Triple antiplatelet therapy with addition of cilostazol to aspirin and clopidogrel for Y-stent-assisted coil embolization of cerebral aneurysms

DWI-Detected Ischemic Lesions after Endovascular Treatment for Cerebral Aneurysms: An Updated Systematic Review and Meta-analysis

BACKGROUND AND PURPOSE

DWI-detected ischemic lesions are potential complications of endovascular procedures that are performed to treat intracranial aneurysms. We completed a systematic review and meta-analysis to identify the occurrence of DWI-detected ischemic lesions after endovascular treatment for intracranial aneurysms.

MATERIALS AND METHODS

A systematic literature search of PubMed, the Web of Science, EMBASE, and Scopus between January 2000 and June 2022 of post-endovascular procedures for intracranial aneurysm studies was conducted using the Nested Knowledge AutoLit software. The main outcome was DWI-detected ischemic lesions within 5 days of the procedures. Information regarding associated risk factors such as the type of procedure, patient demographics, and aneurysm characteristics was also collected.

RESULTS

Twenty-nine studies with 2686 patients were included. The overall incidence of DWI ischemic lesions was 47.0% (95% CI, 39.6%-55.8%). The highest rate of lesions was seen with flow diversion at 62.4% (95% CI, 48.4%-80.5%), followed by complex procedures at 49.3% (95% CI, 29.5%-82.1%), stent-assisted coiling at 47.5% (95% CI, 34.6%-65.3%), simple coiling at 47.1% (95% CI, 35.7%-62.3%), and balloon-assisted coiling at 37.0% (95% CI, 28.3%-48.4%). The differences among different techniques were not statistically significant; however, there was significant heterogeneity and a significant risk of publication bias among included studies.

CONCLUSIONS

Many patients who undergo endovascular procedures for intracranial aneurysms present with new postprocedural DWI-detected ischemic lesions, regardless of the endovascular procedure used. Future studies and meta-analyses are needed to investigate early and long-term outcomes of such small infarcts.

Ticagrelor versus clopidogrel in stent-assisted coil embolization of unruptured intracranial aneurysms

BACKGROUND

Dual antiplatelet therapy is widely used for stent-assisted coil embolization (SACE) for unruptured intracranial aneurysms (UIAs) to prevent thromboembolic events (TEs). Compared to clopidogrel associated with aspirin, knowledge of the safety and efficacy of ticagrelor is lacking in large studies to date.

METHODS

A retrospective cohort study was conducted from January 2016 to December 2018 with at least one year of follow-up in a single institution and systemic review.

RESULTS

Altogether, 153 patients with UIA receiving SACE were separated into two groups: 113 patients receiving clopidogrel plus aspirin and 40 patients receiving ticagrelor plus aspirin. Acute in-stent thrombotic events were noted in two patients in the clopidogrel group (1.77%) and none in the ticagrelor group (0%). Additionally, one patient (0.88%) in the clopidogrel group had an early ischemic stroke (<3 months). Delayed ischemic stroke was noted in 6 patients (5.31%) in the clopidogrel group and 3 patients (7.50%) in the ticagrelor group. There were no major hemorrhagic events in either group. The two groups showed no significant differences with regard to ischemic stroke or hemorrhagic stroke.

CONCLUSION

Compared to the clopidogrel based regimen, ticagrelor can also reduce TEs without increasing bleeding tendency for SACE of UIAs. Ticagrelor combined with low-dose aspirin is a safe and effective alternative option for SACE.

Levels of anti-oxidative molecules and inflammatory factors in patients with vascular dementia and their clinical significance

Objectives:

To explore levels of anti-oxidative molecules and inflammatory factors in patients with vascular dementia (VD) and their clinical significance.

Methods:

Sixty VD patients admitted in our hospital from January 2016 to January 2019 were classified into an experimental group, while another 60 healthy patients seeking physical examinations in the corresponding period were selected as a control group. Various indexes related to serum inflammatory factors and anti-oxidative molecules were compared among patients in such two groups. For the purpose of comparing anti-oxidative molecular expression levels and inflammatory factor levels in patients with VD of different severities, 60 cases in the experimental group were divided, based on a Mini-mental State Examination (MMSE) scale, into patients with mild symptoms (n=20, score: 21~26), patients with moderate symptoms (n=22, score: 10~20) and patients with severe symptoms (n=18, score: 0~9).

