Thromboembolic event detected by diffusion weighted magnetic resonance imaging after coil embolization of cerebral aneurysms

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.

Silent Embolic Infarction after Neuroform Atlas Stent-Assisted Coiling of Unruptured Intracranial Aneurysms

OBJECTIVE

There is still controversy regarding whether neck remodeling stent affects the occurrence of silent embolic infarction (SEI) after aneurysm coiling. Thus, the aim of the present study is to investigate the incidence of SEI after stent-assisted coiling (SAC) using Neuroform Atlas Stent (NAS) and possible risk factors. This study also includes a comparison with simple coiling group during the same period to estimate the impact of NAS on the occurrence of SEI.

METHODS

This study included a total of 96 unruptured intracranial aneurysms in 96 patients treated with SAC using NAS. Correlations of demographic data, aneurysm characteristics, and angiographic parameters with properties of SEI were analyzed. The incidence and characteristics of SEI were investigated in 28 patients who underwent simple coiling during the same period, and the results were compared with the SAC group.

RESULTS

In the diffusion-weighted imaging obtained on the 1st day after SAC, a total of 106 SEI lesions were observed in 48 (50%) of 96 patients. Of these 48 patients, 38 (79.2%) had 1-3 lesions. Of 106 lesions, 74 (69.8%) had a diameter less than 3 mm. SEI occurred more frequently in older patients (≥60 years, p=0.013). The volume of SEI was found to be significantly increased in older age (≥60 years, p=0.032), hypertension (p=0.036), and aneurysm size ≥5 mm (p=0.047). The incidence and mean volume of SEI in the SAC group (n=96) were similar to those of the simple coiling group (n=28) during the same period.

CONCLUSION

SEIs are common after NAS-assisted coiling. Their incidence in SAC was comparable to that in simple coiling. They occurred more frequently at an older age. Therefore, the use of NAS in the treatment of unruptured intracranial aneurysm does not seem to be associated with an increased risk of thromboembolic events if antiplatelet premedication has been performed well.

Thromboembolic complications during and after embolization of unruptured aneurysms: A chronological outcome in periprocedural thromboembolic events

Background

Ischemic complications develop after elective coil embolization procedures at a certain rate. The prevention of these events has been a longstanding issue for many interventional neuroradiologists. This study aimed to clarify whether procedural ischemic events after unruptured aneurysm embolization decrease over time with perioperative anti-thromboembolic treatment or surgical experience.

Methods

This study included patients with cerebral aneurysms in our institution between July 2012 and June 2020. Dual-antiplatelet therapy (DAPT) was performed (Phase 1). Thromboembolic events developed at a certain rate; thus, rivaroxaban was administered with single-antiplatelet therapy (SAPT) to improve thromboembolic results (Phase 2), showing better outcomes than in Phase 1. Subsequently, DAPT was administered again (Phase 3). Ischemic complications were evaluated in each phase or compared between the DAPT group and the direct oral anticoagulant (DOAC) with the clopidogrel (DOAC+SAPT) group.

Results

Relatively, fewer symptomatic ischemic events were noted in Phase 2 or the DOAC+SAPT group, but the outcome was not better in Phase 3 than in Phase 2. Symptomatic complications were more common in Phase 3 than in Phases 1 and 2.

Conclusion

Ischemic complications occurred at a certain rate after endovascular procedures for unruptured aneurysms. The incidence did not decrease over time; particularly, standard DAPT plus postoperative anti-thromboembolic medication did not adequately decrease complications in Phase 3 compared to Phases 1 and 2. Therefore, accumulated experience or a learning curve could not explain the results. DOAC administration might decrease the risk of these events, but further accumulation of evidence or prospective investigation is warranted.

Diffusion-weighted imaging lesions after endovascular treatment of cerebral aneurysms: A network meta-analysis

Background

Thromboembolism is one of the common complications in endovascular treatments including coiling alone, stent-assisted coiling (SAC), balloon-assisted coiling (BAC), and flow-diverting (FD) stents. Such treatments are widely used in intracranial aneurysms (IAs), which usually present as positive lesions in diffusion-weighted imaging (DWI). Whether these adjunctive techniques increase postprocedural DWI-positive lesions after endovascular treatment remains unclear.

