Surgical treatment of unruptured intracranial middle cerebral artery aneurysms: angiographic and clinical outcomes in 143 aneurysms

Clipping first policy for middle cerebral artery aneurysm: A single-center cohort study

Background

The management choice for the middle cerebral artery aneurysms (MCAAs) is still controversial. This review aims to describe a single-center "clipping first" policy for MCAA over 40 years of experience and compare the short- and long-term clinical outcomes by aneurysm's location.

Methods

This retrospective cohort study reviews the whole series of a single-center intracranial aneurysm mainly based on the micro-neurosurgical experience of the senior authors (EOA and EKA). More than 968 aneurysm patients were treated at the University Hospital "Hôpital des Spécialités" Ibn Sina of Rabat in Morocco since 1983. We have included aneurysmal subarachnoid hemorrhage patients with the World Federation of Neurosurgical Societies (WFNS) Grade ≤III (64.7% clipped; 6.9% coiled) and those with WFNS Grade ≥IV (27.5% clipped; 0.9% coiled).

Results

From the database of 1069 IAs in 968 patients, we depicted 218 (22.5%) patients carrying 279 (26.1%) MCAA. About 92.1% (n = 257) of the MCAAs were microsurgically clipped, and 96.3% (n = 210) were discharged with good outcomes (modified Rankin Scale [mRS] ≤2). In the post hoc test, the mean of intracerebral hemorrhage (ICH) (4.178) among the group of poor outcome patients (mRS >2) was significantly (P = 0.001) high compared to that of 0.827 good outcome patients (mRS ≤2). The negative correlation found between the dome/neck ratio and the mRS (Pearson's r = -0.023, 95%confidence interval [CI] 0.110--0.156) at admission (Pearson's r = -0.073, 95%CI 0.061--0.204) and at discharge confirmed that the wider the MCAA neck is, the more susceptible it is to have a poor prognosis.

Conclusion

The good clinical outcome from the microsurgically clipped patients is overwhelming and allows us to conclude that microsurgical treatment should be mostly considered for MCAA management. The patient's poor outcome with MCAA at discharge was significantly associated with ICH at admission in the frequency of 68.9%.

Development of a predictive grading system for postoperative ischemia following middle cerebral artery aneurysm clipping

The current study presents a single-surgeon experience with microsurgical clipping of middle cerebral artery (MCA) aneurysms and introduces a grading system to predict postoperative ischaemia. A retrospective analysis of 222 patients with 251 MCA aneurysms treated between 2015 and 2024 was conducted. Key factors, including aneurysm size, dome morphology, neck location, calcification, and rupture status, were evaluated to identify predictors of radiological infarction. A scoring model was developed, assigning points for aneurysm neck distance from the internal carotid artery (>20 mm: 1 point; 10-20 mm: 2 points; <10 mm: 3 points), aneurysm size > 7 mm (1 point), calcification (1 point), and rupture status (1 point). The grading system demonstrated a significant risk gradient, with infarction rates of 0 %, 3 %, 11 %, 35 %, and 83 % for grades 1 to 5, respectively (p < 0.0001). Independent predictors of poor outcomes were identified as a short M1 segment (p = 0.002), aneurysm size > 7 mm (p = 0.019), calcification (p < 0.001), and rupture presentation (p = 0.002). Postoperative ischaemia occurred in 7 patients (23 %) with ruptured aneurysms and 18 patients (9 %) with unruptured aneurysms. This grading system provides a practical tool for stratifying risk and guiding treatment decisions. Further multi-centre studies are needed to validate its broader applicability.

Microsurgical Clipping of Unruptured Middle Cerebral Artery Bifurcation Aneurysms: A Single-Center Experience

BACKGROUND/OBJECTIVES

Microsurgical clipping has traditionally been considered a standard treatment for middle cerebral artery (MCA) aneurysms. Recently, a caseload reduction related to improved endovascular treatment options has occurred in cerebrovascular neurosurgery. Therefore, studies that report the clinical and radiological outcomes after clipping are highly warranted.

METHODS

Patients with an unruptured MCA bifurcation aneurysm, who were surgically treated at the Department of Neurosurgery in Linz between 2002 and 2019, were included in this study. Clinical and radiological outcome parameters were evaluated for each patient.

RESULTS

Overall, 272 patients were eligible for inclusion. Complete aneurysm occlusion was demonstrated in 266 (99.3%) of the 268 (98.5%) patients who underwent postoperative digital subtraction angiography. In six (2.2%) patients, a permanent new neurological deficit (pNND) persisted after treatment. Intraoperative aneurysm rupture was a significant factor (p = 0.0049) in the logistic regression. At the last follow-up, only two patients (0.7%) had an unfavorable outcome (mRS > 2). More recent surgeries were associated with fewer cases of pNND (p = 0.009). A transient new neurological deficit occurred in 13 patients (4.8%), with aneurysm size being a significant risk factor (p = 0.009). Surgical site infections were reported in four patients (1.5%), with patient age (p = 0.039) and time (p = 0.001) being significant factors. Two patients died (0.7%) perioperatively and two patients (0.7%) needed a retreatment in the long-term follow-up.

CONCLUSIONS

The findings indicate that microsurgical clipping is a safe procedure with minimal need for retreatment. It achieves a high occlusion rate while maintaining a very low rate of adverse outcomes. Continuous intraoperative enhancements over time have contributed to a progressive improvement in clinical outcomes in recent years. This trend is exemplified by the absence of detectable pNND in the era of ICG angiography. Consequently, these data support the conclusion that microsurgical clipping should still be considered an appropriate treatment option for unruptured MCA bifurcation aneurysms.

Open Surgical Treatment of Middle Cerebral Artery Aneurysms: A Single-Center Series in the Endovascular Era

OBJECTIVE

We review the outcomes of open surgical treatment of middle cerebral artery aneurysms (MCAAs) at a single center, focusing on aneurysm obliteration rates and functional outcomes at the most recent follow-up. These findings can be used for future comparisons of surgical outcomes with MCAAs.