Results:

By contrast to the control group, levels of inflammatory factors (e.g., TNF-a, CRP and IL-6) in VD patients are all significantly increased and their differences show statistical significance (p<0.05); and, expression levels of anti-oxidative factors, including superoxide dismutase (SOD), glutathion peroxidase (GSH-Px), total antioxidant capacity (TAC), catalase (CAT) and glutathione reductase (GR), in the experimental group are apparently below those of the control group (P<0.05). As dementia degree increases, expression levels of serum anti-oxidative molecules in such patients are inclined to drop in a significant way (P<0.05), while inflammatory factor levels tend to go up gradually (P<0.05).

Conclusions:

If compared with the normal population, inflammatory factor levels in serum of VD patients are higher; however, expression levels of anti-oxidative molecules become below those of the normal population. Additionally, levels of inflammatory factors and anti-oxidative molecules may change obviously as severity of illness increases. This suggests that inflammation and oxidation play a certain role of auxoaction in VD patients.

Novel Noncrossing Y-Stent Technique Using Tapered Proximal End of a Solitaire AB Stent for Coil Embolization of Wide-Neck Bifurcation Aneurysms

The crossing Y-stent method is one of the indispensable techniques to achieve sufficient neck coverage during coil embolization of bifurcation aneurysms with a wide neck and/or branch incorporation. However, the inevitable hourglass-like expansion of the second stent at the crossing point can result in insufficient vessel wall apposition, reduced aneurysm neck coverage, delayed endothelialization, and subsequent higher risks of acute or delayed thrombosis. It also interferes with engagement of the microcatheter into the aneurysm after stent installation. We expected to be able to reduce these disadvantages by installing a noncrossing type Y-stent using the Solitaire AB stent, which is fully retrievable with a tapered proximal end. Here we report the techniques and two successful cases.

Y-configuration stenting for coiling of wide-neck bifurcation aneurysms using Low-profile Visualized Intraluminal Support Junior

Background

Little has been reported about the feasibility and durability of a Low-profile Visualized Intraluminal Support Junior (LVIS Jr) Y-stenting device for wide-neck bifurcation aneurysms.

Purpose

To evaluate the feasibility and durability of LVIS Jr Y-stenting for coiling of unruptured wide-neck bifurcation aneurysms.

Methods

We identified patients in whom LVIS Jr Y-stenting was attempted for unruptured wide-neck bifurcation aneurysms from a prospectively maintained registry of a referral hospital. Procedural success rate, treatment-related morbidity, and clinical and angiographic outcomes were retrospectively assessed.

Results

LVIS Jr Y-stenting was attempted for a total of 21 aneurysms in 21 patients (mean age 60±8.9 years; M:F=6:15): nine basilar artery, six anterior communicating artery, four middle cerebral artery, one internal carotid artery, and one vertebrobasilar fenestration aneurysms. The mean dome and neck size were 7.9±2.7 mm and 5.7±1.8 mm, respectively. All attempts were successful. Treatment-related morbidity occurred in one individual with a modified Rankin Scale (mRS) score of 2. Immediate postprocedural angiograms showed complete occlusion in 15 (71.4%) and neck remnant in 6 (28.6%) patients. All 21 patients had good outcomes (mRS score 0–2) for a mean of 12 months' follow-up (range 6–27 months); mRS score 0 in 20 patients and mRS score 2 in one patient, respectively. Follow-up imaging over a mean of 11 months (range 6–18 months) was available in 18 patients (85.7%). All aneurysms showed complete occlusion at follow-up.

Conclusions

LVIS Jr Y-stenting and coiling for wide-neck bifurcation aneurysms seems to be feasible with acceptable safety and to provide durable aneurysm occlusion for wide-neck bifurcation aneurysms.

