Endovascular treatment of unruptured intracranial aneurysms with Guglielmi detachable coils: short- and long-term results of a single-centre series

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.

Recurrence pattern predicts aneurysm rupture after coil embolization

INTRODUCTION

Hemorrhage from a recurrent aneurysm is a major concern after coiling for intracranial aneurysms. We aimed to identify aneurysm recurrence patterns associated with hemorrhage.

MATERIAL AND METHODS

We investigated radiological data of patients who underwent coiling for intracranial aneurysms in 2008-2016 and were followed-up for at least 6 months. Aneurysm recurrence patterns were classified as: type Ⅰ, enlargement of aneurysm neck; type Ⅱ, recurrent cavity within the coil mass; type Ⅲ, recurrent cavity along the aneurysm wall; and type Ⅳ, formation of a daughter sac. We evaluated the incidence of various recurrence patterns with or without hemorrhage.

RESULTS

Of the 173 aneurysms included in the study (mean follow-up period, 32 months; range, 6-99 months), 22 (13%) recurred and required re-treatment. The recurrence patterns included type Ⅰ, Ⅱ, Ⅲ, and Ⅳ in 7 (4%), 4 (2%), 9 (5%), and 2 (1%) cases, respectively. Most of the type Ⅰ, Ⅱ, and Ⅲ recurrences occurred within 1 year, and type Ⅳ occurred at 7 years after coiling. Three aneurysms exhibited hemorrhage, one with type Ⅲ and two with type Ⅳ pattern. The two aneurysms with type Ⅳ recurrence initially occurred as type Ⅰ; however, the recurrent neck enlarged gradually, resulting in new sac formation.

CONCLUSIONS

We recommend prompt re-treatment for aneurysms recurring with type Ⅲ or Ⅳ patterns, as such patterns were associated with hemorrhage. Furthermore, we need a special care to type Ⅰ recurrence with enlargement of recurrent neck because this specific pattern may develop to type Ⅳ.

Microsurgical clipping versus newer endovascular techniques in treatment of unruptured anterior communicating artery-complex aneurysms: a meta-analysis and systematic review

The aim of this study is to compare occlusion rate, complication rate, and clinical outcome of microsurgical clipping (MC) and advanced endovascular techniques (EVT) in unruptured anterior communicating artery-complex aneurysms (ACoCAs). We reviewed the scientific literature reporting occlusion rate, time of occlusion assessment, and clinical outcome of MC and EVT in patients with unruptured ACoCAs, from January 2009 to December 2019. We included in our analysis 25 studies and 872 patients with unruptured ACoCAs (434 treated with endovascular techniques and 438 with MC). Ninety-three (10.7%), 320 (36.7%), 21 (2.4%), and 438 (50.2%) were treated with flow diverter (FD), stent-assisted coiling (SAC), endosaccular devices (ES), and microsurgical clipping (MC) respectively. FD, SAC, ES, and MC subgroups presented minor complications in 11.8%, 3.8%, 14.3%, and 7.1% of cases (p=.016), and major complications in 3.2%, 4.4%, 0%, and 7.1% (p=.136) of patients. A total occlusion rate post-treatment has been achieved in 4.3%, 87.1%, 47.6%, and 98.2% of cases (p=.000), while at 12 months' follow-up in 50%, 66%, 83.3%, and 80% of patients (p=.001). FD, SAC, ES, and MC subgroups had a good clinical outcome at 12 months in 93.5%, 90.5%, 100%, and 67.8% of cases. MC is associated with higher post-treatment total occlusion rate, but higher complication and lower good clinical outcome rates. EVT are promising in treating unruptured anterior cerebral artery aneurysms with high margin of safety and good clinical outcome, despite the lower total occlusion rate.

Characteristics of Unruptured Intracranial Aneurysms with Delayed Rupture Following Coil Embolization: Case Series and Review of the Literature

Objective

Long-term clinical outcomes including delayed rupture of unruptured intracranial aneurysms (UIAs) after coil embolization (CE) remain unclear. The purpose of this study was to evaluate the precise timing of re-treatment for recanalized UIAs before rupture.

Methods

From February 2012 to June 2020, a total of 197 patients with 207 UIAs underwent CE in our institution and were followed up for more than 6 months. The follow-up period, as well as morphological changes from treatment to recanalization, regrowth, and rupture, was retrospectively analyzed. Delayed rupture was defined as a rupture that occurred more than 1 month after CE.

Results

The average length of follow-up was 48.7 months. Three of 207 UIAs (1.45%) ruptured after CE. The aneurysm locations were the middle cerebral artery (MCA), anterior communicating artery (AcomA), and internal carotid artery-posterior communicating artery (ICA-Pcomm). The annual rupture rate after CE was 0.36%. Immediately after the first CE, treated aneurysms were graded according to the Modified Raymond-Roy Classification with class II for MCA aneurysms and class IIIb for AcomA and ICA-Pcomm aneurysms. The ICA-Pcomm aneurysm was treated with two additional CEs and was finally graded as class I. In all cases, DSA or MRA before aneurysm rupture showed recanalization and regrowth of aneurysms. The average periods from final embolization to regrowth and from regrowth to rupture were 54.3 months (±16.8) and 2.3 months (±0.9), respectively.

Conclusion

UIAs with recanalization and regrowth after CE should undergo re-treatment as early as possible.

Narrowing of the angle of the parent artery after coil embolization increases the risk for aneurysm recurrence

OBJECTIVE

Aneurysm recurrence after coiling is a major complication in some cases, including cases of repeated recurrences. In this study, we identified a relationship between the recurrence of a coiled aneurysm and angle change of the parent artery.

METHODS

From April 2008 to December 2019, we performed 283 coil embolizations to treat 256 aneurysms in 251 patients. Among these, 21 cases of recurrent saccular aneurysms were selected. The parent artery angle changes between the initial treatment and the first re-treatment were compared between those who underwent single re-treatment and showed no recurrence after the first re-treatment (Group SR, n = 14) and those who required multiple re-treatments (Group MR, n = 7).

RESULTS

The parent artery angles at the first treatment [medians (interquartile ranges)] were 121.6° (109.3-135.6°) in Group SR and 104.9° (89.9-131.0°) in Group MR; at the second treatment, these angles were 121.2° (105.5-132.7°) and 81.9° (67.0-111.4°), respectively, revealing angle changes of -2.2° (-4.0 to -0.4°) and -16.4° (-30.1 to -8.6°) in Groups SR and MR between the first and second treatments. The between-group differences in the parent artery angles at the second treatment and the changes in the parent artery angle between the first and second treatments were statistically significant.

CONCLUSION

In patients with recurrent aneurysms, simple aneurysm coiling is not effective when the angle of the parent artery becomes narrower after treatment, relative to that before treatment. Stent placement should be considered for straightening the parent artery or diverting blood flow.

Delayed Bleeding of Unruptured Intracranial Aneurysms After Coil Embolization: A Retrospective Case Series

OBJECTIVE

Delayed bleeding of unruptured intracranial aneurysms (UIAs) after coil embolization is rare; this study aimed to analyze the occurrence of delayed bleeding of UIAs after coil embolization.

METHODS

We retrospectively analyzed patients with UIAs after coil embolization between January 2002 and December 2018 and assessed the features of UIAs with delayed bleeding after coil embolization.

