Endovascular treatment of posterior cerebral artery aneurysms

Microsurgery Treatment as an Optimal Management of Posterior Cerebral Artery Aneurysms: A Systematic Review and Meta-Analysis

The choice of treatment of two modalities, open surgical or endovascular, in posterior cerebral artery (PCA) intracranial aneurysms must be taken based on their special characteristics. The objective of this study is to assess the potential superiority in outcomes, operative mortality, and clinical improvement after microsurgical and endovascular management repair in PCA intracranial aneurysms. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we created this study, performing a systematic investigation on the PubMed database, with the last search carried out on June 12, 2016. The eligibility limitations were that only full text was used in the English language, and double-checking was applied. Extracted data was organized on a standard table form, including first author, publication year, general number of patients and patients at follow-up, mortality rate (with 30 days from the selecting treatment), improvement (showing postoperatively at the clinical progress (muscle strength, thinking ability, and disorientation, due to ischemic infarctions following parent vessel occlusion) for the patients of both modalities. There were eight articles that matched our study criteria. The total study population included 8,863 patients with an aneurysm, 184 (2.07%) of which had an aneurysm at the different segments of the PCA. The pooled results revealed no statistically significant difference between the two groups, in terms of mortality, but with substantial statistical results concerning clinical improvement. We concluded that the aneurysmal site and size do not influence the treatment outcome. However, clinical improvement was a statistically significant factor, demonstrating the superiority of open surgical management over endovascular treatment (EVT) for PCA aneurysms. The selection of the appropriate procedure for every case must be done based on its special characteristics.

Endovascular Treatment of the Posterior Cerebral Artery Aneurysms: Single-Center Experience and a Systematic Review

BACKGROUND

Endovascular treatment of posterior cerebral artery aneurysms is challenging because of the particular features of posterior circulation vessels. We performed a systematic review of the literature, to assess safety and efficacy associated to their endovascular treatment.

METHODS

Through a literature search, we identified 20 studies that met our inclusion criteria. We also performed a retrospective analysis of patients treated at our institution during the last 10 years. Demographics, angiographic features, clinical presentation, and outcome were extracted from each study. Data were combined using a random effects model and heterogeneity was assessed by I(2).

RESULTS

We retrieved 7 patients from our institutional series and 246 from the literature. Overall, 253/259 patients/aneurysms were included in this study. A selective coiling was performed in 27% of cases, a stent-assisted coiling in 2%, and a parent artery occlusion in 62%. Immediate complete/near-complete occlusion was obtained in 96% of cases and maintained in 90% at follow-up. No differences were observed between ruptured and unruptured aneurysms. Ischemic complications were reported in 15% of cases, although the most frequent was a hemianopsia in 7%; a hemiparesis was reported in only 2% of cases. Mortality was overall 1%. Ischemic complications were more frequent among patients who underwent nonselective treatment (P < 0.01).

CONCLUSIONS

Endovascular treatment of posterior cerebral artery aneurysms is associated with increased degree of occlusion and low recurrence rate. However, a parent artery occlusion implies complications, even although most of them are minor events such as hemianopsia.

Unruptured intracranial aneurysm treatment effects on cognitive function: a meta-analysis

OBJECTIVE

The treatment of an unruptured intracranial aneurysm (UIA) is not free of morbidity and mortality, and the decision is made by weighing the risks of treatment complications against the risk of aneurysm rupture. This meta-analysis quantitatively analyzed the literature on the effects of UIA treatment on cognition.

METHODS

MEDLINE, Embase, and PsycInfo were systematically searched for studies that reported on the cognitive status of UIA patients before and after aneurysm treatment. The search was restricted to prospective cohort and case-control studies published between January 1, 1998, and January 1, 2013. The analyses focused on the effect of treatment on general cognitive functioning, with an emphasis on 4 specific cognitive domains: executive functions, verbal and visual memory, and visuospatial functions.

RESULTS

Eight studies, with a total of 281 patients, were included in the meta-analysis. Treatment did not affect general cognitive functioning (effect size [ES] -0.22 [95% CI -0.78 to 0.34]). Executive functions and verbal memory domains trended toward posttreatment impairment (ES -0.46 [95% CI -0.93 to 0.01] and ES -0.31 [95% CI -1.24 to 0.61]), and performance of visual memory tasks trended toward posttreatment improvement (ES 1.48 [95% CI -0.36 to 3.31]). Lastly, treatment did not significantly affect visuospatial functions (ES -0.08 [95% CI -0.30 to 0.45]).

CONCLUSIONS

The treatment of an UIA does not seem to affect long-term cognitive function. However, definitive conclusions were not possible due to the paucity of studies addressing this issue.

Potential advantages and limitations of the Leo stent in endovascular treatment of complex cerebral aneurysms

OBJECTIVE

The Leo self-expandable stent is a new retractable stent that is delivered via a conventional catheter. The aim of this study was to evaluate the use of this stent for endovascular treatment of complex aneurysms.

