Endovascular Treatment of Asymptomatic Cerebral Aneurysms: Anatomic and Technical Factors Related to Ischemic Events and Coil Stabilization

Prediction of Post-Embolization Recurrence of Anterior Communicating Aneurysms with A1 Segment Asymmetry by Fluid Dynamic Analysis

Objective

The increased surface pressure of the coil mass calculated by computational fluid dynamics (CFD) analysis has been reported to be associated with the recurrence of internal carotid aneurysms after coil embolization. In this study, we investigated the relationship between the pressure on the coil surface and the recurrence of anterior communicating aneurysms.

Methods

Among patients with anterior communicating aneurysms who underwent coil embolization at a volume embolization rate of 20% or more without using a stent, only one proximal anterior communicating artery (A1) was visualized by magnetic resonance angiography (MRA). A virtual post-coiling model was created by eliminating the aneurysm at the neck position from the blood vessel model based on three-dimensional rotational angiography (3D-RA) data before treatment, and the neck plane was defined as the virtual coil plane. Using CFD analysis, the pressure difference (PD) was calculated by subtracting the average pressure of A1 from the maximum pressure on the virtual coil surface and dividing by the dynamic pressure of A1 for normalization. PD was statistically compared between the recurrent group and the non-recurrent group.

Results

Four of 10 patients with anterior communicating aneurysms exhibited recurrence. The PD was 2.54 ± 0.24 and 2.12 ± 0.26 in the recurrent and non-recurrent groups, respectively, and was significantly higher in the recurrent group (p=0.038). In the receiver operating characteristics (ROC) analysis, the area under the curve (AUC) was 0.917, and with a cutoff value of 2.31, the sensitivity was 1.000 and the specificity was 0.833.

Conclusion

PD was considered a predictor of recurrence after coil embolization in anterior communicating aneurysms with asymmetrical A1. Preoperative prediction of recurrence after cerebral aneurysm embolization may be possible using CFD analysis.

Computational fluid dynamics (CFD) using porous media modeling predicts recurrence after coiling of cerebral aneurysms

Objective

This study aimed to predict recurrence after coil embolization of unruptured cerebral aneurysms with computational fluid dynamics (CFD) using porous media modeling (porous media CFD).

Method

A total of 37 unruptured cerebral aneurysms treated with coiling were analyzed using follow-up angiograms, simulated CFD prior to coiling (control CFD), and porous media CFD. Coiled aneurysms were classified into stable or recurrence groups according to follow-up angiogram findings. Morphological parameters, coil packing density, and hemodynamic variables were evaluated for their correlations with aneurysmal recurrence. We also calculated residual flow volumes (RFVs), a novel hemodynamic parameter used to quantify the residual aneurysm volume after simulated coiling, which has a mean fluid domain > 1.0 cm/s.

Result

Follow-up angiograms showed 24 aneurysms in the stable group and 13 in the recurrence group. Mann-Whitney U test demonstrated that maximum size, dome volume, neck width, neck area, and coil packing density were significantly different between the two groups (P < 0.05). Among the hemodynamic parameters, aneurysms in the recurrence group had significantly larger inflow and outflow areas in the control CFD and larger RFVs in the porous media CFD. Multivariate logistic regression analyses demonstrated that RFV was the only independently significant factor (odds ratio, 1.06; 95% confidence interval, 1.01–1.11; P = 0.016).

Conclusion

The study findings suggest that RFV collected under porous media modeling predicts the recurrence of coiled aneurysms.

Risk factors for angiographic recurrence after treatment of unruptured intracranial aneurysms: Outcomes from a series of 178 unruptured aneurysms treated by regular coiling or surgery

BACKGROUND

Long-term stability after intracranial aneurysm exclusion by coiling is still a matter of debate; after surgical clipping little is known.

OBJECTIVE

To study outcome after endovascular and surgical treatments for unruptured intracranial aneurysms in terms of short- and long-term angiographic exclusion and risk factors for recanalization.