RESULTS

Analysis included 307 patients with 335 UIAs. Mean follow-up was 7.1 ± 4.9 years, and total follow-up was 2365 aneurysm-years. There were 271 (80.9%) aneurysms located in the anterior circulation and 64 (19.1%) aneurysms located in the posterior circulation. Significant differences were observed between the 2 groups in terms of maximum size of the aneurysm (P < 0.01), width of the aneurysm neck (P < 0.01), and number of retreatment cases (P < 0.01). During the follow-up period, delayed bleeding occurred in 4 aneurysms (annual bleeding rate of 0.17%); all were located in the posterior circulation. The original size was not relatively large (mean 8.6 ± 2.4 mm). All aneurysms bled within 5 years (mean 35 ± 9.6 months) after the initial treatment. Two were de novo aneurysms that developed adjacent to the coiled aneurysms and were not detected on follow-up magnetic resonance angiography.

CONCLUSIONS

Cautious follow-up of UIAs with digital subtraction angiography is important, articularly within the first 5 years after the procedure. If there are changes in the anatomic outcomes, short-term reassessment or additional treatment should be actively considered, particularly for aneurysms in the posterior circulation.

Long-term outcomes of endovascular simple coiling versus neurosurgical clipping of unruptured intracranial aneurysms: A systematic review and meta-analysis

BACKGROUND

Previous studies on ruptured intracranial aneurysms have shown favourable long-term outcomes of patients undergoing endovascular coiling compared to neurosurgical clipping. We aimed to evaluate if these results also apply to patients with unruptured intracranial aneurysms (UIAs).

METHODS

Embase, PubMed, and Cochrane Library were systematically searched for all studies reporting long-term (≥3 years) follow-up after coiling or clipping of UIAs. Thirteen studies involving 16,622 coiled patients and 13,606 clipped patients were included. Short-term outcome was defined as death ≤30 days after treatment. Long-term outcomes (>3 years) included all-cause mortality, morbidity (defined as modified Rankin Score 3-5 or Glasgow Outcome Score 2-3), cerebrovascular accident, intracerebral haemorrhage, additional repairs, and lost to follow-up. We calculated relative risk (RR), incidence and mortality rates (IR and MR), together with incidence and mortality rate ratio (IRR and MRR).

RESULTS

Patients treated with simple coiling had lower short-term mortality than clipped patients (RR = 0.62 (95%CI 0.42-0.91)), but this difference disappeared after long-term follow-up ((MRR) = 0.89 (95%CI: 0.78-1.02). Coiled patients had higher retreatment rates than clipped patients (IRR = 1.70 (95%CI 1.50-1.93)).

CONCLUSIONS

This systematic review and meta-analysis reports benefits and drawbacks of simple coiling versus neurosurgical clipping of UIAs. Future studies with longer follow-up time should account for differences in coiling techniques and confounding factors such as size and location of UIAs.

Stent-Assisted Coiling of Unruptured MCA Aneurysms Using the LVIS Jr. Device: A Multicenter Registry

Purpose: The low-profile visualized intraluminal support junior (LVIS Jr.) is a new generation low-profile braided stent. Our aim was to evaluate the safety and efficacy of the LVIS Jr. in the stent-assisted coiling of unruptured middle cerebral artery (MCA) aneurysms. This was a multicenter retrospective study. Patient demographics, aneurysm characteristics, procedural details, complications, and the results of clinical and imaging follow-up were analyzed. Four centers participated in the study. A total of 162 consecutive patients with 162 unruptured MCA aneurysms were included for the analysis. The mean aneurysm size was 7.6 mm (range 2 to 37 mm) and 97.5% were wide-necked. Immediate postprocedural angiograms showed Raymond-Roy class 1 in 118 (72.8%), class 2 in 23 (14.2%), and class 3 in 21 patients (13%). Periprocedural complications occurred in 14 patients (8.6%). There were no procedure-related deaths. Follow-up imaging at 12–18 months post-procedure showed Raymond–Roy class 1 in 132 (81.5%), class 2 in 17 (10.5%), and class 3 in 13 patients (8%). There were 3 cases of in-stent stenosis (1.9%). All 162 patients had good clinical outcome (mRS score 0–2) at 90 days post-procedure. Stent-assisted coiling of unruptured MCA aneurysms with the LVIS Jr. stent is safe and effective, with high immediate and long-term total occlusion rates.

Long-Term Rupture Risk in Patients with Unruptured Intracranial Aneurysms Treated with Endovascular Therapy: A Systematic Review and Meta-Analysis

BACKGROUND

Surveillance imaging of previously unruptured, coiled aneurysms remains routine even though reports of rupture of these aneurysms are extremely rare.

PURPOSE

We performed meta-analysis to examine long-term rupture risk over ≥1-year follow-up duration in patients with unruptured intracranial aneurysm who underwent endovascular therapy.

DATA SOURCES

Multiple databases were searched for relevant publications between 1995 and 2018.

STUDY SELECTION

Studies reporting outcome of long-term rupture risk over ≥1-year follow-up in treated patients with unruptured intracranial aneurysms were included.

DATA ANALYSIS

Random effects meta-analysis was used, and results were expressed as long-term rupture rate per 100 patient-year with respective 95% CIs. For ruptured aneurysms during follow-up, data were collected on size and completeness of initial Treatment.

DATA SYNTHESIS

Twenty-four studies were identified. Among 4842 patients with a mean follow-up duration of 3.2 years, a total of 12 patients (0.25%) experienced rupture of previous unruptured intracranial aneurysms after endovascular treatment. Nine of these 12 patients harbored aneurysms that were large, incompletely treated, or both. A total of 2 anterior circulation, small, completely coiled aneurysms subsequently ruptured. The long-term rupture rate per 100 patient-year for unruptured intracranial aneurysms treated with endovascular therapy was 0.48 (95% CI, 0.45-0.51). Retreatment was carried out in 236 (4.9%) of these 4842 patients.

LIMITATIONS

A limitation of the study is that a lack of systematic nature of follow-up and mean follow-up duration of 3.2 years are not sufficient to make general recommendations about aneurysm followup paradigms.

CONCLUSIONS

Given a 5% retreatment rate, postcoil embolization spontaneous rupture of previously unruptured, small- and medium-sized, well-treated aneurysms is exceedingly rare.

Stent-Assisted Coiling of Intracranial Aneurysms Using a Nitinol-Based Stent (Neuroform Atlas): A Systematic Review and Meta-analysis

OBJECTIVE

The aim of this systematic review and meta-analysis was to synthesize the latest evidence on the efficacy and safety of Neuroform Atlas-assisted coiling of intracranial aneurysms.

METHODS

We performed a comprehensive search for articles that assessed the efficacy and safety of Neuroform Atlas-assisted coiling of intracranial aneurysms. The outcome measurement was adequate occlusion, defined as Raymond-Roy Class I (RR1) + Raymond-Roy Class II (RR2) by previous studies.