METHODS

We retrospectively reviewed cases from a prospectively maintained database of patients receiving open surgical treatment for ruptured or unruptured MCAAs between July 2014 and December 2022. We utilized patients' modified Rankin Scale (mRS) score and Glasgow Outcome Scale score as functional outcome measures. Means, standard deviations, medians, and interquartile ranges were calculated, and a student's t test or its nonparametric equivalent was used to compare subgroups.

RESULTS

One hundred fifty patients (114 women, 76%; mean age 55.0 ± 14.7 years) with a total of 156 MCAAs comprised 152 cases; 85 (56%) ruptured and 71 (46%) unruptured. Bypass was performed in 34 cases (22.4%); 18 ruptured (51.4%) and 16 unruptured (48.6%). Intraoperative rupture occurred in 5 (5%) ruptured and 1 (2%) unruptured cases. Onwe hundred forty-five patients (95.4%) had aneurysm obliteration with initial surgery, with 98.4% of patients having complete occlusion at 40.2± 65.5 weeks of follow-up. Intrahospital mortality occurred in 7 (6.9%) ruptured versus 1 (2.0%) unruptured case. Fifty-two (51.5%) of the ruptured compared to 43 (86%) unruptured patients were discharged home, with the remaining patients requiring inpatient rehabilitation or long-term hospitalization. The ruptured group had a mean hospital stay of 18.4 ± 10.5 days versus. 5.7 ± 6.0 days for unruptured. Length of stay, discharge mRS/ Glasgow Outcome Scale, and mRS at 4-6 weeks favored unruptured cases (P < 0.0001-0.0336). Mean change in mRS from presentation to last follow-up favored ruptured cases (-0.7 ± 1.2 vs. -0.04 ± 1.2, P = 0.0215).

CONCLUSIONS

Open surgery remains a safe and definitive treatment option for MCAAs in the endovascular era.

Safety and efficacy of the flow diverter device for treating middle cerebral artery aneurysms of the proximal (M1) segment related to the lenticulostriate arteries: A single-center experience

BACKGROUND

Experience using flow diverter devices (FDDs) to treat proximal (M1) middle cerebral artery aneurysms associated with the lenticulostriate artery (M1A-LA) remains limited. This study aimed to examine the efficacy and safety of an FDD to manage M1A-LA.

METHOD

Patients with M1A-LA who received FDD treatment at a single center were included in the analysis. Data on the baseline characteristics, postoperative conditions, and follow-up results of the participants were recorded and analyzed. The aneurysms were categorized into three subtypes based on morphology and location. Aneurysms confined to the M1 segment were categorized as subtype A. Those extending to the M2 segment were classified as subtype B. Aneurysms designated as subtype C were confined to the M1 segment but with another independent aneurysm in the distal artery and the presence of healthy vessels between the two. Subgroup analyses were conducted on these subtypes and aneurysm sizes. To assess the consistency of follow-up results, Cronbach's kappa/alpha was used to calculate inter-rater variability. Somers's D coefficient was used to assess the correlation between each subgroup and the imaging outcomes; Fisher's exact test was used to compare the variability among the subgroups.

RESULT

The cohort comprised 11 patients. Their Modified Rankin Scale scores between the perioperative and follow-up periods did not differ. During the follow-up period, four patients had completely occluded aneurysms, and five patients had partial occlusions. The remaining patients did not present with changes in their aneurysms. The kappa coefficient was 0.864 (p < 0.001). M1A-LA was divided into subtypes A, B, and C. Subtype A (defined as an aneurysm completely located in the M1 segment) had a higher complete occlusion rate than that of subtypes B and C, Somers's D R/C correlation coefficient was 0.553, with a 95% confidence interval of 0.1229-0.9823 (p = 0.009). The radiographic follow-up findings were not significantly correlated with the size of the aneurysm (p = 0.121) or the use of coiling (p = 0.903). No significant differences in subtypes (p = 0.264), aneurysm size (p = 0.657), or coiling use (p > 0.999) were observed.

CONCLUSION

FDDs were safe and possibly effective against M1A-LA. However, they were not as effective as for intracranial aneurysms in other locations. FDDs are a satisfactory treatment option for M1A-LA, particularly for subtype A aneurysms.

Meningitis after elective intracranial surgery: a systematic review and meta-analysis of prevalence

Meningitis is a potential complication of elective intracranial surgery (EIS). The prevalence of meningitis after EIS varies greatly in the literature. The objective of this study was to estimate the overall pooled prevalence of meningitis following EIS. Four databases (PubMed, Scopus, Web of Science, and Embase) were searched to identify relevant studies. Meta-analyses of proportions were used to combine data. Cochran's Q and I2 statistics were used to assess and quantify heterogeneity. Additionally, several subgroup analyses were conducted to investigate the source of heterogeneity and examine differences in the prevalence based on variables such as geographical regions, income level, and meningitis type. The meta-analysis included 83 studies (30 959 patients) from 26 countries. The overall pooled prevalence of meningitis after EIS was 1.6% (95% CI 1.1-2.1), with high heterogeneity present (I2 = 88%). The pooled prevalence in low- to middle-income countries and high-income countries was 2.7% (95% CI 1.6-4.1) and 1.2% (95% CI 0.8-1.7), respectively. Studies that reported only aseptic meningitis had a pooled prevalence of 3.2% (95% CI 1.3-5.8). The pooled prevalence was 2.8% (95% CI 1.5-4.5) in studies that reported only bacterial meningitis. Similar prevalence rates of meningitis were observed in the subgroups of tumor resection, microvascular decompression, and aneurysm clipping. Meningitis is a rare but not exceptional complication following EIS, with an estimated prevalence of 1.6%.

Noncurative microsurgery for cerebral aneurysms: a systematic review and meta-analysis of wrapping, residual, and recurrence rates

OBJECTIVE

Microsurgery for cerebral aneurysms is called definitive, yet some patients undergo a craniotomy that results in noncurative treatment. Furthermore, the overall rate of noncurative microsurgery for cerebral aneurysms is unclear. The objective of this study was to complete a systematic review and meta-analysis to quantify three scenarios of noncurative treatment: aneurysm wrapping, postclipping remnants, and late regrowth of completely obliterated aneurysms.

