Vertebrobasilar junction fenestration associated with dissecting aneurysm of intracranial vertebral artery

Dissection of the Vertebral Artery Fenestration Limb Presenting with Occlusion After Rupture

BACKGROUND

Dissection of a vertebral artery (VA) fenestration is extremely rare. We herein present the first case of a patient who presented with the dissection of a VA fenestration limb accompanied by occlusion after rupture, who was treated with internal trapping of the dissected limb and the parent artery proximal to the fenestration.

CASE DESCRIPTION

A 55-year-old man presented with sudden headache and altered consciousness. Computed tomography at admission showed subarachnoid hemorrhage. Angiography showed occlusion of the inner limb of the vertebrobasilar junction fenestration, and the occluded ends had a tapered shape, suggesting the occlusion of the dissection of the inner limb after rupture. Angiography immediately before embolization revealed inner limb recanalization with an irregular string sign; thus only the inner limb was embolized. Angiography after embolization showed near-complete suppression of the blood flow in the inner limb; however, a slight antegrade flow through the coil mass was observed in the late phase. The procedure was finished with the expectation of complete occlusion over time with natural heparin reversal. Angiography 8 days after embolization revealed a significant increase in antegrade blood flow through the coil mass within the inner limb. Therefore additional embolization of the parent artery proximal to the fenestration was performed, which achieved complete occlusion.

CONCLUSIONS

The embolization length was limited and the antegrade blood flow through the other limb remained during internal trapping for the dissected VA fenestration limb; therefore careful observation of the blood flow to the dissected segment after embolization is necessary.

Intracranial Arterial Fenestration and Risk of Aneurysm: A Systematic Review and Meta-Analysis

BACKGROUND

Previous studies have been inconsistent regarding risk for intracranial aneurysm related to intracranial arterial fenestration. We conducted a meta-analysis to examine the association between intracranial arterial fenestration and risk of aneurysm.

METHODS

We performed a systematic review of PubMed and Embase through August 2017 for potentially relevant articles. Summary odds ratios with 95% confidence intervals were pooled using a random-effects model.

RESULTS

Of 446 articles found, 7 were selected for meta-analysis. Pooled odds ratios revealed an increased risk of aneurysm owing to fenestration of 1.50 (95% confidence interval, 0.61-3.71; P = 0.38). Subgroup analyses based on the population presenting with various indications suggested that pooled odds ratios indicated a significant increase in risk for aneurysm of 2.43 (95% confidence interval, 1.04-5.69; P = 0.04).

CONCLUSIONS

Our findings indicate that intracranial arterial fenestration may be associated with increased risk for aneurysm formation.

Vertebrobasilar Dissection in a Duplicated Cervical Vertebral Artery: A Possible Pathoetiologic Association?

A thirty-eight-year-old man with extensive spontaneous vertebrobasilar dissection in asso ciation with duplication of the ipsilateral proximal vertebral artery is described. He had no relevant medical history. The development of a spontaneous arterial dissection in a duplicated arterial system suggests a pathoetiologic association that may further expand the list of cerebrovascular pathology occurring with fenestration/duplications.

Treatment of fenestrated vertebrobasilar junction-related aneurysms with endovascular techniques

Fenestrated vertebrobasilar junction-related aneurysms (fVBJ-AN) are uncommon and endovascular management strategies have become the first options for the treatment of these lesions. This clinical study aimed to report our experience in the endovascular management of these lesions and to review the literature. We retrospectively reviewed 10 consecutive patients harboring 12 fVBJ-AN between January 2007 and December 2014. The demographic, angiographic and clinical data were reviewed. Additionally, a literature review was performed. Endovascular management strategies were successfully applied in all 10 patients. Post-procedural angiograms indicated total occlusion in eight (66.7%) aneurysms, a residual neck in one (8.3%) aneurysm, and three residual aneurysms (25%). No procedure-related complications were observed. Follow-up angiograms were obtained in eight patients and revealed nine occluded aneurysms and one improved aneurysm; two patients were lost to angiographic follow-up. Clinical follow-ups were obtained in all patients (until July 2015), and the modified Rankin Scale scores at 69.5months (range 17-101months) of follow-up were 0 in eight patients and 1 in two patients. Endovascular management strategies provided a high occlusion rate and an acceptable complication rate and are thus efficacious in the treatment of fVBJ-AN. Further studies are necessary to validate the utility of these treatments due to the low incidence of fVBJ-AN.