RESULTS

A total of 557 patients (568 aneurysms) from 13 studies were included. The rate of adequate occlusion after the procedure was 88% (83-94%, I²: 72.21%), and the rates of RR1 and RR2 were 68% (60-77%, I²: 81.87%) and 21% (15-27%, I²: 66.10%), respectively. The adequate occlusion rate at 6 months was 90% (81-99%, I²: 58.04%) and 93% (91-96%, I²: 0%) at the end of a mean of 9.03 ± 1.03 months of follow-up. Periprocedural complications occurred in 35 patients [5% (3-8%, I²: 21.28%)]. Subgroup analysis of unruptured aneurysms showed that the rates of adequate occlusion were 85% (78-93%), 90% (79-100%) (6-month follow-up), and 93% (90-96%) (at the end of follow-up). For the wide-necked aneurysm subgroup, the rate of adequate occlusion was 86% (80-93%) and was 93% (89-97%) at the end of follow-up. Meta-regression showed that initial adequate occlusion was influenced by mean aneurysm neck size (p = 0.034).

CONCLUSION

Neuroform Atlas-assisted coiling is associated with an initial adequate occlusion rate of 88% and a periprocedural complication rate of 6%. The rate of initial adequate occlusion was 85% in unruptured aneurysms and 86% in wide-necked aneurysms.

LEVEL OF EVIDENCE

Level 2, Systematic review of non-randomized and single-arm studies.

Rupture of Intradural Giant Aneurysms: The Mode of Treatment, Anatomical, and Mechanical Factors

OBJECTIVE

Aneurysm rupture is often a fatal complication of giant intradural aneurysm (GIA) treatments. The purpose of this study was to review aneurysm rupture in GIA treatment.

MATERIALS AND METHODS

We performed a systematic review on aneurysm rupture related to GIA treatment. For each reported case, we collected the following information: aneurysm location, size and rupture status, the mode of treatment, timing of the hemorrhage, anatomical, and hemodynamic factors.

RESULTS

We identified 56 aneurysm ruptures related to treatment in 38 published studies. Of the nine intraoperative ruptures, eight occurred during endovascular procedures and one in surgical treatment. Of the 47 delayed ruptures, 72.3% occurred within 2 weeks. The prognosis of intraoperative and delayed ruptures was poor, with 83.9% experiencing death. Of these aneurysms, 75% were initially unruptured. Of the delayed ruptured aneurysms, 21.3% had prior surgical treatment, 74.4% had prior endovascular treatment, and 4.3% had prior combined surgical and endovascular treatments. Vertebrobasilar artery (VBA) location was significantly associated with aneurysm rupture after treatment, occurring at 57.2%. Flow diverter (FD) treatment seemed to elevate the delayed rupture proportion of giant paraclinoid internal carotid artery (ICA) aneurysms from 22.0% to 42.9%. FD treatment did not lower the rupture risk of giant VBA aneurysms and the corresponding death rate.

CONCLUSION

Intraoperative and delayed aneurysm ruptures were the most challenging in endovascular treatment of GIAs. Giant VBA aneurysm had the highest rupture risk after treatment. FD seemed to elevate the delayed rupture proportion of giant paraclinoid aneurysms.

Practical Incidence of Complications and Degree of Patient Satisfaction After Endovascular Coil Embolization for Unruptured Intracranial Saccular Aneurysm Based on Patients' Surveys

OBJECTIVE

Endovascular treatment for unruptured intracranial aneurysms (UIAs) has been regarded as second to none management nowadays as the result of its proven efficacy and need for less-invasive treatment. Most researchers have focused on the anatomical outcome after endovascular treatment, so in this study we estimated the real incidence of untoward effect and degree of patients' satisfaction based on s survey.

METHODS

This retrospective study was approved by the institutional review board, and 112 patients treated for saccular UIAs were evaluated among a total of 135 patients. After informed consent was obtained, these patients were sent a questionnaire regarding treatment effectiveness, complications, and patient satisfaction. These data were collected and compared with angiographic and clinical outcome.

RESULTS

The response rate was 87.5% (98/112). Intracranial complications occurred in 10 aneurysms (10.2%): 7 ischemic and 3 hemorrhagic strokes. Other complications occurred in 30 patients (30.6%): 17 alopecia, 15 bleeding tendency, and 3 puncture-site complications. Overall, 89 (90.8%) patients reported being satisfied with their treatment. Patient satisfaction was closely correlated with clinically successful outcome of treatment.

CONCLUSIONS

Ninety percent of patients were satisfied with the results after endovascular treatment of UIAs. Endovascular coil embolization was effective and safe procedure, with high clinical success rate and degree of satisfaction.

Bailout Strategies and Complications Associated with the Use of Flow-Diverting Stents for Treating Intracranial Aneurysms

Background

Flow-diverting stents (FDS) have revolutionized the endovascular management of unruptured, complex, wide-necked, and giant aneurysms. There is no consensus on management of complications associated with the placement of these devices. This review focuses on the management of complications of FDS for the treatment of intracranial aneurysms.

Summary

We performed a systematic, qualitative review using electronic databases MEDLINE and Google Scholar. Complications of FDS placement generally occur during the perioperative period.

Key Message

Complications associated with FDS may be divided into periprocedural complications, immediate postprocedural complications, and delayed complications. We sought to review these complications and novel management strategies that have been reported in the literature.

Endovascular Treatment of Very Large and Giant Intracranial Aneurysms: Comparison between Reconstructive and Deconstructive Techniques-A Meta-Analysis

BACKGROUND

The safety and efficacy of reconstructive and deconstructive endovascular treatments of very large/giant intracranial aneurysms are not completely clear.

PURPOSE

Our aim was to compare treatment-related outcomes between these 2 techniques.

DATA SOURCES

A systematic search of 3 data bases was performed for studies published from 1990 to 2017.

STUDY SELECTION

We selected series of reconstructive and deconstructive treatments with >10 patients.

DATA ANALYSIS

Random-effects meta-analysis was used to analyze occlusion rates, complications, and neurologic outcomes.

DATA SYNTHESIS

Thirty-nine studies evaluating 894 very large/giant aneurysms were included. Long-term occlusion of unruptured aneurysms was 71% and 93% after reconstructive and deconstructive treatments, respectively (P = .003). Among unruptured aneurysms, complications were lower after parent artery occlusion (16% versus 30%, P = .05), whereas among ruptured lesions, complications were lower after reconstructive techniques (34% versus 38%). Parent artery occlusion in the posterior circulation had higher complications compared with in the anterior circulation (36% versus 15%, P = .001). Overall, coiling yielded lower complication and occlusion rates compared with flow diverters and stent-assisted coiling. Complication rates of flow diversion were lower in the anterior circulation (17% versus 41%, P < .01). Among unruptured lesions, early aneurysm rupture (within 30 days) was slightly higher after reconstructive treatment (5% versus 0%, P = .08) and after flow diversion alone compared with flow diversion plus coiling (7% versus 0%).

LIMITATIONS

Limitations were selection and publication biases.

CONCLUSIONS

Parent artery occlusion allowed high rates of occlusion with an acceptable rate of complications for unruptured, anterior circulation aneurysms. Coiling should be preferred for posterior circulation and ruptured lesions, whereas flow diversion is relatively safe and effective for unruptured anterior circulation aneurysms.

Rescue Therapy for Procedural Complications Associated With Deployment of Flow-Diverting Devices in Cerebral Aneurysms

Flow diverting devices (FDDs) have revolutionized the treatment of morphologically complex intracranial aneurysms such as wide-necked, giant, or fusiform aneurysms. Although FDDs are extremely effective, they carry a small yet significant risk of intraprocedural complications. As the implementation of these devices increases, the ability to predict and rapidly treat complications, especially those that are iatrogenic or intraprocedural in nature, is becoming increasingly more necessary.

