Microsurgical Management of Giant Intracranial Aneurysms: A Single Surgeon Experience from Louisiana State University, Shreveport

Exploring the latest findings on endovascular treatments for giant aneurysms: a review

Giant intracranial aneurysms represent a very challenging aspect of aneurysmal pathophysiology with very high mortality and morbidity if left untreated. Their variety in clinical presentation (subarachnoid hemorrhage, cranial nerve palsy, etc.) and pathological and imaging properties (location, anatomy, presence of collateral circulation) pose serious questions regarding the best treatment option. Admirable advances have been achieved in surgical techniques, while endovascular modalities with flow diversion techniques have become widely used. However, there is still lack of data regarding whether a single endovascular technique can be the universal treatment for such cases. In this review, we aim to summarize the current funds of knowledge concerning giant intracranial aneurysms and the role of endovascular management in their treatment.

Giant cavernous aneurysms occluded by aneurysmal thrombosis, calcification, parent artery occlusion: A case report and review of literature

BACKGROUND

Patients with giant intracranial aneurysms (GIAs) are at a high risk of rupture, morbidity, and mortality even after surgical or endovascular treatment. We described a case of a spontaneously occluded GIA secondary to gradual growth of the GIA, continuously progressed aneurysmal thrombosis, complete aneurysmal calcification and complete occlusion of the parent artery-the right internal carotid artery (RICA).

CASE SUMMARY

A 72-year-old female patient complained of sudden pain in her right eye upon admission to our hospital. She had been diagnosed with a GIA [30 mm (axial) × 38 mm (coronal) × 28 mm (sagittal)] containing an aneurysmal thrombus located in the cavernous sinus segment of RICA diagnosed by magnetic resonance imaging (MRI), enhanced MRI, and magnetic resonance angiography more than 14 years ago. Later, with slow growth of the cavernous carotid GIA, aneurysmal thrombosis progressed continuously, spontaneous occlusion of the RICA, complete aneurysmal calcification, and occlusion of the GIA occurred gradually. She had no history of subarachnoid hemorrhage but missed the chance for endovascular therapy at an early stage. As a result, she was left with severe permanent sequelae from the injuries to the right cranial nerves II, III, IV, V1/V2, and VI.

CONCLUSION

The risk of rupture of the cavernous carotid GIAs was relatively low and possibly further be reduced by the stasis flow and spontaneous occlusion of the parent artery internal carotid artery (ICA) induced by the mass effect of the cavernous carotid GIAs and the extremely rare aneurysmal calcification. However, nowadays, it is advisable to recommend early endovascular treatment for the cavernous carotid GIAs to prevent injuries to the surrounding intracranial nerves and occlusion of the ICA, mainly caused by the mass effect of the cavernous carotid GIAs.

Treatment of giant intracranial aneurysms using the Pipeline flow-diverting stent: Long-term results from the International Retrospective Study of the Pipeline Embolization Device (IntrePED) study

BACKGROUND

Traditional endovascular treatments of giant intracranial aneurysms are associated with high rates of complications and retreatment. Our objective was to examine the safety and long-term efficacy of the Pipeline Embolization Device for treatment of these aneurysms.

METHODS

This retrospective study using the IntrePED database included all patients with giant intracranial aneurysms treated with the Pipeline device between July 2008 and February 2013. Efficacy outcomes were stratified by using the Raymond-Roy Occlusion Classification. Predefined safety outcomes included spontaneous rupture of the target aneurysm; ipsilateral intracranial hemorrhage; ischemic stroke; parent artery stenosis; and sustained cranial neuropathy.