METHODS

A PRISMA-guided systematic literature review of the MEDLINE and Cochrane Library databases and meta-analysis was completed. Studies were included that detailed rates of aneurysm wrapping, residua confirmed with imaging, and regrowth after confirmed total occlusion. Pooled rates were subsequently calculated using a random-effects model. An assessment of statistical heterogeneity and publication bias among the included studies was also completed for each analysis, with resultant I2 values and p values determined with Egger's test.

RESULTS

Sixty-four studies met the inclusion criteria for final analysis. In 41 studies, 573/15,715 aneurysms were wrapped, for a rate of 3.5% (95% CI 2.7%-4.2%, I2 = 88%). In 43 studies, 906/13,902 aneurysms had residual neck or dome filling, for a rate of 6.4% (95% CI 5.2%-7.6%, I2 = 93%). In 15 studies, 71/2568 originally fully occluded aneurysms showed regrowth, for a rate of 2.1% (95% CI 1.2%-3.1%, I2 = 58%). Together, there was a total rate of noncurative surgery of 12.0% (95% CI 11.5%-12.5%). Egger's test suggested no significant publication bias among the studies. Meta-regression analysis revealed that the reported rate of aneurysm wrapping has significantly declined over time, whereas the rates of aneurysm residua and recurrence have not significantly changed.

CONCLUSIONS

Open microsurgery for cerebral aneurysm results in noncurative treatment approximately 12% of the time. This metric may be used to counsel patients and as a benchmark for other treatment modalities. This investigation is limited by the high degree of heterogeneity among the included studies.

Frequency and risk factors for postoperative aneurysm residual after microsurgical clipping

OBJECTIVE

Aneurysm residuals after clipping are a well-known problem, but the course of aneurysm remnants in follow-up is not well studied. No standards or follow-up guidelines exist for treatment of aneurysm remnants. The aim of this study was to evaluate the risk factors for postoperative aneurysm remnants and their changes during follow-up.

METHODS

We performed a retrospective analysis of 666 aneurysms treated via clipping in our hospital from 2006 to 2016. Postoperative and follow-up angiographic data were analyzed for aneurysm remnants and regrowth. Clinical parameters and aneurysm-specific characteristics were correlated with radiological results.

RESULTS

The frequency of aneurysm residuals was 12% (78/666). Aneurysms located in the middle cerebral artery (p = 0.02) showed a significantly lower risk for incomplete aneurysm occlusion. Larger aneurysms with a diameter of 11-25 mm (p = 0.005) showed a significantly higher risk for incomplete aneurysm occlusion. Five patients underwent re-clipping during the same hospital stay. Remnants were stratified based on morphological characteristics into "dog ears" (n = 60) and "broad based" (n = 13). The majority of the "dog ears" stayed stable, decreased in size, or vanished during follow-up. Broad-based remnants showed a higher risk of regrowth.

CONCLUSIONS

A middle cerebral artery location seems to lower the risk for the incomplete clip occlusion of an aneurysm. Greater aneurysm size (11-25 mm) is associated with a postoperative aneurysm remnant. The majority of "dog-ear" remnants appear to remain stable during follow-up. In these cases, unnecessarily frequent angiographic checks could be avoided. By contrast, broad-based residuals show a higher risk of regrowth that requires close imaging controls if retreatment cannot be performed immediately.

Endovascular Treatment for Middle Cerebral Artery Aneurysms: Single-Center Experience and Review of Literatures

Objective

The efficacy of endovascular treatment for middle cerebral artery (MCA) aneurysms remains controversial. However, recent studies have reported the safety of endovascular treatment for MCA aneurysms. In this study, we studied the efficacy and clinical outcomes of endovascular treatment for MCA aneurysms in our hospital and the morphology and anatomy of MCA aneurysms that were suitable for endovascular treatment.

Methods

We retrospectively analyzed 26 cases of MCA aneurysms which had undergone endovascular treatment at our institution between January 2015 and October 2018. We studied sizes and shapes of the aneurysms, clinical and angiographical outcomes one year after the treatment, and complications in these 26 patients. We also compared the differences in these parameters of the 26 patients with those of 61 other patients who were treated with clipping during the same period.

Results

The median aneurysm size was 6.1 mm (1.8-29.9 mm), with the shapes of the aneurysms irregular in 8, and round in the other 18 cases. Four cases (15.4%) had ruptured aneurysms. All aneurysms were treated with assist techniques; 8 (30.8%) were treated by stent-assisted technique and 18 (69.2%) were treated by balloon-assisted technique and endovascular treatment was successfully performed in all (100%) cases. While the aneurysms were completely obliterated in 22 of them (84.6%), the remaining 4 cases (15.4%) had neck remnants. We observed periprocedural complications in 5 of the 26 (19.2%) aneurysms, all of which were transient and completely recovered during the follow-up period. The efficacy and complication rates were not different from the MCA aneurysms treated with clipping. All MCA aneurysms arising from the M1 trunk were treated with endovascular treatment, and those with a round shape with the axis not deviating from M1 were also treated with endovascular treatment.

Conclusion

Endovascular treatment for MCA aneurysms is safe and effective together with adjunctive techniques such as balloon-assisted technique or stent-assisted technique. Thus, M1 trunk aneurysms and MCA bifurcation aneurysms with a round shape along the same axis of MCA may be good indications for endovascular treatment. However, long-term clinical and angiographical outcomes remain unknown. Thus, further studies are needed to address the existing limitations.

Identifying Predictors for Aneurysm Remnants After Clipping by Morphometric Analysis and Proposal of a Novel Risk Score

OBJECTIVE

Although the risk of aneurysm remnants after microsurgical clipping is generally low, complete aneurysm occlusion is not always guaranteed. We performed a morphometric analysis of intracranial aneurysms to identify predictors for aneurysm remnants and to propose a novel risk score.

METHODS

This is a retrospective, single-center analysis of consecutive patients with ruptured and unruptured aneurysms who underwent microsurgical clipping and postoperative digital subtraction angiography between 2010 and 2018. Based on preoperative rotational angiography, distinct morphologic aneurysm characteristics were determined and correlated with postoperative angiographic results. Factors predictive in the univariate and multivariate analyses were determined to establish a risk score for postoperative remnants after aneurysm clipping.