Methods

A thorough electronic search for the literature published in English between January 2000 and October 2022 was conducted on PubMed, Medline, and EMBASE. Eighteen studies (3 cohort studies and 15 case-control studies) involving 1,843 patients with unruptured IAs (UIAs) were included. We performed a frequentist framework network meta-analysis (NMA) to compare the rank risks of cerebral thromboembolism of the above four endovascular treatments. The incoherence test was used to analyze the statistical disagreement between direct and indirect evidence. Funnel plots were used to analyze publication bias.

Results

The incidences of DWI lesions in patients who received FD stents, SAC, BAC, and coiling alone were 66.1% (109/165), 37.6% (299/795), 31.1% (236/759), and 25.6% (236/921). The incidence of DWI lesions in patients who received FD stents was higher than that in patients who received SAC [OR: 2.40; 95% CI (1.15, 5.00), P < 0.05], BAC [OR: 2.62; 95% CI (1.19, 5.77), P < 0.05], or coiling alone [OR: 2.77; 95% CI (1.26, 6.07), P < 0.05]. The incoherence test showed preferable consistency in this NMA. No obvious publication bias was found in the funnel plot.

Conclusion

FD stent placement brings more ischemic lesions identified by DWI than any other procedures for patients with UIA. The characteristics of FD stents may result in a high incidence of DWI lesions.

Enterprise stents versus low-profile visualized intraluminal support stents for stent-assisted coiling of unruptured paraclinoid aneurysms

BACKGROUND

The microsurgical treatment of paraclinoid aneurysms can be challenging due to the anatomical structures that surround them.

OBJECTIVE

This study compared the clinical and angiographic outcomes of unruptured paraclinoid aneurysms treated with enterprise (EP) stents and low-profile visualized intraluminal support (LVIS) stents.

METHODS

A retrospective analysis of the clinical and radiological data from 133 patients with 139 unruptured paraclinoid aneurysms, who received an EP or an LVIS stent between January 2017 and June 2021 at Taizhou People's Hospital, was performed. Immediate postoperative and follow-up angiographic results were analyzed retrospectively using the Raymond-Roy occlusion classification (RROC). Any complications following the procedure and the patients' clinical outcomes were noted.

RESULTS

Enterprise stents were used for stent-assisted coiling in 64 patients with 68 aneurysms and LVIS stents were used in 69 patients with 71 aneurysms. Both groups exhibited an increase in the proportion of aneurysms meeting the criteria for RROC class I, but the LVIS group demonstrated a higher rate of aneurysms meeting the class I criteria compared with the EP group, both on immediate postoperative angiography (45.1% vs. 11.8%, p< 0.001) and on follow-up angiography (94.9% vs. 80.6%, p= 0.025). Procedure-related complications were experienced by 9.4% of patients in the EP group (one coil prolapse, two parent artery occlusions, and three thromboembolic events), and 8.7% of patients in the LVIS group (three stent-related thrombosis and three thromboembolic events). There were no statistically significant differences between the two groups in relation to perioperative complications (p= 0.746) or favorable clinical outcomes (p= 0.492).

CONCLUSION

A greater proportion of aneurysms in the LVIS group met the criteria for RROC class I compared with the EP group. There is no significant difference in procedural complications or clinical outcomes between EP and LVIS stents. Although no aneurysm recurrence was observed during the short follow-up period, continued monitoring is required.

Thromboembolic Events Detected by Diffusion-Weighted Magnetic Resonance Imaging after Flow Diverter Treatment: The Impact of Procedure Time

BACKGROUND

Periprocedural thromboembolism is a serious complication of endovascular treatment for intracranial aneurysms. In addition to symptomatic ischemia, asymptomatic postprocedural diffusion-weighted image-positive lesions (DPLs) are considered important. However, few studies have reported significant risk factors associated with DPLs and symptomatic ischemic stroke after flow diverter (FD) treatment. This study aimed to investigate the frequency and risk factors associated with DPLs after FD treatment.

METHODS

Between November 2015 and December 2021, 84 patients harboring 85 untreated, unruptured intracranial aneurysms treated with FD were enrolled.

