Safety and efficacy of adjunctive balloon remodeling during endovascular treatment of intracranial aneurysms: a literature review

Evaluating the Balloon-Assisted Rapid Intermittent Sequential Coiling Technique for the Treatment of Wide-Neck Cerebral Aneurysms

BACKGROUND

 Balloon-assisted coiling (BAC) is acknowledged as an auxiliary method for the endovascular treatment of difficult wide-necked cerebral aneurysms (WNCAs). An intracranial stent may be necessary as a supportive scaffold when the anatomical conditions are unfavorable, as BAC alone may be inadequate to avoid coil protrusion into the parent artery. We aimed to evaluate the safety of the balloon-assisted rapid intermittent sequential coiling technique (BARISCT) and the effectiveness of BARISCT in reducing the risk of coil prolapse in the primary artery during the coiling of WNCA.

METHODOLOGY

 From March 2021 to April 2023, a quasi-experimental investigation was conducted on more than 19 patients with WNCA who visited the Neurointervention Unit at Suez Canal University Hospital and fulfilled the inclusion criteria of WNCA, specifically defined by an unfavorable dome-to-neck ratio of less than 2 or a neck length exceeding 4 mm.

RESULTS

 BARISCT has proven to be a safe and successful tool for occluding ruptured and unruptured WNCA, with a full occlusion rate of roughly 73% with minimum sequelae and no major complications.

CONCLUSION

 BARISCT seems to be a method that is both safe and successful for the endovascular treatment of wide-neck intracranial aneurysms (WNCA), with no concern regarding the potential for an increase in the likelihood of complications.

Treatment of saccular wide-neck intracranial aneurysm using Leo baby stent: a single-center experience based on 156 cases

To describe the mid-term safety and efficacy of Leo baby stent applied in saccular wide-neck intracranial aneurysms (IAs). 151 patients harboring 156 IAs treated with Leo baby stent from March 2021 to October 2023 were enrolled for further analysis. Among 156 IAs, 142 cases (91.0%) received one single Leo baby stent deployment while 14 cases (9.0%) received dual stents deployment. Stent-assisted coiling strategy was applied in all cases and the success rate was 100%. Immediate IAs occlusion results showed that 48 cases (30.8%) obtained Raymond grade I, 39 cases (25.0%) obtained Raymond grade II and 69 cases (44.2%) obtained Raymond grade III. Perioperative complications occurred in 10 cases (6.4%). Overall morbidity rate was 3.5% and mortality rate was 0% during follow-up. Clinical follow-up was available in 141 patients (93.4%). 136 patients (96.5%) got favorable clinical prognosis (mRS score 0-2) while 5 patients (3.5%) were in a poor neurological condition (mRS score 3-6). Angiographic follow-up was available in 136 cases (87.2%). The results showed that Raymond grade I was obtained in 112 cases (82.4%), Raymond grade II was obtained in 11 cases (8.1%) and Raymond grade III was obtained in 13 cases (9.6%). 4 cases (2.9%) were confirmed with IAs recurrence and received retreatment. Asymptomatic in-stent stenosis was detected in 8 patients (5.9%). The results demonstrate that stent-assisted coiling using Leo baby stent with favorable IAs embolization rate and the low complication rate is a feasible way in treating complex IAs.

Advancements in Brain Aneurysm Management: Integrating Neuroanatomy, Physiopathology, and Neurosurgical Techniques

Brain aneurysms, characterized by abnormal bulging in blood vessels, pose significant risks if ruptured, necessitating precise neuroanatomical knowledge and advanced neurosurgical techniques for effective management. This article delves into the intricate neuroanatomy relevant to brain aneurysms, including the vascular structures and critical regions involved. It provides a comprehensive overview of the pathophysiology of aneurysm formation and progression. The discussion extends to modern neurosurgical approaches for treating brain aneurysms, such as microsurgical clipping, endovascular coiling, and flow diversion techniques. Emphasis is placed on preoperative planning, intraoperative navigation, and postoperative care, highlighting the importance of a multidisciplinary approach. By integrating neuroanatomical insights with cutting-edge surgical practices, this article aims to enhance the understanding and treatment outcomes of brain aneurysms.

Endovascular treatment of intracranial aneurysms: Past and present

Intracranial aneurysm is common in stroke and, once rupturing, will cause disaster to patients. Nowadays, endovascular treatment has become a routine to reduce the risk of intracranial aneurysms rupture. Successive endovascular methods, like balloon-assisted coiling, stent-assisted coiling, and flow diversion, have become new choices for doctors. More and more doctors have been entering this field. Understanding the current general situation is crucial for more medical workers to learn the endovascular treatment of intracranial aneurysms. In the past, many devices and ideas about the treatment of intracranial aneurysms appeared. Although developing unceasingly, endovascular treatment still has some deficiencies to overcome. The advantages and drawbacks of current endovascular methods are discussed.

Endovascular Embolization of Intracranial Aneurysms Using Target Tetra Detachable Coils: Angiographic and Clinical Results from a Single Center

Background/Objectives: Target tetra detachable coils (TTDCs) aid in achieving effective framing during the coil embolization of small intracranial aneurysms by maintaining a tetrahedral conformation within the aneurysm sac. We aimed to report the initial experience of patients treated for intracranial aneurysms using TTDCs, with a specific focus on efficacy and safety. Methods: We retrospectively reviewed the medical records of 41 patients who underwent the coil embolization of intracranial aneurysms sized ≤10 mm with TTDCs between April and May 2023. Post-procedural angiographic and clinical results were reviewed. Results: Of the 46 aneurysms (45 unruptured and 1 ruptured), 33 (71.7%) were treated with the stent-assisted technique and 13 (28.3%) using the simple coil embolization technique. Post-procedural angiography showed complete occlusion in 41 aneurysms (89.1%), neck remnants in 1 (2.2%), and residual aneurysms in 4 (8.7%). The mean packing density was 34.7% (19.3-46.8%), with TTDC coil length comprising a mean of 88.5% of the total coil length. No major device- or procedure-related complications were observed. During the follow-up, 40 aneurysms (93.0%) demonstrated complete occlusion, while neck remnants were observed in 1 (2.3%), and residual aneurysms in 2 (4.7%). No cases of recanalization were observed. Conclusions: The TTDC is a safe and effective device for the endovascular treatment of intracranial aneurysms. Follow-up studies are required to establish long-term results.

ARISE I Consensus Review on the Management of Intracranial Aneurysms

BACKGROUND

Intracranial aneurysms (IAs) remain a challenging neurological diagnosis associated with significant morbidity and mortality. There is a plethora of microsurgical and endovascular techniques for the treatment of both ruptured and unruptured aneurysms. There is no definitive consensus as to the best treatment option for this cerebrovascular pathology. The Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts discussed best practices and the most promising approaches to improve the management of brain aneurysms.

METHODS

A group of experts from academia, industry, and federal regulators convened to discuss updated clinical trials, scientific research on preclinical system models, management options, screening and monitoring, and promising novel device technologies, aiming to improve the outcomes of patients with IA.

RESULTS

Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts suggested the incorporation of artificial intelligence to capture sequential aneurysm growth, identify predictors of rupture, and predict the risk of rupture to guide treatment options. The consensus strongly recommended nationwide systemic data collection of unruptured IA radiographic images for the analysis and development of machine learning algorithms for rupture risk. The consensus supported centers of excellence for preclinical multicenter trials in areas such as genetics, cellular composition, and radiogenomics. Optical coherence tomography and magnetic resonance imaging contrast-enhanced 3T vessel wall imaging are promising technologies; however, more data are needed to define their role in IA management. Ruptured aneurysms are best managed at large volume centers, which should include comprehensive patient management with expertise in microsurgery, endovascular surgery, neurology, and neurocritical care.

CONCLUSIONS

Clinical and preclinical studies and scientific research on IA should engage high-volume centers and be conducted in multicenter collaborative efforts. The future of IA diagnosis and monitoring could be enhanced by the incorporation of artificial intelligence and national radiographic and biologic registries. A collaborative effort between academic centers, government regulators, and the device industry is paramount for the adequate management of IA and the advancement of the field.

Double-catheter technique for the embolization of recurrent cerebral aneurysms: A single-center experience

Background

Recurrent cerebral aneurysms have complex shapes and are often technically challenging to treat with a single microcatheter. This study evaluates the clinical characteristics and treatment outcomes of patients who received double-catheter coil embolization for recurrent cerebral aneurysms.

Methods

Patients who underwent double-catheter coil embolization at our institution between April 2011 and March 2022 for recurrent aneurysms were included in the study. Baseline characteristics, course to recurrence, details of the procedures, and outcomes after endovascular treatment were retrospectively analyzed based on past medical records.

