Fenestration of supraclinoid internal carotid artery and associated aneurysm: embryogenesis, recognition, and management

Treatment of an intracranial aneurysm in the setting of fenestration of cranial division of the internal carotid artery: Technical considerations and a literature review

Although rare, cerebral arterial fenestration may present challenges in diagnosis and treatment. Here we present a case of a supraclinoid internal carotid artery (ICA) fenestration adjacent to an ICA aneurysm, successfully treated with balloon-assisted coil embolization. A female in her 50's presented with an acute subarachnoid hemorrhage from a ruptured left ICA-ophthalmic artery (OA) aneurysm. Digital subtraction angiography revealed a focal ICA fenestration distal to the posterior communicating artery (Pcom). The patient underwent successful coil embolization of the aneurysm using the balloon-assisted technique. No immediate hemorrhagic, thromboembolic, or neurological complications were observed. The patient was discharged in good condition after 2 weeks of hospitalization. A comprehensive literature review of 33 cases was subsequently performed to understand the characteristics of this condition. Cases involving the cranial division of the ICA forming the fenestration exhibited caliber differences significantly more frequently (p = 0.02). Embryological insights revealed distinctions between the cranial divisions of the ICA, influencing fenestration morphology and associated aneurysm formation. Endovascular treatment poses the risk of vascular injury, necessitating the identification of this variation and procedural planning.

Endovascular treatment of a supraclinoid internal carotid artery fenestration aneurysm: A case report and literature review

Supraclinoid internal carotid artery (ICA) fenestration aneurysm is rare. Except for open surgery, endovascular treatment (EVT) is considered an alternative for such an aneurysm. However, experience with this procedure is lacking. Therefore, we reported such a case. A 61-year-old woman suffered subarachnoid hemorrhage. Digital subtracted angiography (DSA) showed bilateral middle cerebral artery (MCA) aneurysms and a saccular aneurysm associated with fenestration of the supraclinoid ICA. Two MCA aneurysms were treated with single coiling, and the supraclinoid ICA fenestration aneurysm was coiled under stent assistance. The postoperative recovery was uneventful. At this time, a literature review was performed on the role of EVT in supraclinoid ICA fenestration aneurysms. A total of 13 supraclinoid ICA fenestration aneurysms treated by EVT in 11 cases, including our case, were obtained. After EVT, good outcomes were obtained in all cases. To our knowledge, this is the first study to review the role of EVT for supraclinoid ICA fenestration aneurysms. Our case report and literature review indicated that EVT for such aneurysms may be feasible and act as a therapeutic alternative.

Endovascular treatment of an aneurysm associated with fenestration of the supraclinoid internal carotid artery: Case report and review of the literature

Background

Fenestrations or divisions of the vascular lumen into separate channels appear to be common anatomical variations in patients with intracranial aneurysms. The most frequent sites of occurrence are the anterior communicating artery (ACom), followed by vertebrobasilar and middle cerebral artery (MCA) locations.

Case presentation

A 61-year-old female was brought to the emergency department after experiencing severe headache with abrupt onset, nausea, and vomiting. Clinical examination on arrival showed a drowsy patient (GCS 14), with neck stiffness, but no cranial nerve palsies or other neurological deficits (Hunt-Hess 2). Non-contrast head CT and CT angiography revealed subarachnoid and intraventricular hemorrhage (modified Fisher 4) and two saccular aneurysms, one located on the right supraclinoid ICA with peripheral calcifications, measuring 20 × 12 mm, the second on the left MCA bifurcation, 6 × 4 mm. 3D rotational angiography revealed a right ICA fenestration located between the ophthalmic (OA) and posterior communicating artery (PCom). The proximal part of the fenestration harbored a large saccular aneurysm projecting superiorly with the neck engulfing the origin of the fenestration; due to the favorable neck and geometry of the aneurysm, endovascular coil occlusion was chosen as a treatment option without balloon or stent assistance. The decision was taken to clip the MCA aneurysm.