Our objective in this paper is to provide a descriptive summary of the various types of intraprocedural complications that may occur during FDDs deployment and how they may best be treated. A systematic and qualitative review of the literature was conducted using electronic databases MEDLINE and Google Scholar. Searches consisted of Boolean operators “AND” and “OR” for the following terms in different combinations: “aneurysm,” “endovascular,” “flow diverter,” “intracranial,” and “pipeline.”

A total of 94 papers were included in our analysis; approximately 87 of these papers dealt with periprocedural endovascular (mainly related to FDDs) complications and their treatment; 7 studies concerned background material. The main categories of periprocedural complications encountered during deployment of FDDs are failure of occlusion, parent vessel injury and/or rupture, spontaneous intraparenchymal hemorrhage, migration or malposition of the FDDs, thromboembolic or ischemic events, and side branch occlusion

Periprocedural complications occur mainly due to thromboembolic events or mechanical issues related to device deployment and placement. With increasing use and expanding versatility of FDDs, the understanding of these complications is vital in order to effectively manage such situations in a timely manner.

Subarachnoid Hemorrhage: An Update

Subarachnoid hemorrhage (SAH) is a debilitating, although uncommon, type of stroke with high morbidity, mortality, and economic impact. Modern 30-day mortality is as high as 40%, and about 50% of survivors have permanent disability. Care at high-volume centers with dedicated neurointensive care units is recommended. Euvolemia, not hypervolemia, should be targeted, and the aneurysm should be secured early. Neither statin therapy nor magnesium infusions should be initiated for delayed cerebral ischemia. Cerebral vasospasm is just one component of delayed cerebral edema. Hyponatremia is common in subarachnoid hemorrhage and is associated with longer length of stay, but not increased mortality.

The role of endovascular treatment in unruptured basilar tip aneurysms

Objective This study was to evaluate the safety and efficiency of endovascular treatment of unruptured basilar tip aneurysms. Methods We retrospectively reviewed consecutive 79 cases of unruptured basilar tip aneurysms in our center between 2009 and 2014. The patients' clinical and imaging information were recorded. Complications, initial occlusion rate, clinical outcomes and the predictors were retrospectively analyzed. Results Thirty-five cases received conservative treatment and 44 cases were treated by endovascular embolization. In the conservative treatment group, six (19.4%) of 31 basilar tip aneurysms ruptured and resulted in five deaths (16.1%) during the mean 18.1-month follow-up (range from 1 to 60 months). Among the endovascularly treated cases, 24 (54.5%) achieved initial complete occlusion and no delayed hemorrhagic events occurred during the mean 33.6-month follow-up (range from 10 to 68 months). For 20 (45.5%) incompletely occluded cases, five postoperative or delayed hemorrhagic events and two mass effect events resulted in six deaths. There were no statistical significant differences in hemorrhagic events ( p = 0.732) and mortality ( p = 0.502) between the incomplete occlusion group and untreated group. Large aneurysm size (≥10 mm) was an independent predictor for incomplete occlusion ( p = 0.002), which had a potential risk of postoperative or delayed hemorrhage. On univariate analysis, initial occlusion rate and aneurysm size were found to be associated with clinical outcomes ( p = 0.042 and 0.015). Conclusion Complete occlusion for unruptured basilar tip aneurysm proved to be a safe and effective therapeutic method that could eliminate the potential risk of postoperative or delayed hemorrhage.

Blood Flow Into Basilar Tip Aneurysms

Background and Purpose—

Hemodynamic forces may play a role in the recanalization of coiled aneurysms. The purpose of this study was to investigate the influence of presurgical hemodynamics on the efficacy of coil embolization for basilar tip aneurysms.

Methods—

We identified 82 patients who underwent endovascular coil embolization for basilar tip aneurysms with a follow-up of >1 year. Presurgical hemodynamics were investigated using computational fluid dynamics with 3-dimensional data derived from rotational angiography. During postprocessing, we quantified the rate of net flow entering the aneurysm through its neck and calculated the proportion of the aneurysmal inflow rate to the basilar artery flow rate. In addition, we investigated the correlation between the basilar bifurcation configuration and the hemodynamics.

Results—

Twenty-five of the 82 patients were excluded because of difficult vascular geometry reconstruction. Among the 57 examined patients, angiographic recanalization was observed in 19 patients (33.3%). The proportion of the aneurysmal inflow rate to the basilar artery flow rate and a coil packing density <30% were independent and significant predictors for the recanalization of coiled aneurysms. Additional investigation revealed that a small branch angle formed by the basilar artery and the posterior cerebral artery increased blood flow into the aneurysm.

Conclusions—

The proportion of the aneurysmal inflow rate to the basilar artery flow rate, influenced by the basilar bifurcation configuration, was an independent and significant predictor for recanalization after coil embolization in basilar tip aneurysms.

Endovascular treatment of unruptured posterior circulation intracranial aneurysms

BACKGROUND AND PURPOSE

Endovascular treatment of unruptured posterior circulation intracranial aneurysms (UPCIAs) is limited in the International Study of Unruptured Intracranial Aneurysms (ISUIA). The aim of this study is to evaluate the periprocedural morbidity, mortality, and midterm clinical and angiographic follow-ups of endovascular treatment of UPCIAs.

MATERIALS AND METHODS

Retrospective analysis of all patients treated in a 2-year period (89 patients: 10-78 years of age, mean: 45.5 ± 14.3/92 UPCIAs). Fifty-eight aneurysms were found incidentally, 12 in association with mass effect symptoms and 22 with stroke.

RESULTS

A clinical improvement or stable outcome was achieved in 84 patients (94.4%). The two cases of permanent morbidity included a patient with paralysis and another patient with hemianopia. One patient died after treatment of a giant fusiform vertebrobasilar aneurysm. In one patient, the aneurysm ruptured during treatment, resulting in death. Another patient suffered a fatal aneurysm rupture 4 days after treatment. Giant size (P = 0.005) and mass effect presentation (P = 0.029) were independent predictors of unfavorable outcomes in UPCIAs. Angiographic follow-up was available in 76 of the 86 surviving patients (88.4%) with a mean of 6.8 months (range: 1-36 months). Recanalization in six patients (7.9%) at 3 months, 4 months, 4 months, 24 months, and 36 months required retreatment in three patients. In-stent stenosis of >50% was found in three patients.

CONCLUSION

Endovascular therapy is an attractive option for UPCIAs with stable midterm outcome. However, the current endovascular option seems to have a limitation for the treatment of the aneurysm with giant size or mass effect presentation.