Midterm results of T-stent–assisted coiling of wide-necked and complex intracranial bifurcation aneurysms using low-profile stents

OBJECTIVE

Coiling of wide-necked and complex bifurcation aneurysms frequently requires implantation of double stents in various configurations. T-stent–assisted coiling involves the nonoverlapping implantation of 2 stents to protect the daughter vessels of bifurcation and is followed by coiling of the aneurysm. The authors studied the feasibility, efficacy, and safety of the T-stent–assisted coiling procedure as well as the midterm angiographic/clinical outcomes of patients with wide-necked bifurcation intracranial aneurysms treated using this technique.

METHODS

The authors retrospectively identified patients with wide-necked bifurcation intracranial aneurysms treated using double-stent–assisted coiling with a T-stent configuration.

RESULTS

Twenty-four patients with 24 aneurysms and a mean of age of 51.91 years were identified. The most common locations were the middle cerebral bifurcation (45.8%) and anterior communicating artery (35.7%). T stentings were performed using low-profile stents. The procedures were performed with a technical success rate of 95.8%, and an immediate total occlusion rate of 79.2% was achieved. We observed periprocedural complications in 16.7% of cases and a delayed thromboembolic event in 4.2%. The complications caused permanent morbidity in 1 patient (4.2%). No deaths occurred. The mean angiographic follow-up duration was 9.3 months. The total occlusion rate at the last follow-up was 81.2%. The recanalization rate was 4.5%. Modified Rankin Scale scores of all patients at the last follow-ups were between zero and 2.

CONCLUSIONS

T-stent–assisted coiling using low-profile stents is a feasible, effective, and relatively safe endovascular technique used to treat wide-necked and complex intracranial aneurysms. The midterm angiographic and clinical outcomes are outstanding.

Contribution of the straightening effect of the parent artery to decreased recanalization in stent-assisted coiling of large aneurysms

OBJECTIVE The durability of embolization of large aneurysms is enhanced by use of the neck-bridging stent. However, it remains unclear what factors contribute to decreased recanalization. The purpose of this study was to demonstrate the contribution of the straightening effect of the parent artery to the durability of stent-assisted coiling for large aneurysms. METHODS Of the 182 aneurysms treated by embolization since the introduction of the neurovascular stent, 82 consecutive unruptured aneurysms with a diameter greater than 7 mm were selected. There were 52 aneurysms treated with a stent (Group S) and 30 treated without a stent (Group NS). Occlusion status was evaluated 12 months after embolization with digital subtraction angiography. The vascular angle of the parent artery was measured before, immediately after, and 12 months after embolization. The rates of recanalization were compared between Group S and Group NS. In Group S, the rates of recanalization were further compared between those aneurysms with and without a significant angle change. RESULTS The rate of major recanalization was 9.6% in Group S and 26.7% in Group NS. The volume embolization ratio was 32.6% in Group S and 31.6% in Group NS, with no statistically significant difference. However, the angulation change before and after coiling was significantly higher in Group S (10.6°) than in Group NS (0.9°). The difference in the angulation was more evident 12 months after coiling (19.1° in Group S and 1.5° in Group NS). In Group S, recanalization was found in 14.3% of 35 stented aneurysms without a significant angular change when a significant angular change was defined as more than 20°. In contrast, all 17 aneurysms with ≥ 20° of angular change remained occluded. CONCLUSIONS Significant angular change of ≥ 20° most likely leads to decreased recanalization following stent-assisted embolization of large aneurysms.

Endovascular treatment of complex intracranial aneurysms using Acandis Acclino stents

Objective

To determine the safety and effectiveness of a new low-profile, laser-cut, closed-cell stent system in the treatment of complex intracranial aneurysms.

Methods

A total number of 43 patients with complex intracranial aneurysms were treated using 60 Acandis Acclino stent systems (follow-up 2012–2016; mean 11 months). 36 patients presented with wide-necked intracranial aneurysms, dissecting aneurysms were seen in 7 patients. 39 patients received stent-assisted coiling. We analyzed demographic data and follow-up results.