Complex aortic arch anomaly: Right aortic arch with aberrant left subclavian artery, fenestrated proximal right and duplicated proximal left vertebral arteries-CT angiography findings and review of the literature

Congenital aortic arch and vertebral artery anomalies are a relatively rare finding discovered on imaging either incidentally or for evaluation of entities like dysphagia or subclavian steal. Right aortic arch is an uncommon anatomical anomaly that occurs in less than 0.1% of the population, and in half of these cases the left subclavian artery is also aberrant.(1) Unilateral vertebral artery (VA) duplication is rare with an observed prevalence of 0.72% in cadavers.(2) Fenestration of the VA is more common than duplication, with a prevalence of approximately 0.23%-1.95%.(3,4) We describe the case of a 25-year-old female who was found to have a right aortic arch with aberrant left subclavian artery, duplicated left vertebral artery and a fenestrated right vertebral artery on CT angiography performed for evaluation of dysphagia. This combination of findings has not been reported before, to the best of our knowledge. We review the embryologic mechanism for the development of the normal aortic arch, right aortic arch, vertebral artery duplication and vertebral artery fenestration. The incidence of these entities, resultant symptoms and clinical implications are also reviewed. The increased associated incidence of aneurysm formation, dissection, arteriovenous malformations and thromboembolic events with fenestration is also discussed.

Cerebral arterial fenestrations

Arterial fenestrations are an anatomic variant with indeterminate significance. Given the controversy surrounding fenestrations we sought their prevalence within our practice along with their association with other cerebrovascular anomalies. We retrospectively reviewed 10,927 patients undergoing digital subtraction angiography between 1992 and 2011. Dictated reports were searched for the terms "fenestration" or "fenestrated" with images reviewed for relevance, yielding 228 unique cases. A Medline database search from February 1964 to January 2013 generated 304 citations, 127 cases of which were selected for analysis. Cerebral arterial fenestrations were identified in 228 patients (2.1%). At least one aneurysm was noted in 60.5% of patients, with an aneurysm arising from the fenestration in 19.6% of patients. Aneurysmal subarachnoid hemorrhage or non-aneurysmal subarachnoid hemorrhage were present in 60.1% and 15.8%, respectively. For the subset of patients with an aneurysm arising directly from a fenestration relative to those patients with an aneurysm not immediately associated with a fenestration, the prevalence of aneurysmal subarachnoid hemorrhage was 66.7% vs. 58.6% (p = 0.58). Fenestrations were more often within the posterior circulation (73.2%) than the anterior circulation (24.6%), though there was no difference in the prevalence of aneurysms within these groups (61.1% vs. 60.7%, p = 1.0). Cerebral arterial fenestrations are an anatomic variant more often manifesting at the anterior communicating arterial complex and basilar artery and with no definite pathological relationship with aneurysms.

Endovascular management of multiple cerebral aneurysms in acute subarachnoid hemorrhage associated with fenestrated basilar artery. A case report and literature review

Aneurysms arising from the fenestration of the basilar artery are rare. We describe a patient with two aneurysms originating from the fenestration of the basilar artery and the middle cerebral artery. Endovascular treatment with detachable platinum coils was performed, and two aneurysms were cured at the same time. Endovascular treatment of aneurysms associated with fenestrated basilar artery appears to offer advantages over traditional open surgical techniques.

Three-dimensional visualization of vertebrobasilar system aneurysms in a vertigo patient

Cerebral artery fenestration refers to a division in the lumen of an artery leading to two distinct endothelium-lined channels. At the site of turbulent flow, fenestration may predispose to an aneurysm formation. In this study, a 45-year-old woman suffered an acute vertiginous attack after cervical manipulation. The MRI scan demonstrated basilar artery duplication and tortuous left distal vertebral artery impinging on the cisternal segment of the cochleovestibular nerve. Subsequent three-dimensional (3D) reconstruction by MR imaging showed vertebrobasilar artery fenestrations with aneurysms. Unfortunately, subarachnoid hemorrhage occurred 6 days later, and the patient became comatose one year after presentation. In summary, subarachnoid hemorrhage caused by vertebrobasilar system aneurysms is a life-threatening event. Delineating the configuration by 3D-reconstruction of MR images allows more accurate diagnosis and more effective management.