Results

Eight patients with recurrent aneurysms were treated with the double-catheter technique. One patient had a subarachnoid hemorrhage due to a rupture of a recurrent aneurysm and the others had radiological recurrence during follow-up. The initial treatment for the aneurysm was clipping in one case and coiling in seven cases. All the aneurysms were located at bifurcation sites. During retreatment, balloon remodeling technique was used in five cases. Angiographic features immediately after the treatment included complete occlusion in one case, neck remnant in three cases, and dome filling in four cases. There were no procedure-related severe complications, besides preexisting oculomotor nerve palsy due to the mass effect of the aneurysm worsened in one patient. The mean follow-up period after retreatment was 4.3 years. There was one case of recurrence after retreatment in which additional endovascular coiling was necessary.

Conclusion

This study demonstrated that the double-catheter technique could be a safe and useful treatment option for patients with recurrent aneurysms at bifurcation sites.

WEB vs coiling in ruptured aneurysms: A propensity score matched comparison of safety and efficacy

BACKGROUND

We aim to compare the safety and efficacy of WEB with coiling for acutely ruptured aneurysms.METHODS: All consecutive ruptured aneurysms with width suitable for WEB (2-10 mm) treated over 5 years (1/1/2015 to 31/12/2019) were included. We recorded WFNS, Fisher grade, patient demographics and aneurysm characteristics (size, location, D/W and aspect ratio, lobulation). Primary endpoints were mRS status at 3 months, aneurysm occlusion on latest available imaging follow-up, retreatment rate and procedural complications. We applied propensity score matching using aneurysm morphology (size, D/N ratio, ASPECT ratio and lobulation) to optimise matching for WEB versus coil comparison and minimise the effects of confounding.

RESULT

A total of 493 patients were identified, 97 treated with the WEB device. 1:1 propensity score matching was used to establish a matched group of 97 patients treated with coiling. The WEB arm showed 3% procedural complication rate, with no haemorrhagic complications and use of adjunctive device in 4%. Satisfactory occlusion on follow-up (mean 14 months) was 79%, with 19% retreatment rate. The coil arm had 8% complication rate, with use of an adjunctive device in 52% of cases (balloon 44%, stent 8%). Satisfactory occlusion on follow-up (mean 22 months) was 90%, with 8% retreatment rate.

CONCLUSION

Treatment of ruptured wide-necked bifurcation aneurysms with WEB has a lower complication rate than coiling with high rate of satisfactory occlusion. However, there was a higher retreatment rate when compared with patients treated with coiling. An adjunct device (balloon or stent), was used in over 50% of aneurysms in the coiling group.

Dual-Lumen Balloon-Assisted Coiling and Staged Flow Diversion for Ruptured Wide-Necked Posterior Communicating Artery Aneurysm: Two-Dimensional Operative Video

Endovascular treatment of acutely ruptured wide-necked aneurysms presents well-known challenges because of the desire to avoid intracranial stenting with attendant dual antiplatelet therapy requirements. Balloon-assisted coiling (BAC) has been well described for this purpose, most commonly using a 2-microcatheter technique, with a balloon microcatheter protecting the aneurysm neck and a coiling microcatheter used to embolize the aneurysm.1,2 However, the availability of advanced double-lumen balloon microcatheters with coiling markers allows for the use of a single-microcatheter technique in select instances.3 We present the case of a patient presenting with a ruptured wide-necked posterior communicating artery aneurysm with a large posterior communicating artery arising from the neck. The aneurysm dome had sufficient height to allow BAC using a single balloon microcatheter, which was used to protect the posterior communicating artery at the neck and deploy coils in the aneurysm dome. The aneurysm was intentionally subtotally coiled and the patient was retreated with a flow-diverting stent later during the same hospitalization (Video 1). Partial coiling followed by later flow diversion is a pragmatic strategy in wide-necked ruptured aneurysms,4 and use of a single balloon microcatheter for BAC can be useful in certain situations.

Assessment of balloon remodeling techniques in endovascular treatment of wide-neck intracranial aneurysms (WN-IAs)

OBJECTIVES

To evaluate the clinical, technical, and angiographic results in endovascular management of wide-neck intracranial aneurysms (WN-IAs) using the balloon-remodeling technique.

METHODS

This study was a prospective, single-center study that was carried out over a period of three years from January 2019 to December 2021 at the Neuro-Interventional Unit at our hospital. Patients who presented with WNIAs and were eligible for endovascular treatment using the balloon-remodeling approach were included in the study.

RESULTS

We included 37 patients with a mean age of 49.7 ± 12.3 years. About 91.9% of the participants had SAH, 5.4% had unruptured aneurysms, and 2.7% had intracranial hemorrhage. The mean time to treatment was 6.97 ± 7.35 days, the mean aneurysm diameter was 5.7 ± 1.7 mm, and the mean neck diameter was 3.8 ± 1.0 mm. The majority of the patients had a dom-to-neck ratio of less than 2 (89.2%). We have used hyper form balloons in 48.6%, hyper glide in 43.2%, Copernic balloons in 5.4%, and eclipse in 2.7%. According to the Raymond-Roy occlusion classification, 86.5% of the patients had complete obliteration, 10.8% had residual neck, and 2.7% had a residual aneurysm. Almost 91.9% had no complications, 2.7% had ischemia, and 5.4% had mild rupture by wire, treated by 5 min hyperinflation of the balloon till hemorrhage stopped.

CONCLUSIONS

Balloon-assisted detachable coiling is an important option in the treatment of WN-IAs. We found that this technique allowed safe and efficient treatment of aneurysms when conventional treatment had failed due to WN. Endovascular coiling using the balloon remodeling technique of wide neck showed a high technical success rate and good short-term clinical outcomes. A good selection of patients with WN-IAs treated by endovascular coiling using balloon remodeling technique and a good selection of materials used help in decreasing the complications.

"Virtual stent" - clinical evaluation and user experience of on-the-fly stent simulation in treatment of cerebral aneurysms

BACKGROUND

Predicting final stent position can be challenging when treating cerebral aneurysms. Third-Party software proved helpful in selecting proper stents in treatment planning. Recent angiographic systems provide basic stent simulation capabilities integrated in the post-processing software to simulate stent position. Goal of this analysis was to evaluate the simulation process and correlation with definite stent position.

MATERIALS AND METHODS

Thirty-three datasets with fusiform (n = 10) and saccular (n = 23) aneurysms, treated with stent or flow-diverter, were processed. A "virtual stent" of the same (nominal) size was simulated and its position was compared to the treatment result. Simulated length was rated in five grades (too short, shorter, equal, longer, too long), with regard to side-branches, anchoring zone etc. Simulation quality (centerline recognition/adherence to vessel margins) was rated in three grades (no, minor or major corrections required).

RESULTS

Simulation was successful in 32/33 cases (97%), with one abortive attempt (3%). In 27/33 simulations (82%), there was no need for centerline refinement. Minor corrections were necessary in four and major corrections in two cases. Simulated nominal length was rated "equal" in 14/33 (42%) cases and "shorter" or "longer" - but within acceptable range - in each 9/33 (27%) cases.

CONCLUSION

Basic stent simulation tools available with genuine angiographic workplace software can provide good simulation capabilities without need for third-party equipment. They can facilitate treatment planning and help to avoid shortage of devices. Yet, lack of calculation of foreshortening in large vessel diameters leaves the user to rely on their experience to account for device-specific properties.

Feasibility and Safety of Transradial Aneurysm Embolization: A Systematic Review and Meta-Analysis

OBJECTIVE

Use of the transradial access (TRA) approach for neuroendovascular procedures has been increasing in recent years. Our aim is to assess the feasibility, success rate, and complications associated with TRA for intracranial aneurysm embolization.

METHODS

PubMed, Scopus, and Embase were systematically searched for studies using TRA for intracranial aneurysm embolization. Random-effects models were used to obtain pooled rates of procedural success and complications.

RESULTS

Twenty-four studies comprising 1283 (85.9%) TRA and 122 (8.2%) distal TRA aneurysm embolization procedures were included. The pooled success rate of the 18 studies in the meta-analysis was 93.5% (95% confidence interval [CI], 91.1%-95.8%). The pooled thromboembolic complication rate was 0.5% (95% CI, 0.1%-0.9%), the hemorrhagic complication rate was 0.5% (95% CI, 0.1%-0.9%), and the access site complication rate was 0.8% (95% CI, 0.3%-1.3%). One study (4.3%) used exclusively a 7-French guide catheter, and most used a 6-French guide catheter (22 of 23 studies, 95.7%), which was further incorporated as part of a triaxial configuration through a sheathless 8-French system in 4 studies (17.4%), 7-French guide catheter in 2 studies (8.7%), and 8-French sheath in 1 study (4.3%). The embolization techniques used were flow diverter placement in 451 cases (39.1%), coiling in 376 (32.6%), stent-assisted coiling in 127 (11.0%), balloon-assisted coiling in 104 (9.0%), Woven EndoBridge system in 50 (4.3%), and flow diverter placement plus coiling in 42 (3.6%).