RESULTS

Sixty-six embolizations were performed to treat 63 giant intracranial aneurysms (including 2 ruptured): 49 (77.8%) in the anterior and 14 (22.2%) in the posterior circulation. The median follow-up was 22.4 (0.1-60.5) months. Class I angiographic occlusion was achieved in 72.0% (36/50). The neurological morbidity/mortality rate was 23.8% (15/63), with higher rates in the posterior circulation than in the anterior circulation (22.4% vs. 28.6%). Among seven deaths, five had neurological causes. The procedure-related neurological morbidity and mortality rates were 22.7% (15/66) and 7.6% (5/66), respectively. The spontaneous rupture rate was 4.5% (3/66). Two spontaneous ruptures (1 death), 4/4 postprocedural intracranial hemorrhages, and 6/9 ischemic events occurred within 30 days. In-stent stenosis and new-onset cranial neuropathy were not observed during the angiographic follow-up period.

CONCLUSIONS

Although procedure-related neurological morbidity/mortality rates were not insignificant, this study confirms the feasibility and long-term efficacy of the Pipeline Embolization Device to treat giant intracranial aneurysms.

Dolenc approach for clipping of giant C6 and C7 segment aneurysms of the internal carotid artery

Objective

Surgical treatment for giant aneurysms of the ICA-ophthalmic segment (C6) and communicating artery segment (C7) is a challenge for neurosurgeons because of their high risks and poor outcomes. We aim to explore the advantages and disadvantages of the Dolenc approach in the treatment of giant C6-C7 segment aneurysms.

Methods

We retrospectively reviewed the clinical data of 13 cases with giant C6 aneurysms and 4 cases with giant C7 aneurysms treated with the Dolenc approach.

Results

All 17 cases of aneurysms were clipped successfully using the Dolenc approach, of which, 1 case with ipsilateral MCA occlusion underwent extracranial-intracranial artery bypass after the aneurysm clipping. Regarding clinical outcomes, six out of nine cases with preoperative visual impairment improved after surgery, two cases saw no change, and one case deteriorated. Of all the cases, one had new-onset vision loss, four had new-onset oculomotor paralysis, three had surgical side cerebral infarction, and two had diabetes insipidus. DSA or CTA examination within 2 weeks after surgery showed that all aneurysms were completely clipped without residual. After a follow-up of 9-12 months, 17 patients were evaluated based on GOS and CTA examination. A total of 14 cases had GOS 5 scores, 2 cases had GOS 4 scores, 1 case had GOS 2 scores, and no cases had death. None of the patients had recurrence based on CTA examinations.

Conclusion

Through the Dolenc approach, we could achieve more operation space and expose clinoid segments for temporary occlusion. Therefore, the Dolenc approach was shown to be a safe, effective, and feasible treatment for giant C6-C7 aneurysms.

Endovascular Management of Vertebrobasilar Trunk Artery Large Aneurysms: Complications and Long-Term Results

Objective

To analyze the complications and long-term results of endovascular management of vertebrobasilar trunk large (≥10 mm) aneurysms (VBTLAs) and identify predictors of outcomes.

Methods

Between 2014 and 2020, 6,987 patients with intracranial aneurysms were referred to our center for aneurysm management and 2,224 patients have undergone the endovascular procedures. We retrospectively reviewed the database and identify all the patients with VBTLAs.

Results

A total of 62 VBTLAs were identified. The median aneurysm size was 13.4 mm [interquartile range (IQR) 11.5–18.7]. Among them, 24 aneurysms were treated with overlapping stent techniques, 18 aneurysms were treated with flow diversion, 14 aneurysms were treated with single stent-assisted coiling, and 6 aneurysms were treated with coiling alone. Ten patients were treated with parent artery occlusion or unilateral vertebral artery occlusion. Periprocedural complications were occurred in 7 (11.3%) patients. Clinical follow-up was obtained at the median of 27.5 months (IQR 15.3–58.5). The overall complication rate was 16.1% (10/62), including nine ischemic events and one hemorrhagic event. The combined disability and neurological mortality rate was 12.9% (8/62), with 4 (6.5%) deaths. The favorable outcome rate at follow-up was 87.1% (54/62). The complication-free cumulative survival rates at 1 and 5 years were 86.8 and 82.0%, respectively. The overall cumulative survival rates at 1 and 5 year were 96.5 and 89.8%, respectively. In the multivariate Cox regression analysis, longer procedure time (>115 min) (P = 0.037) and ischemic onset (P = 0.005) predict complications. Angiography follow-up was available for 36 patients at the median of 6.0 months (IQR 6–12), with a complete occlusion rate of 77.8% (28/36). Two (5.6%) aneurysms were recanalized and subsequently received the retreatment. Subgroup analysis did not find any differences in the complete occlusion rate between endovascular strategies.