METHODS

From 2004 and 2009, patients treated for unruptured berry intracranial aneurysms by coiling or clipping were reviewed. Aneurysmal exclusion was evaluated using the Roy-Raymond grading scale; immediate clinical outcome was also assessed. Clinical outcome, recanalization, risk factors for recurrence and bleeding during the follow-up period were analyzed by groups; "surgery" and "embolization".

RESULTS

From 2004 to 2009, 178 consecutive unruptured aneurysms were treated. The post-procedure angiographic results for "surgery" were: total exclusion 75.6%; residual neck 13.5%; residual aneurysm 10.8%. For "embolization", the results were, respectively: 72%; 20.7%; and 7.2%. Morbidity was 3% for "surgery" and 1.6% for "embolization" (P=0.74); mortality was nil. Mean clinical and angiographic follow-up was 5years. Recurrence rate was of 11.5% for "surgery" vs. 44% for "embolization" with a mean follow-up of 4 and 5.75years, respectively (P=1.10-5). The retreatment rate was 8.4%. Two significant risk factors for recanalization were identified: maximum diameter of the aneurysm sac (P=0.0038) and pericallosal location (P=0.0388). No bleeding event occurred.

CONCLUSION

Both techniques are safe. The rate of aneurismal recurrence was significantly higher for embolization, especially for large diameter aneurysms and pericallosal locations. No bleeding event occurred after recanalization.

Ten years of experience in endovascular treatment of ruptured aneurysms of the posterior inferior cerebellar artery

BACKGROUND

The aim of this study is to present our 10 years of experience in endovascular treatment of ruptured posterior inferior cerebellar artery (PICA) saccular aneurysms and to compare clinical presentation and outcome after endovascular treatment between patients with PICA aneurysms and patients with aneurysms in different locations.

METHODS AND FINDINGS

Out of 932 patients with a ruptured intracranial aneurysm treated endovascularly in our institution, 38 aneurysms were located at the posterior inferior cerebellar artery. Clinical presentation, mean aneurysm diameter and outcome of the therapy in this group were compared with the same for ruptured aneurysms in other locations. Patients discharged with favourable outcomes were checked angiographically in the follow-up period. Thirty-four patients with ruptured PICA aneurysms were treated by selective endovascular coiling. Two patients with wide-necked aneurysms had endovascular stents implanted. In two cases, the parent vessel was occluded due to failure to catheterise the target aneurysm. The evaluated variables did not differ significantly between two groups, but significantly more ruptured aneurysms in the PICA group were under 6 mm in diameter. 29.4% of controlled aneurysms needed additional reembolisation in the follow-up period.

CONCLUSIONS

Clinical presentation, extension of subarachnoid haemorrhage and outcome after endovascular treatment did not differ significantly between patients with ruptured aneurysms located on the PICA and patients with aneurysms located elsewhere intracranially. Endovascular treatment is an effective method of therapy in patients with ruptured PICA aneurysms. In our experience, even when sacrificing of the PICA is required, the results of treatment are favourable.

Guidelines for the Management of Patients With Unruptured Intracranial Aneurysms: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

PURPOSE

The aim of this updated statement is to provide comprehensive and evidence-based recommendations for management of patients with unruptured intracranial aneurysms.

METHODS

Writing group members used systematic literature reviews from January 1977 up to June 2014. They also reviewed contemporary published evidence-based guidelines, personal files, and published expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulated recommendations using standard American Heart Association criteria. The guideline underwent extensive peer review, including review by the Stroke Council Leadership and Stroke Scientific Statement Oversight Committees, before consideration and approval by the American Heart Association Science Advisory and Coordinating Committee.

RESULTS

Evidence-based guidelines are presented for the care of patients presenting with unruptured intracranial aneurysms. The guidelines address presentation, natural history, epidemiology, risk factors, screening, diagnosis, imaging and outcomes from surgical and endovascular treatment.

Clinical and radiologic results of endovascular coil embolization for cerebral aneurysm in young patients

Purpose

This study is an overview of the clinical and radiologic outcomes of endovascular coil embolization for cerebral aneurysm in patients aged 40 years and younger.