CONCLUSIONS

Treating intracranial aneurysms using various embolization techniques through TRA is feasible and associated with low access site and intraoperative complications.

Endovascular therapy versus microsurgical clipping of unruptured wide-neck aneurysms: a prospective multicenter study with propensity score analysis

OBJECTIVE

Numerous techniques have been developed to treat wide-neck aneurysms (WNAs), each with different safety and efficacy profiles. Few studies have compared endovascular therapy (EVT) with microsurgery (MS). The authors' objective was to perform a prospective multicenter study of a WNA registry using rigorous outcome assessments and to compare EVT and MS using propensity score analysis (PSA).

METHODS

Unruptured, saccular, not previously treated WNAs were included. WNA was defined as an aneurysm with a neck width ≥ 4 mm or a dome-to-neck ratio (DTNR) < 2. The primary outcome was modified Rankin Scale (mRS) score at 1 year after treatment (good outcome was defined as mRS score 0-2), as assessed by blinded research nurses and compared with PSA. Angiographic outcome was assessed using the Raymond scale with core laboratory review (adequate occlusion was defined as Raymond scale score 1-2).

RESULTS

The analysis included 224 unruptured aneurysms in the EVT cohort (n = 140) and MS cohort (n = 84). There were no differences in baseline demographic characteristics, such as proportion of patients with good baseline mRS score (94.3% of the EVT cohort vs 94.0% of the MS cohort, p = 0.941). WNA inclusion criteria were similar between cohorts, with the most common being both neck width ≥ 4 mm and DTNR < 2 (50.7% of the EVT cohort vs 50.0% of the MS cohort, p = 0.228). More paraclinoid (32.1% vs 9.5%) and basilar tip (7.1% vs 3.6%) aneurysms were treated with EVT, whereas more middle cerebral artery (13.6% vs 42.9%) and pericallosal (1.4% vs 4.8%) aneurysms were treated with MS (p < 0.001). EVT aneurysms were slightly larger (p = 0.040), and MS aneurysms had a slightly lower mean DTNR (1.4 for the EVT cohort vs 1.3 for the MS cohort, p = 0.010). Within the EVT cohort, 9.3% of patients underwent stand-alone coiling, 17.1% balloon-assisted coiling, 34.3% stent-assisted coiling, 37.1% flow diversion, and 2.1% PulseRider-assisted coiling. Neurological morbidity secondary to a procedural complication was more common in the MS cohort (10.3% vs 1.4%, p = 0.003). One-year mRS scores were assessed for 218 patients (97.3%), and no significantly increased risk of poor clinical outcome was found for the MS cohort (OR 2.17, 95% CI 0.84-5.60, p = 0.110). In an unadjusted direct comparison, more patients in the EVT cohort achieved a good clinical outcome at 1 year (93.4% vs 84.1%, p = 0.048). Final adequate angiographic outcome was superior in the MS cohort (97.6% of the MS cohort vs 86.5% of the EVT cohort, p = 0.007).

CONCLUSIONS

Although the treatments for unruptured WNA had similar clinical outcomes according to PSA, there were fewer complications and superior clinical outcome in the EVT cohort and superior angiographic outcomes in the MS cohort according to the unadjusted analysis. These results may be considered when selecting treatment modalities for patients with unruptured WNAs.

Endovascular Therapy Versus Microsurgical Clipping of Ruptured Wide Neck Aneurysms (EVERRUN Registry): a multicenter, prospective propensity score analysis

OBJECTIVE

Randomized controlled trials have demonstrated the superiority of endovascular therapy (EVT) compared to microsurgery (MS) for ruptured aneurysms suitable for treatment or when therapy is broadly offered to all presenting aneurysms; however, wide neck aneurysms (WNAs) are a challenging subset that require more advanced techniques and warrant further investigation. Herein, the authors sought to investigate a prospective, multicenter WNA registry using rigorous outcome assessments and compare EVT and MS using propensity score analysis (PSA).

METHODS

Untreated, ruptured, saccular WNAs were included in the analysis. A WNA was defined as having a neck ≥ 4 mm or a dome/neck ratio (DNR) < 2. The primary outcome was the modified Rankin Scale (mRS) score at 1 year posttreatment, as assessed by blinded research nurses (good outcome: mRS scores 0-2) and compared using PSA.

RESULTS

The analysis included 87 ruptured aneurysms: 55 in the EVT cohort and 32 in the MS cohort. Demographics were similar in the two cohorts, including Hunt and Hess grade (p = 0.144) and modified Fisher grade (p = 0.475). WNA type inclusion criteria were similar in the two cohorts, with the most common type having a DNR < 2 (EVT 60.0% vs MS 62.5%). More anterior communicating artery aneurysms (27.3% vs 18.8%) and posterior circulation aneurysms (18.2% vs 0.0%) were treated with EVT, whereas more middle cerebral artery aneurysms were treated with MS (34.4% vs 18.2%, p = 0.025). Within the EVT cohort, 43.6% underwent stand-alone coiling, 50.9% balloon-assisted coiling, 3.6% stent-assisted coiling, and 1.8% flow diversion. The 1-year mRS score was assessed in 81 patients (93.1%), and the primary outcome demonstrated no increased risk for a poor outcome with MS compared to EVT (OR 0.43, 95% CI 0.13-1.45, p = 0.177). The durability of MS was higher, as evidenced by retreatment rates of 12.7% and 0% for EVT and MS, respectively (p = 0.04).

CONCLUSIONS

EVT and MS had similar clinical outcomes at 1 year following ruptured WNA treatment. Because of their challenging anatomy, WNAs may represent a population in which EVT's previously demonstrated superiority for ruptured aneurysm treatment is less relevant. Further investigation into the treatment of ruptured WNAs is warranted.

Can further subdivision of the Raymond-Roy classification of intracranial aneurysms be useful in predicting recurrence and need for future retreatment following endovascular coiling?

Background:

The Raymond-Roy classification has been the standard for neck recurrences following endovascular coiling with three grades. Several modified classification systems with subdivisions have been reported in literature but it is unclear whether this adds value in predicting recurrence or retreatment. Our aim is to assess if these subdivisions aid in predicting recurrence and need for retreatment.

Methods:

A retrospective review of all patients undergoing endovascular coiling between 2013 and 2014. Patients requiring stent assistance or other embolization devices were excluded from the study. The neck residue was graded at time of coiling on the cerebral angiogram and subsequent 6, 24, and 60 months MRA. Correlation between grade at coiling and follow-up with need for subsequent retreatment was assessed.

Results:

Overall, 17/200 (8.5%) cases required retreatment within 5 years of initial coiling. 4/130 (3.1%) required retreatment within 5 years with initial Grade 0 at coiling, 6/24 cases (25%) of those Grade 2a, 4/20 cases (20%) Grade 2b, 3/8 (38%) Grade 3, and none of those with Grade 1. Large aneurysms ≥11 mm had an increased risk of aneurysm recurrence and retreatment. About 9.7% of ruptured aneurysms required retreatment versus 4.4% for unruptured. About 55% of carotid ophthalmic aneurysms were retreated.

Conclusion:

Although the modified classification system was significantly predictive of progressive recurrence and need for retreatment, no significant difference between the subdivisions of Grade 2 was observed. Similar predictive value was seen when using the Raymond-Roy classification compared to the new modified, limiting the usefulness of the new system in clinical practice.

Endovascular Management of Hemorrhagic Stroke

Significant advances in endovascular neurosurgery tools, devices, and techniques are changing the approach to the management of acute hemorrhagic stroke. The endovascular treatment of intracranial aneurysms emerged in the early 1990s with Guglielmi detachable coils, and since then, it gained rapid popularity that surpassed open surgery. Stent-assisted coiling and balloon remodeling techniques have made the treatment of wide-necked aneurysms more durable. With the introduction of flow diverters and flow disrupters, many aneurysms with complex geometrics can now be reliably managed. Arteriovenous malformations and fistulae can also benefit from endovascular therapy by embolization using n-butyl cyanoacrylate (NBCA), Onyx, polyvinyl alcohol (PVA), and coils. In this article, we describe the role of endovascular treatment for the most common causes of intracerebral and subarachnoid hemorrhages, particularly ruptured aneurysms and vascular malformations.

Patient and aneurysm factors associated with aneurysm recanalization after coiling

BACKGROUND

One limitation of the endovascular treatment of intracranial aneurysms is aneurysm recanalization. The Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) study is a prospective multicenter cohort study evaluating the factors associated with recanalization after endovascular treatment.