Conclusion

Endovascular management of VBTLAs has a reasonable safety profile with favorable 5-year cumulative survival rates and imaging outcomes at follow-up. Prolonged procedure and ischemic onset are associated with a high risk of overall complications.

Long-term Follow-up Results after Flow Diverter Therapy Using the Pipeline Embolization Device for Large or Giant Unruptured Internal Carotid Artery Aneurysms: Single-center Retrospective Analysis in the Japanese Population

Flow diverter (FD) therapy using Pipeline embolization device (PED) has become an important alternative to treat internal carotid artery (ICA) aneurysms. Herein, we report the long-term outcome for 3 years after FD therapy using PED for ICA aneurysms in Japan. The patients who underwent angiographical and/or clinical follow-up for 3 years after the FD therapy using PED of large or giant unruptured ICA aneurysms from December 2012 at our university hospital are the subjects of this study. We retrospectively reviewed the in- and outpatients’ medical charts, and written operative and radiological records. There were 84 patients with 90 aneurysms who could be clinically and/or angiographically followed up for 3 years. Of these, 7 aneurysms were only available for clinical follow-up. Of the remaining 83 aneurysms, 6 aneurysms had vessel occlusion due to stent thrombosis or parent artery occlusion, and 60 of the remaining 77 (77.9%) had complete occlusion. In multivariate analysis, older age (>70 years), wide neck, and non-adjunctive coiling contributed statistically significantly to incomplete occlusion. Of the 84 patients, 2 patients (2.4%) had delayed complications between 6 months and 3 years after the initial FD placement. Three patients (3.6%) had poor outcome due to postoperative major stroke complications, 2 of which were acute complications. The long-term results after FD therapy are good both angiographically and clinically. Endothelialization of the aneurysmal neck and intra-aneurysmal thrombosis contribute to complete occlusion. The primary reason for the somewhat low complete occlusion in Japan may be the patients are generally older.

Microsurgery of Giant Intracranial Aneurysm: A Single Institution Outcome Study

Background

Giant intracranial aneurysms (GIAs) are treacherous lesions and in spite of the many advances, endovascular therapy (EVT) of GIAs is challenging.

Objective

A retrospective analysis of our results with microsurgery of GIAs is presented to examine the role of microsurgery in the current trend of EVT.

Materials and Methods

Between 1996 and 2019, 134 patients with 147 GIAs had microsurgery by the senior author in a single institute. The medical and imaging records for all the patients were reviewed. The patient outcome was determined by modified Rankin scale (mRS); ≤3 was considered as a good outcome. Statistical analysis was done using the SPSS program and odds ratios and their 95% confidence intervals were computed; a probability value of < 0.05 was considered significant.

Results

There were 123 aneurysms (83.7%) in the anterior circulation and 24 aneurysms (16.3%) in the posterior circulation. Overall 103 out of 134 (76.8%) patients had a good outcome postoperatively. Good preoperative mRS score (≤3) had an overall good prognosis in the postoperative period and was statistically significant (P = 0.000, odds ratio: 0.036, 95% CI: 0.008-0.171). Presence of subarachnoid hemorrhage (SAH) was also statistically significant for good outcome (P = 0.04, odds ratio: 2.898, 95% CI: 1.051-7.991), but age was not a significant prognostic factor. Mortality within 30 days of treatment was 4.47%.