RESULTS

Among 140 patients with 166 clipped aneurysms, aneurysm remnants were present in 19.9%. In the multivariate analysis, ruptured aneurysm status (odds ratio [OR], 7.8; 95% confidence interval [CI], 1.7-36; P < 0.01) and increased aspect ratio (OR, 1.9; 95% CI, 1.0-4.0; P = 0.07) were associated with postoperative aneurysm remnants. Anterior communicating artery location (P = 0.02), internal carotid artery location (P = 0.06), increased aneurysm inclination angle (P < 0.01), and irregular aneurysm shape (P = 0.07) were further predictors for aneurysm remnants in the univariate analysis. These factors were weighted and included into a risk sum score for postoperative aneurysm remnants (range, 0-8 points), which performed with good accuracy (area under the curve = 0.807).

CONCLUSIONS

After external validation of the proposed risk score, it could help identify cases requiring angiographic control after aneurysm surgery.

Microsurgical treatment of unruptured middle cerebral artery aneurysms: a large, contemporary experience

OBJECTIVE

Advances in endovascular therapy for the treatment of middle cerebral artery (MCA) aneurysms have led to scrutiny of its benefits compared with microsurgical repair. To provide information regarding complication rates and outcomes, the authors reviewed the results of a large series of unruptured MCA aneurysms treated with open microsurgery.

METHODS

The authors included all patients who underwent surgical repair of an unruptured MCA aneurysm between 1997 and 2015. All surgical procedures, including clipping, wrapping, bypass, and parent artery occlusion, were performed by a single neurosurgeon. Aneurysm occlusion was assessed using intraoperative digital subtraction angiography (DSA) or DSA and indocyanine green videoangiography in all cases. Postoperatively, all patients were monitored in a neurointensive care unit overnight. Clinical follow-up was scheduled for 2-4 weeks after surgery, and angiographic follow-up was performed in those patients with subtotally occluded aneurysms at 1, 2, and 5 years postoperation.

RESULTS

The authors treated 750 unruptured MCA aneurysms in 716 patients: 649 (86.5%) aneurysms were small, 75 (10.0%) were large, and 26 (3.5%) were giant. Most aneurysms (n = 677, 90%) were treated by primary clip reconstruction. The surgical morbidity rate was 2.8%, and the mortality rate was 0%. Complete angiographic aneurysm occlusion was achieved in 92.0% of aneurysms. At final follow-up, 713 patients had a modified Rankin Scale (mRS) score of 0, 2 patients had an mRS score of 2 or 3, and 1 had an mRS score of 4.

CONCLUSIONS

In high-volume centers, microsurgical management of MCA aneurysms can be performed with very low morbidity rates. Currently, microsurgical repair appears to be a highly effective method of treating MCA aneurysms.

Proximal Middle Cerebral Artery Aneurysms: Microsurgical Management and Therapeutic Results

BACKGROUND

Management of proximal (M1) middle cerebral artery (MCA) aneurysms can be challenging. Because of the diversity of aneurysm morphology and location of M1 aneurysms, the surgical strategy should be tailored to each individual case, especially for complex cases. We assessed the safety and efficacy of an algorithmic strategy for the management of M1 aneurysms.

METHODS

A prospective single-center study of M1 aneurysms treated with microsurgery was performed. Our algorithmic strategy was determined by the location and complexity (e.g., size, shape) of the aneurysms. The surgical modalities included neck clipping, aneurysm resection and/or trapping, and proximal occlusion with revascularization. The clinical and radiographic data were analyzed.

RESULTS

From January 2007 to March 2017, 92 proximal MCA aneurysms in 92 patients were treated microsurgically. Aneurysm treatment techniques included clipping in 55, proximal occlusion in 21, aneurysm resection in 11, and trapping in 4. Bypass techniques included 2 anterior temporal artery reconstructions, 5 middle cerebral bifurcation reconstructions, 4 parent artery reanastomoses, 2 interpositional bypasses, 25 high-flow bypasses, and 7 medium-flow bypasses. Overall, good outcomes (modified Rankin scale score, 0-2) were seen in 49 of 92 patients (53.3%) at discharge and in 79 of 91 (86.8%) at the last follow-up visit. On the latest angiogram, 78 of 90 aneurysms (86.7%) had been completely occluded without a remnant. Bypass patency was confirmed in 38 of 43 bypass procedures.

CONCLUSIONS

Our present treating strategy might provide a benefit for patients with proximal MCA aneurysms.

Residual Cerebral Aneurysms After Microsurgical Clipping: A New Scale, an Agreement Study, and a Systematic Review of the Literature

OBJECTIVE

The surgical repair of a cerebral aneurysm does not always lead to complete occlusion. A standardized repeatable method of reporting results of surgical clipping is desirable. Our purpose was to systematically review methods of classifying aneurysm remnants, provide a new scale with precise definitions of categories, and perform an agreement study to assess the variability in adjudicating remnants after aneurysm clipping.

METHODS

A systematic review was performed to identify ways to report angiographic results of surgical clipping between 1963 and 2017. Postclipping angiographic results of 43 patients were also independently evaluated by 10 raters of various experience and backgrounds using a new 4-category scale. Agreement between responses were analyzed using κ statistics.

RESULTS

The systematic review yielded 63 articles with 37 different nomenclatures using 2-6 categories. The reliability of judging the presence of an aneurysm remnant on catheter angiography was studied only twice, with only 2 raters each time, with contradictory results. Interobserver agreement using the new 4-category scale was moderate (κ = 0.52; 95% confidence interval, 0.43-0.62) for all observers, but improved to substantial (κ = 0.62; 95% confidence interval, 0.47-0.76) when results were dichotomized (grade 0/1 vs. 2/3).

CONCLUSIONS

Various classification schemes to evaluate angiographic results after surgical clipping exist in the literature, but they lack standardization. Adjudication using fewer, better defined categories may yield more reliable agreement.

Coiling Versus Microsurgical Clipping in the Treatment of Unruptured Middle Cerebral Artery Aneurysms: A Meta-Analysis

BACKGROUND

Open microsurgical clipping of unruptured intracranial aneurysms has long been the gold standard, yet advancements in endovascular coiling techniques have begun to challenge the status quo.

OBJECTIVE

To compare endovascular coiling with microsurgical clipping among adults with unruptured middle cerebral artery aneurysms (MCAA) by conducting a meta-analysis.