METHODS

The current analysis is focused on patients treated by coiling or balloon-assisted coiling (BAC). Postoperative, mid-term vascular imaging, and evolution of aneurysm occlusion were independently evaluated by two neuroradiologists. A 3-grade scale was used for aneurysm occlusion (complete occlusion, neck remnant, and aneurysm remnant) and for occlusion evolution (improved, stable, and worsened). Recanalization was defined as any worsening of aneurysm occlusion.

RESULTS

Between December 2013 and May 2015, 16 French neurointerventional departments enrolled 1289 patients. A total of 945 aneurysms in 908 patients were treated with coiling or BAC. The overall rate of aneurysm recanalization at mid-term follow-up was 29.5% (95% CI 26.6% to 32.4%): 28.9% and 30.3% in the coiling and BAC groups, respectively. In multivariate analyses factors independently associated with recanalization were current smoking (36.6% in current smokers vs 24.5% in current non-smokers (OR 1.8 (95% CI 1.3 to 2.4); p=0.0001), ruptured status (31.9% in ruptured aneurysms vs 25.1% in unruptured (OR 1.5 (95% CI 1.1 to 2.1); p=0.006), aneurysm size ≥10 mm (48.8% vs 26.5% in aneurysms <10 mm (OR 2.6 (95% CI 1.8 to 3.9); p<0.0001), wide neck (32.1% vs 25.8% in narrow neck (OR 1.5 (95% CI 1.1 to 2.1); p=0.02), and MCA location (34.3% vs 28.3% in other locations (OR 1.5 (95% CI 1.0 to 2.1); p=0.04).

CONCLUSIONS

Several factors are identified by the ARETA study as playing a role in aneurysm recanalization after coiling: current smoking, aneurysm status (ruptured), aneurysm size (≥10 mm), neck size (wide neck), and aneurysm location (middle cerebral artery). This finding has important consequences in clinical practice.

TRIAL REGISTRATION NUMBER

URL: http://www.clinicaltrials.gov; Unique Identifier: NCT01942512.

Microcatheter Stabilization Technique Using Partially Inflated Balloon for Coil Embolization of Paraclinoid Aneurysms

PURPOSE

Coil embolization of paraclinoid aneurysms should be simple, safe, and effective considering the benign nature of the aneurysm. Here, we present a microcatheter stabilization technique using a partially inflated balloon for the treatment of paraclinoid aneurysms.

MATERIALS AND METHODS

This retrospective study included 58 patients who underwent balloon-assisted coiling (BAC) for unruptured paraclinoid aneurysms at a tertiary neuro-intervention center between January 2019 and March 2020. We applied a technique to stabilize the microcatheter's position using the modified BAC technique in paraclinoid aneurysms showing various projections around the ophthalmic curve of the internal carotid artery. The basic concept of the technique is to place a partially inflated balloon just distal to the aneurysm neck and support the distal curve of the microcatheter using the proximal bottom of the balloon. Immediate radiological outcomes were analyzed, and clinical outcomes were evaluated with modified Rankin Scale (mRS) scores.

RESULTS

The BAC was successfully performed in 51 of 58 patients (88%). We treated the remaining 7 patients by switching to stent-assisted coiling. We obtained a 37% mean packing density resulting in favorable occlusion in all 58 aneurysms (complete occlusion in 35 and residual neck in 23). There were no intraprocedural thromboembolic or hemorrhagic events except one that revealed an asymptomatic infarction after the procedure (1.7%). Magnetic resonance angiography follow-up was performed in 37 patients at an average of 11.8 months, in which 11 minor recurrences (29.7%) were found. There was no major recurrence nor retreatment. The mRS score was 0 in all patients during a mean follow-up of 17.7 months (range, 12-25 months).

CONCLUSION

The modified balloon-assisted coiling technique using a partially inflated balloon was safe and effective and could serve as an option for treating paraclinoid aneurysms.

Unassisted and multiple microcatheter coiling of distal basilar aneurysms: Outcomes and literature review

PURPOSE

The best treatment for distal basilar artery aneurysms is controversial. We aimed to review our single-centre experience with coil embolisation of aneurysms at this location and compare it with the surgical and endovascular literature.

METHODS

Forty-two aneurysms in a distal basilar location in 42 consecutive patients (15 ruptured and 27 unruptured) were treated endovascularly from 2010 to 2015. Unassisted single and multiple microcatheter coil embolisation alone was used in all cases. We studied our immediate and long-term anatomical results, operative complications, and outcome.

RESULTS

The immediate angiographic results showed complete occlusion in 34 (81%), a neck remnant in seven (16.6%) and a residual aneurysm in one patient (2.4%). There were two thromboembolic events (4.7%) without clinical sequelae; therefore, the operative morbidity and mortality were zero.Three patients with ruptured aneurysms (7.1%) died due to complicated vasospasm. Thirty-nine patients (93%) had clinical and MR imaging follow-up (mean 32.3 months ± 18.6, range from 12 to 66 months). There was recanalization in 30.8% with a retreatment rate of 15.3% and no new bleedings. The aneurysm size was the most important predictor of early anatomical outcome and recurrence.

CONCLUSION

Unassisted and multiple microcatheter coiling is a safe treatment for distal basilar aneurysms. Early anatomical results and recurrence depend on the aneurysm size. Morbidity and mortality are lower and recurrence rates are higher in comparison with clipping or other adjunctive endovascular techniques.

Endovascular Treatment of Intracranial Aneurysms

Traditionally, surgical clipping was the only available treatment modality for intracranial aneurysms. However, in the last few decades, the endovascular therapy of intracranial aneurysms (IAs) has seen a tremendous evolution and development. From coiling to flow diversion and flow disruptor devices, endovascular treatment modalities have increased in number and received broader indications throughout the years. In this review article, the treatment modalities for the endovascular management of IAs are presented, emphasizing newer devices and technologies.

Stabilizing interventional instruments in the cardiovascular system: A classification of mechanisms

Positioning and stabilizing a catheter at the required location inside a vessel or the heart is a complicated task in interventional cardiology. In this review we provide a structured classification of catheter stabilization mechanisms to systematically assess their challenges during cardiac interventions. Commercially available, patented, and experimental prototypes of catheters were classified with respect to their stabilizing mechanisms. Subsequently, the classification was used to define requirements for future cardiac catheters and persisting challenges in catheter stabilization. The classification showed that there are two main stabilization mechanisms: surface-based and volume-based. Surface-based mechanisms apply attachment through surface anchoring, while volume-based mechanisms make use of locking through shape or force against the vessel or cardiac wall. The classification provides insight into existing catheter stabilization mechanisms and can possibly be used as a tool for future design of catheter stabilization mechanisms to keep the catheter at a specific location during an intervention. Additionally, insight into the requirements and challenges for catheter stabilization inside the heart and vasculature can lead to the development of more dedicated systems in the future, allowing for intervention- and patient-specific instrument manipulation.

Evaluation of Surgical Clipping and Endovascular Coiling on Oculomotor Nerve Palsy Caused by Internal Carotid Artery Aneurysm

Objectives: Internal carotid artery (ICA) aneurysm often leads to oculomotor nerve palsy (ONP) that impairs eye movement. Currently, microsurgical clipping and endovascular coiling are the two major options to treat ONP. The purpose of the current study is to compare the clinical outcomes of the two methods in patients with ONP caused by ICA aneurysm. Patients and Methods: In the present study, we assessed the prognostic factors and recovery outcomes of a total of 90 ICA aneurysm-induced ONP patients, where 50 of them were treated with microsurgical clipping and 40 of them were treated with endovascular coiling. Within the endovascular coiling group, 20 of the patients were treated with balloon-assisted coiling and the other 20 were treated with stent-assisted coiling. Results: Overall, we achieved a 59% (53 out of 90) full recovery rate. Both surgical clipping and endovascular coiling treatment methods achieved similar recovery outcomes in the tested patients. However, within the endovascular coiling group, balloon-assisted coiling treatment demonstrated a significantly higher full recovery rate (17 out of 20) compared to stent-assisted coiling treatment (eight out of 20). Conclusion: In general, no significant difference was identified between the surgical and coiling treatments, and both procedures were considered as beneficial for ICA aneurysm-induced ONP.

The Woven EndoBridge (WEB) Versus Conventional Coiling for Treatment of Patients with Aneurysmal Subarachnoid Hemorrhage: Propensity Score-Matched Analysis of Clinical and Angiographic Outcome Data

OBJECTIVE

Conventional coiling is standard for treatment of ruptured intracranial aneurysms. We compared clinical and angiographic outcomes between intrasaccular flow disruption with the Woven EndoBridge (WEB) and conventional coiling in patients with aneurysmal subarachnoid hemorrhage (aSAH) using a propensity score-matched analysis.

METHODS

This is a retrospective study of consecutive patients with aSAH treated with the WEB or conventional coiling between 2010 and 2019. Baseline characteristics, procedural complications, angiographic results, and functional outcome were compared between both groups.

