Subarachnoid haemorrhage due to a dissecting aneurysm of the anterior cerebral artery: a case report

Fusiform aneurysms of anterior cerebral artery: center experience and systematic literature review

Fusiform aneurysms of the anterior cerebral artery (ACA) are uncommon, and the natural history of this entity is poorly characterized. Along with our center experience, we conducted a systematic literature review to help shed light on the clinical course of ACA fusiform aneurysms. We queried our institutional database to identify cases with fusiform aneurysms of ACA. In addition, following the PRISMA algorithm, we identified all reported cases published in the English literature from the inception of PubMed until December 2022. We categorized clinical presentations into three categories: (i) traumatic/iatrogenic, (ii) spontaneous symptomatic ruptured/unruptured, and (iii) spontaneous asymptomatic aneurysms. We utilized descriptive statistics. We identified seven cases from our center along with 235 patients from published literature. Blunt trauma was responsible for the development of 19 aneurysms. Sixty-three percent of these aneurysms tend to rupture within 2 weeks from the initial trauma, and despite treatment, only 74% of these patients had good clinical outcomes. Spontaneous symptomatic presentation occurred in 207 patients and was often associated with previous/concomitant ACA dissection. Subarachnoid hemorrhage from ruptured aneurysms was the most common presentation. Spontaneous symptomatic fusiform aneurysm is rapidly evolving lesions, and treatment is necessary. Three of our own cases were treated with an endovascular flow diverter (pipeline) stenting with good outcomes. Spontaneous asymptomatic aneurysms were reported in nine patients. These lesions are often associated with other vascular abnormalities. Treatment included surgical clipping with good clinical outcomes. Instead, four patients from our center database were managed conservatively with equally good outcomes. Our study demonstrates good clinical outcomes when fusiform aneurysms of ACA, especially when symptomatic, are treated promptly with either reconstructive or deconstructive therapies.

Internal Trapping of a Growing Ruptured Dissecting Aneurysm of the A1 Segment: A Case Report and Literature Review

A 47-year-old man presented with sudden-onset headache and Fisher group 3 subarachnoid hemorrhage. The World Federation of Neurological Surgeons grade was II. Digital subtraction angiography (DSA) only showed a vessel wall irregularity in the A1 segment of the right anterior cerebral artery (ACA), but an obvious bleeding source was not detected. Repeat angiography showed a tiny aneurysmal dilatation in the A1 segment with an intimal flap. The aneurysm enlarged on subsequent angiograms. Dissecting aneurysm was diagnosed, and the patient underwent internal trapping of the A1 segment to prevent rerupture. Postoperative DSA showed complete obliteration of the dissected segment. Magnetic resonance imaging showed a clinically silent cerebral infarction in the territory of the A1 segment perforators. Parent vessel occlusion for a dissected A1 segment can be effective, provided that sufficient collateral blood flow from the contralateral ACA is observed. We recommend endovascular trapping in this setting and hope that fellow clinicians select this approach for this rare pathology.

Indocyanine Green Videoangiography for Surgery of a Ruptured Dissecting Aneurysm in the Precommunicating Anterior Cerebral Artery: A Technical Case Report

BACKGROUND AND IMPORTANCE

Indocyanine green videoangiography (ICG-VA) is an important intraoperative adjunct for saccular aneurysm surgery, but its efficacy in surgery for dissecting aneurysms has rarely been reported. The authors describe the usefulness of preclipping ICG-VA in a rare case of a ruptured dissecting aneurysm located at the precommunicating (A1) segment of the anterior cerebral artery.

CLINICAL PRESENTATION

A 52-year-old woman, with no history of connective tissue diseases or vascular disorders, presented with sudden headache and convulsion. The CT scan showed that the patient had subarachnoid hemorrhage. Angiography showed a dissecting aneurysm in the left A1 segment of the anterior cerebral artery. Thus, the patient underwent trapping of the dissecting aneurysm. ICG-VA was used as an intraoperative adjunct before and after clipping. The preclipping ICG-VA showed the heterogeneously bright dissecting aneurysm and branching arteries even in the presence of hematoma.