Construction of 3 animal experimental models in the development of honeycomb microporous covered stents for the treatment of large wide-necked cerebral aneurysms

The treatment of large or wide-necked cerebral aneurysms is extremely difficult, and carries a high risk of rupture, even when surgical or endovascular methods are available. We are developing novel honeycomb microporous covered stents for treating such aneurysms. In this study, 3 experimental animal models were designed and evaluated quantitatively before preclinical study. The stents were prepared using specially designed balloon-expandable stents (diameter 3.5-5.0 mm, length 16-28 mm) by dip-coating to completely cover their struts with polyurethane film (thickness 20 µm) and microprocessing to form the honeycomb pattern after expansion. (1) In an internal carotid artery canine model (n = 4), all stents mounted on the delivery catheter passed smoothly through the tortuous vessel with minimal arterial damage. (2) In an the large, wide-necked, outer-sidewall aneurysm canine model, almost all parts of the aneurysms had embolized immediately after stenting (n = 4), and histological examination at 2 months revealed neointimal formation with complete endothelialization at all stented segments and entirely organized aneurysms. (3) In a perforating artery rabbit model, all lumbar arteries remained patent (n = 3), with minimal change in the vascular flow pattern for over 1 year, even after placement of a second, overlapping stent (n = 3). At 2 months after stenting, the luminal surface was covered with complete thin neointimal formation. Excellent embolization performance of the honeycomb microporous covered stents without disturbing branching flow was confirmed at the aneurysms in this proof-of-concept study.

Non-pulsatile traumatic pseudoaneurysm of the internal maxillary artery following trauma to mandible

Traumatic pseudoaneurysm involving the maxillary artery is rare. Owing to its anatomic location, internal maxillary artery is usually protected by its surrounding structures. Formation of pseudoaneurysm usually takes place after several weeks to months of the initial injury. In this case, we reported a pseudoaneurysm arising from left internal maxillary artery following blunt injuries within 3 hours after a road accident and the treatment with endovascular embolization with titanium coils prior to open reduction and internal fixation of the fractured mandibles.

Vertebro-basilar junction aneurysms: a single centre experience and meta-analysis of endovascular treatments

Vascular lesions of the vertebrobasilar junction (VBJ) are challenging in neurosurgical practice, and their gold-standard therapy is still under debate. We describe the operative strategies currently in use for the management of these complex vascular lesions and discuss their rationale in a literature meta-analysis and single centre blinded retrospective study. The single centre study included a review of initial presentation, angiographic features and clinical outcome (with modified Rankin Scale [mRS] scores) over a long-term follow-up. In our series, small aneurysms were effectively treated by endosaccular coil embolization, whereas a strategy including flow-diverter devices combined with endosaccular coil embolization was the option of choice in large and giant aneurysms, leading to satisfactory outcomes in most cases. Our Medline review showed that endovascular treatment was chosen in most VBJ cases, whereas the microsurgical option was assigned to only a few cases. Among the endovascular treatments, the most common techniques used for the treatment of VBJ aneurysms were: coiling, stent-assisted coiling and flow diversion. Our study highlights that aneurysm morphology, location and patient-specific angio-architecture are key factors to be considered in the management of VBJ aneurysms. Most case series, including our own, show that parent artery reconstruction using a flow-diverter device is a feasible and successful technique in some cases of giant and complex aneurysms (especially those involving the lower third of the basilar artery) while a "sit back, wait and see" approach may represent the safest and most reasonable option.

Surpass flow diverter in the treatment of intracranial aneurysms: a prospective multicenter study

BACKGROUND AND PURPOSE

Incomplete occlusion and recanalization of large and wide-neck brain aneurysms treated by endovascular therapy remains a challenge. We present preliminary clinical and angiographic results of an experimentally optimized Surpass flow diverter for treatment of intracranial aneurysms in a prospective, multicenter, nonrandomized, single-arm study.

MATERIALS AND METHODS

At 24 centers, 165 patients with 190 intracranial aneurysms of the anterior and posterior circulations were enrolled. The primary efficacy end point was the percentage of intracranial aneurysms with 100% occlusion on 6-month DSA. The primary safety end point was neurologic death and any stroke through a minimum follow-up of 6 months.

RESULTS

Successful flow-diverter delivery was achieved in 161 patients with 186 aneurysms (98%); the mean number of devices used per aneurysm was 1.05. Clinical follow-up (median, 6 months) of 150 patients (93.2%), showed that the primary safety end point occurred in 18 subjects. Permanent neurologic morbidity and mortality were 6% and 2.7%, respectively. Morbidity occurred in 4% and 7.4% of patients treated for aneurysms of the anterior and posterior circulation, respectively. Neurologic death during follow-up was observed in 1.6% and 7.4% of patients with treated intracranial aneurysms of the anterior and posterior circulation, respectively. Ischemic stroke at ≤30 days, SAH at ≤7 days, and intraparenchymal hemorrhage at ≤7 days were encountered in 3.7%, 2.5%, and 2.5% of subjects, respectively. No disabling ischemic strokes at >30 days or SAH at >7 days occurred. New or worsening cranial nerve deficit was observed in 2.7%. Follow-up angiography available in 158 (86.8%) intracranial aneurysms showed 100% occlusion in 75%.

CONCLUSIONS

Clinical outcomes of the Surpass flow diverter in the treatment of intracranial aneurysms show a safety profile that is comparable with that of stent-assisted coil embolization. Angiographic results showed a high rate of intracranial aneurysm occlusion.

Delayed rupture of a basilar artery aneurysm treated with coils: case report and review of the literature

Delayed rupture of a previously unruptured cerebral aneurysm after uneventful saccular coil packing is rare, particularly when the quality of aneurysm occlusion is appropriate (neck remnant or total occlusion). The present report describes the case of a 70-year-old woman with an incidentally detected, asymptomatic, small basilar tip non-thrombosed aneurysm who experienced rupture of the aneurysm 2 years after coiling. Cerebral angiography taken on the day of rupture revealed only small recanalization of the aneurysm neck with no dome-filling. This is the first report of delayed rupture due to minor recurrence of a previously unruptured small asymptomatic cerebral aneurysm after saccular coil packing. A literature review of 26 reports of late bleeding after coil embolization of previously unruptured cerebral aneurysms showed that dome-filling after coil embolization, symptomatic aneurysms and large/giant aneurysms all increase the risk of delayed rupture in previously unruptured aneurysms after saccular coil packing.

Effect of core laboratory and multiple-reader interpretation of angiographic images on follow-up outcomes of coiled cerebral aneurysms: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Reported rates of recanalization following coil embolization vary widely across studies. Some confounders are known to affect outcomes but others remain questionable. In the current study, we assess differences in reported angiographic outcomes for cerebral aneurysms treated with coil embolization as a function of single vs multiple readers and site investigator vs core laboratory settings.

MATERIALS AND METHODS

Our systematic review covered 1999-2011 by using Ovid MEDLINE and EMBASE. Search terms were subarachnoid hemorrhage, intracranial aneurysms, endovascular treatment, and coiling. Inclusion criteria were >50 aneurysms and available imaging follow-up. Study characteristics of interest were readers at the treating site(s) or at an independent core imaging facility, single vs multiple readers, number of aneurysms treated, mean aneurysm size, mean follow-up time, coil type, initial rupture status, and angiographic follow-up. We defined "unfavorable angiographic outcome" as either "recanalization," <90% occlusion, or "incomplete occlusion."

