%) was the most common clinical symptom followed by progressively severe headaches (n = 25, 21.7%). Of the 104 patients with follow-up information, 87 (83.7%) returned to a normal life within a mean follow-up of 4.17 ± 2.09 years. Ten deaths (9.6%) occurred after a mean of 1.3 ± 0.9 years. Among the 22 patients who selected nonsurgical treatment, mass effect (n = 9, 40.9%) was the most common clinical presentation, and 14 deaths (63.6%) occurred after a mean of 3.3 ± 2.5 years. The modified Rankin scale (mRS) scores of 5 survivors (5/22, 22.7%) progressed from 0-2 at initial presentation to 3-4. Bypass surgical treatment for these aneurysms appears to be effective and can achieve good clinical outcomes without additional limitations related to individual aneurysms despite the impact of recent endovascular techniques on vascular surgery.

Giant Serpentine Distal Anterior Cerebral Artery Aneurysm Treated with In Situ Side-to-Side A3-A3 Anastomosis and Aneurysm Resection

BACKGROUND

Giant serpentine aneurysms that occur in the distal anterior cerebral artery are extremely rare and challenging to manage because of their complex structure. In this case, we show an aneurysm resection performed after in situ side-to-side A3-A3 bypass to treat a giant serpentine distal anterior cerebral artery aneurysm.

CASE DESCRIPTION

Here, we present the case of a 55-year-old man with a giant distal anterior cerebral artery serpentine aneurysm who presented with severe headache and progressive unconsciousness. Computed tomography and cerebral angiography revealed a giant serpentine aneurysm in the right A2 segment. Both the right pericallosal and callosal marginal arteries branched from the outflow tract. To relieve the mass effect and preserve distal blood flow, an in situ side-to-side A3-A3 anastomosis and a partial aneurysm resection were performed sequentially. Postoperative cerebral angiography revealed no aneurysm blood filling and good perfusion in both anterior cerebral artery territories.

CONCLUSIONS

Anterior cerebral artery giant serpentine aneurysms are rare and usually present with headache and mass effect. Aneurysm resection and distal flow protection are issues that we must consider. The sequential procedure of anastomosis and aneurysm resection is a feasible and safe option.

Progressive Pure Arterial Malformations of the Anterior Cerebral Artery

BACKGROUND

Pure arterial malformations (PAMs) are rare intracranial vascular anomalies. As recently reported, PAMs have a benign natural history and can be treated conservatively. However, their etiology, natural history, and treatment have not yet been fully elucidated.

METHODS

We present a rare case of the progression of a PAM involving the anterior cerebral artery. Magnetic resonance imaging showed a mass located in the suprasellar region associated with obstructive hydrocephalus. Digital subtraction angiography showed evolution of the arterial anomaly with progression compared with the studies 3 years earlier. Surgical trapping of the parent artery with electrophysiological monitoring was performed. Combined with previous data, the clinical features and therapeutic strategies for this unusual entity are discussed.

RESULTS

The patient recovered uneventfully after surgery. Postoperative digital subtraction angiography confirmed complete obliteration of the lesion. Axial computed tomography also showed shrinkage of the aneurysm, with improvement of the hydrocephalus. Our review of the reported data showed only 4 patients with a definite or probable PAM who had undergone surgery. To the best of our knowledge, the present case represents the first report of changes in the vascular architecture of a PAM during the follow-up period.

CONCLUSION

Whether the aneurysmal component of PAMs merits invasive treatment has remained controversial. The findings from our case raises the possibility of evolution for some patients with PAMs and stresses the importance of scheduled follow-up noninvasive imaging studies to rule out progression of these nosological entities, especially PAMs with an "aneurysm-like" component.