METHODS

A systematic search was conducted from January 2011 to October 2015 to update a previous meta-analysis. All studies that reported unruptured MCAA in adults treated by microsurgical clipping or endovascular coiling were included and cumulatively analyzed.

RESULTS

Thirty-seven studies including 3352 patients were included. Using the random-effects model, pooled analysis of 11 studies of microsurgical clipping (626 aneurysms) revealed complete aneurysmal obliteration in 94.2% of cases (95% confidence interval [CI] 87.6%-97.4%). The analysis of 18 studies of endovascular coiling (759 aneurysms) revealed complete obliteration in 53.2% of cases (95% CI: 45.0%-61.1%). Among clipping studies, 22 assessed neurological outcomes (2404 aneurysms), with favorable outcomes in 97.9% (95% CI: 96.8%-98.6%). Among coiling studies, 22 examined neurological outcomes (826 aneurysms), with favorable outcomes in 95.1% (95% CI: 93.1%-96.5%). Results using the fixed-effect models were not materially different.

CONCLUSION

This updated meta-analysis demonstrates that surgical clipping for unruptured MCAA remains highly safe and efficacious. Endovascular treatment for unruptured MCAAs continues to improve in efficacy and safety; yet, it results in lower rates of occlusion.

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.

Comparison of clipping and coiling in elderly patients with unruptured cerebral aneurysms

OBJECTIVE The comparative effectiveness of the 2 treatment options-surgical clipping and endovascular coiling-for unruptured cerebral aneurysms remains an issue of debate and has not been studied in clinical trials. The authors investigated the association between treatment method for unruptured cerebral aneurysms and outcomes in elderly patients. METHODS The authors performed a cohort study of 100% of Medicare fee-for-service claims data for elderly patients who had treatment for unruptured cerebral aneurysms between 2007 and 2012. To control for measured confounding, the authors used propensity score conditioning and inverse probability weighting with mixed effects to account for clustering at the level of the hospital referral region (HRR). An instrumental variable (regional rates of coiling) analysis was used to control for unmeasured confounding and to create pseudo-randomization on the treatment method. RESULTS During the study period, 8705 patients underwent treatment for unruptured cerebral aneurysms and met the study inclusion criteria. Of these patients, 2585 (29.7%) had surgical clipping and 6120 (70.3%) had endovascular coiling. Instrumental variable analysis demonstrated no difference between coiling and clipping in 1-year postoperative mortality (OR 1.25, 95% CI 0.68-2.31) or 90-day readmission rate (OR 1.04, 95% CI 0.66-1.62). However, clipping was associated with a greater likelihood of discharge to rehabilitation (OR 6.39, 95% CI 3.85-10.59) and 3.6 days longer length of stay (LOS; 95% CI 2.90-4.71). The same associations were present in propensity score-adjusted and inverse probability-weighted models. CONCLUSIONS In a cohort of Medicare patients, there was no difference in mortality and the readmission rate between clipping and coiling of unruptured cerebral aneurysms. Clipping was associated with a higher rate of discharge to a rehabilitation facility and a longer LOS.

Flow Diversion for the Treatment of MCA Bifurcation Aneurysms-A Single Centre Experience

Background

Intracranial aneurysms located at the bifurcation of the middle cerebral artery (MCA) can often be challenging for the neurointerventionalist. We aimed to evaluate the efficacy and safety of flow diverting stents (FDS) in the treatment of these aneurysms.

Materials and methods

We retrospectively reviewed our prospectively maintained database to collect information for all patients with unruptured saccular bifurcation MCA aneurysms treated with FDS between January 2010 and January 2016. In addition to demographic data, we recorded the location, aneurysm characteristics, previous treatments, number and type of FDS, complications, and clinical and angiographic follow-up.

Results

Our search identified 13 patients (7 males) with an average age of 61.7 years (47–74 years). All patients had a single bifurcation aneurysm of the MCA, and none of the aneurysms were acutely ruptured. The average fundus size of the saccular aneurysms was 3 mm (range 1.5–10 mm). Follow-up studies were available for 12 patients. Based on the most recent follow-up angiograms, six aneurysms (50%) were totally occluded; five aneurysms (41.7%) showed only a small remnant; and one aneurysm (8.3%) remained unchanged. One patient suffered from an ischemic stroke with resultant permanent hemiparesis (mRS 3). In another case, there was an in-stent thrombosis during the intervention, which resolved upon intra-arterial infusion of Eptifibatide (mRS 0). There were no intra-operative vessel or aneurysm ruptures and no mortalities. Angiography of the covered MCA branches showed no change in the caliber or flow of the vessel in six (50%), a reduction in caliber in five (41.7%), and a complete occlusion in one (8.3%). All caliber changes and occlusions of the vessels were asymptomatic.

Conclusion

In our series, 91.7% of treated MCA bifurcation aneurysms were either completely occluded or showed only a small remnant with a good safety profile. Flow diversion of MCA bifurcation aneurysms should be considered as an alternative treatment strategy when microsurgical clipping or alternative endovascular treatment options are not feasible.

Treatment of ruptured middle cerebral artery aneurysms by endovascular approach: a single-center experience

PURPOSE

The optimal treatment modalities of ruptured middle cerebral artery aneurysm are still controversial. The objective of this study is to analyze the outcomes of patients with ruptured middle cerebral artery aneurysms treated by endovascular coiling.

MATERIALS AND METHODS

From October 2011 to October 2015, 67 patients with 71 ruptured middle cerebral artery aneurysms received endovascular coiling in our hospital. We retrospectively reviewed the clinical, radiologic records and outcomes.

RESULTS

Of all the 71 aneurysms (67 patients), 42 were treated by coil embolization merely, 27 by stent-assisted coiling and 2 unruptured aneurysms in patients with bilateral middle cerebral artery aneurysms without receiving treatment. Complete occlusion was achieved in 82.6% (57/69) of all the procedures. Each of incomplete and partial occlusion rates was 8.7% (6/69). Intraoperative rupture of aneurysms occurred in two procedures (2.9%). Thrombogenesis occurred in eight procedures (11.6%). Brain infarction occurred in eight patients (11.9%). Post-operative rebleeding occurred in seven patients (10.4%). Sixty-three patients were followed at a mean follow-up of 8.24 ± 7.16 months. The mortality and good outcome rate were 3.2% and 90.5%, respectively. Aneurysm recurrence occurred in 6 (13.3%) of the 45 aneurysms at a mean follow-up of 8.44 ± 7.83 months.