Results

Sixty stents were successfully deployed. In one paraophthalmic internal carotid artery aneurysm the stent could not be placed. Thirty-three wide necked aneurysms were treated by single or multiple stent-assisted coiling. Complete occlusion was achieved in 31 of those cases (94% Raymond−Roy occlusion classification, RROC 1). Two patients showed stable residual aneurysmal filling (RROC 3). In three wide-necked aneurysms, sole stenting was the preferred treatment. For dual stent-assisted procedures the kissing-Y stenting technique was successfully performed in 11 aneurysms. In all dissecting aneurysms constructive therapy with stenting and preservation of the affected parent artery was achieved. Additional subsequent coil embolization was intentionally planned and successfully performed in 6 of the 7 dissecting aneurysms. The overall directly procedure-related complication rate was 7%, including one death.

Conclusions

Endovascular treatment of complex intracranial aneurysms using Acclino stents is a feasible and safe procedure with low complication rates. Even severe cases can be treated among others using the kissing-Y stenting technique, with good mid-term results.

In vitro experiments of vessel wall apposition between the Enterprise and Enterprise 2 stents for treatment of cerebral aneurysms

BACKGROUND

A closed-cell stent called Enterprise has been used for stent-assisted coil embolization of cerebral aneurysms. The Enterprise stent tends to cause kinks and vessel wall malposition in curved vessels and may cause thromboembolic complications. We evaluated vessel wall apposition of a new closed-cell stent, Enterprise 2, compared with a previous Enterprise stent, using curved vascular silicone models.

METHODS

The Enterprise or Enterprise 2 stent was deployed in curved vascular models with various radii of approximately 5 to 10 mm. Stent deployment was performed 25 times in each stent. A push-pull technique was used to minimize incomplete wall apposition. To evaluate conformity of stents, gaps between a stent and a vessel wall were measured.

RESULTS

The gap ratio (gap / a wall diameter) was 15 % ± 17 % (mean ± standard deviation) and 41 % ± 15 % with the Enterprise 2 stent and the Enterprise stent, respectively. Taking gap ratios and radii of vessel curvature into consideration, the Enterprise 2 stent had significantly better wall apposition than the Enterprise stent (p = 0.005). In the same radius of vessel curvature, the Enterprise 2 stent had approximately half of the gap compared with the Enterprise stent. There were no significant differences in vessel straightening effects between the two stents.

CONCLUSIONS

The Enterprise 2 stent has better wall apposition in curved vessels than the Enterprise stent. The gap between a vessel wall and the Enterprise 2 stent is approximately half that of the Enterprise stent. However, gaps and kinks are still present in curved vessels with a small radius. Caution should be taken for kinks and malposition in acutely curved vessels, such as the siphon of the internal carotid artery.

[Neurosurgery in a patient on dual antiplatelet therapy. Case report and the review of the literature]

INTRODUCTION

A neurosurgical intervention in a patient on dual antiplatelet therapy is a serious challenge for both the neurosurgeon and anesthesiologist..

MATERIAL AND METHODS

The article describes a clinical case of a successful urgent neurosurgical intervention (ventriculoperitoneostomy for obstructive hydrocephalus caused by a large meningioma of the posterior surface of the petrous pyramid) in a patient on dual antiplatelet therapy (DAT) due to a recently placed coronary stent..

CONCLUSION

Given a high risk of coronary stent thrombosis, the surgery was performed in the presence of ongoing DAT. There were no intracranial hemorrhagic complications, but subcutaneous hemorrhagic complications developed. The article discusses the features of managing similar patients whose number is growing.

Microembolism after endovascular coiling of unruptured cerebral aneurysms: incidence and risk factors

OBJECTIVE

The incidence and risk factors of microembolic lesions on MR diffusion-weighted imaging (DWI) were analyzed after the endovascular coiling of unruptured intracranial aneurysms (UIAs).