RESULTS

DPLs after FD treatment were confirmed in 74 patients (87.1%), among whom 69 (93.2%) were clinically asymptomatic. In the univariate analyses, age >55 years (P = 0.040), smoking (P = 0.023), preprocedural P2Y12 reaction unit value of >185 (P = 0.030), larger dome size of >9.3 mm (P = 0.013), and prolonged procedure time >80 minutes (P < 0.001) were significantly associated with postprocedural DPLs. In the multiple logistic regression model, only prolonged procedure time >80 minutes (odds ratio, 10.72; 95% confidence interval, 1.346-233.899; P = 0.023) was statistically significant. The mediator effect showed that the association between procedure time and the occurrence of DPLs was not significantly modified by any other factors, although only adjunctive coiling showed a tendency (P-value for interaction = 0.070).

CONCLUSIONS

Prolonged procedure time >80 minutes was the only identifiable factor related to postprocedural DPLs. Adjunctive coiling tended to mediate the effects of a prolonged procedure time on the occurrence of DPLs after FD treatment.

Thromboembolism during coiling of intracranial aneurysms: predictors and clinical outcome

Introduction

Thromboembolism is one of the most serious complications associated with coil embolization therapy.

Aim

To identify predisposing factors for thromboembolic complications, as well as to determine whether thromboembolism has an impact on clinical outcome.

Material and methods

From February 2008 to March 2015, 273 consecutive patients were treated at our institution via endovascular coil embolization. Patient medical records were reviewed with an emphasis on procedure description, potential risk factors and clinical outcomes related to thromboembolism. Thromboembolic incidents occurred in 19 (6.9%) cases. Multivariate logistic regression models were used to determine independent predictors of thromboembolism. Clinical outcome was analyzed using the Glasgow Outcome Scale (GOS).

Results

Multivariate analysis showed that subarachnoid hemorrhage was an independent risk factor for thromboembolic complications (p = 0.003; OR = 4.4; 95% CI: 1.67–12.02). The difference in frequency of perioperative mortality (GOS 1) in patients with thromboembolism and without thromboembolism was not statistically significant (p = 0.22). The differences in frequencies of severe disability (GOS 2–3) and moderate to low disability (GOS 4–5) between patients with thromboembolism and without thromboembolism were statistically significant in the general study population (p < 0.05).

Conclusions

Subarachnoid hemorrhage is an independent predictor of thromboembolic complications associated with endovascular coiling of cerebral aneurysms. Thromboembolism is associated with significantly increased risk of morbidity, and it affects to a certain extent the periprocedural mortality.

Clipping versus coiling in unruptured anterior cerebral circulation aneurysms

Background:

Unruptured intracranial aneurysms (UIAs) are not uncommon, especially in Japan. Treatment strategy for UIAs has evolved in the past decades in Western countries with the increased use of endovascular treatment as the primary option, but in Japan, clipping still has the upper hand.

Methods:

This study retrospectively included 200 patients treated by clipping or coiling for UIAs located in the anterior cerebral circulation. Postoperative angiographic and clinical outcomes were evaluated.

Results:

Of 200 UIAs, 147 and 53 were treated by surgery and coiling, respectively. The average follow-up duration was 30.2 ± 18.8 months for clipping and 29.3 ± 17.6 months for coiling. Complete occlusion was greater in the surgery group (78.9%) than the endovascular group (18.8%). Regrowth occurred in 1.4% of the clipping group and 13.2% of the coiling group. Ischemic events were encountered in both groups; asymptomatic ones were higher in the coiling group (24.5%) than in the clipping group (2%), while symptomatic ischemic complications were equal (7.5%) in both groups. The deterioration of modified Rankin scale was detected totally in 13 UIAs (6.5%) with no statistical difference between groups. Postoperative hospital period was longer in clipping (P = 0.01).

Conclusion:

Clipping and coiling were both safe and feasible in the treatment of unruptured aneurysms. The clipping was advantageous in durability, while the rate of morbidity was lower, and hospitalization period was shorter in the coiling group. The clipping and coiling should coexist while complementing each other by understanding the advantages and disadvantages of both.

Antiplatelet therapy for prevention of thromboembolic complications in coiling-only procedures for unruptured brain aneurysms

BACKGROUND AND PURPOSE

Thromboembolic events are recognized complications of aneurysm coiling.

OBJECTIVE

To identify any protective effects of antiplatelet therapy use before coiling of unruptured aneurysms.

METHODS

We conducted a meta-analysis of clinical studies published up to February 2019. We included studies reporting symptomatic thromboembolic events (defined as clinical stroke or transient ischemic attacks) in patients who received antiplatelet therapy before coiling of unruptured aneurysms using unassisted coiling, balloon assistance, or multiple microcatheters. We excluded ruptured aneurysms and those treated with stent coiling or flow diverters.