CONCLUSIONS

Endovascular coiling is effective for patients with ruptured middle cerebral artery aneurysms. Individualized treatment should be assessed by experienced specialist. It is essential to perform randomized large trials to confirm the efficiency of endovascular coiling.

"Clip first" policy in management of intracranial MCA aneurysms: Single-centre experience with a systematic review of literature

BACKGROUND

The results of microsurgical treatment for middle cerebral artery (MCA) aneurysms (ANs) have been highly satisfying for decades, notoriously posing a challenge for interventional neuroradiologists. Following the International Subarachnoid Aneurysm Trial (ISAT) study results, most centres across Europe and the USA switched to a "coil first" policy. The purpose of this study is to evaluate and critically review the substantiation of this change.

METHODS

The authors conducted a single-institution retrospective study of MCA AN treatment between January 2000 and December 2013 maintaining a "clip first" policy. The results are supplied with a literature review.

RESULTS

A total of 315 MCA ANs were treated in 288 consecutive patients (209 females, 79 males). Microsurgical treatment was performed for 238 AN patients (116 ruptured, 122 unruptured) and 77 AN patients (46 ruptured, 31 unruptured) who underwent a coiling procedure. Treatment-related morbidity and mortality (MM) for unruptured ANs was 2.8 % in the microsurgical group and 10.3 % in the endovascular group. The percentage of patients with no/minor permanent neurological deficits after SAH in a good initial clinical state (HH 1-2) was 93 % in the microsurgical and 76 % in the endovascular group. A literature review identified 21 studies concerning MCA AN treatment with a specified decision-making algorithm. Microsurgery seemed superior to endovascular management regarding both clinical and radiological outcomes, although several aspects of the analysed reports might appear questionable.

CONCLUSION

Although this study has its inherent limitations, the effect brought about by microsurgical clipping of MCA ANs remains superior to that of endovascular embolisation and it should be sustained as the first treatment choice. The decision about the treatment strategy should be made by a multi-disciplinary team consisting of specialists from both teams, bearing in mind the higher occlusion rate and longevity of the surgical treatment.

Surgical management of ruptured small cerebral aneurysm: Outcome and surgical notes

Background:

Management of small aneurysms often poses a therapeutic dilemma and surgical treatment or coiling can be considered as therapeutic choices. In the present study, we reviewed our series of ruptured small cerebral aneurysm treated surgically.

Methods:

A total of 53 consecutive patients with ruptured small aneurysm were surgically treated between January 2008 and July 2014. Data were retrospectively collected. Procedure-related death and complications were systematically reviewed. Clinical outcomes were assessed using the Modified Ranking Scale. Neuroradiological follow-up was performed to assess aneurysmal occlusion and recanalization rate.

Results:

The mean aneurysm size was 2 mm ± 0.8 mm. All the patients were operated and the aneurysm clipped. Clinical outcomes were as expected on the basis of the presenting Hunt and Hess grade. Overall, major and minor neurological deficit related to clipping were 5.2% and 2.2%, respectively. At the time of discharge, 84.9% of the patients presented with a favorable outcome, while 15.1% had poor clinical outcome. Aneurysm occlusion was achieved in all the cases. Neither recanalization nor re-aneurysmal rupture was observed in the clinical follow-up.

Conclusion:

Aneurysms, 3 mm in diameter or smaller, represent a therapeutic challenge. Given the proven role of microsurgery in small aneurysms and the perceived challenges with endovascular therapy, surgical clipping still can be considered an effective treatment modality in this setting.

New York State: Comparison of Treatment Outcomes for Unruptured Cerebral Aneurysms Using an Instrumental Variable Analysis

Background

There is wide regional variation in the predominant treatment for unruptured cerebral aneurysms. We investigated the association of elective surgical clipping and endovascular coiling with mortality, readmission rate, length of stay, and discharge to rehabilitation.

Methods and Results

We performed a cohort study involving patients with unruptured cerebral aneurysms, who underwent surgical clipping or endovascular coiling from 2009 to 2013 and were registered in the Statewide Planning and Research Cooperative System database. An instrumental variable analysis was used to investigate the association of treatment technique with outcomes. Of the 4643 patients undergoing treatment, 3190 (68.7%) underwent coiling, and 1453 (31.3%) underwent clipping. Using an instrumental variable analysis, we did not identify a difference in inpatient mortality (marginal effect, 0.13; 95% CI, −0.30, 0.57), or the rate of 30-day readmission (marginal effect, −1.84; 95% CI −4.06, −0.37) between the 2 treatment techniques for patients with unruptured cerebral aneurysms. Clipping was associated with a higher rate of discharge to rehabilitation (marginal effect, 2.31; 95% CI 0.21, 4.41), and longer length of stay (β, 2.01; 95% CI 0.85, 3.04). In sensitivity analysis, mixed-effect regression, and propensity score, adjusted regression models demonstrated identical results.

Conclusions

Using a comprehensive all-payer cohort of patients in New York State with unruptured cerebral aneurysms, we did not identify an association of treatment method with mortality or 30-day readmission. Clipping was associated with a higher rate of discharge to rehabilitation and longer length of stay.

Surgical Treatment of Middle Cerebral Artery Aneurysms Without Using Indocyanine Green Videoangiography Assistance: Retrospective Monocentric Study of 263 Clipped Aneurysms

INTRODUCTION

Middle cerebral artery (MCA) aneurysms represent 20% of intracranial aneurysms. Most (80%) of them are located on the sylvian bifurcation, the seat of hemodynamic turbulence flow. Morbidity and mortality related to surgery of MCA aneurysms are not negligible. MCA vascularization areas are important eloquence functional territorial of Brain tissue. Indocyanine green videoangiography assistance (ICG-VA) is an emergent tool for intraoperative assessment of aneurysmal occlusion and for checking a possible stenosant clip in vascular area. The purposes of this study were to evaluate the safety of clipping procedure in terms of morbidity, mortality, and efficiency of aneurysm occlusion without using ICG-VA, recurrence and bleeding/rebleeding at short and long terms, and angiographic and clinical follow-ups.