Neuroradiological Analysis of 23 Cases of Basilar Artery Fenestration Based on 2280 Cases of MR Angiographies

SUMMARY

Basilar artery (BA) fenestrations are the most frequently observed variant of the cerebral arteries. We examined the magnetic resonance (MR) angiographic incidence, location, characteristic configuration of BA fenestration and associated vascular disease. From April 2004 to September 2004, a total of 2280 cranial MR angiographies were performed at our institution. Twenty-three BA fenestrations (1.0%) were detected on MRA. There were 13 males and ten females in this group and mean age was 57.6 years old. Three cases of these fenestration group are suffered with atherothrombic infarction in the territory of vertebro-basilar system. Seven of 23 cases (30%) were associated with intracranial aneurysm. Of those four cases, aneurysms were located at anterior circulation. Of those three cases, the aneurysms were associated with BA fenestration. Since saccular aneurysms are reported to arise frequently at BA fenestration, knowledge and recognition of fenestration are useful and important in the interpretation of cerebral MR angiography.

Ruptured fusiform aneurysm of fenestrated A1 segment of the anterior cerebral artery

We present a case report of a 56-year-old woman with a ruptured fusiform aneurysm of a fenestrated A(1) segment of the anterior cerebral artery (ACA). Fenestrated A(1) segments are rare and only a few case reports have been published of a saccular type aneurysm formation. To the best of our knowledge, there have been no documented cases of fusiform aneurysms in these segments.

Aneurisma dissecante de artéria vertebral intracraniana fenestrada submetido ao tratamento endovascular: relato de caso

Aneurismas dissecantes da artéria vertebral em seu segmento intracraniano são lesões pouco comuns, principalmente quando associadas a hemorragia subaracnóidea, sendo também raras as fenestrações da artéria vertebral. Apresentam elevada morbidade e mortalidade, com elevado índice de ressangramento e dificuldade de abordagem cirúrgica. Apresentamos o caso de um homem de 19 anos, o qual foi vitima de agressão física em região occipto-cervical, apresentando hemorragia subaracnóidea e aneurisma dissecante na artéria vertebral direita, a qual era fenestrada, sendo submetido ao tratamento endovascular. Realizamos revisão da literatura sobre o assunto, sendo colocado o tratamento endovascular como uma opção terapêutica para estes casos.

Dissecting aneurysm of the anterior cerebral artery presenting with thrombo-embolic complications. A case report

SUMMARY

A dissecting aneurysm of the anterior cerebral artery is a relatively rare disorder. A patient is presented with mild symptoms due to thromboembolic complications from a dissecting aneurysm of the pericallosal artery. The patient had a good outcome after conservative treatment. A review of the literature is presented.

Spontaneous fusiform middle cerebral artery aneurysms: characteristics and a proposed mechanism of formation

OBJECT

The goal of this study was to identify the origins of spontaneous fusiform middle cerebral artery (MCA) aneurysms.

METHODS

One hundred two cases of spontaneous fusiform MCA aneurysms were reviewed, including 40 from the authors' institutions and 62 identified from the literature. The mean age at symptom onset was 38 years, and the male/female ratio was 1.4:1. At presentation, the MCA lumen was stenosed or occluded in 12 patients, focally dilated in 57, and appeared "serpentine" in 33. Most lesions originated from the M1 or M2 segments, and most (80%) presented with nonhemorrhagic symptoms or were discovered incidentally. The presenting clinical features correlated with morphological findings in the aneurysms, which could be observed to progress from a small focal dilation or vessel narrowing to a serpentine channel. Hemorrhage was the most common presentation in small lesions; the incidence of bleeding progressively diminished with larger lesions. Patients with stenoses or occluded vessels most often presented with ischemic symptoms, and occasionally with hemorrhage. Giant focal dilations or serpentine aneurysms were rarely associated with acute bleeding; clinical presentation was most often prompted by mass effect or thromboembolic stroke.

CONCLUSIONS

Analysis of results after various treatments indicates that for symptomatic lesions, therapies that reverse intraaneurysmal blood flow and augment distal cerebral perfusion are associated with better outcomes than other strategies, including conservative management. Based on the spectrum of clinical, pathological, neuroimaging, and intraoperative findings, dissection is proposed as the underlying cause of these lesions.