Conclusion

Supraclinoid ICA fenestrations are rare anatomical variations. Endovascular treatment of supraclinoid ICA fenestration-related aneurysms is feasible and safe, with the notable concern of perforators originating from the limbs.

Supraclinoid internal carotid artery fenestration from which the posterior communicating artery arising with infundibular dilatation at its origin diagnosed by magnetic resonance angiography

A 72-year-old man with vertigo underwent cranial magnetic resonance (MR) imaging and MR angiography using a 3.0-Tesla scanner. MR angiography showed an aneurysm-like lateral protrusion from the left supraclinoid internal carotid artery (ICA) and infundibular dilatation of the left posterior communicating artery at its origin. After creating both partial maximum-intensity-projection images and partial volume-rendering images, a fenestration of the supraclinoid ICA was found. The posterior communicating artery arose from the fenestrated segment, and its origin was dilated triangularly, indicating infundibular dilatation. Cerebral arterial fenestration is not so rare, but it is rarely found at the ICA. The majority of recently reported cases had an associated aneurysm at the proximal end of the fenestration diagnosed using three-dimensional rotational angiography (3DRA). MR angiography is noninvasive and widely used for the screening of cerebral arterial lesions. Even though 3.0-Tesla scanner, special resolution of MR angiography is much lower than that of the 3DRA. For the diagnosis and confirmation of this rare variation, partial maximum-intensity-projection images and/or partial volume-rendering images are useful.

Treatment of Supraophthalmic Internal Carotid Artery Fenestration with an Associated Aneurysm via Flow Diversion: A Case Report

Cerebral artery fenestration with flow-associated aneurysm is rare among cerebrovascular pathologies. Treatment includes open neurosurgery and/or endovascular treatment. We report a case of a 53-year-old woman with an incidentally detected aneurysm during magnetic resonance tomography. As the underlying cause, a digital subtraction angiography revealed a left internal carotid artery fenestration. Elective endovascular treatment via flow diversion was indicated and a pipeline embolization device was implanted. Follow-up examinations presented a completely occluded additional caudal limb and a decreasing aneurysm size. No clinically adverse events occurred within twenty-four-month post-treatment. Therefore, sole flow diversion was a feasible treatment option in this case.

Balloon-Assistance for the Transcirculation Access of a Remodeling Balloon for Coiling of Wide-Necked Aneurysms: Report of Two Cases

Balloons are valuable tools in the armamentarium of a neurointerventionist. In this report, we describe 2 cases in which a balloon aided in the navigation of a second remodeling balloon through difficult vascular anatomy. The first case was a patient with a ruptured proximal posterior inferior cerebellar artery aneurysm and the second case was a patient with a ruptured anterior communicating artery aneurysm. In both cases, the coiling microcatheter and the remodeling balloon catheters were advanced through different vessels. The remodeling balloon reached the target location using a transcirculation approach, and the navigation of the remodeling balloon was aided by utilizing a second balloon. Challenging vascular anatomy is often encountered when performing neuroendovascular procedures. The strategy of using balloon assistance for the transcirculation access of a remodeling balloon can be used successfully in difficult situations to manage complex aneurysms.

Endovascular Management of Complex Fenestration-Associated Aneurysms: A Single-Institution Retrospective Study and Review of Existing Techniques

BACKGROUND

Aneurysms associated with fenestrations of intracranial arteries are exceptionally rare findings. Management strategies for these aneurysms are not well-defined, especially regarding endovascular treatment. We sought to investigate the strategies and feasibility of endovascular treatment approaches for various fenestration-associated intracranial aneurysms.

METHODS

We performed a retrospective chart review of 2000 aneurysms treated endovascularly, identifying 8 aneurysms located at arterial fenestrations. The technical details and procedural outcomes were reviewed to identify common management approaches, technical nuances, and treatment outcomes.