RESULTS

We identified 14 studies (2486 patients). All were single-center studies and four were prospective. In three studies with a control (no treatment) arm, the pooled risk ratio for symptomatic thromboembolic events with versus without antiplatelet therapy was 0.33 (95% CI 0.17 to 0.92, p= 0.035). The cumulative risk of symptomatic thromboembolic events with single antiplatelet agents was 5.0% '56/1122' (95% CI 1.6% to 8.4%, I²83.63%), and with dual or multiple agents 2.7% '33/1237' (95% CI 1.0% to 3.0%, I²39.9%). The incidence of diffusion lesions was reported in seven studies. It was 50.5% '96/190' (95% CI 7.3% to 93.9%, I²94.4%) with single agents compared with 43.9% '196/446' (95% CI 25.9% to 61.9%, I²73.4%) with dual or multiple agents.

CONCLUSION

Periprocedural antiplatelet therapy was associated with a low symptomatic thromboembolic event after coiling-only for unruptured aneurysms. However, available evidence is of limited quality with significant heterogeneity, requiring evidence from randomized controlled trials.

Tiny Cerebral Aneurysms Can Be Treated Safely and Effectively with Low-Profile Visualized Intraluminal Support Stent-Assisted Coiling or Coiling Alone

BACKGROUND

The effectiveness and safety of LVIS stent-coiling is currently not known for treating tiny intracranial aneurysms.

OBJECTIVE

To investigate the effectiveness and safety of Low-profile visualized intraluminal support (LVIS) stent-assisted coiling and coiling alone in treating patients with mostly ruptured tiny aneurysms.

METHODS

Seventy-five patients with tiny intracranial aneurysms, including 63 ruptured ones, were treated endovascularly and analyzed.

RESULTS

In the coiling group, complete occlusion was achieved in 35 patients (83.6%)-nearly complete in 4 patients (9.5%) and noncomplete in 3 patients (7.1%). Intraprocedural rerupture occurred in 2 patients (4.8%), and coil protrusion occurred in 1 patient, with a complication rate of 7.1%. Clinical follow-up at 6-12 months revealed a modified Rankin Scale (mRS) score of 0-1 in 41 patients and 3 in 1 patient. In the stent-assisted group, occlusion was complete in 12 patients (36.4%), nearly complete in 15 patients (45.5%), and noncomplete in 6 patients (18.1%). Six stents (18.2%) did not have good adherence to the wall, with thrombus formation in 3 stents (9.1%). Follow-up angiography in 27 patients at 3-6 months showed no dislocation of the stents, complete occlusion in 24 patients (88.9%), and nearly complete occlusion in the other 3 patients. At 6 months, the mRS score was 0 in 30 patients and 2 in 3 patients. No significant (P > 0.05) differences existed between the 2 groups.

CONCLUSION

Tiny cerebral aneurysms can be safely and effectively treated with appropriate endovascular approaches based on aneurysm specific morphology, especially neck size and neck-to-dome ratio.

Cerebral embolization, silent cerebral infarction and neurocognitive decline after thoracic endovascular aortic repair

Background

Silent cerebral infarction is brain injury detected incidentally on imaging; it can be associated with cognitive decline and future stroke. This study investigated cerebral embolization, silent cerebral infarction and neurocognitive decline following thoracic endovascular aortic repair (TEVAR).

Methods

Patients undergoing elective or emergency TEVAR at Imperial College Healthcare NHS Trust and Guy's and St Thomas' NHS Foundation Trust between January 2012 and April 2015 were recruited. Aortic atheroma graded from 1 (normal) to 5 (mobile atheroma) was evaluated by preoperative CT. Patients underwent intraoperative transcranial Doppler imaging (TCD), preoperative and postoperative cerebral MRI, and neurocognitive assessment.