METHODS

Data obtained from 271 consecutive patients (70 men and 201 women; median age 57 years; range 23-79 years) who presented with UIA for coil embolization between July 2011 and June 2013 were analyzed. Two independent reviewers examined the DWI and apparent diffusion coefficient maps obtained the following day for the presence of restrictive diffusion spots and counted the number of spots. Multivariate analysis was then performed to identify independent risk factors for developing microembolism following the coiling of an aneurysm.

RESULTS

Microembolic lesions were noted in 101 of 271 patients (37.3%). The results of the multivariate analysis showed that the following factors significantly influenced the risk for microembolism: age, diabetes, previous history of ischemic stroke, high-signal FLAIR lesions in the white matter, multiple aneurysms, and the insertion of an Enterprise stent (all ORs > 1.0 and all p values < 0.05). Previously known risk factors such as prolonged procedure duration, aneurysm size, and decreased antiplatelet function did not show any significant influence.

CONCLUSIONS

The incidence of microembolism after endovascular coiling of UIA was not low. Lesions occurred more frequently in patients with vascular status associated with old age, diabetes, and previous stroke. Aneurysm multiplicity and the type of stent used for treatment also influenced lesion occurrence.

Microembolism after Endovascular Treatment of Unruptured Cerebral Aneurysms: Reduction of its Incidence by Microcatheter Lumen Aspiration

PURPOSE

Diffusion-weighted MR images (DWI) obtained after endovascular treatment of cerebral aneurysms frequently show multiple high-signal intensity (HSI) dots. The purpose of this study was to see whether we could reduce their incidence after embolization of unruptured cerebral aneurysms by modification of our coiling technique, which involves the deliberate aspiration of the microcatheter lumen right after delivery of each detachable coil into the aneurysm sac.

MATERIALS AND METHODS

From January 2011 to June 2011, all 71 patients with unruptured cerebral aneurysms were treated using various endovascular methods. During the earlier period, 37 patients were treated using our conventional embolization technique (conventional period). Then 34 patients were treated with a modified coiling technique (modified period). DWI was obtained on the following day. We compared the occurrence of any DWI HSI lesions and the presence of the symptomatic lesions during the two time periods.

RESULTS

The incidence of the DWI HSI lesions differed significantly at 89.2% (33/37) during the conventional period and 26.5% (9/34) during the modified period (p < 0.0001). The incidence of symptomatic lesions differed between the two periods (29.7% during the conventional period vs. 2.9% during the modified period, p < 0.003).

CONCLUSION

Aspiration of the inner content of the microcatheter right after detachable coil delivery was helpful for the reduction of the incidence of microembolisms after endovascular coil embolization for the treatment of unruptured cerebral aneurysms.

Hemodynamic effects of stent struts versus straightening of vessels in stent-assisted coil embolization for sidewall cerebral aneurysms

Background

Recent clinical studies have shown that recanalization rates are lower in stent-assisted coil embolization than in coiling alone in the treatment of cerebral aneurysms.

Objective

This study aimed to assess and compare the hemodynamic effect of stent struts and straightening of vessels by stent placement on reducing flow velocity in sidewall aneurysms, with the goal of reducing recanalization rates.

Methods

We evaluated 16 sidewall aneurysms treated with Enterprise stents. We performed computational fluid dynamics simulations using patient-specific geometries before and after treatment, with or without stent struts.

Results

Stent placement straightened vessels by a mean (±standard deviation) of 12.9°±13.1° 6 months after treatment. Placement of stent struts in the initial vessel geometries reduced flow velocity in aneurysms by 23.1%±6.3%. Straightening of vessels without stent struts reduced flow velocity by 9.6%±12.6%. Stent struts had significantly stronger effects on reducing flow velocity than straightening (P = 0.004, Wilcoxon test). Deviation of the effects was larger by straightening than by stent struts (P = 0.01, F-test). The combination of stent struts and straightening reduced flow velocity by 32.6%±12.2%. There was a trend that larger inflow angles produced a larger reduction in flow velocity by straightening of vessels (P = 0.16).