RESULTS

There were 3 (37.5%) aneurysms associated with fenestrations of the basilar artery or vertebrobasilar junction. All 3 were successfully treated with a previously undescribed coil-assisted flow-diversion technique, resulting in complete obliteration. Three (37.5%) aneurysms were associated with fenestrations of the anterior communicating artery. Of those, 2 were successfully treated with stent-assisted coil embolization and 1 with coil embolization alone. One (12.5%) aneurysm was associated with a fenestration of the paraclinoid internal carotid artery and 1 (12.5%) aneurysm found was at the takeoff of the posterior inferior cerebellar artery at a fenestration of the vertebral artery. Both were successfully treated with coil-assisted flow diversion. There were no permanent procedural complications. Major considerations for endovascular management of these aneurysms were the dominance of fenestration trunks, aneurysms arising from the fenestration apex or a fenestration limb, amenability to flow diversion, and anticipation of vascular remodeling.

CONCLUSIONS

Fenestration-associated aneurysms are very rare. We have identified common factors to help guide decision-making for endovascular approaches and demonstrate successful aneurysm treatment using these methods.

Supraclinoid Internal Carotid Artery Fenestration with Associated Aneurysm: Case Report and Literature Review

Fenestration of the supraclinoid internal carotid artery (ICA) is extremely rare and may occasionally be associated with saccular aneurysms; nevertheless, the natural history remains unclear. The authors reviewed the cases of fenestration of the supraclinoid ICA and evaluated the clinical characteristics and angioarchitecture with particular focus on the incidence for aneurysm development and rupture. Previously reported 24 cases and 1 new case from our institute were examined for the presence of aneurysms (including size and presence of bleb) leading to subsequent subarachnoid hemorrhage (SAH). Furthermore, 16 cases with sufficient information were classified into one of the three types according to the developmental condition of fenestration and fusion site: Type A (developed fenestration in which the ICA appears to duplicate [two cases]); Type B (hypoplastic fenestration fused to the ICA at the origin of the posterior communicating artery [Pcom] [six cases]); and Type C (hypoplastic fenestration fused to the Pcom itself or appeared to be a duplicated Pcom [eight cases]). In type A, the two cases had an aneurysm (100%), one of which caused SAH (50%). In type B, all six cases had an aneurysm (100%), and one of five led to SAH (20%) (one case lacked information regarding SAH). In type C, five of the eight cases had an aneurysm (62.5%), with no SAH (0%). The result suggested that the extent of development of fenestration and the location of fusion are related to the incidence of aneurysms and risk for rupture.

Anterior communicating artery complex fenestration combined with tandem aneurysm: a case report and literature review

INTRODUCTION

Clinically, anterior communicating artery complex fenestration combined with fenestration-related aneurysms is rare, and combination of this condition with tandem aneurysms is even rarer.

PATIENT CONCERNS

A case of a 43-year-old man with spontaneous subarachnoid hemorrhage.

DIAGNOSIS

A computed tomography angiography examination revealed a fenestrated anterior communicating artery complex combined with 2 aneurysms. Then, a digital subtraction angiography examination was performed to further determine the diagnosis, which showed a complex anatomical structure of the local tissue. After the aneurysms ruptured, they were partially wrapped by a hematoma and compressed, which increased the difficulty of surgery.

INTERVENTIONS

An endovascular interventional therapy method was chosen, and a simple coil was successfully inserted through the blood vessel into the tandem aneurysms to maintain the integrity of the anatomical structure.

OUTCOMES

The patient recovered well postoperatively. An imaging review after the operation did not show the aneurysms, and the upper and lower branches were patent.

CONCLUSION

Therefore, endovascular treatment is an appropriate choice for arterial fenestration combined with tandem aneurysms, once the aneurysms have ruptured.

An interdisciplinary approach to the treatment of a complex infraclinoidal internal carotid artery aneurysm

We present the case of a 49-year-old woman with sudden onset of severe headaches and a ruptured aneurysm located inside the fenestration of the infraclinoid part of the internal carotid artery in the segments C4 and C5 distal to the origin of the ophthalmic artery. An interdisciplinary approach enabled the successful treatment of the aneurysm by wrapping and stent-assisted coiling. We discuss this rare congenital anomaly of a fenestrated internal carotid artery together with the 12 other cases published worldwide.

