Endovascular Treatment for Lateral Wall Paraclinoid Aneurysms and the Influence of Internal Carotid Artery Angle

Stent-assisted coiling of unruptured paraclinoid aneurysms with wide neck or unfavorable dome-to-neck ratio: Results of ventral wall vs dorsal wall with propensity score matching analysis

OBJECTIVE

This study aimed to evaluate the clinical safety and efficacy of stent-assisted coil embolization of unruptured wide-necked paraclinoid aneurysms based on the projection distribution.

METHODS

Between November 2015 and September 2020, 267 unruptured paraclinod aneurysms in 236 patients were identified with a wide neck or unfavorable dome-to-neck ratio and treated with stent-assisted coiling technique. The classification of this segment aneurysms was simplified to the dorsal group (located on the anterior wall) and ventral group (Non-dorsal). Following propensity score matching analysis, the clinical and radiographic data were compared between the two groups.

RESULTS

Among 267 aneurysms, 186 were located on the ventral wall and 81 were on the dorsal wall. Dorsal wall aneurysms had a larger size (p < .001), wider neck (p = .001), and higher dome-to-neck ratio (p = .023) compared with ventral wall aneurysms. Propensity score-matched analysis found that dorsal group had a significantly higher likelihood of unfavorable results in immediate (residual sac, 39.4% vs. 18.2%, p = .007) and follow-up angiography (residual sac, 14.8% vs. 1.9%, p = .037) compared with ventral group, with significant difference in recurrence rates (9.3% vs. 0%, p = .028). The rates of procedure-related complications were not significantly different, but one thromboembolic event occurred in the dorsal group with clinical deterioration.

CONCLUSIONS

Traditional stent-assisted coiling can be given preference in paraclinoid aneurysms located on the ventral wall. The relatively high rate of recurrence in dorsal wall aneurysms with stent assistance may require other treatment options.

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020

BACKGROUND

The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time.

METHODS

A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests.

RESULTS

A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987.

CONCLUSIONS

The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

Endovascular Treatment and Microsurgical Clipping for the Management of Paraclinoid Intracranial Aneurysms: A Systematic Review and Meta-Analysis

OBJECTIVE

We aimed to compare the efficacy and safety of microsurgical clipping versus endovascular treatment (EVT) for paraclinoid aneurysms.

METHODS

A systematic search for studies including patients with paraclinoid aneurysms treated with a microsurgical or endovascular technique was conducted in 6 databases from inception to February 2022. Efficacy outcomes included complete angiographic occlusion at last follow-up, favorable functional outcome, and recurrence of the aneurysm. For safety, we assessed a composite of intraoperative and postoperative complications. Data were pooled using a random-effects model.

RESULTS

A total of 95 studies including 6711 patients, 3029 in the surgical group and 3682 in the EVT group were found. Pooled rates of complete occlusion were 94% (95% CI 91%-96%; I2 = 0%) in the surgical group and 69% (95% CI 63%-74%; I2 = 79%) in the EVT group, respectively. The favorable functional outcome rate was 86% (95% CI 76%-92%; I2 = 72%) with surgical treatment and 95% (95% CI 92%-97%; I2 = 61%) with EVT. The rate of aneurysm recurrence with surgical treatment was 1% (95% CI 0%-4%; I2 = 0%) and 12% (95% CI 9%-16%; I2 = 57%) with EVT. The composite safety outcome rate in the surgical group was 24% (95% CI 18%-30%; I2 = 90%) and 10% (95% CI 8%-13%; I2 = 71%) in the EVT group.

CONCLUSIONS

Our findings suggest that microsurgical clipping seems to have a higher efficacy than EVT in terms of angiographic occlusion and aneurysm recurrence; however, EVT seems to be safer in terms of intraoperative and postoperative complications. Considering the heterogeneity and low-level evidence of the data available, further prospective randomized studies are warranted to confirm our findings.

A Case of Horizontal Stent-assisted Coiling for an Aneurysm Arising from Fenestration of the Vertebral Artery: A Technical Case Report

Horizontal stenting protects the aneurysm neck with stent deployment across the aneurysm neck via the circle of Willis. A saccular aneurysm associated with intracranial arterial fenestration is very rare. Herein, we describe the first case of an unruptured aneurysm related to intracranial arterial fenestration treated with horizontal stenting. A 23-year-old woman presented with a 7-mm broad-necked aneurysm at the fenestration of the right intracranial vertebral artery (VA), which was incidentally found on magnetic resonance imaging. The patient underwent endovascular treatment with horizontal stenting via the vertebrobasilar junction from the contralateral left VA, followed by coil embolization using a jailed microcatheter from the ipsilateral right VA. The procedure was finished with sufficient embolization, and no complications occurred. Horizontal stent delivery via the vertebrobasilar junction for coil embolization of a broad-necked aneurysm arising from the fenestration of the VA is a safe and effective therapeutic strategy.

Increased Carotid Siphon Tortuosity Is a Risk Factor for Paraclinoid Aneurysms

Background

Geometrical factors associated with the surrounding vasculature can affect the risk of aneurysm formation. The aim of this study was to determine the association between carotid siphon curvature and the formation and development of paraclinoid aneurysms of the internal carotid artery.

Methods

Digital subtraction angiography (DSA) data from 42 patients with paraclinoid aneurysms (31 with non-aneurysmal contralateral sides) and 42 age- and gender-matched healthy controls were analyzed, retrospectively. Morphological characteristics of the carotid siphon [the posterior angle (α), anterior angle (β), and Clinoid@Ophthalmic angle (γ)] were explored via three-dimensional rotational angiography (3D RA) multiplanar reconstruction. The association between carotid siphon morphology and the formation of paraclinoid aneurysms was assessed through univariate analysis. After this, logistic regression analysis was performed to identify independent risk factors for aneurysms.

Results

Significantly smaller α, β, and γ angles were reported in the aneurysmal carotid siphon group when compared with the non-aneurysmal contralateral healthy controls. The β angle was best for discriminating between aneurysmal and non-aneurysmal carotid siphons, with an optimal threshold of 18.25°. By adjusting for hypertension, smoking habit, hyperlipidemia, and diabetes mellitus, logistic regression analysis demonstrated an independent association between the carotid siphons angles α [odds ratio (OR) 0.953; P < 0.05], β (OR 0.690; P < 0.001), and γ (OR 0.958; P < 0.01) with the risk of paraclinoid aneurysms.

Conclusions

The present findings provide evidence for the importance of morphological carotid siphon variations and the likelihood of paraclinoid aneurysms. These practical morphological parameters specific to paraclinoid aneurysms are easy to assess and may aid in risk assessment in these patients.