METHODS

Twenty-eight complex cerebral aneurysms (27 saccular and 1 fusiform) in 28 patients were treated electively. They were located at the internal carotid artery (17), basilar trunk (3), anterior cerebral artery (1), anterior communicating artery (3), vertebral artery (2) and middle cerebral artery (2). One aneurysm exhibited recanalization after primary endovascular treatment without stent. Clinical outcome was assessed with the modified Glasgow Outcome Scale.

RESULTS

Deployment of Leo stent was successful in 26 lesions, and difficulties in stent positioning due to tortuous cerebral circulation in 2 cases, which were treated with Neuroform stent. Additional coil embolization was performed in 26 lesions. No permanent neurological deficits were encountered consequent to endovascular procedure. Complete or partial occlusion immediately after stent deployment was achieved in all aneurysms. There was no immediate coil embolization was chosen in 3 cases because of subsequent reduced filling of the aneurysms with contrast agent on angiograms. There were 3 asymptomatic parent artery occlusion related to the deployment of the Leo stent, one stent migration. Follow-up revealed patent stents in the remaining cases. No angiographic recurrences arose.

CONCLUSION

The Leo stent is very useful for endovascular treatment of complex cerebral aneurysms because it is easy to navigate and place precisely. A drawback is that in-stent thrombosis caused by stent placement and stiffer delivery catheters to place larger stents.

Endovascular treatment for complex intracranial aneurysms: lessons learnt in five patients

We describe our experience in five cases of endovascular treatment for complex intracranial aneurysms. The senior author (ZW) has clinical experience with more than 6000 cases of brain aneurysms treated with endovascular techniques. Multiple endovascular therapies, such as treatment with Onyx, parent vessel occlusion, stent-assisted coiling, covered stent, can be used in an attempt to provide a solution to various clinical dilemmas associated with the management of these difficult lesions. Here, we focus on the latest five patients and lessons learnt in endovascular techniques for complex intracranial aneurysms.On the basis of the knowledge obtained over the years, multimodality endovascular techniques should be re-evaluated to improve patient outcomes.

Endovascular management for p2 aneurysms of the posterior cerebral artery. Experience on proximal occlusion of the p2 segmen

This study evaluated the outcomes of endovascular management for P2-segment aneurysms. From 2003 to 2008, 14 consecutive patients with P2 aneurysms were treated endovascularly by proximal P2 segment occlusion at our institution. The aneurysms included 12 P2a and two P2p aneurysms. Presenting symptoms were caused by subarachnoid hemorrhage (SAH) in six patients, stroke in five, and isolated headaches in three. Mean follow-up was 14 months. Twelve aneurysms were treated with proximal P2 segment occlusion without parent artery revascularization. Twelve aneurysms were at the P2a and two aneurysms at the P2p. Two patients developed hemianopsia after the procedure and one recovered completely within six months follow-up with one still persistent at 22-month follow-up. Proximal parent vessel occlusion was a relatively safe, effective treatment for P2 aneurysms that posed low risk for early or delayed ischemia or infarction.

Treatment of giant intracranial aneurysms

We report on report the clinical outcome obtained in treatment of giant intracranial aneurysms (GAs). Between 2005 and 2007, 51 patients with 51 GAs presented at our hospital. Twentynine were treated with primary parent vessel occlusion without distal bypass and ten underwent treatment preserving the parent artery. Twelve patients could not be treated endovascularly. Selective embolization (including two remodeling techniques and two stent-coil mbolizations) resulted in only one cure. Two patients died as a result of subarachnoid hemorrhage periprocedurely. Twenty-nine patients treated primarily with parent vessel occlusion and three patients treated with covered stent were considered cured after their treatments. Only one patient treated with parent vessel occlusion experienced ischemia during follow-up, which resulted in a mild neurological deficit. Of the twelve patients who could not be treated endovascularly, one succumbed to surgery, four died while being treated conservatively, and three were lost to follow-up. Parent artery occlusion, covered stent and coil occlusion provide effective protection against bleeding. In treatment of paraclinoid GAs of the internal carotid rtery, the use of a stent, and stent-assisted coil embolization may be a pitfall.

Dissecting aneurysm at the proximal anterior cerebral artery treated by parent artery occlusion

Aneurysms of the A1 segment of the anterior cerebral artery (ACA) are rare. We described the first documented endovascular treatment of an A1 portion dissecting aneurysm by parent artery occlusion. A 43-year-old man patient presented with subarachnoid hemorrhage. Cerebral angiography demonstrated a dissecting aneurysm of the left anterior cerebral artery (ACA) at A1 portion. Because of the dissecting nature of the A1 portion aneurysm, a 2.5x15-mm Neuroform stent was placed in the left A1 portion. However, regrowth of the aneurysm was found on the three month follow-up angiogram, so the aneurysm and the left A1 portion of ACA were occluded completely.