MATERIAL AND METHODS

This study is a monocentric retrospective study performed at Pitié-Salpêtrière-Charles Foix Hospital Center, reporting clinical and angiographic follow-up of consecutive patients treated for MCA aneurysms (ruptured and unruptured) by clipping procedures. From 2002-2012, 251 consecutive patients were admitted at the author's institution for treatment of 263 MCA aneurysms (163 ruptured and 100 unruptured). Procedure-related death and complications were systematically assessed without video-angiography availability. The degree of aneurysms exclusion was evaluated according to the Raymond-Roy scale after the procedure and at long-term angiographic follow-up (mean delay = 36 months).

RESULTS

The death rate related to aneurysmal exclusion procedure was 1.2%. The major complication rate related to surgery was 5.3%. Postprocedure, an aneurysm occlusion rate Raymond-Roy grade A or B was 95.6%. Neither recanalization controlled clipped aneurysms nor re-aneurysmal rupture was observed in the long-term clinical follow-up (mean time = 83.5 months). The institution's series of surgical outcomes reported 95.6% of complete exclusion and 4.5% incomplete procedures without ICG-VA. A clip of repositioning rate was estimated at 15% when ICG-VA was used.

CONCLUSION

Surgical management is relatively safe for patients, with an acceptable complication rate in the era when ICG-VA was not yet available. Indeed, the main source of procedural ischemia microsurgery is stenosant clip. To limit the occurrence of malposition, the author's center began using ICG-VA a few months ago and expects to reduce its rate of incomplete occlusion.

Endovascular coiling vs. surgical clipping for unruptured intracranial aneurysm: A meta-analysis

BACKGROUND

With increasing use of high-resolution imaging of brain, unruptured aneurysms are more and more frequently detected. With the advances in treatment techniques, an increasing number of aneurysms are now occluded using endovascular coiling instead of conventional surgical clipping. However, the better modality for unruptured intracranial aneurysm has been poorly understood.

OBJECTIVE

The objective of this meta-analysis was to compare the outcomes between endovascular coiling and surgical clipping among patients with unruptured intracranial aneurysms.

METHODS

PubMed, Embase, Web of Science, CENTRAL, and SIGLE were electronically searched from January 1, 1990 to March 13, 2012 with no language restriction for randomized or nonrandomized clinical controlled trials. Article screening and data extraction were conducted in duplicate. Results were statistically pooled through Review Manager 5 and StatsDirect 2.7.9.

RESULTS

Seven studies met our inclusion criteria. The pooled risk ratios (coiling vs. clipping) were 0.59 (95% CI = 0.23-1.54) for death; 0.37 (95% CI = 0.10-1.41) for bleeding; 0.78 (95% CI = 0.38-1.58) for cerebral ischemia; 0.87 (95% CI = 0.70-1.08) for occlusion of aneurysm; 0.53 (95% CI = 0.18-1.52) for independence in daily activities. The pooled rates of death, bleeding, ischemia, occlusion of aneurysm, and mRS no less than 3 were 1% (95% CI = 0-2%), 2% (95% CI = 0-5%), 8% (95% CI = 4-13%), 82% (95% CI = 64-95%), and 5% (95% CI = 1-10%) for endovascular coiling, respectively, and 1% (95% CI = 0-2%), 6% (95% CI = 3-10%), 9% (95% CI = 5-15%), 95% (95% CI = 90-98%), and 8% (95% CI = 3-14%) for surgical clipping, respectively. We failed to evaluate quality of life and cognitive outcome due to insufficient data. Both meta-regression and sensitivity analysis showed consistent results. Furthermore, Begg's test and Egger's test failed to detect publication bias.

CONCLUSION

We suggest that endovascular coiling and surgical clipping bear similar risk ratios of death, bleeding, cerebral ischemia, occlusion of aneurysm, and independence in daily activities and encourage further studies on quality of life and cognitive outcome. However, albeit the results in this meta-analysis are robust, due to great clinical heterogeneity and low quality of studies, the results in this meta-analysis should be interpreted with caution.

Role of endoscopy in multi-modality monitoring during aneurysm surgery: A single center experience with 175 consecutive unruptured aneurysms

Objective and Background:

Unruptured aneurysm surgery is a challenge to all vascular neurosurgeons as the patient is asymptomatic and no even slight neurological deficits should be expected postoperatively. To this aim, multi-modality checking of the vessels during the surgery is highly recommended to assure of the patency of the parent and perforator arteries next to an aneurysm. In this paper, we present our experience in the last 1.5 years with emphasis on the role of endoscope assisted microsurgery.

Methods:

One hundred and seventy-five patients with unruptured intracranial aneurysms were operated in our institute in the last 1½ years. All patients underwent endoscope assisted microsurgery with pre- and post-clipping indocyanine green angiography. In selected cases, motor evoked potential monitoring was implemented.

Results:

No mortality was observed in this period, and only 6 patients (3.4%) suffered new permanent neurological deficits postoperatively. Our illustrative cases show how endoscopy may help the surgeon to visualize hidden vessels behind and medial to an aneurysm.

Conclusions:

Our results indicated that multi-modality monitoring during unruptured aneurysm surgeries is associated with excellent outcome. Endoscope is able to show blind corners during aneurysm surgery which cannot be routinely observed with microscope and its application in aneurysm surgery assists the surgeon to make certain of complete neck clipping and preservation of perforating arteries around the aneurysm.

Stent placement for complex middle cerebral artery aneurysms

BACKGROUND

To evaluate the safety and effectiveness of stent placement for ruptured or unruptured middle cerebral artery (MCA) aneurysms in a larger number.

METHODS

Between October 2003 and December 2012, data for 70 patients with 72 complex MCA aneurysms treated with stents at our institution were retrospectively collected and analyzed.