Conclusion

GIAs need treatment because of their dismal natural history. Results of microsurgical treatment by a single surgeon of the large current series compare well with the results of EVT and justifies pursuing microsurgery for GIAs.

Surgical Management of Giant Intracranial Aneurysms: Overall Results of a Large Series

OBJECTIVE

To review and discuss surgical treatment options for giant intracranial aneurysms (GIAs), focusing on indications, technical aspects, and results, along with some illustrative cases.

METHODS

We reviewed the data of 82 consecutive patients surgically managed between January 2000 and December 2019 for treatment of a GIA.

RESULTS

Male sex and hemorrhage at presentation were prevalent. The average follow-up was 81.2 ± 45 months. The anterior circulation was involved in 76.8% of GIAs. If the GIA showed a clear neck, minimal atherosclerosis, or intrasaccular thrombosis, and ≤2 branches arising from the neck, it was reconstructed. This procedure was possible in 78% of cases. The technique also involved temporary clipping, remodeling, and thrombectomy, as well as fragmentation techniques. Angioarchitectural features other than these techniques underwent bypass and aneurysm trapping. Most bypasses were extracranial to intracranial and high flow. Flow capacity, collateral circulation, and availability of the donor vessel mainly affected the choice of the type of bypass. Overall, successful exclusion of the GIA was 91.4%. The need for retreatment and complication rate were 3.6% and 19.5%, respectively. A good overall outcome (modified Rankin Scale score 0-3) was achieved in 84.2% of patients, and mortality was 10%.

CONCLUSIONS

Microneurosurgical techniques still maintain a significant role for most GIAs, with a high durability and acceptable rate of morbidity and mortality. Clip reconstruction is the first-line surgical treatment option, whereas bypass is indicated in cases of planned or unplanned sacrifice of the parent artery to prevent long-term ischemic complications.

Multimodal management of giant cerebral aneurysms: review of literature and case presentation

The pathophysiology of giant cerebral aneurysms renders them difficult to treat. Advances in technology have attempted to address any shortcomings associated with open surgery or endovascular therapies. Since the introduction of the flow diversion technique, the endovascular approach with flow diversion has become the first-line modality chosen to treat giant aneurysms. A subset of these giant aneurysms may persistent despite any treatment modality. Perhaps the best option for these recurrent and/or persistent giant aneurysms is to employ a multimodal approach-both surgical and endovascular-rather than any single technique to provide a curative result with favourable patient outcomes. This paper provides a review of the histopathology and treatment options for giant cerebral aneurysms. Additionally, an illustrative case is presented to highlight the unique challenges of a curative solution for giant cerebral aneurysms that persist despite initial treatment.

Microsurgical outcome of unruptured giant intracranial aneurysms: A single-center experience

Microsurgical treatment of unruptured giant intracranial aneurysms (GIAs) is challenging. Although previous studies regarded clipping as the first option to repair GIAs, quite a number of GIAs are not clippable. We conducted this study to evaluate the postoperative complications and long-term outcome of patients with unruptured GIAs treated by different microsurgical modalities. We retrospectively reviewed 505 consecutive patients with unruptured intracranial aneurysms (UIAs) who were surgically treated in our department from 2012 to 2015. Patients with UIAs of which diameter ≥2.5 cm were studied. We reported the characteristics of patients and GIAs. Postoperative major complications were observed, and patient functional status were assessed with the modified Rankin Scale (mRS) at discharge and at the last follow-up. Twenty-one patients with unruptured GIAs were analysed, of whom 12 patients were treated by clipping, whereas 9 patients with unclippable aneurysms were treated by trapping or parent vessel occlusion. Fourteen aneurysms were saccular, and 7 were fusiform or serpentine. The mean aneurysm size was 3.7 ± 1.5 cm. After surgery, major complications were observed in 13 of the 21 (61.9%) patients. One (4.8%) patient died during hospital. After a mean 5.2-year follow-up, 9 (75.0%) patients treated by clipping and 7 (77.8%) treated by non-clipping experienced a good outcome (mRS ≤2). We found no significant difference in both postoperative complications and long-term outcome between clipping and non-clipping group. Favorable prognosis can be obtained in most patients with unruptured GIAs treated by appropriate microsurgical modality.