RESULTS

Fifty-two patients treated with the WEB and 236 patients treated by coiling were included. The WEB group was characterized by a higher patient age (P = 0.024), a wider aneurysm neck (P < 0.001), and more frequent location at the posterior circulation (P = 0.004). Procedural complications were comparable between WEB (19.2%) and coiling (22.7%, P = 0.447). In-hospital mortality rates were higher in the coiling group (WEB: 5.8%, coiling: 17.8%; P = 0.0034). Favorable outcome (modified Rankin scale ≤2) was obtained in 51.3% after WEB embolization and in 55.0% after coiling (P = 0.653). Retreatment was performed in 26.4% of patients after WEB and in 25.8% after coiling (P = 0.935). Propensity score analysis confirmed these results and revealed higher adequate occlusion rates at midterm follow-up for WEB-treated aneurysms (WEB: 93.9%, coiling: 76.2%, P = 0.058).

CONCLUSIONS

Compared with conventional coiling, aSAH patients treated with the WEB have a similar clinical and potentially improved angiographic outcome at midterm follow-up. The WEB might be considered as an alternative to conventional coiling for the treatment of RIAs, in particular for those with wide-necked and thus challenging anatomy.

Comparison of Treatment Results by Coil Embolization Procedures for Ruptured Cerebral Aneurysms

Objective

In coil embolization of ruptured cerebral aneurysms, intraoperative cerebral aneurysm re-rupture and thromboembolism are of concern. A good embolic condition can be expected by adjunctive techniques, but there is an increased risk of complications. We investigated the treatment results by coil embolization procedures for ruptured cerebral aneurysms.

Methods

Between January 2016 and December 2019, 75 ruptured saccular cerebral aneurysms were treated by coil embolization at our hospital. The background factors, results of aneurysm embolization, intraoperative re-rupture, symptomatic cerebral embolism, and other factors were investigated retrospectively. We compared and examined these factors based on the procedure.

Results

The mean age was 62.8 and there were 57 female patients (76.0%). The single catheter technique (SCT) was used in 44 cases (58.7%) and the adjunctive technique was used in 31 cases (41.3%). Complete obliteration (CO) was achieved in 24 cases (32.0%), there was a neck remnant (NR) in 23 (30.7%), body filling (BF) was observed in 28 (37.3%), intraoperative re-rupture occurred in 7 (9.3%), and symptomatic cerebral embolism developed in 6 (8.0%), but no postoperative re-rupture was observed. Retreatment was required in only three cases of SCT. On comparison by procedure, the incidence of symptomatic cerebral embolism was significantly lower in SCT group than in the adjunctive technique group (2.3% vs 16.1%, p = 0.04).

Conclusion

Among the cases of coil embolization for ruptured cerebral aneurysms at our hospital, SCT resulted in a lower incidence of symptomatic cerebral embolism than adjunctive techniques. It is essential to select an appropriate procedure in each case by understanding the characteristics of each procedure.

Comparing Occlusive Balloon Performance Using 3-Dimensional Printed Models of Intracranial Aneurysmal Defects

OBJECTIVE

Balloon remodeling microcatheters are essential in assisting endovascular coiling of brain aneurysms, but the performance and pressure requirements of different balloon types when used in aneurysmal defects are currently unknown.

METHODS

We used Tinkercad (Autodesk, Montreal, Quebec) to create model vessels with aneurysmal defects and 3-dimensionally printed these designs with polylactic acid using the Ultimaker2 (Ultimaker, Geldermalsen, Netherlands). We constructed a pressurized box capable of reaching physiologic pressures that housed our vessels and then tested compliant remodeling balloons under fluoroscopy from 3 manufacturers: Hyperglide (Medtronic, Minneapolis, Minnesota, USA), Transform (Stryker Neurovascular, Fremont, California, USA), and Scepter C (Microvention, Tustin, California, USA). Each balloon was inflated to a nominal and supranominal point at each defect, and at each inflation the maximum diameter of the balloon and internal balloon pressure were recorded. The Phillips Intellivue (Phillips, Amsterdam, The Netherlands) monitor was adapted for internal balloon pressure monitoring. A multivariate linear regression analysis was performed to model balloon compliance (balloon diameter divided by pressure).

RESULTS

Multivariate regression modeling demonstrated the Scepter balloon had significantly greater compliance compared with both the Hyperglide and Transform balloons (P < 0.001). In addition, we found that Scepter balloons had higher compliance in larger defects compared with the other types of balloons and performance differences based on vessel size.

CONCLUSIONS

Scepter balloons require less pressure compared with their counterparts to adequately deform through model defects, specifically in larger aneurysm necks in smaller vessel diameters. This result could inform operators of optimal balloon type and size when trying to minimize balloon pressure in fragile brain aneurysms.

Wide-neck aneurysms: systematic review of the neurosurgical literature with a focus on definition and clinical implications

OBJECTIVE

Wide-necked aneurysms (WNAs) are a variably defined subset of cerebral aneurysms that require more advanced endovascular and microsurgical techniques than those required for narrow-necked aneurysms. The neurosurgical literature includes many definitions of WNAs, and a systematic review has not been performed to identify the most commonly used or optimal definition. The purpose of this systematic review was to highlight the most commonly used definition of WNAs.

METHODS

The authors searched PubMed for the years 1998-2017, using the terms "wide neck aneurysm" and "broad neck aneurysm" to identify relevant articles. All results were screened for having a minimum of 30 patients and for clearly stating a definition of WNA. Reference lists for all articles meeting the inclusion criteria were also screened for eligibility.

RESULTS

The search of the neurosurgical literature identified 809 records, of which 686 were excluded (626 with < 30 patients; 60 for lack of a WNA definition), leaving 123 articles for analysis. Twenty-seven unique definitions were identified and condensed into 14 definitions. The most common definition was neck size ≥ 4 mm or dome-to-neck ratio < 2, which was used in 49 articles (39.8%). The second most commonly used definition was neck size ≥ 4 mm, which was used in 26 articles (21.1%). The rest of the definitions included similar parameters with variable thresholds. There was inconsistent reporting of the precise dome measurements used to determine the dome-to-neck ratio. Digital subtraction angiography was the only imaging modality used to study the aneurysm morphology in 87 of 122 articles (71.3%).

CONCLUSIONS

The literature has great variability regarding the definition of a WNA. The most prevalent definition is a neck diameter of ≥ 4 mm or a dome-to-neck ratio of < 2. Whether this is the most appropriate and clinically useful definition is an area for future study.

Stent-Assisted Coiling Using Leo+ Baby Stent : Immediate and Mid-Term Results

Background

Stent-assisted coiling is well-established for treatment of cerebral aneurysms. The technique enables treatment of wide-neck, bifurcation and recurrent aneurysms with high packing rates. While described in extenso for laser cut stents, the results of patients treated with the Leo+ Baby (Balt, Montmorency, France) braided microstent are presented.

Material and Methods

Patients were included if treated with a Leo+ Baby and with digital subtraction angiography (DSA) follow-up available of at least 6 months. Data were evaluated for successful deployment, aneurysm occlusion according to the modified Raymond-Roy classification (MRRC), stent patency and procedure-related morbidity and mortality.

Results

A total of 81 patients were included and Leo+ Baby deployment was successful in all cases. Coils were used in 80 cases. In 1 case 2 stents were used stent-in-stent without additional coiling. Initial aneurysm occlusion rates were MRRC_i1 51.9%, MRRC_i2 11.1%, MRRC_i3a 24.7% and MRRC_i3b 12.3%. Occlusion rates after 6 months were MRRC_6m1 78.9%, MRRC_6m2 3.9%, MRRC_6m3a 6.6% and MRRC_6m3b 10.5%. Procedure-related morbidity was 1 case of acute stent thrombosis successfully treated with tirofiban and 1 case with transient hemiparesis due to stent thrombosis after 4 months. There was 1 case of coil-associated subarachnoid hemorrhage (SAH) which caused prolonged hospitalization. No procedure-related mortality was observed.

Conclusion

The results confirm that stent-assisted coiling with the Leo+ Baby stent is safe and efficient for treatment of wide neck or recurrent cerebral aneurysms. Spontaneous progressive aneurysm occlusion over 6 months supports the theory of considerable flow-modulating effects of Leo+ Baby.

Endovascular Treatment for Cavernous Carotid Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Coiling and flow diversion are established endovascular techniques for treatment of cavernous carotid aneurysms (CCAs). We performed a systematic review of published series on endovascular treatment of CCAs in order to assess the efficacy and safety between coiling and flow diversion.

METHODS

We conducted a computerized search of PubMed, MEDLINE, and Web of Science electronic databases for reports on endovascular treatment of CCAs from 1990 to 2019. Comparisons were made in complete occlusion rate, improvement of symptoms rate and intraoperative complication rate between coiling and flow diversion.