RESULTS

There were 104 (2.6%) of 4022 studies that fulfilled our inclusion criteria, comprising a total of 22,134 treated aneurysms, of which 15,969 (72.1%) had reported angiographic follow-up. The overall unfavorable outcome rate was 17.8% (2955/15,969 aneurysms). Eight (7.7%) of 104 studies reported core laboratory readings in which the pooled rate of unfavorable outcomes was 0.23 (95% CI, 0.19-0.28) compared with 0.16 (95% CI, 0.14-0.18) in readings from the treating sites (P < .001). The multivariate meta-regression suggested that core laboratory interpretation was significant for unfavorable outcomes (OR, 5.60; 95% CI, 2.01-15.60; P = .001), after adjustment for initial rupture status, aneurysm size, follow-up duration, and coil type. No significant association was found with use of multiple readers.

CONCLUSIONS

Core laboratory studies tend to report higher rates of unfavorable outcomes compared with self-reported studies.

Results of Stent-Assisted vs Non-Stent-Assisted Endovascular Therapies in 489 Cerebral Aneurysms

BACKGROUND:

Whether the addition of stenting to intracranial aneurysm coil embolization results in benefit in terms of occlusion rates or additional risk in terms of periprocedural adverse events is not clear.

OBJECTIVE:

To report retrospectively analyzed results of endovascular aneurysm treatment comparing stent-assisted coiling with coiling without stents at our hospital from 2005 to 2009.

METHODS:

In this retrospectively reviewed case series, aneurysms were grouped as intent-to-treat or initially treated with stent-assisted coiling (A) vs coiling alone (B) or as-treated—those that ultimately received a stent (C) or not (D). Complication and occlusion rates were compared between groups. Some patients crossed from group B to C after receiving stent placement at a later treatment following the initial therapeutic modality (without a stent).

RESULTS:

In 459 patients, 489 aneurysms were treated by group as follows: A = 181, B = 308, C = 225, and D = 264. In stent groups (A and C), there were significantly lower frequencies of ruptured aneurysms (A vs B = 11% vs 62%, P &lt; .001; C vs D = 20.4% vs 62.5%, P &lt; .001) and more giant aneurysms (A vs B = 7.3% vs 1.0%, P = .001; C vs D = 5.9% vs 1.1%, P &lt; .001). There was no statistically significant difference in permanent event-related morbidity (A vs B = 4.4% vs 4.2%, P = 1.0; C vs D = 4.4% vs 4.2%, P = 1.0). Average angiographic follow-up after last treatment was 18.2 ± 15 months (median = 14). Higher rates of complete occlusion at last angiographic follow-up were observed in stented aneurysms (A vs B = 64.6% vs 49.7%, P = .001; C vs D = 62.7% vs 48.9%, P = .003).

CONCLUSION:

Stent-assisted aneurysm treatment resulted in higher total occlusion rates than non-stent-assisted treatment, with acceptable, comparable periprocedural event rates.

Surgery for unruptured intracranial aneurysms in the ISAT and ISUIA era

BACKGROUND

The ISAT and ISUIA studies, along with the improvement of endovascular treatment (EVT) have strongly influenced the management of intracranial aneurysms (IAs). We present our experience in the microsurgical treatment of unruptured IAs (UIAs) in this context.

METHODS

We retrospectively reviewed a consecutive series of non-giant UIAs selected for surgery during a five-year period. Patients and aneurysms characteristics, surgical results and outcome assessed by the Glascow Outcome Scale (GOS) at three month follow-up were studied.

RESULTS

Eighty-five patients underwent 93 surgical procedures to obliterate 113 UIAs. Those were incidental in 89% of the cases and mainly located on the middle cerebral artery (65%). Patients were assigned to surgery according to their medical history (young, previous subarachnoid haemorrhage), aneurysm characteristics (wide neck, branch at the neck, "small" size, associated "surgical" aneurysm) or failure of EVT (5%). Operatively, 48% of UIAs had thin wall or blebs and 71% were occluded with one titanium clip. Thrombectomy or temporary clipping were necessary in 4% and 11% of the cases, three aneurysms peroperatively ruptured, four were deemed unclippable, three paraclinoid UIAs had an intracavernous residue and 16% were wrapped because of a small neck remnant (class 2). The mortality rate was 0% and 4% of the patients experienced a definitive major neurological deterioration. Final GOS was unchanged in 96% of the patients.

CONCLUSIONS

Despite reduction in operative cases and in appropriately selected patients ineligible to EVT, microsurgical clipping of non-giant anterior circulation UIAs can still achieve good outcome with very low mortality and neurological morbidity.

Endovascular therapy of 500 small asymptomatic unruptured intracranial aneurysms

BACKGROUND AND PURPOSE

Although the natural course of UIAs remains unclear, the risk of aneurysmal SAH due to small (<10 mm) asymptomatic UIAs is low. Endovascular therapy for UIAs has increased because of device development and the need for less invasive treatment. We report the results, safety, and efficacy of endovascular therapy of small asymptomatic UIAs.

MATERIALS AND METHODS

A total of 457 patients with 500 small asymptomatic UIAs (maximum diameter < 10 mm) underwent endosaccular coil embolization at Juntendo University Hospital and affiliated hospitals. We retrospectively evaluated the technical feasibility, immediate and short-to-midterm follow-up anatomic results, procedure-related complications, and clinical outcomes.

RESULTS

Endosaccular coil embolization was completed in 481 aneurysms (96.2%) and attempted in 19 (3.8%). Completed aneurysms were treated with the simple (39.5%), balloon-assisted (51.4%), and double-catheter (9.1%) techniques. Immediate angiographic outcomes were CO for 309 (64.2%) aneurysms, RN for 72 (15.0%), and RA for 100 (20.8%). Procedure-related complications occurred in 38 aneurysms (7.6%): 19 ischemic, 11 hemorrhagic, and 8 others. Permanent morbidity and mortality were 0.8% and 0.2%, respectively. Anatomic outcome of 427 aneurysms followed up for >6 months with conventional catheter or MR angiographies showed recanalization in 72 (16.9%) aneurysms, necessitating retreatment in 9.9% (mean, 31.4 months). No patients had aneurysmal SAH during the clinical follow-up period (mean, 34.7 months).

CONCLUSIONS

In this series, endovascular therapy of small asymptomatic UIAs was highly feasible with low morbidity and mortality rates.

Endovascular treatment of unruptured intracranial aneurysms

We report the clinical and angiographic results of endovascular treatment of unruptured intracranial aneurysms. Over a three-year period, 80 unruptured aneurysms in 74 patients were electively treated with endovascular management. One aneurysm was diagnosed during investigations for a second ruptured aneurysm, 54 aneurysms were incidentally discovered, 18 aneurysms presented with symptoms of mass effect and seven aneurysms presented with symptoms of brain stem ischemia. Mean size of the 80 unruptured aneurysms was 12.5±8.0 mm (range, 2-39 mm). Thirty-six aneurysms (45%) were small (<10 mm), 38 aneurysms (47.5%) were large (10-25 mm), and six aneurysms (7.5%) were giant (25-39 mm). Forty-eight wide-necked aneurysms (60%) were coiled with the aid of a supporting device. The mortality rate was 1.25%, and the overall morbidity was 1.25%. Of these, one of the patients suffered a stroke, leading to severe disability (1.25%). In one patient, the aneurysm ruptured during treatment, resulting in death. Initial aneurysm occlusion was complete (100%) in 76.25% aneurysms, nearly complete (90%-98%) in 10% aneurysms and incomplete (60%-85%) in 13.75% aneurysms. Follow-up angiography was available in 67 patients with 73 treated aneurysms (91.25%) from one to 36 months (mean 9.3 months); partial reopening occurred in 7.5%, mainly large and giant aneurysms (5.5%). Additional coiling was performed in four aneurysms. There were no complications in additional treatments. At 14.1-month clinical follow-up (range, 2 to 36 months), mRS score was 0 in 78.75% patients, 1 in 10% patients, 2 in 8.75% and 3 in 1.25%. There was no aneurysmal rupture during the follow-up period. Endovascular treatment of unruptured intracranial aneurysms has low procedural mortality and morbidity rates.