Is surgical parent artery occlusion effective for intracranial aneurysms measuring over 10 mm in size? Result from long-term follow-up of size changes and outcomes

BACKGROUND

There have been no long-term follow-up reports pertaining to chronological size changes in large or giant unruptured intracranial aneurysms treated with surgical parent artery occlusion (PAO). The object of this study is to investigate the utility and safety of surgical PAO by conducting a long-term follow-up of chronological aneurysm size changes and outcomes.

METHODS

A retrospective study of 21 unruptured intracranial aneurysms measuring over 10 mm (20 patients) treated with surgical PAO in the period 2012-2017 was conducted. For aneurysms presenting with anterior circulation, high/low flow bypass was chosen and carried out concomitantly on the basis of preoperative balloon occlusion test results. Aneurysm size before and after surgery was evaluated chronologically using maximum diameter measurements taken from the same slice of MRI T2-weighted images. Moreover, post-surgery outcomes were evaluated according to a modified Rankin scale (mRS) at discharge.

RESULTS

PAO aiming for blind-alley formation was performed in 20 of 21 aneurysms (95.2%). Aneurysm size reduction was confirmed in 20 aneurysms (95.2%) after proper PAO, with an average reduction rate of 63.1% (range, 28-95%), during an average follow-up period of 27 months (range, 4-54 months). Eighteen (90.4%) of the 20 patients with 21 aneurysms returned to previous life with mRS score 0-2. With regard to preoperative symptoms, diplopia and visual impairment had improved in three patients (50%) and one patient (100%), respectively. Ischemic complications had occurred in five patients, two (9.6%) of whom were symptomatic and three (14.3%) were asymptomatic. The mortality rate in this study was 0%.

CONCLUSIONS

Surgical PAO for unruptured intracranial aneurysms measuring over 10 mm has been shown to be an effective method of treatment, eliciting a reduction in aneurysm size.

Internal Carotid Artery Bifurcation Aneurysms: Microsurgical Strategies and Operative Nuances for Different Aneurysmal Directions

BACKGROUND

Internal carotid artery bifurcation aneurysms (ICAbifAs), comprising approximately 5% of intracranial aneurysms, are characterized clinically by their tendency to occur at a younger age and surgically by the technical difficulties posed by their domes being adherent to the frontal lobe, their location at the apex of the sylvian fissure, and their relation to myriad perforator complexes.

OBJECTIVE

To review the nuances of technique and operative strategy specific to aneurysmal direction in the light of our experience with ICAbifAs.

METHODS

ICAbifAs managed at our institute from January 2001 to July 2016 were analyzed. Detailed analysis of clinical data, pre- and postoperative radiology, operative notes and videos, and clinical outcome was done.

RESULTS

Fifty-one patients with ICAbifAs were treated in the study period out of which 40 patients underwent microsurgical clipping. The median age was 48 yr (range 14-68 yr). Nearly 95% of the patients presented in a good clinical grade (World Federation of Neurological Surgeons grade 1 and 2). At 6-mo follow-up, 36 patients (90%) had good clinical outcome (Glasgow Outcome Scale 4 and 5). According to their direction, ICAbifAs were grouped as anteriorly directed (10 cases), superiorly directed (23 cases), and posteriorly directed (7 cases). Operative techniques and nuances utilized depend on aneurysmal direction and are presented here.

CONCLUSION

An appropriate surgical strategy based on the direction of ICAbifAs as per the preoperative radiology, meticulous dissection of aneurysmal wall from adjacent perforators, and clip application with the aim of remodeling the ICA bifurcation are integral to achieving a good outcome.