RESULTS

Fourteen studies with 736 patients were included in this systematic review. Five hundred ninety-4 patients underwent coiling, 142 patients underwent flow diversion. The complete occlusion rate in the coiling group was significantly lower than that in the flow division group (odds ratio .37, 95%CI .16-.83, P < .00001), a forest plot did not reveal any significant differences in the improvement of symptoms rate or intraoperative complication rate following coiling and flow diversion. Complete occlusion rate was significantly lower in the coiling group (53%, 95%CI .40-.67) compared with the flow diversion group (74%, 95%CI .55-.94). Improvement of symptoms was significantly lower in the coiling group (54%, 95%CI .46-.63) compared with the flow diversion group (92%, 95%CI .85-.99). Coiling group had lower intraoperative complication rate (9%, 95%CI .06-.12) compared with flow division group (36%, 95%CI .25-.47).

CONCLUSIONS

Compared with coiling, the use of flow diversion for the treatment of CCAs may increase complete occlusion rate, and improvement of symptoms rate, but it also raised intraoperative complication rate. Due to the lack of high quality control research, further randomized controlled trials are needed to verify our conclusions.

Advances in endovascular aneurysm management: coiling and adjunctive devices

Endovascular coil embolisation continues to evolve and remains a valid modality in managing ruptured and unruptured cerebral aneurysms. Technological advances in coil properties, adjunctive devices and interventional techniques continue to improve long-term aneurysm occlusion rates. This review elaborates on the latest advances in next-generation endovascular coils and adjunctive coiling techniques for treating cerebral aneurysms.

Balloon-assisted coiling of intracranial aneurysms using the Eclipse 2L double lumen balloon

BACKGROUND

Eclipse 2L is a new double lumen balloon microcatheter for neurovascular use, with several design features that separate it from previous generation devices. We aimed to report our initial experience of balloon-assisted coiling of intracranial aneurysms using the Eclipse 2L balloon.

MATERIALS AND METHODS

Retrospective single-center review of patients who underwent balloon-assisted coiling with the Eclipse 2L balloon, for ruptured or unruptured intracranial aneurysms between 1 June 2016 and 31 December 2018. Cases with adjunctive use of stents and recurrences of previously embolized aneurysms were excluded. Patient files were used to extract aneurysm characteristics, complications, immediate and long-term results.

RESULTS

We identified 120 patients with 126 aneurysms, of which 83 (65.8%) unruptured. Average aneurysm size was 5.9 mm (standard deviation 3.2 mm), with a dome-to neck-ratio of 1.7 (SD 0.6). Most aneurysms (79.3%) were wide necked. Immediate angiographic exclusion (Raymond-Roy grade I-II) was obtained in 95.1% of cases (81.7% grade I and 13.4% grade II). Procedural morbidity was 3.2% with no procedural mortality. Follow-up imaging was available for 115 aneurysms (91.2%). After an average follow-up period of 8.9 months (SD 7.3 months), 96.5% of aneurysms presented class I-II occlusion. Two aneurysms (1.7%) were retreated during follow-up.

CONCLUSION

Balloon-assisted coiling using the Eclipse 2L double lumen balloon is feasible for aneurysms in a wide range of locations in the anterior and posterior circulation. The angiographic results and complication rates compare favorably with previously published studies.

Effect of Direct Neurologic Evaluation on Outcomes During Treatment of Unruptured Intracranial Aneurysms Under Local Anesthesia

OBJECTIVE

The greatest advantage of local anesthesia (LA) in endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs) is that direct neurologic evaluation can be performed during the procedure, unlike with general anesthesia. However, the usefulness of such direct evaluation has not been established. In this study, we attempted to assess the effects of direct neurologic evaluation by identifying the causes, management, and outcomes of clinical symptoms during the procedure and procedure-related events during EVT under LA.

METHODS

We retrospectively evaluated the medical and radiologic data of 1000 patients (1015 UIAs) who had undergone coil embolization under LA from 2008 to 2016.

RESULTS

Clinical symptoms were identified in 62 patients (6.2%) during the procedure. The symptoms improved during the procedure in 27 of these patients (44%) and after the procedure in another 28 (45%). One month after the procedure, 55 patients (89%) had good outcomes and 7 (11%) had poor outcomes. Procedure-related events occurred in 67 patients (6.7%); of these 67 events, 39 were symptomatic and 28 were asymptomatic. Thirty-five of the 39 symptomatic events (90%) [13 of 13 (100%) ruptures, 6 of 10 (60%) thrombus formations, and 16 of 16 (100%) thromboembolisms] were detected on the basis of clinical symptoms before angiographic changes were identified, and they were managed promptly. All 28 patients with asymptomatic events were managed safely without further complications before symptoms developed.

CONCLUSIONS

We demonstrated that appropriate management of clinical symptoms and procedure-related events under LA led to favorable outcomes of EVT of UIAs.

Residuals, recurrences and re-treatment after endovascular repair of intracranial aneurysms: A retrospective methodological comparison

OBJECTIVE

Incomplete aneurysm occlusions and re-treatment rates of 52 and 10-30%, respectively, have been reported following endovascular treatment of intracranial aneurysms, raising clinical concerns regarding procedural efficacy. We compare residual, recurrence and re-treatment rates subject to different endovascular techniques in both ruptured and unruptured intracranial aneurysms at a comprehensive state-wide tertiary neurovascular centre in Australia.

METHODS

Medical records, procedural and follow-up imaging studies of all patients who underwent endovascular treatment for intracranial aneurysms between July 2010 and July 2017 were reviewed retrospectively. Residuals, recurrences and re-treatment rates were assessed regarding initial aneurysm rupture status and applied endovascular technique: primary coiling, balloon- and stent-assisted coiling and flow diversion.

RESULTS

Among 233 aneurysms, residual, recurrence and re-treatment rates were 27, 11.2 and 9.4%, respectively. Compared with unruptured aneurysms, similar residual and recurrence (p > .05), but higher re-treatment rates (4.5% vs. 19%; p < .001) were found for ruptured aneurysms. Residual, recurrence and re-treatment rates were: 13.3, 16 and 12% for primary coiling; 12, 12 and 10.7% for balloon-assisted coiling; 14.9, 7.5 and 4.5% for stent-assisted coiling; 91.9, 0 and 5.4% for flow diversion. Stent-assistance and flow-diversion were associated with lower recurrence and re-treatment rates, when compared with primary- and balloon-assisted coiling (p < .05).

CONCLUSIONS

Residuals and recurrences after endovascular treatment of intracranial aneurysms are less common than previously reported. Stent assistance and flow diversion seem associated with reduced recurrence- and re-treatment rates, when compared with primary- and balloon-assisted coiling. Restrained use of stents in ruptured aneurysms may be a contributing factor for higher recurrence/retreatment rates compared to unruptured aneurysms.

Comparison of Flow Diversion and Coiling for the Treatment of Unruptured Intracranial Aneurysms

BACKGROUND

To systematically assess the efficacy and safety between flow diversion and coiling for patients with unruptured intracranial aneurysms.

METHODS

Potential academic articles were identified from Cochrane Library, Medline, PubMed, EMBASE, ScienceDirect, and other databases. The time range we retrieved from was the inception of electronic databases to February 2019. Gray studies were identified from the references of included literature reports. STATA version 11.0 was used to analyze the pooled data.

RESULTS

A total of 11 articles (10 retrospective studies and 1 prospective study) were involved in our study. The overall participants of the coiling group were 611, whereas 576 were in the flow diversion group. Our meta-analysis showed that flow diversion was preferable for unruptured intracranial aneurysms as its lower value of total cost per case (weighted mean difference, 5705.906; 95% confidence interval [CI], [4938.536, 6473236]; P < 0.001), fluoroscopy time per case (weighted mean difference, 25.786; 95% CI, 17.169-34.377; P < 0.001), and retreatment rates (odds ratio [OR], 7.127; 95% CI, [3.525, 14.410]; P < 0.001), at the same time, a higher rate of immediate completed occlusion (OR, 0.390; 95% CI, [0.224, 0.680]; P = 0.001) and follow-up completed occlusion (OR, 0.173; 95% CI, [0.080, 0.375]; P < 0.001) was demonstrated in the flow diversion group. There was no difference on intraoperative complication rates (P = 0.070), procedure-related mortality (P = 0.609) and rupture rates (P = 0.408), modified Rankin Scale (mRS) 0-2 at discharge (P = 0.077), and mRS 0-2 at follow-up (P = 0.484).

CONCLUSIONS

The use of flow diversion for the treatment of unruptured intracranial aneurysms may reduce total cost per case, fluoroscopy time per case, retreatment rates, and increases immediate completed occlusion and follow-up completed occlusion rates without affecting the results of mRS and intraoperative complication.