Fenestration of the internal carotid artery associated with arterial dissections

An increasing number of cases with fenestration that is frequently associated with aneurysms have been reported, largely in the vertebral and basilar arteries and less commonly in the middle and anterior cerebral arteries by angiography as well as by autopsy. However, the anomaly of the internal carotid artery associated with bilateral arterial dissections is exceedingly rare. This represents the first reported case of fenestration of the internal carotid artery associated with arterial dissections. The embryological basis and clinical significance of this anomalous condition are discussed and treatment for arterial dissection is presented.

Spontaneous occlusion of ruptured vertebral artery dissection at the extradural fenestration associated with extradural origin of the posterior inferior cerebellar artery--case report

A 69-year-old female suffered from sudden onset of severe headache. Computed tomography showed subarachnoid hemorrhage primarily located in the posterior fossa. Initial angiography demonstrated a fenestration of the vertebral artery and an extracranial origin of the posterior inferior cerebellar artery. However, no bleeding points could be clearly detected. The operative findings revealed a massive clot in subarachnoid space, but no bleeding point. Serial angiography demonstrated dissection in one of the limbs of the fenestrated vertebral artery on the 25th day after the onset. On the 100th day, the lesion was spontaneously occluded. The patient is presently doing well at 8 years after surgery.

Late hemorrhage from persistent pseudoaneurysm in vertebral artery dissection presenting with ischemia: case report

BACKGROUND

Vertebral artery dissection lesions tend to resolve spontaneously, but abnormal findings such as aneurysmal-dilatation occasionally persist. However, the clinical features and pathological findings in such cases have never been verified.

CASE DESCRIPTION

A 62-year-old man presented with left cerebellar infarction. Angiography showed the "pearl and string sign" in the left vertebral artery, and he was diagnosed as having left vertebral artery dissection. Repeated angiography showed persistent aneurysmal dilatation with irregular stenosis. Eleven years after the cerebellar infarction, the patient presented with a subarachnoid hemorrhage from an aneurysm of the left vertebral artery, and the lesion was explored via the left suboccipital approach. The vertebral artery was firm, making the placement of a clip impossible, so the lesion was treated by coating of the bleeding point. The patient died of pneumonia and hyperglycemia on postoperative day 15. Postmortem examination revealed an organized intramural hematoma, thickening of the intima, and fibrous degeneration of the media of the vertebral artery, a fusiform, distended thin arterial wall with intimal disruption at the aneurysmal dilatation, and arteriosclerosis of all cerebral arteries.

CONCLUSION

This case indicates that persistent aneurysmal dilatation of a dissection is a pseudoaneurysm prone to rupture, and that healing of the affected vessels might be severely compromised in the presence of pathological conditions such as arteriosclerosis and disturbed intraluminal blood flow in the dissected lesions.

Influence of percussion trauma on expression of intercellular adhesion molecule-1 (ICAM-1) by human cerebral microvascular endothelium

OBJECTIVES

Brain injury is associated with the production of oxygen free radicals (OFR) and the accumulation of polymorphonuclear leukocytes (PMN) at the site of injury, both of which may be involved in the evolution of secondary cerebral injury. Intercellular adhesion molecule-1 (ICAM-1) is responsible for adherence of PMNs. We sought to determine whether percussion trauma altered the expression of ICAM-1 and to determine the effect of OFR scavengers on ICAM-1 expression after percussion trauma.

DESIGN

Prospective controlled laboratory research using passage 2 human cerebral microvascular endothelium (HCME).

MATERIALS AND METHODS

Cell lysates were collected over 24 hours and analyzed for ICAM-1 by enzyme-linked immunosorbent assay (ELISA) after trauma or incubation with tumor necrosis factor (TNF)-alpha. OFR scavengers were added immediately after trauma with or without previous incubation with TNF-alpha.

MEASUREMENTS AND MAIN RESULTS

Sublethal percussion trauma did not alter ICAM-1 expression by HCME. TNF-alpha upregulated ICAM-1 in percussed and nonpercussed cells with maximal ICAM-1 expression at 24 hours (p < 0.01, ANOVA). However, percussion trauma significantly blunted the response of HCME to TNF-alpha. The addition of OFR scavengers after percussion trauma alone had no effect on ICAM-1 expression at 24 hours, but restored the response of percussed HCME to TNF-alpha.

CONCLUSIONS

Percussion trauma alters the response of HCME to cytokine-induced ICAM-1 upregulation, and the normal response is restored by OFR scavengers. This suggests that HCME become dysfunctional after percussion trauma and this dysfunction may be mediated by OFR.