[Endovascular therapy options for aneurysmal subarachnoid hemorrhage]

Aneurysmal subarachnoid hemorrhaging (ASH) is a severe condition with an acute symptomatic, often with a difficult course and accompanied by many complications. Aneurysms can be detected using computed tomography (CT), magnetic resonance angiography (MRA) and digital subtraction angiography (DSA). Possible therapy options for ASH are surgical clipping and endovascular treatment using platinum coils. The surgical approach is an effective and safe method for avoiding recurrent bleeding.So-called Guglielmi detachable coils, with which aneurysms can be successfully embolized, have been available since 1991. Initially only a few different sizes of platinum coils were available but now complex forms of platinum coils with different lengths and rigidness are available so that many forms of aneurysm can be treated. Broad-based aneurysms, which could previously only be treated by surgery, can now be treated by the so-called balloon remodeling technique or stent-assisted coiling, whereby a balloon or stent is placed in the parent vessel to act as a scaffold for the coil. The results of the ISAT study demonstrated that a better outcome for patients could be achieved by endovascular treatment of aneurysms than by neurosurgical clipping of ruptured aneurysms. For this reason the first option should be endovascular treatment when possible. Asymptomatic aneurysms are being observed increasingly more often and primary treatment should be endovascular when possible. The somewhat higher re-bleeding rate for endovascular treatment could not diminish the better results of the ISAT study even during the 5-year follow-up.

Extended follow-up of unruptured intracranial aneurysms detected by presymptomatic screening in patients with autosomal dominant polycystic kidney disease

BACKGROUND AND OBJECTIVES

Autosomal dominant polycystic kidney disease (ADPKD) patients have an increased risk for intracranial aneurysms (IAs). The importance of screening for unruptured IAs (UIAs) depends on their risks for growth and rupture.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

ADPKD patients with UIAs found by presymptomatic screening with magnetic resonance angiography (MRA) during 1989 to 2009 were followed initially at 6 months and annually, and less frequently after demonstration of stability.

RESULTS

Forty-five saccular aneurysms were detected in 38 patients from 36 families. Most were small (median diameter 3.5 mm) and in the anterior circulation (84%). Median age at diagnosis was 49 years. During cumulative imaging follow-up of 243 years, one de novo UIA was detected and increased in size from 2 to 4.4 mm over 144 months and two UIAs grew from 4.5 to 5.9 mm and 4.7 to 6.2 mm after 69 and 184 months, respectively. Seven patients did not have imaging follow-up. No change was detected in the remaining 28 patients. During cumulative clinical follow-up of 316 years, no aneurysm ruptured. Five patients died from unrelated causes and two were lost to follow-up after 8 and 120 months. Three patients underwent surgical clipping.

CONCLUSIONS

Most UIAs detected by presymptomatic screening in ADPKD patients are small and in the anterior circulation. Growth and rupture risks are not higher than those of UIAs in the general population. These data support very selective screening for UIAs in ADPKD patients, and widespread screening is not indicated.

Long-term MRI findings of patients with embolized cerebral aneurysms

BACKGROUND

Long-term follow-up studies after endovascular treatment for intracranial aneurysm are still rare and inconclusive. Parenchymal infarctions related to aneurysms have mostly been studied in patients with subarachnoidal hemorrhage (SAH) but infarction rates in patients with endovascularly treated unruptured aneurysms have been little studied.

PURPOSE

To determine the frequency of permanent parenchymal lesions as detected in magnetic resonance imaging (MRI) in patients treated with endovascular coiling and to assess aneurysm-related infarctions after the initial treatment period.

MATERIAL AND METHODS

A total of 64 patients (32 with primarily ruptured aneurysms) with 69 embolized aneurysms were examined neurologically and by MRI and magnetic resonance angiography (MRA) more than 9 years after the initial endovascular treatment.

RESULTS

A total of 14 out of 32 (44%) SAH patients and 11 (34%) patients with unruptured aneurysms had parenchymal lesions in MRI. Infarctions were detected in 10 (31%) SAH patients and the majority (9/10, 90%) of them were aneurysm-related. All aneurysm-related infarctions were detected at the acute hospitalization stage. A total of six (55%) out of 11 infarctions in patients with unruptured aneurysms were aneurysm-related and two of them appeared after the treatment period. Patients with infarction had poorer clinical outcome than patients with no ischemic lesions in MRI.

CONCLUSION

Nineteen percent of patients with unruptured and 41% with ruptured aneurysms had aneurysm-related parenchymal lesions in MRI. Most of these were detected during acute treatment period. Aneurysm-related infarctions after treatment period are uncommon.

Hospital mortality and complications of electively clipped or coiled unruptured intracranial aneurysm

BACKGROUND AND PURPOSE

To determine the hospital mortality rates associated with elective surgical clipping and endovascular coiling of unruptured intracranial aneurysms.

METHODS

We identified a cohort of patients electively admitted to US hospitals with the diagnosis of unruptured intracranial aneurysm from the National Inpatient Sample database for the years 2000 through 2006. Patient demographics, hospital-associated complications, and in-hospital mortality were compared among the treatment groups. A multivariate logistic regression analysis was used to identify independent variables associated with hospital mortality. Cochrane-Armitage test was used to assess the trend of hospital use of these procedures.

RESULTS

After data cleansing, 3738 (34.3%) patients had aneurysm clipping and 3498 (32.1%) had endovascular coiling. The basic demographics including age, race, and comorbidity indices were similar between the groups. The length of hospital stay was longer in the clipped population (median 4 versus 1 day; P<0.0001), incurring a higher hospital charge in the coiled population (median $42 070 versus $38 166; P<0.0001). Hospital mortality was higher in the clipped population: 60 (1.6%) versus 20 (0.57%; adjusted odds ratio 3.63; 95% CI, 1.57, 8.42). Perioperative intracerebral hemorrhage and acute ischemic stroke were higher in the clipped population. The rate of hospital use of the endovascular coiling has increased over the years included in this study (<0.0001).

CONCLUSIONS

Elective coiling of unruptured intracranial aneurysms is associated with fewer deaths and perioperative complications compared with elective clipping. The trend of hospital use of the coiling procedures has increased during recent years.

Immediate anatomic results after the endovascular treatment of unruptured intracranial aneurysms: analysis of the ATENA series

BACKGROUND AND PURPOSE

A precise analysis of the immediate postoperative anatomic results in a large series of unruptured intracranial aneurysms treated by endovascular approach has not previously been presented. This study aimed to assess the efficacy of endovascular treatment of unruptured intracranial aneurysms in light of immediate postoperative anatomic results in a prospective, multicenter study (the Analysis of Treatment by Endovascular Approach of Nonruptured Aneurysms study; ATENA).