Balloon-assisted coiling of cerebral aneurysms with the dual-lumen Scepter XC balloon catheter: Experience at two high-volume centers

BACKGROUND

The Scepter XC is a dual-lumen balloon catheter that accommodates a 0.014-inch microwire and can be used for balloon-assisted coiling of cerebral aneurysms. We describe our experience with the use of this device.

METHODS

Two high-volume institution neurointerventional databases were retrospectively reviewed for cerebral aneurysms treated with balloon-assisted coiling using the Scepter XC balloon catheter. Patient demographics, aneurysm characteristics, and procedural details were recorded. Major procedure-related neurologic complications were defined as events that caused an increase in modified Rankin Scale that persisted for more than 1 week after the procedure. Follow-up aneurysm occlusion was assessed using the Raymond-Roy classification.

RESULTS

During the study period, 231 aneurysms were treated in 219 patients (152 women, 67 men) with a mean age of 58.4 ± 12.2 years. Mean aneurysm size was 6.1 ± 3.1 mm, with a mean neck diameter of 3.1 ± 1.3 mm. In total, 77.5% of aneurysms were wide necked, and 39.8% were treated in the setting of subarachnoid hemorrhage. The major complication rate was 0.9% (2/231) per treated aneurysm, including one stroke and one death related to intraoperative aneurysm rupture. Excluding patients who died, angiographic follow up was available for 85.3% (191/224) of aneurysms. During a mean follow up of 17.4 ± 13.0 months (range, 1.7-66.5 months), Raymond-Roy 1 and 2 occlusion rates were 56.5% (108/191) and 35.6% (68/191), respectively. The retreatment rate was 12.6% (24/191).

CONCLUSION

Our experience using the coaxial dual-lumen Scepter XC for balloon-assisted coiling demonstrates acceptable aneurysm occlusion and complication rates.

Endovascular Metal Devices for the Treatment of Cerebrovascular Diseases

Cerebrovascular disease involves various medical disorders that obstruct brain blood vessels or deteriorate cerebral circulation, resulting in ischemic or hemorrhagic stroke. Nowadays, platinum coils with or without biological modification have become routine embolization devices to reduce the risk of cerebral aneurysm bleeding. Additionally, many intracranial stents, flow diverters, and stent retrievers have been invented with uniquely designed structures. To accelerate the translation of these devices into clinical usage, an in-depth understanding of the mechanical and material performance of these metal-based devices is critical. However, considering the more distal location and tortuous anatomic characteristics of cerebral arteries, present devices still risk failing to arrive at target lesions. Consequently, more flexible endovascular devices and novel designs are under urgent demand to overcome the deficiencies of existing devices. Herein, the pros and cons of the current structural designs are discussed when these devices are applied to the treatment of diseases ranging broadly from hemorrhages to ischemic strokes, in order to encourage further development of such kind of devices and investigation of their use in the clinic. Moreover, novel biodegradable materials and drug elution techniques, and the design, safety, and efficacy of personalized devices for further clinical applications in cerebral vasculature are discussed.

Safety and efficiency of the fifth generation Woven EndoBridge device: technical note

BACKROUND

The treatment of wide neck bifurcation aneurysms remains challenging despite the introduction of new techniques (Y stenting, waffle cone technique, or flow diverter stents). The Woven EndoBridge (WEB) device is an innovative solution for this type of cerebral aneurysm. A new WEB 17 is now available and has been designed to offer smaller sized devices to optimize navigability and delivery.

METHODS

Between February 2017 and April 2018 all patients treated with the WEB 17 device in our center were retrospectively reviewed. 25 patients with 28 non-ruptured aneurysms were identified and analyzed. Three patients with two aneurysms both treated with the WEB device were identified.

RESULTS

The device was successfully deployed in all cases. Procedure related morbidity was 4% and mortality was 0%. In one case, a delayed postprocedural thromboembolic event occurred owing to device protrusion. Technical success, complications, angiographic outcomes, procedural data, and follow-ups are reported. The modified Rankin Scale score at discharge was 0 for 24 patients (96%). At the 3, 6, or 9 month follow-up, angiograms were taken of 21 of the 25 patients (84%) (24 of 28 aneurysms had been controlled); 3 patients (3 aneurysms) did not receive angiographic follow-up at the time of submission of this work. Complete occlusion was achieved in 22 of 24 aneurysms (91.66%), and 2 of 24 aneurysm (8.33%) showed a neck remnant.

CONCLUSIONS

The WEB 17 is safe and technically feasible, according to this retrospective single center analysis. For very small bifurcation aneurysms, the WEB 17 seems to have lower complication rates than stent assisted techniques. However, further studies are needed to evaluate the complication rate and long term efficiency.

Intracranial Aneurysm: Diagnostic Monitoring, Current Interventional Practices, and Advances

PURPOSE OF REVIEW

Cerebral aneurysms are commonly diagnosed incidentally with non-invasive neuro-imaging modalities (i.e., brain MRA and/or head CTA). The first decision to be made in the management of patients with unruptured cerebral aneurysms is to determine if the aneurysm should undergo treatment as any intervention carries a risk of morbidity and mortality.

RECENT FINDINGS

The multiple risk factors that are associated with increased risk of aneurysm rupture should be evaluated (size, shape, and location of aneurysm; history of hypertension and cigarette smoking and family history of cerebral aneurysms). With the advent and rapid evolution of less traumatic neuro-endovascular surgery techniques in the past two decades, many more patients are undergoing treatment of cerebral aneurysms. The neuro-endovascular surgeon has multiple options for the treatment of aneurysms including coiling, with or without balloon/stent assistance, and flow diversion. A number of intrasaccular devices for the neuro-endovascular treatment of cerebral aneurysms are being evaluated. The percentage of patients with cerebral aneurysms treated with craniotomy and clip ligation is decreasing. This is controversial as it has direct impact in neurosurgical training and the aneurysms that are usually recommended for microsurgical clipping are the ones with challenging anatomy that cannot be treated safely with endovascular approaches. The best outcomes are achieved with management by experienced, high-volume practitioners at specialized cerebrovascular treatment centers that consist of individuals with dedicated training in neuro-endovascular surgery as well as individuals trained in open cerebrovascular neurosurgery.

Analysis of Wide-Neck Aneurysms in the Barrow Ruptured Aneurysm Trial

BACKGROUND

Ruptured wide-neck aneurysms (WNAs) are difficult to treat and few publications have compared clipping to coiling.

OBJECTIVE

To determine, using Barrow Ruptured Aneurysm Trial (BRAT) data: (1) How many aneurysms had a wide neck? (2) Did wide-neck status influence treatment? (3) How did clipping compare to coiling for WNAs?

METHODS

A post hoc analysis was conducted of saccular WNAs in the BRAT. A WNA was defined as maximum neck width ≥ 4 mm or maximum aneurysm dome-diameter–to–neck-width ratio < 2. Both intent-to-treat and as-treated analyses were performed.

RESULTS

Of the 327 patients analyzed, 177 (54.1%) had a WNA. WNAs were more likely to occur in older patients (P = .03) with worse presenting clinical grade (P = .02), were more likely to arise from the middle cerebral artery, basilar tip, or internal carotid artery other than the junction with the posterior communicating artery (P = .001) and were associated with worse clinical outcomes at all time points (P ≤ .01). WNAs were equally distributed in assigned treatment groups (clip 56.6% vs coil 51.8%; P = .38), but were overrepresented in the actual clipping group (clip 62.4% vs coil 37.6%, P < .001). Most patients (76.7%) in the coil-to-clip crossover group had a WNA. Comparing clipping to coiling, there was no difference in clinical outcomes at any time point in either analysis (P ≥ .33). The aneurysm obliteration rate was lower (P < .001) and the retreatment rate higher (P < .001) in the actual coiling group.

CONCLUSION

Wide-neck status significantly impacted treatment strategy in the BRAT, favoring clipping. Clipping and coiling of ruptured WNAs resulted in statistically similar long-term clinical outcomes.

10.1093/neuros/nyy439 Video Abstract 10.1093.neuros.nyy439 5850292551001

Balloon remodeling-assisted Woven EndoBridge technique: description and feasibility for complex bifurcation aneurysms

Background

Woven EndoBridge (WEB) deployment remains challenging in aneurysms with a complex shape or orientation.

Objective

To show that embolization of wide-neck bifurcation aneurysms using the WEB device balloon remodeling-assisted technique is a feasible and elegant endovascular solution compared with other techniques, such as balloon remodeling or stent-assisted coiling.

Materials and methods

10 cases (10 aneurysms in 9 patients) of balloon remodeling-assisted WEB treatment of unruptured complex bifurcation aneurysms were treated in our institution and retrospectively analyzed. Details of clinical presentations, technical details, perioperative and postoperative complications, and outcomes were collected. Immediate and long-term angiographic results were also evaluated.