Results

Fifty-two patients underwent TEVAR. Higher rates of TCD-detected embolization were observed with greater aortic atheroma (median 207 for grade 4–5 versus 100 for grade 1–3; P = 0·042), more proximal landing zones (median 450 for zone 0–1 versus 72 for zone 3–4; P = 0·001), and during stent-graft deployment and contrast injection (P = 0·001). In univariable analysis, left subclavian artery bypass (β coefficient 0·423, s.e. 132·62, P = 0·005), proximal landing zone 0–1 (β coefficient 0·504, s.e. 170·57, P = 0·001) and arch hybrid procedure (β coefficient 0·514, s.e. 182·96, P &lt; 0·001) were predictors of cerebral emboli. Cerebral infarction was detected in 25 of 31 patients (81 per cent) who underwent MRI: 21 (68 per cent) silent and four (13 per cent) clinical strokes. Neurocognitive decline was seen in six of seven domains assessed in 15 patients with silent cerebral infarction, with age a significant predictor of decline.

Conclusion

This study demonstrates a high rate of cerebral embolization and neurocognitive decline affecting patients following TEVAR. Brain injury after TEVAR is more common than previously recognized, with cerebral infarction in more than 80 per cent of patients.

Antiplatelet therapy for the prevention of peri-coiling thromboembolism in high-risk patients with ruptured intracranial aneurysms

OBJECTIVE

The most frequent procedural complication of the endovascular treatment of intracranial aneurysms is a thromboembolic event (TEE); in a subset of patients, such events will cause permanent neurological disability. In patients with unruptured aneurysms, increasing evidence supports the use of periprocedural antiplatelet therapy to prevent TEEs. The object of this study was to evaluate whether patients with ruptured aneurysms and subarachnoid hemorrhage would also benefit from periprocedural antiplatelet therapy.

METHODS

The authors reviewed a prospective registry of 169 patients with endovascularly treated intracranial aneurysms to delineate angiographic features associated with periprocedural TEEs. They then performed a controlled before-and-after study in 79 patients with ruptured aneurysms who were deemed to be at high risk for TEEs (for example, patients with at least 1 angiographic feature associated with TEEs) to evaluate whether selective aspirin administration would reduce the rate of periprocedural thromboembolism without increasing major hemorrhagic complications.

RESULTS

Six angiographic features were associated with periprocedural TEEs in the study cohort: wide aneurysm neck, coil or loop protrusion, small parent artery diameter, an incorporated branch, intraprocedural thrombus formation, and intracranial parent vessel atherosclerosis. Aspirin administration to high-risk patients significantly decreased the rate of periprocedural TEEs, from 53.8% in the control group to 10.6% in the aspirin-treated group (p = 0.001). The reduction in TEEs in the aspirin-treated group continued to be statistically significant even when adjusted for age, sex, cardiovascular risk factors (smoking, diabetes, hypertension, dyslipidemia, coronary artery disease), and factors associated with TEEs in other large studies (wide aneurysm neck, aneurysm size ≥ 10 mm), with an adjusted OR of 0.16 (95% CI 0.03–0.8). There were no major systemic hemorrhagic complications, and aspirin did not increase the risk of aneurysm rebleeding, symptomatic intracranial hemorrhage, or major external ventricular drain (EVD)–associated hemorrhage (p = 0.3), though there was an increase in asymptomatic, minor (< 1 cm) EVD-associated hemorrhage in the aspirin-treated group (p = 0.02).

CONCLUSIONS

The study findings suggest that for ruptured aneurysm patients with high-risk features, antiplatelet therapy can significantly reduce the rate of periprocedural TEE without increasing major systemic or intracranial hemorrhages.

Preliminary Experience with Stent-Assisted Coiling of Aneurysms Arising from Small (<2.5 mm) Cerebral Vessels Using The Low-Profile Visualized Intraluminal Support Device

BACKGROUND AND PURPOSE

The Low-Profile Visualized Intraluminal Support (LVIS) stent is a new device recently introduced for the treatment of wide-neck intracranial aneurysms. This single-center study presents the authors' preliminary experience using the LVIS stent to treat saccular aneurysms with parent arteries smaller than 2.5 mm.

MATERIALS AND METHODS

Aneurysms with a LVIS stent used in a small parent vessel (<2.5 mm in diameter) between October 2014 and April 2016 were included. Procedure-related complications, angiographic results, clinical outcomes, and midterm follow-up data were analyzed retrospectively.