Materials and Methods

Between January 2008 and June 2011, 218 aneurysms were treated using endovascular coil embolization and followed up with cerebral angiography at least six months later. Twenty-one aneurysms occurred in patients aged 40 years and younger, while 197 occurred in 179 patients older than 40 years. The clinical and radiologic results were retrospectively analyzed and compared between the two groups using the modified Rankin scale scores and the modified Raymond scale.

Results

Follow-up cerebral angiography revealed two (9.5%) major and two (9.5%) minor recanalized aneurysms in patients aged 40 years and younger, and six (3.0%) major and 35 (17.7%) minor recanalized aneurysms in patients older than 40 years. However, the differences between the groups were not statistically significant. The preoperative and postoperative mean modified Rankin scale scores at time for follow-up angiography were 1.14 and 0.19 respectively for patients aged 40 years and younger, and 1.30 and 0.30 respectively for patients older than 40 years.

Conclusion

The younger patients had clinically favorable outcomes with tolerable angiographic follow-up results. More regular and long-term imaging follow-up is required for younger patients due to their longer life expectancy.

Clinical and angiographic long-term follow-up of completely coiled intracranial aneurysms using endovascular technique

Object

The anatomical evolution and clinical outcome of completely coiled intracranial aneurysms after endovascular embolization have rarely been studied separately. From their prospective database, the authors reviewed follow-up angiography and clinical outcome of 87 patients whose aneurysms were designated as 100% obliterated on immediate postembolization angiography.

Methods

Ninety-one aneurysms (56 ruptured and 35 unruptured) in 87 patients were included in this study. Clinical outcome was evaluated using the Glasgow Outcome Scale. Follow-up angiographic findings were assessed and categorized as 1 of the following: no recanalization, recanalization with a neck remnant, or recanalization with a body remnant. For statistical analysis, the recanalization rate was correlated with: clinical presentation; the largest aneurysm diameter, aneurysm neck size, and dome-to-neck ratio; aneurysm location; and use of special techniques such as usage of a surface modified coil, balloon remodeling technique, or stent.

Results

At the latest clinical evaluation (mean 34.3 months), 81 (93.1%) of the 87 patients (91 aneurysms) had good clinical outcomes (Glasgow Outcome Scale Score 5). The procedure-related morbidity rate (permanent neurological deficit) was 2.3% (2 of 87), and there were no procedure-related deaths. On the latest follow-up angiography (mean 26.4 months), the recanalization rate was 26.4% (24 of 91 aneurysms): 16 (17.6%) with neck remnants and 8 (8.8%) with body remnants. The neck size of the recanalized aneurysms was statistically significantly larger than that of the nonrecanalized aneurysms (p = 0.006), and aneurysms with wide necks (≥4 mm) had a higher recanalization rate than those with a narrow neck (< 4 mm) (p = 0.002). There was no bleeding after endovascular treatment during the follow-up period.

Conclusions

Completely coiled aneurysms after endovascular embolization demonstrated good clinical outcome, and there was no bleeding episode after endovascular treatment; however, there was a relatively high recanalization rate.

Complete obliteration of a basilar artery aneurysm after insertion of a self-expandable Leo stent into the basilar artery without coil embolization

We report a case of a 45-year-old man who underwent endovascular treatment in the acute setting of a subarachnoid hemorrhage due to rupture of a wide-necked basilar trunk aneurysm. The patient was treated with stent implantation without coiling. A control angiographic scan obtained immediately after the procedure revealed significantly decreased intraaneurysmal flow. Follow-up angiography performed after one month demonstrated total aneurysm occlusion.

Stent-assisted detachable coil embolization of pseudoaneurysms in the coronary circulation

Pseudoaneurysms in the coronary circulation are an uncommon occurrence that can develop spontaneously in the setting of atherosclerosis or can develop after catheter-based coronary interventions. The natural history, clinical outcome, and optimal therapy for pseudoaneurysms in the coronary circulation are not clearly established. Recent advances in the techniques and technologies used for endovascular treatment of intracranial aneurysms may be applicable to the management of coronary aneurysms and pseudoaneurysms. We present a case of spontaneous coronary pseudoaneurysm formation after paclitaxel drug-eluting stent implantation and a case of pseudoaneurysm formation in a saphenous vein graft that were both successfully treated with stent-assisted detachable coil embolization.