Endovascular management of a ruptured aneurysm associated with distal PICA fenestration

Fenestrations are rare but well-known arterial anatomic variations in which a segment of artery divides into two parallel channels that reunite distally. Although fenestrations as such are asymptomatic, they have gained clinical significance because of their association with aneurysms and other intracranial vascular pathologies. Here we present a 35-year-old woman with history of sudden severe occipital headache and vomiting. Imaging revealed a ruptured aneurysm in the distal posterior inferior cerebellar artery arising from one of the limbs of the fenestration. The aneurysm was successfully managed by coiling, and the patient made complete recovery without neurological sequelae.

Fenestration of the supraclinoid segment of the ICA and associated aneurysms: a case report with literature review

The supraclinoid ICA fenestration (SIF) is considered an extremely rare congenital anomaly. However, most of the reported cases of SIF are associated with intracranial aneurysms either ruptured or unruptured. We report the case of a 55-year-old patient with a right SIF and an unruptured, large, wide-necked aneurysm located on the larger limb of the fenestration and a second small aneurysm distal to the SIF. The aneurysms were treated with a Pipeline flow-diverter stent, achieving the complete reconstruction of the anatomy of the carotid siphon. The literature concerning these peculiar anatomic conditions has been reviewed, allowing discussion about treatment of such associated lesions.

Fenestration of the supraclinoid internal carotid artery connecting the neck of the paraclinoid aneurysm and the origin of the posterior communicating artery: A case report

Fenestration of the supraclinoid internal carotid artery is extremely rare and frequently associated with aneurysms at the fenestrated segment or other vascular anomalies. We present a rare case of fenestration of the right supraclinoid internal carotid artery in which a small fenestrated segment arose from the neck portion of the paraclinoid aneurysm and fused with the origin of the posterior communicating artery.

Misdiagnosis of a Patient with Internal Carotid Artery Fenestration: A Case Report and Literature Review

BACKGROUND

Internal carotid artery fenestration is a rare congenital cerebrovascular condition and can be misdiagnosed as carotid artery dissection.

CASE REPORT

A patient was initially misdiagnosed with carotid artery dissection. This initial diagnosis was made using a carotid vascular computed angiography and magnetic resonance angiography. A digital subtraction angiography examination revealed a fenestration in the terminal C1 segment of the right internal carotid artery. Previous literature related to carotid artery fenestration was reviewed and analyzed.

CONCLUSIONS

Fenestration of the carotid artery combined with aneurysm at the external segment of the internal carotid artery or from the starting position of the carotid artery remains rare in elderly patients, can be misdiagnosed as artery dissection.

Fenestration of the supraclinoid internal carotid artery in a patient with a concomitant intracranial arteriovenous malformation

Accurately recognising a supraclinoid internal carotid artery (ICA) fenestration, despite its rare location, is important as it can mimic an intracranial aneurysm, intraluminal thrombus or focal dissection on non-invasive imaging. The overwhelming majority of reported supraclinoid ICA fenestrations are associated with intracranial aneurysms; however, a concomitant arteriovenous malformation (AVM) remote from the fenestration site should also be considered. We present the case of a 26-year-old woman with a Spetzler-Martin grade I right frontal AVM in whom a left supraclinoid ICA fenestration was incidentally discovered during cerebral angiography. She underwent n-N-Butyl Cyanoacrylate glue embolisation of two dominant middle cerebral artery feeders followed by neurosurgical resection. She tolerated procedures well without complications and has remained neurologically intact.

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.

Supraclinoid internal carotid artery fenestration harboring an unruptured aneurysm and another remote ruptured aneurysm: case report and review of the literature

A fenestration of the supraclinoid internal carotid artery (ICA) is a rare congenital condition. We report an aneurysm arising from the proximal end of an ICA fenestration that was treated by endovascular coiling. Three-dimensional rotational angiography of preoperative cerebral angiography provided an understanding of the complex anatomy of the aneurysms associated with the fenestration and may facilitate the clinical decision regarding the treatment option. Endovascular coiling appears to be safe and effective for treating an aneurysm originating from a fenestration on the supraclinoid ICA, which is a difficult lesion to treat using a conventional surgical approach.