De novo distal posterior cerebral artery aneurysm

Endovascular Treatment of Posterior Cerebral Artery Trunk Aneurysm: The Status Quo and Dilemma

The posterior cerebral artery (PCA) is an important artery that can be divided into four segments (P1-4): segments P1-2 are proximal segments, and segments P3-4 are distal segments. Various aneurysms can occur along the PCA trunk. True saccular aneurysms are rare, and most PCA trunk aneurysms are dissecting. Sometimes, the PCA trunk can give rise to flow-related aneurysms in association with high-flow arteriovenous shunt diseases or moyamoya disease and internal carotid artery occlusion. Some PCA trunk aneurysms require treatment, especially ruptured or large/giant aneurysms. Recently, endovascular treatment (EVT) has become the mainstream treatment for PCA trunk aneurysms, and it mainly involves reconstructive or deconstructive techniques. Traditional EVT includes selective coiling with/without stent or balloon assistance and parent artery occlusion (PAO). For proximal aneurysms, the PCA should be preserved. For distal aneurysms, PAO can be performed. However, during EVT, preservation of the PCA must naturally be the prime objective. Recently, flow-diverting stents have been used and are a revolutionary treatment for unruptured dissecting aneurysms of the PCA trunk. Despite the associated complications, EVT remains an effective method for treating PCA trunk aneurysms and can result in a good prognosis.

Pathogenic Factors and Prognosis of De Novo Aneurysms vAfter Aneurysm Clipping

OBJECTIVE

To confirm this hypothesis, this study aimed to explore the pathogenic factors, prognosis, and their relationship in de novo aneurysms and to reach a consensus on their management.

METHODS

First, the clinical data of 5 patients with de novo aneurysms from April 1998 to October 2021 were analyzed retrospectively. Then, the English literature on de novo aneurysms reported in Pubmed from 1985 to 2021 was systematically reviewed, and 18 case reports from 17 articles and 16 case series were identified. Univariate and multivariate analyses and modified Fisher test were used to analyze the relationship between pathogenic factors and prognosis.

RESULTS

Hypertension was noted in 60% of our clinical cases, 50% of the case series identified in the literature review, and 66.7% of the case reports in the literature review. In the case reports identified from our literature review, the proportion of original aneurysms in the anterior circulation was 96.3%. Moreover, in our 5 cases, all original aneurysms occurred in the anterior circulation. The rupture rate of original aneurysms in our 5 cases was 100%, and that of the cases reported in the literature review was 88.9%. Univariate logistic analysis showed that the time interval was related to the prognosis of de novo aneurysms with a P value of 0.048 and an odds ratio of 0.968 (95% confidence interval 0.938-1.000). Modified Fisher exact tests showed that patient age at the occurrence of de novo aneurysm P = 0.029) was related to the prognosis of de novo aneurysms.

CONCLUSIONS

Hypertension, an original aneurysms located in the anterior circulation and rupture represent the pathogenic factors associated with de novo aneurysms. The time interval to de novo aneurysm and patient age at the occurrence of de novo aneurysm are predictive of prognosis. Based on the above information, we can prevent and improve the prognosis of de novo aneurysms.

Endovascular treatment of P3 segment of posterior cerebral artery aneurysm with stent and coils

Posterior cerebral artery (PCA) aneurysms are rare and usually arise from proximal portion of the artery. The distal location is even less frequent, and aneurysms in this location tend to be larger and dissecting. Although they can be treated by direct surgery, recently endovascular procedures have been preferred in some centers. We report a case of large aneurysm of the posterior cerebral artery in a 45-year-old female presenting with headache. An uneventful endovascular treatment was performed with stent and platinum coils achieving total occlusion of the aneurysm, and the patient had good recovery. The findings are compared to earlier reports and literature regarding the issue is discussed.

De Novo Aneurysm: Case Reports and Literature Review

BACKGROUND AND IMPORTANCE:

Formation of cerebral de novo aneurysms (CDNAs) is rare, and the pathogenesis remains obscure. We analyzed factors involved in formation of CDNAs and suggest guidelines for follow-up of patients.