Conclusion

In sidewall aneurysms, stent struts have stronger effects (approximately 2 times) on reduction in flow velocity than straightening of vessels. Hemodynamic effects by straightening vary in each case and can be predicted by inflow angles of pre-operative vessel geometry. These results may be useful to design a treatment strategy for reducing recanalization rates.

Y-configuration double-stent-assisted coiling using two closed-cell stents for wide-neck basilar tip aneurysms

BACKGROUND

This study aimed to evaluate clinical and angiographic outcomes of Y-configuration double-stent-assisted (Y-stent) coiling using two closed-cell stents for wide-necked basilar tip aneurysm (BTA).

MATERIALS

A total of 25 patients underwent Y-stent coiling using two closed-cell stents as a first-time treatment in 18 (3 ruptured) BTAs, retreatment in 2 BTAs and as a third treatment in 5 wide-necked BTAs. Clinical and angiographic outcomes were evaluated retrospectively.

RESULTS

Treatment-related complications were three (12.0 %) thromboembolic infarctions due to two acute in-stent thromboses and one embolism. Twenty-two (88 %) patients had favorable outcomes (modified Rankin scale score [mRS], 0-2) during the follow-up period (mean, 30 months; range, 6-54 months). Two patients died: one from initial subarachnoid hemorrhage and the other from intracerebral hemorrhage due to underlying Moyamoya disease. Post-treatment angiograms showed complete occlusion in nine aneurysms, residual neck in 11 aneurysms and residual sac in five aneurysms. Follow-up angiograms were available at least once between 5 to 34 months (mean, 16 months) in 21 patients. Nineteen patients showed improved or stable states (complete occlusion, n = 17; residual neck, n = 2). Major recurrences occurred in two BTAs (9.5 %). Those two major recurrent aneurysms had been large-sized aneurysms at the initial coiling procedure. Both showed not only coil compaction but also progressive growth to giant-sized aneurysms and intra-aneurysmal thrombus formation at the Y-stent coiling as a third-time treatment.

CONCLUSIONS

Y-stent coiling using two closed-cell stents is a safe and durable treatment option for wide-necked BTA, but may have limited efficacy for large/giant sized and thrombosed aneurysms.

Feasibility of insertion of a microcatheter through a Y-stent in coil embolization of cerebral aneurysms and its detailed geometry by micro-computed tomography

BACKGROUND

In Y-stent-assisted coil embolization for cerebral aneurysms, open or closed cell stents are used. Different microcatheters for coil insertion are available. We investigated which microcatheter could be navigated into an aneurysm through a Y-stent with different stents.

METHODS

Double Neuroform open-cell stents or double Enterprise closed-cell stents were deployed in Y-configuration in a silicon model of a bifurcation aneurysm. Two endovascular neurosurgeons independently tried to navigate an SL-10 microcatheter for 0.010" coils or a PX Slim microcatheter for 0.020" Penumbra coils into the aneurysm through the Y-stent. In addition, we measured lengths of stent pores of the Y-stents with double Enterprise stents deployed in the model by micro-computed tomography.

RESULTS

It was feasible to navigate an SL-10 microcatheter into the aneurysm through the Y-stent with Enterprise or Neuroform stents. Navigation of a PX Slim microcatheter was feasible in the Y-stents only with Neuroform stents. In the Y-stent with double Enterprise stents, the lengths of the second stent pores were significantly smaller than those of the first stent (0.41 ± 0.18 mm vs 0.69 ± 0.20 mm; P = 0.008). The SL-10 microcatheter was smaller than approximately 80% of the stent pores of the first stent and 30% of those of the second stent. The PX Slim microcatheter was smaller than 20% of the stent pores of the first stent and 0% of those of the second stent.

CONCLUSIONS

It was feasible to insert an SL-10 microcatheter into the aneurysm through Y-stents with Enterprise or Neuroform stents. Navigation of a PX Slim microcatheter for 0.020" Penumbra coils was feasible in Y-stents with Neuroform stents, but not with double Enterprise stents. The measurements of stent pores by micro-computed tomography supported this feasibility study. These results may be helpful to select appropriate stents and microcatheters in Y-stent-assisted coil embolization, especially in case of retreatments.