Pipeline for uncoilable or failed aneurysms: 3-year follow-up results

OBJECTIVE

The long-term effectiveness of endovascular treatment of large and giant wide-neck aneurysms using traditional endovascular techniques has been disappointing, with high recanalization and re-treatment rates. Flow diversion with the Pipeline Embolization Device (PED) has been recently used as a stand-alone therapy for complex aneurysms, showing significant improvement in effectiveness while demonstrating a similar safety profile to stent-supported coil treatment. However, relatively little is known about its long-term safety and effectiveness. Here the authors report on the 3-year safety and effectiveness of flow diversion with the PED in a prospective cohort of patients with large and giant internal carotid artery aneurysms enrolled in the Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial.

METHODS

The PUFS trial is a prospective study of 107 patients with 109 aneurysms treated with the PED. Primary effectiveness and safety end points were demonstrated based on independently monitored 180-day clinical and angiographic data. Patients were enrolled in a long-term follow-up protocol including 1-, 3-, and 5-year clinical and imaging follow-up. In this paper, the authors report the midstudy (3-year) effectiveness and safety data.

RESULTS

At 3 years posttreatment, 74 subjects with 76 aneurysms underwent catheter angiography as required per protocol. Overall, complete angiographic aneurysm occlusion was observed in 71 of these 76 aneurysms (93.4% cure rate). Five aneurysms were re-treated, using either coils or additional PEDs, for failure to occlude, and 3 of these 5 were cured by the 3-year follow-up. Angiographic cure with one or two treatments of Pipeline embolization alone was therefore achieved in 92.1%. No recanalization of a previously completely occluded aneurysm was noted on the 3-year angiograms. There were 3 (2.6%) delayed device- or aneurysm-related serious adverse events, none of which led to permanent neurological sequelae. No major or minor late-onset hemorrhagic or ischemic cerebrovascular events or neurological deaths were observed in the 6-month through 3-year posttreatment period. Among 103 surviving patients, 85 underwent functional outcome assessment in which modified Rankin Scale scores of 0–1 were demonstrated in 80 subjects.

CONCLUSIONS

Pipeline embolization is safe and effective in the treatment of complex large and giant aneurysms of the intracranial internal carotid artery. Unlike more traditional endovascular treatments, flow diversion results in progressive vascular remodeling that leads to complete aneurysm obliteration over longer-term follow-up without delayed aneurysm recanalization and/or growth.

Clinical trial registration no.: NCT00777088 (clinicaltrials.gov)

Surgical Resection and Histopathological Analysis of a Thrombosed Giant Fusiform MCA Aneurysm After Initial Treatment with a Flow Diversion Construct

BACKGROUND

We describe the histopathology of an unruptured giant calcified left middle cerebral artery (MCA) fusiform aneurysm initially treated with endovascular flow diversion. The flow diversion construct underwent postoperative in-stent thrombosis, necessitating surgical resection of the aneurysm to eliminate mass effect.

METHODS

A 75-year-old woman with a known left MCA aneurysm presented to the emergency department with moderate right hemibody weakness. Owing to the clinical and radiographic progression of the aneurysm, the patient was offered treatment. She was initially offered open surgical management of the lesion but declined it, indicating that she would consider only endovascular treatment. The patient underwent endovascular reconstruction of the aneurysmal segment with an overlapping pipeline construct. Postoperatively, the patient experienced in-stent thrombosis of the pipeline construct. The thrombosed aneurysm exerted a progressive local mass effect, necessitating en bloc surgical resection of the aneurysm and stent construct. The aneurysm was submitted for pathological analysis, which demonstrated chronologically older thrombus outside the flow diversion construct.