RESULTS

Eighty-five stents were successfully deployed in this series. However, failure of followed coiling was encountered in 2 (2.8%) tiny aneurysms of them. Of the 63 aneurysms treated with stent-assisted coiling, complete occlusion was achieved in 22 (34.9%), neck remnant in 15 (23.8%), and residual sac in 26 (36.5%). Of the 9 aneurysms treated with stent alone, the results were contrast stasis in 3 aneurysms and no change in 6. Procedure-related complications occurred in 9 (12.5%) procedures, including 7 of 27 (25.9%) with ruptured aneurysms and 2 of 45 (4.4%) with unruptured aneurysms, which resulted in 1 death and 5 disabilities. Univariate and multivariate analyses show that ruptured aneurysm is an independent factor for the outcome of these patients (odds ratio, 7.35; 95% confidence interval, 1.35-40.0). Angiographic follow-up results (mean, 10.5±8.8 months) showed that 72.1% (44 of 61) were completely occluded, 4.9% (3 of 61) recurred, and others were stable or had improved. Intrastent stenosis was observed in 1 (1.6%) patient, which was managed conservatively. During a clinical follow-up period ranging from 7 to 113 months (mean, 33.0±22.4 months), 1 disabled patient died from severe pneumonia, whereas the clinical status of the others had improved or was stable. Procedure-related morbidity/mortality during the follow-up for the ruptured and unruptured groups were 3.7%/3.7% and 0/0, respectively.

CONCLUSIONS

Our study shows that stent placement for the treatment of certain wide-neck MCA aneurysms is feasible, safe, and effective. However, stent placement for acutely ruptured MCA aneurysms harbors a much higher complication rate.

Endovascular treatment of middle cerebral artery aneurysms for 120 nonselected patients: a prospective cohort study

BACKGROUND AND PURPOSE

Multiple technologies have developed the endovascular approach to MCA aneurysms. We assess the safety and the efficacy of a systematic endovascular approach in nonselected patients with MCA aneurysms and determine predictors of treatment outcomes.

MATERIALS AND METHODS

We analyzed data collected between January 2007 and January 2012 in a prospective clinical registry. All patients with MCA aneurysms treated by means of the endovascular approach were included. A multivariate analysis was conducted to identify predictors of complications, recanalization, and outcome.

RESULTS

A total of 120 patients with 131 MCA aneurysms were included. Seventy-nine patients (65.8%) were treated electively and 41 (34.2%) in the setting of subarachnoid hemorrhage. Thirty-three of 131 aneurysms (25.2%) were treated with simple coiling, 79 aneurysms (60.3%) with balloon-assisted coiling, and 19 aneurysms (14.5%) with stent-assisted coiling. Complications occurred in 13.7% of patients. Stent-assisted coiling was significantly associated with more complications (P = .002; OR: 4.86; 95% CI, 1.60-14.72). At 1 month after treatment, both the permanent morbidity (mRS ≤2) and mortality rates were 3.3%, without any significant difference according to the endovascular techniques. Mean angiographic follow-up was 16.3 months. The rate of recanalization was 15.6% without a statistical difference, according to the technique. Larger aneurysms were a predictor of recanalization (P = .016; OR: 1.183; 95% CI, 1.02-1.36). Retreatment was performed in 10 of 131 aneurysms (7.6%).

CONCLUSIONS

Even though stent-assisted coiling significantly increases the risk of procedural complications, endovascular treatment of MCA aneurysms is safe, effective, and provides durable aneurysm closure in nonselected patients.

Endovascular and Surgical Treatment of Unruptured MCA Aneurysms: Meta-Analysis and Review of the Literature

Introduction. The best treatment for unruptured middle cerebral artery (MCA) aneurysms is unclear. We perform a meta-analysis of recent publications to evaluate the results of unruptured MCA aneurysms treated with surgical clipping and endovascular coiling. Methods. A PubMed search for articles published between January 2004 and November 2013 was performed. The R statistical software package was used to create a random effects model for each desired incidence rate. Cochran's Q test was used to evaluate possible heterogeneity among the rates observed in each study. Results. A total of 1891 unruptured MCA aneurysms, 1052 clipped and 839 coiled, were included for analysis. The complete occlusion rate at 6–9 months mean follow-up was 95.5% in the clipped group and 67.8% in the coiled group (P < 0.05). The periprocedural thromboembolism rate in the clipping group was 1.8% compared with 10.7% in the aneurysms treated by coiling (P < 0.05). The recanalization rate was 0% for clipping and 14.3% for coiling (P = 0.05). Modified Rankin scores of 0–2 were obtained in 98.9% of clipped patients compared to 95.5% of coiled (NS). Conclusions. This review weakly supports clipping as the preferred treatment of unruptured MCA aneurysms. Clinical outcomes did not differ significantly between the two groups.

Endovascular treatment of 300 consecutive middle cerebral artery aneurysms: clinical and radiologic outcomes

BACKGROUND AND PURPOSE

There is controversy as to the best mode of treating MCA aneurysms. We report the results of a large endovascular series of patients treated at our center.

MATERIALS AND METHODS

This study was a retrospective analysis of a prospectively acquired data base. All patients with saccular MCA aneurysms treated between November 1996 and June 2012 were included. World Federation of Neurosurgical Societies grade, aneurysm site, size, and aneurysm neck size were recorded, along with clinical outcome assessed with the Glasgow Outcome Scale and radiographic occlusion assessed with the Raymond classification at 6 months and 2.5 years.

RESULTS

A total of 295 patients with 300 MCA aneurysms were treated including 244 ruptured aneurysms (80.7%). The technical failure rate was 4.3% (13 patients). Complete occlusion or neck remnant was achieved in 264 (91.4%). Complications included rupture in 15 patients (5%), thromboembolism in 17 patients (5.7%), and early rebleeding in 3 patients (1%). Overall permanent procedural-related morbidity and mortality were seen in 12 patients (7.8%). Of the ruptured aneurysms, 189 (79.4%) had a favorable clinical outcome (Glasgow Outcome Scale score, 4-5). A total of 33 patients (13.6%) died. On initial angiographic follow-up, aneurysm remnant was seen in 18 aneurysms (8.1%). A total of 13 patients (4.3%) were re-treated.

CONCLUSIONS

Our experience demonstrates that endovascular treatment of MCA aneurysms has an acceptable safety profile with low rates of technical failure and re-treatment. Therefore, coiling is acceptable as the primary treatment of MCA aneurysms.