CONCLUSION

Preclipping ICG-VA may enhance the advantage of direct surgery for dissecting aneurysm by allowing visualization of the extent of the dissected vascular wall and the related branching arteries. ICG-VA can be an indispensable adjunct to minimize the compromise from the surgical treatment for intracranial dissecting aneurysms.

Aneurysms of the Proximal Segment of the Anterior Cerebral Artery: A New Classification System with Corresponding Therapeutic Options

OBJECTIVE

This study aims to establish a new classification system for proximal anterior cerebral artery (A1) aneurysms and to offer treatment strategies, based on the lessons learned by studying the case reports of 41 patients with A1 aneurysms.

METHODS

A total of 2332 consecutive patients with intracranial aneurysms were treated at a single medical center between June 2005 and May 2015. Forty-one patients with 42 A1 aneurysms were treated by surgical clipping or endovascular coiling. Clinical data, radiographic results, treatments, and patient outcomes were later collected and analyzed.

RESULTS

Of 2332 intracranial aneurysm patients, 1.76% (n = 41) had a total of 42 A1 aneurysms. Twenty-six of these (62%) were proximal A1 segment aneurysms, 9 (21%) were distal A1 segment aneurysms, and 7 (17%) were fusiform A1 aneurysms. A1 aneurysms can be classified into 3 main types. Types IA and IB originate from the posterior wall of the proximal A1 segment. Type IA projects posterior-inferiorly, whereas type IB projects posterior-superiorly. Type IIA originates from the distal trunk of the A1 artery. Type IIB originates from an angle of an abnormal cortical branch or a ring of an A1 arterial fenestration. Type III consists of fusiform or dissecting aneurysms located anywhere along the A1 segment. After studying the range of treatments and outcomes, when treating these complex morphologies, we recommend clipping type I and II A1 aneurysms and embolizing type III A1 aneurysms.

CONCLUSIONS

A1 artery aneurysms are a rare type of aneurysm with unique characteristics. The classification system proposed here accurately summarizes these characteristics to better guide treatment strategies.

Ruptured dissecting aneurysms of the A1 segment of the anterior cerebral artery: three case reports and a review of the literature

Dissecting aneurysms in the anterior cerebral artery (ACA), although rare, can cause ischemic and/or hemorrhagic stroke. Hemorrhagic dissecting aneurysms in the A1 portion of the ACA are often associated with a poor prognosis. We retrospectively investigated three rare cases of hemorrhagic dissecting aneurysms in the A1 portion. Dissecting aneurysms were diagnosed by carotid angiography or computed tomography angiography to visualize morphological changes in the vessel. All patients presented with diffuse subarachnoid hemorrhage. In one case, computed tomography angiography performed at the onset of the subarachnoid hemorrhage revealed fusiform dilatation at the right ACA (A1), which did not appear on a magnetic resonance angiogram obtained 1 year prior to the onset of the subarachnoid hemorrhage. In the other two cases, A1 dissecting aneurysms were diagnosed from a growing aneurysmal bulge revealed at a non-bifurcated site via repeated carotid angiography. Two patients underwent surgical intervention (trapping or clipping), and their outcome was favorable, whereas the third patient died of delayed rebleeding before receiving surgical treatment. Hemorrhagic dissecting aneurysms in the A1 portion cause severe subarachnoid hemorrhage. Surgical treatments that include revascularization are necessary to prevent rebleeding, and direct surgery is recommended, particularly at the A1 portion.

Stent-assisted coil embolization for anterior cerebral artery dissection presented with cerebral infarction

BACKGROUND

Compared to those found in the vertebrobasilar system, intracranial dissection in the anterior circulation is relatively rare, especially in the anterior cerebral artery (ACA). Moreover, only several cases of ACA dissection that underwent endovascular treatment have been reported. Here we present a rare case of gradually developing ACA dissecting aneurysm causing cerebral infarction, successfully treated by stent-assisted coil embolization.