RESULTS

Postsurgical imaging demonstrated a left MCA territory stroke. The patient gradually gained strength in her right hemibody. The histopathological analysis indicated that the degrees of platelet activation and clot formation in this case were dependent on the aggregate surface area of the thrombus and surface area of the pipeline device used in the reconstruction.

CONCLUSIONS

This technical report with histopathological analysis provides useful insight into the mechanism of aneurysmal thrombosis after flow diversion. It also raises new questions regarding the roles of thrombus formation, platelet aggregation, and stent construct surface area in the maintenance of vessel patency.

Unexpected Rupture of a Giant Lobulated Thrombotic Middle Cerebral Artery Aneurysm and Emergency Surgical Treatment With Thrombectomy: A Case Report and Review of the Literature

Introduction

The treatment of giant intracranial aneurysms is one of the most challenging cerebrovascular problems of neurosurgery. We report the rupture of a giant, lobulated, and almost completely thrombosed middle cerebral artery (MCA) aneurysm that is the ninth such report in the literature. We also investigated additional solutions used in the treatment of this patient.

Case Presentation

A 58-year-old man had been admitted with headache 8 years previously (in 2005), and a giant MCA aneurysm was detected. Two separate endovascular interventions were performed, and both failed. The patient began to live with the giant aneurysm. As there was a large thrombosis filling the aneurysm lumen during the previous endovascular procedures, the aneurysm was not expected to rupture. However, a rupture eventually occurred, in 2013. Even if an aneurysm is very large, lobulated, old, and almost completely thrombosed, it can suddenly bleed. During surgery on this patient, we observed severe cerebral vasospasm caused by a giant thrombosed aneurysmal rupture. Despite the complications, surgery is a life-saving treatment for this emergency when other strategies are not possible. Thrombectomy and clipping are approaches that require a great deal of courage for the neurosurgeon, in terms of entering the risky area within the aneurysm.

Conclusions

We believe that it would be more appropriate to plan for combined treatment with surgical and endovascular approaches before the emergency condition could occur.

Outcome of Surgical or Endovascular Treatment of Giant Intracranial Aneurysms, with Emphasis on Age, Aneurysm Location, and Unruptured Aneuryms - A Systematic Review and Meta-Analysis

Background: Designing treatment strategies for unruptured giant intracranial aneurysms (GIA) is difficult as evidence of large clinical trials is lacking. We examined the outcome following surgical or endovascular GIA treatment focusing on patient age, GIA location and unruptured GIA. Methods: Medline and Embase were searched for studies reporting on GIA treatment outcome published after January 2000. We calculated the proportion of good outcome (PGO) for all included GIA and for unruptured GIA by meta-analysis using a random effects model. Results: We included 54 studies containing 64 study populations with 1,269 GIA at a median follow-up time (FU-T) of 26.4 months (95% CI 10.8-42.0). PGO was 80.9% (77.4-84.4) in the analysis of all GIA compared to 81.2% (75.3-86.1) in the separate analysis of unruptured GIA. For each year added to patient age, PGO decreased by 0.8%, both for all GIA and unruptured GIA. For all GIA, surgical treatment resulted in a PGO of 80.3% (95% CI 76.0-84.6) compared to 84.2% (78.5-89.8, p = 0.27) after endovascular treatment. In unruptured GIA, PGO was 79.7% (95% CI 71.5-87.8) after surgical treatment and 84.9% (79.1-90.7, p = 0.54) after endovascular treatment. PGO was lower in high quality studies and in studies presenting aggregate instead of individual patient data. In unruptured GIA, the OR for good treatment outcome was 5.2 (95% CI 2.0-13.0) at the internal carotid artery compared to 0.1 (0.1-0.3, p < 0.1) in the posterior circulation. Patient sex, FU-T and prevalence of ruptured GIA were not associated with PGO. Conclusions: We found that the chances of good outcome after surgical or endovascular GIA treatment mainly depend on patient age and aneurysm location rather than on the type of treatment conducted. Our analysis may inform future research on GIA.