RESULTS

A total of 22 patients was studied, including 5 ruptured and 17 unruptured aneurysms. Most of the aneurysms were located in the anterior circulation (90.9%). Stent placement in the parent arteries measuring 1.7-2.4 mm in diameter (mean, 2.1 mm) was successful in 100% of cases. Procedure-related complication developed in 1 patient (4.5%) who presented with aneurysm rupture. No permanent morbidity and mortality occurred. Immediate angiographic outcome showed complete occlusion in 8 aneurysms (36.4%), neck residual in 8 (36.4%), and residual aneurysm in 6 (27.3%). All patients underwent angiographic follow-up at a mean of 8.3 months, which revealed complete occlusion in 18 (81.8%) patients, neck remnant in 3 (13.6%), and residual sac in 1 (4.5%). No recanalization of the target aneurysm was observed. There was 1 case with asymptomatic in-stent stenosis.

CONCLUSIONS

Our preliminary results show that the deployment of LVIS stents in small vessels is feasible, safe, and effective in the midterm. Larger studies with long-term follow-up are needed to validate our promising results.

Stent-Assisted Endovascular Treatment of Anterior Communicating Artery Aneurysms - Literature Review

The anterior cerebral artery is a common location of intracranial aneurysms. The standard coil embolization technique is limited by its inability to occlude wide-neck aneurysms. Stent deployment across the aneurysm neck supports the coil mass inside the aneurysmal sac, and furthermore, has an effect on local hemodynamic and biologic changes. In this article, various management strategies and techniques as well as angiographic outcomes and complications related to stent-assisted endovascular treatment of anterior communicating artery aneurysms are presented. This treatment method is safe and associated with low morbidity and mortality rates.

The safety and efficacy of low profile visualized intraluminal support (LVIS) stents in assisting coil embolization of intracranial saccular aneurysms: a single center experience

BACKGROUND

The low profile visualized intraluminal support (LVIS) device is a new generation of self-expanding braided stents recently introduced into China for stent assisted coiling of intracranial aneurysms. This study assessed the clinical safety and efficacy of the LVIS stent for embolization of intracranial saccular aneurysms.

METHODS

Patients with intracranial saccular aneurysms treated using the LVIS device in our center between April 2014 and December 2014 were reviewed. The primary outcomes were procedural safety, target aneurysm recurrence, and mid-term follow-up of clinical and angiographic outcomes.

RESULTS

97 patients with intracranial saccular aneurysms were treated using the LVIS stent, with 100% technical success rate. No mortality was observed. One patient had transient deficit (1/97, 1.0%). Immediate angiographic outcome evaluation showed complete occlusion in 28 (28.8%) and neck remnant in 39 (40.2%) of the 97 patients, respectively. Of the 76 (78.35%) patients who underwent angiographic follow-up at a mean of 8.1 months, complete occlusion was achieved in 64 (84.2%) patients. In the remaining patients, neck remnant in nine (11.8%) and residual sac in three (4%) patients were observed. None of the patients had any target aneurysm recurrence, and the mortality rate was 0%.

CONCLUSIONS

The LVIS stent is safe and effective in the treatment of intracranial saccular aneurysms.

Incidence of delayed ipsilateral intraparenchymal hemorrhage after stent-assisted coiling of intracranial aneurysms in a high-volume single center

INTRODUCTION

Delayed ipsilateral intraparenchymal hemorrhage (IPH) has been reported following technically successful treatment of intracranial aneurysms using flow-diverting stents in up to 8.5% of patients. We report a similar, though less frequent phenomenon in the setting of stent-assisted coil embolization.

METHODS

Institutional review board approval was obtained. A retrospective analysis of a prospective neurointerventional procedure registry was performed to review all IPHs that occurred in aneurysm patients within 90 days of endovascular treatment performed between November 2002 and November 2014 at one institution. Age, sex, hypertension, dual antiplatelet therapy, and technical details of the procedure were recorded.

RESULTS

A total of 1697 patients underwent endovascular treatment of an intracranial aneurysm without a flow diverter at our institution during the study period. Among these, 138 patients underwent stent-assisted coiling (8.1%). Of these, three patients (2.2%) suffered a delayed IPH within the vascular territory distal to the treated lesion (one woman, median age 60 years).

CONCLUSIONS

Recently described in the setting of flow diversion, delayed ipsilateral IPH is not limited to flow-diverting stents. Though less frequent, a potential for this complication may exist following any intracranial stenting procedure, possibly related to hemorrhagic conversion of microembolic phenomena in the setting of dual antiplatelet or anticoagulation therapy.