CASE DESCRIPTION

A 36-year-old man was admitted with sudden right hemiparesis. Diffusion-weighted magnetic resonance (MR) imaging showed cerebral infarction in the left ACA territory, and MR angiography showed segmental stenosis at the A2 portion of the left ACA. Three-dimensional digital subtraction angiogram showed segmental dilatation and stenosis at the left A2 portion. We diagnosed ACA dissection causing acute cerebral infarction and treated the patient conservatively. Five months after the onset, the dissecting artery at the left A2 portion formed a gradually dilating aneurysm, suggesting increased risk for aneurysmal rupture. We attempted endovascular treatment entailing coil embolization of an aneurysm while preserving the left A2 with stent assistance. The patient remained neurologically stable 6 months after the procedure.

CONCLUSIONS

Although there are few reported cases of ACA dissection where endovascular treatment was attempted, we consider stent-assisted embolization for gradually developing ACA dissecting aneurysm as an alternative method to prevent bleeding and recurrent infarction.

Surgical clipping of a dissecting aneurysm of the precommunicating segment of the anterior cerebral artery: a case report and review of the literature

Introduction

Dissecting aneurysms of the cerebral arteries are uncommon vascular malformations. Neurosurgical treatment remains critical in the management of patients with such vascular pathologies.

Case presentation

A 20-year-old Caucasian woman presented with a sudden onset of severe headache and loss of consciousness. Computed tomography revealed diffuse subarachnoid hemorrhage, while a computed tomography disclosed a dissecting aneurysm of the precommunicating segment of the right anterior cerebral artery. Cerebral carotid angiography confirmed the presence of the dissecting aneurysm. Due to the peculiar anatomic configuration, endovascular treatment was excluded and surgery was selected. As the left circulation perfused both postcommunicating segments of the anterior cerebral artery and the distal right precommunicating segment was hypoplastic, direct clipping of the right precommunicating segment, close to its origin from the internal carotid artery, was carried out. She recovered after surgery and a late angiography showed the correct positioning of the clip, with regular perfusion of both right and left postcommunicating segments.

Conclusions

The management of dissecting aneurysms of the cerebral arteries is still controversial. With this report we highlight a possible neurosurgical option among therapeutic strategies for these uncommon vascular lesions.

Revascularization for anterior cerebral artery dissecting aneurysms--three case reports

We describe three rare cases of dissecting aneurysms in the anterior cerebral artery (ACA) treated by surgical reconstruction, and reviewed 79 previously reported cases with the ACA dissecting aneurysm. We found that 35 (77.8%) of 45 patients with ischemic event and 15 (40.5%) of 37 patients with hemorrhagic event were treated conservatively, with 11.4% (4/35 cases) and 13.3% (2/15) risk of bleeding and rebleeding, respectively. Furthermore, half of these patients died. The other 32 patients were treated surgically, and their outcome was favorable, especially after surgical reconstruction. Simultaneous treatment of both hemorrhagic and ischemic events is essential. We recommend early treatment with revascularization for patients with ACA dissection that has hemorrhaged and for patients presenting with signs of clinical deterioration with ischemic event.

Sagittal Magnetic Resonance Imaging of Intramural Hematoma From Non-traumatic Dissection of the Anterior Cerebral Artery-Case Report-

A 46-year-old woman presented with non-traumatic anterior cerebral artery dissection manifesting as sudden onset of headache and motor weakness of the right lower limb. Angiography revealed luminal narrowing of the left anterior cerebral artery from the A(3) portion to the distal portion. Sagittal T(1)-weighted magnetic resonance imaging showed hyperintensity due to an intramural hematoma around the flow void signal of the affected anterior cerebral artery. Sagittal magnetic resonance imaging should be performed in suspected cases of anterior cerebral artery dissection to detect the diagnostic finding of intramural hematoma.