Results

Aneurysms included six middle cerebral artery aneurysms, one anterior communicating artery aneurysm, one posterior communicating artery aneurysm, one basilar artery aneurysm, and one T-shaped carotid aneurysm. Mean dome width was 6.55 mm, mean neck size 4.5 mm, mean height 4.79 mm, and mean dome-to-neck ratio was 1:1.46. Treatment was performed exclusively with the balloon remodeling-assisted WEB technique in all cases. The device was successfully deployed in every case. Periprocedural thromboembolic or hemorrhagic events did not occur. The modified Rankin Scale score at discharge was 0 for all patients. At mid-term or long-term angiographic follow-up, adequate occlusion was observed in 7 aneurysms from 8 controlled cases (87.5%), and one patient (2 aneurysms) did not have angiographic follow-up.

Conclusion

The balloon remodeling-assisted WEB technique seems to be a safe and effective solution for endovascular treatment of unruptured wide-neck bifurcation aneurysms with specific complex anatomy. However, further studies are needed to evaluate the rate of complications and long-term efficacy.

Evaluation of ischemic lesion prevalence after endovascular treatment of intracranial aneurysms, as documented by 3-T diffusion-weighted imaging: a 2-year, single-center cohort study

OBJECTIVE

Even though published data exist concerning the prevalence of ischemic lesions detected by diffusion-weighted imaging (DWI) following endovascular treatment of intracranial aneurysms, a single-center cross-evaluation of the different endovascular techniques has been lacking. The authors sought to prospectively evaluate the prevalence and clinical significance of ischemic lesions occurring after endovascular treatment of intracranial aneurysms and to compare the safety and effectiveness of a broad spectrum of currently accepted endovascular techniques in a single-center setting.

METHODS

This was a prospective cohort study involving consecutive patients treated for intracranial aneurysms exclusively by endovascular means, excluding treatments in the acute rupture phase, in a center featuring an endovascular-only treatment policy for intracranial aneurysms. All patients underwent MRI, including a 3-directional DWI sequence, before treatment, 24 hours postprocedure, and 6 months following endovascular embolization. Selective angiography was performed at 6 months’ follow-up.

RESULTS

From January 2012 through December 2013, 164 aneurysms were treated in 128 consecutive patients. Endovascular techniques included coiling (14.6%), balloon-assisted coiling (20.1%), stent-assisted coiling (3.7%), low-profile stent-assisted coiling, flow diversion (38.4%), and very complex treatments (6.1%) involving 2 stents in Y or T configurations. On postprocedure MRI, the rates of occurrence of new DWI-positive lesions were 64.3% for coiling, 54.5% for remodeling, 61.1% for stent-assisted coiling, 53.7% for flow-diverting stents, and 75% for very complex treatments (p = 0.4962). The 6-month procedure-related morbidity and mortality rates were 6.25% and 0%, respectively. At 6 months’ follow-up, 93% of the patients had modified Rankin Scale (mRS) scores of 0–2. Very complex treatments offered a higher complete occlusion rate (100%) than all other techniques (66.7%–88.9%). Age and length of procedure were independent factors for DWI lesion occurrence. The diameter of DWI lesions on 24-hour postprocedure MRI was positively correlated with mRS score at discharge. Among the DWI-positive lesions measuring less than 2 mm in diameter on the 24-hour MRI, 44.12% had regressed at 6 months.

CONCLUSIONS

Procedure-related DWI lesions are far more often encountered in silent forms than they are clinically evident. They do not seem to be significantly correlated with procedure-related complications, nor do they seem to impair clinical outcome, regardless of the endovascular technique. Small lesions (< 2 mm in diameter) may regress within 6 months. The use of the most adapted technique, in terms of aneurysm configuration, results in significant total occlusion rates, with acceptable safety.

A Comparison of Diffusion-Weighted Imaging Abnormalities Following Balloon Remodeling for Aneurysm Coil Embolization in the Ruptured vs Unruptured Setting

BACKGROUND

The prothrombotic milieu seen in subarachnoid hemorrhage (SAH) poses a unique challenge to neurovascular surgeons with regard to device use and microcatheter practice.

OBJECTIVE

To determine how demographic factors and balloon practices impact diffusion-weighted imaging (DWI) abnormalities and outcomes in patients with SAH compared to those without (non-SAH).

METHODS

We retrospectively analyzed 77 patients with SAH treated by balloon-assisted coiling in a single institution compared with 81 consecutive patients with unruptured aneurysms treated by balloon-assisted coiling at the same institution. Data were collected with regard to demographic factors, procedural and anatomic considerations, and DWI abnormalities on postprocedural magnetic resonance imaging.

RESULTS

SAH patients were significantly more likely to have DWI abnormality (75% vs 21%, P < .0001) and had a higher number and volume of DWI (4.0 vs 3.0, P = .0421 and 1.3 vs 0.3 cc, P = .0041) despite similar balloon practices. SAH patients were not more likely to have DWI abnormality in vascular territory distal to the treated aneurysm but had a higher likelihood of DWI in a vascular territory unrelated to the aneurysm (81.5% vs 47.1%, P = .0235). Patients without DWI abnormality were significantly more likely to have a good outcome as defined by modified Rankin Score 0 to 2 (95.6% vs 81.6%, P = .0328). Patients with DWI abnormality more often underwent 4-vessel angiography (70.5% vs 48.0%, P = .0174), but this was not found to be significant on multivariate analysis.

CONCLUSION

Balloon-assisted coiling does not result in increased incidence of downstream ischemic events in SAH patients compared to non-SAH patients and is safe in this cohort of patients. Other factors, such as 4-vessel angiography of the SAH milieu itself, may predispose patients to a higher rate of ischemic events.

Complications of endovascular treatment for intracranial aneurysms: Management and prevention

Endovascular coiling for intracranial aneurysms has become an accepted treatment with good clinical results and provides adequate protection against rebleeding and rupture of aneurysms. However, despite the experience, preparation, or skill of the physician, complications during endovascular treatment still occur. The main complications of endovascular coiling are: procedural aneurysmal perforations by the microcatheter, micro-guidewire, or coil, and thromboembolic events. Such situations are unexpected, complex, and can have devastating consequences. In this article, we present a comprehensive review of the two most common complications, aneurysmal perforation and thromboembolism during endovascular coiling, and how we can prevent or overcome these complications to achieve a satisfactory outcome. In addition, as the flow diverter has been become an important tool for management of large, wide necked, and other anatomically challenging aneurysms, we also describe complications stemming from the use of the tool, which remains a novel treatment option for complex aneurysms.

Comparison of endovascular and microsurgical management of 208 basilar apex aneurysms

OBJECTIVE

The deep and difficult-to-reach location of basilar apex aneurysms, along with their location near critical adjacent perforating arteries, has rendered the perception that microsurgical treatment of these aneurysms is risky. As a result, these aneurysms are considered more suitable for treatment by endovascular intervention. The authors attempt to compare the immediate and long-term outcomes of microsurgery versus endovascular therapy for this aneurysm subtype.

METHODS

A prospectively maintained database of 208 consecutive patients treated for basilar apex aneurysms between 2000 and 2012 was reviewed. In this group, 161 patients underwent endovascular treatment and 47 were managed microsurgically. The corresponding records were analyzed for presenting characteristics, postoperative complications, discharge status, and Glasgow Outcome Scale (GOS) scores up to 1 year after treatment and compared using chi-square and Student t-tests.

RESULTS

Among these 208 aneurysms, 116 (56%) were ruptured, including 92 (57%) and 24 (51%) of the endovascularly and microsurgically managed aneurysms, respectively. The average Hunt and Hess grade was 2.4 (2.4 in the endovascular group and 2.2 in the microsurgical group; p = 0.472). Postoperative complications of cranial nerve deficits and hemiparesis were more common in patients treated microsurgically than endovascularly (55.3% vs 16.2%, p < 0.05; and 27.7% vs 10.6%, p < 0.05, respectively). However, aneurysm remnants and need for retreatment were more common in the endovascular than the microsurgical group (41.3% vs 2.3%, p < 0.05; and 10.6% vs 0.0%, p < 0.05, respectively). Stent placement significantly reduced the need for retreatment. Rehemorrhage rates and average GOS score at discharge and 1 year after treatment were not statistically different between the two treatment groups.

CONCLUSIONS

Patients with basilar apex aneurysms were significantly more likely to be treated via endovascular management, but compared with those treated microsurgically, they had higher rates of recurrence and need for retreatment. The current study did not detect an overall difference in outcomes at discharge and 1 year after either treatment modality. Therefore, in a select group of patients, microsurgical treatment continues to play an important role.