MATERIALS AND METHODS

Postoperative anatomic results from digital subtraction angiography (DSA) were evaluated with the Montreal scale by the treating physician and by 2 anonymous, independent, experienced neuroradiologists.

RESULTS

The analysis included 622 patients (449 women, 173 men; age range, 22-83 years; mean age, 51.2 +/- 11.3 years) harboring 694 aneurysms. Evaluation of the postoperative anatomic results by the 2 independent reviewers indicated total occlusions in 437 aneurysms (63.0%), neck remnants in 156 aneurysms (22.5%), and aneurysm remnants in 101 aneurysms (14.6%). Several factors favorably affected the quality of the aneurysm occlusion with treatment, including patient age (< 65 years old; P < .0001), aneurysm diameter (<or= 6 mm; P = .0049), aneurysm dome-to-neck ratio (> 1.5; P = .0388), and endovascular technique (coiling or remodelling compared with stent placement; P = .0001).

CONCLUSIONS

The endovascular treatment of unruptured aneurysms provided satisfactory postoperative occlusion rates, with a high percentage of complete occlusion or neck remnants (85.4%). Postoperative anatomic results were significantly affected by aneurysm size and neck size, but not aneurysm location.

MR angiographic follow-up of intracranial aneurysms treated with detachable coils: evaluation of a blood-pool contrast medium

BACKGROUND AND PURPOSE

Blood-pool agents are promising in the imaging of small vessels with slow or complex flow. Our aim was to compare blood-pool contrast-enhanced MR angiography (BPCE-MRA) using gadofosveset trisodium (Vasovist) with 3D time-of-flight MRA (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular therapy.

MATERIALS AND METHODS

We included 32 patients with a total of 37 coiled aneurysms. MRAs in the early steady-state phase were performed on a 1.5T scanner within 8 days of digital subtraction angiography (DSA). Two radiologists independently analyzed TOF-MRA and BPCE-MRA images. Consensus was reached by review involving a third neuroradiologist. DSA images were interpreted separately by an interventional radiologist. Findings were assigned to 1 of 3 categories: 1) complete occlusion, 2) residual neck, and 3) residual aneurysm.

RESULTS

Follow-up DSA demonstrated 13 complete obliterations (class 1), 13 residual necks (class 2), and 11 residual aneurysms (class 3). Weighted kappa statistics showed substantial concordance of TOF-MRA and DSA (0.664) as well as BPCE-MRA and DSA (0.724) ratings. Comparison between TOF-MRA and BPCE-MRA found excellent agreement (0.818) with only 6 (16.2%) discrepancies. For detecting residual flow, the difference in accuracy of both MRA techniques (83.8% versus 91.9%) was not significant (McNemar, P = 1.000). BPCE-MRA showed a tendency towards higher sensitivity and specificity (91.7% and 92.3%, respectively) compared with TOF-MRA (87.5% and 76.9%).

CONCLUSIONS

In classifying the completeness of endovascular cerebral aneurysm therapy, we found that BPCE-MRA and 3D TOF-MRA showed very good agreement. The use of Vasovist did not lead to a significantly increased accuracy of MRA follow-up.

Coiling of intracranial aneurysms: a systematic review on initial occlusion and reopening and retreatment rates

BACKGROUND AND PURPOSE

The proportion of incompletely occluded aneurysms after coiling varies widely between studies. To assess overall outcome of coiling, we systematically reviewed the literature to determine initial occlusion, reopening, and retreatment rates of coiled aneurysms according to predefined criteria and subgroups.

METHODS

We searched PubMed and EMBASE (January 1999 to September 2008) for studies of >50 coiled aneurysms. Two reviewers independently extracted data. We grouped studies reporting on only ruptured aneurysms, posterior circulation aneurysms, and studies with large proportions of aneurysms >10 mm to assess possible determinants for incomplete occlusion, reopening, and retreatment.

RESULTS

Forty-six studies totalling 8161 coiled aneurysms met inclusion criteria. Immediately after coiling, 91.2% (95% CI, 90.6% to 91.9%) of the aneurysms were adequately occluded. Aneurysm reopening occurred in 20.8% (95% CI, 19.8% to 21.9%) and retreatment was performed in 10.3% (95% CI, 9.5% to 11.0%). Reopening rate was lower in studies reporting on ruptured aneurysms only compared with all studies (11.4% versus 20.8%; relative risk, 0.55; 95% CI, 0.47 to 0.64) and higher in studies focusing on posterior circulation aneurysms compared with studies with >85% anterior circulation aneurysms (22.5% versus 15.5%; relative risk, 1.5; 95% CI,1.2 to 1.7). Regression analysis showed higher retreatment rates with increasing proportion of aneurysms >10 mm (beta=0.252; 95% CI, 0.073 to 0.432). We could not find a relation between reopening and type of coils used.

CONCLUSIONS

At follow-up, one fifth of all coiled intracranial aneurysms shows reopening of which half is retreated. Possible risk factors for aneurysm reopening are location in the posterior circulation and size >10 mm. To confirm our findings, a meta-analysis on individual well-reported patient data is desirable.

Endovascular occlusion of intracranial wide-necked aneurysms with stenting (Neuroform) and coiling: mid-term and long-term results

INTRODUCTION

Coiling associated with placement of self-expandable intracranial stents has amplified the treatment of intracranial wide-necked aneurysms, but the durability of this treatment and the existence of delayed recurrence are not yet well known. The purpose of this report is to present our experience with the Neuroform Stent associated with coiling and to evaluate complications, effectiveness, and long-term results of this technique.

METHODS

A retrospective study of 42 patients with wide-necked cerebral aneurysms treated with the Neuroform Stent was performed. Mean aneurysm size was 11.3 mm. Mean neck size was 5.33 mm. All patients were treated with coiling and stenting. Clinical and angiographic follow-up was available in 38 patients (90.5%). The overall follow-up time ranged from 6 months to 5 years (mean, 42 months), but most of the patients (92%) had a follow-up period superior to 1 year.

RESULTS

Successful deployment of 41 stents (97%) was obtained. Permanent procedural morbidity was observed in only one patient (2.4%). Long-term complete aneurysmal occlusion was obtained in 27 patients (71%). Aneurysmal regrowth was observed in four patients (9.5%) on the first control angiogram. After the first control angiogram, no delayed recanalization or regrowth was observed. During the follow-up period, there were no hemorrhagic events, no delayed thrombosis, and no stent displacement.

CONCLUSION

Our results demonstrate the effectiveness of the technique, a small rate of procedural complications, and long-term tolerance of the Neuroform Stent. Despite some evidence of early aneurysmal recurrence, long-term durability of stent-assisted aneurysm occlusion is stable after the first year.

Treatment of unruptured intracranial aneurysms: surgery, coiling, or nothing?

The decision of whether and how to treat an unruptured intracranial aneurysm (UIA) is complex. The goal in caring for patients with UIAs is to maximize their duration of high-quality life by optimally balancing the risks of aneurysm rupture--the "natural history" of the aneurysm--with those of treatment-related adverse outcomes. In this article, we review the literature concerning the natural history of UIAs and summarize the procedure-associated morbidity and mortality and efficacy of surgical clipping and endovascular coiling. Using this information, we make recommendations regarding the optimal management of patients with UIAs.