CLINICAL PRESENTATION:

We retrospectively reviewed intracranial aneurysms at our institute and published reports from 1964 to 2008. Eleven patients were found with CDNAs, and 138 patients were collected from the published literature. We assessed the clinical characteristics, such as sex, size, and site of CDNA, past history, and time to occurrence of CDNAs. Of 11 patients, 10 were female and 1 was male; the mean age of the first onset was 53 years (range, 25-69 years). The mean time between first aneurysms and CDNAs was 10.6 years (range, 3-29 years). The most common site of occurrence was anterior circulation. One patient experienced contralateral occurrence, and 2 patients changed from anterior to posterior circulation CDNAs. Six (54.5%) patients had a history of arterial hypertension. Results from analysis of the whole series from the literature revealed that the risk of rupture increased with a previous history of hemorrhage. Contralateral occurrence of CDNAs was related to previous location, and multiplicity, whereas the occurrence of anterior to posterior changes of CDNAs and shorter interval only correlated with an older age group.

CONCLUSION:

Although the formation of CDNAs is rare, several factors may contribute to its occurrence. Female patients with a history of arterial hypertension were at a higher risk for CDNA occurrence. We recommend follow-up imaging studies within 10 years after the initial aneurysms; therefore, at least 50% of CDNAs can be found before rupture.

De novo basilar head aneurysms--two case reports

We describe two rare cases of de novo basilar head aneurysms. The first patient presented with a ruptured basilar tip aneurysm, which developed de novo 5 years after the clipping of a left middle cerebral artery aneurysm. The second patient presented with a right basilar artery-superior cerebellar artery aneurysm, which developed de novo 3 years after the clipping of a right A(1) aneurysm. The formation of de novo aneurysm in the posterior circulation has significant implications for screening. Patients must be carefully examined not only at the sites of the initial aneurysm, but also at separate sites, including the posterior circulation, to evaluate the possibility of de novo appearance of another aneurysm.

Endovascular treatment of posterior cerebral artery aneurysms

Previous reports of outcome after endovascular treatment of posterior cerebral artery (PCA) aneurysms have been limited. This study aimed to describe the clinical outcome and angiographic results obtained in the endovascular therapy of PCA aneurysm over a six year period. Endovascular treatment strategies were determined. A retrospective analysis was performed on 18 patients with PCA aneurysms evaluated at Beijing Tiantan Hospital between December 2000 and December 2006. Nine patients presented with subarachnoid hemorrhage (SAH): one of these patients had additional seizure and hemiparesis, one had additional memory loss and oculomotor palsy and one had additional vitreous hemorrhage. One patient had an intracerebral hematoma causing hemipalsy. Nine patients demonstrated unruptured PCA aneurysms. Ten aneurysms were = or >15 mm and the other eight were <15 mm. Ten aneurysms were saccular, four were fusiform and four were giant serpentine. Eighteen aneurysms were successfully treated with one patient deceased and one with a permanent deficit, 11 with selective occlusion of the aneurysm with platinum coils, one with NBCA and five with simultaneous occlusion of the aneurysm and parent PCA with detachable coils. One patient underwent complete spontaneous thrombosis after angiography. One patient had recanalization one year after coiling and one patient (patient 13) had persistent homonymous hemianopsia and mild hemipalsy. Five patients had parent vessels were occluded with intact visual field. Clinical presentation of PCA aneurysms varied with SAH, oculomotor palsy, heminumbness, hemiparalysis, memory loss, seizure or a combination. Various aneurysms of the posterior cerebral artery can be managed effectively with endovascular treatment.

[Development of new intracranial saccular aneurysms]

Newly formed aneurysms developing from a cerebral vessel which had appeared to be normal in a previous angiographic study are very rare. Four cases of angiographically documented newly developed saccular aneurysms are described in this report. In all four patients, the new aneurysms were symptomatic, causing subarachnoid hemorrhage (SAH). Repeat angiography, performed after the second SAH, revealed new aneurysms that were not demonstrated on initial angiograms after the first SAH. They were clipped with good postoperative course. Our observations and literature data suggest that some patients with SAH need further neuroradiological followup. The presence of the risk factors and age of the patient should be taken into consideration.