The expanding realm of endovascular neurosurgery: flow diversion for cerebral aneurysm management

The worldwide prevalence of intracranial aneurysms is estimated to be between 5% and 10%, with some demographic variance. Subarachnoid hemorrhage secondary to ruptured intracranial aneurysm results in devastating neurological outcomes, leaving the majority of victims dead or disabled. Surgical clipping of intracranial aneurysms remained the definitive mode of treatment until Guglielmi detachable coils were introduced in the 1990s. This revolutionary innovation led to the recognition of neurointervention/neuroendovascular surgery as a bona fide option for intracranial aneurysms. Constant evolution of endovascular devices and techniques supported by several prospective randomized trials has catapulted the endovascular treatment of intracranial aneurysms to its current status as the preferred treatment modality for most ruptured and unruptured intracranial aneurysms. We are slowly transitioning from the era of coils to the era of flow diverters. Flow-diversion technology and techniques have revolutionized the treatment of wide-necked, giant, and fusiform aneurysms, where the results of microsurgery or conventional neuroendovascular strategies have traditionally been dismal. Although the Pipeline Embolization Device (ev3-Covidien, Irvine, CA) is the only flow-diversion device approved by the Food and Drug Administration for use in the United States, others are commercially available in Europe and South America, including the Silk (Balt Extrusion, Montmorency, France), Flow-Redirection Endoluminal Device (FRED; MicroVention, Tustin, CA), Surpass (Stryker, Kalamazoo, MI), and p64 (Phenox, Bochum, Germany). Improvements in technology and operator experience and the encouraging results of clinical trials have led to broader acceptance for the use of these devices in cerebral aneurysm management. Continued innovation and refinement of endovascular devices and techniques will inevitably improve technical success rates, reduce procedure-related complications, and broaden the endovascular therapeutic spectrum for varied aneurysm morphology.

Microsurgical management of basilar artery apex aneurysms: a single surgeon's experience from Louisiana State University, Shreveport

OBJECTIVE

Basilar artery apex aneurysms continue to generate technical challenges and management controversy. Endovascular intervention is becoming the mainstay in the management of these formidable aneurysms, but it has limitations, especially with large/giant or wide neck basilar apex aneurysms. There is paucity of data in the available literature pertaining to the successful management of large/giant, wide neck, and calcified/thrombosed basilar apex aneurysms. We present our experience with consecutively operated complex basilar apex aneurysms so as to present the role of microneurosurgery as a viable management option for these aneurysms.

METHODS

Ours is a retrospective analysis of case-records for operated cases of basilar artery aneurysms spanning 18 years. Basilar apex aneurysms >10 cm, calcified or thrombosed, neck ≥4 mm posterior direction, and retro/subsellar were considered as complex anatomy aneurysms. Basilar apex aneurysms with favorable anatomy were included in the study as a reference group for statistical analysis. Patient demographics, complex features of aneurysms, clinical grade, and outcomes were analyzed.

RESULTS

A total of 33 (53.2%) patients had complex anatomy: large (>10 mm) in eight (24.2%); giant aneurysms (>25 mm) in seven (21.2%); wide-neck in 22 (66.7%); and calcified/thrombosed morphology in five (15.1%). The mean age was 48.5 years, and 22 (66.67%) were women. All aneurysms were clipped by the use of various skull base approaches. A total of 71.9% of patients harboring complex aneurysm had good outcomes. If only unruptured and good grade complex aneurysms also are considered, then 86.9% (n = 20) patients had good outcomes. Statistically there was no significant difference in the outcomes of complex and noncomplex aneurysm.

CONCLUSIONS

Although concerning, the management of large/giant, wide neck, and calcified/thrombosed aneurysms with microneurosurgery is still a competitive alternative to endovascular therapy. After careful selection of appropriate skull base approaches based on the complexity of the basilar apex aneurysm, microneurosurgery can achieve acceptable results.