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

Safety and efficacy of the Low-Profile Visualized Intraluminal Support stent in treating intracranial atherosclerotic stenosis

PURPOSE

The performance of the Low-Profile Visualized Intraluminal Support (LVIS) stent deployed following balloon angioplasty is unknown in treating intracranial atherosclerotic stenosis, and this study was to investigate the safety and efficacy of the LVIS stent in treating intracranial atherosclerotic stenosis in the middle cerebral artery M1 segment.

METHODS

Thirty-five patients were enrolled with 35 atherosclerotic stenoses at the M1 segment. The stenosis was about 75% in 16 patients, 80% in 15, and 90% in the rest four. The LVIS stent was used to treat these patients.

RESULTS

The success rate of stenting was 97.1%. The stenting procedure was failed in one patient because of intraprocedural dissection of the stenotic (75%) segment, resulting in a 30-day periprocedural complication rate of 2.9% (1/35). Before stenting, the stenosis rate ranged 75%-90% (mean 78.9%±4.7%), and after stenting, the diameter of the stented segment was significantly (P<0.0001) increased to 1.5-3.4mm (mean 2.1±0.32mm) ranging 68.2%-100% (mean 94.0%±5.8%) of the normal arterial diameter, with the residual stenosis ranging 0-31.8% (median 4.8%, IQR 2.4%-7.3%). Follow-up was performed at 6-20 months (mean 8.5) after stenting. One patient (2.9%) had occlusion of the stented M1 segment with no symptoms, and two patients (5.7%) had slight asymptomatic instent stenosis (40%) at the M1 segment, with the instent restenosis and occlusion rate of 8.6% (3/35).

CONCLUSION

The braided LVIS stent can be safely applied for treatment of intracranial atherosclerotic stenosis in the middle cerebral artery with good safety and efficacy immediately after stenting and at follow-up.

Initial and mid-term results of LEO Baby stent-assisted coiling of intracranial aneurysms located in small arteries: A single-center experience with 131 consecutive patients

Background and purpose

Low-profile intracranial stents such as the LEO Baby stents are considered to be advantageous for the treatment of intracranial aneurysms originating from small arteries. This study aimed to evaluate the initial and mid-term clinical and angiographic results of LEO Baby stents in stent-assisted coiling of intracranial aneurysms with small parent arteries (<2.5 mm).

Methods

We performed a retrospective study to identify 131 patients with aneurysms arising from small parent arteries treated with Leo Baby stent-assisted coiling in a single institution between October 2018 and June 2021. We assessed the immediate and progressive aneurysm occlusion rates, procedure-related complications, and clinical outcomes.

Results

A total of 131 patients with 135 aneurysms were identified, including 65 (48.1%) cases of acutely ruptured aneurysms. Technical success was achieved in all cases (100%). The immediate angiography showed complete occlusion in 111 aneurysms (82.2%), neck remnants in 19 (14.1%), and residual sac in 5 (3.7%). Procedure-related complications occurred in 14 cases (10.3%), including 13 (9.6%) thromboembolic complications and 1 (0.7%) hemorrhagic complication. Six-month follow-up angiography was achieved in 106 (78.5%) aneurysms, which showed complete occlusion in 102 (96.2%) aneurysms, neck remnants in 2 (1.9%), and residual sac in 2 (1.9%). Clinical follow-up was available in all patients with a median duration of 6.8 months, and favorable clinical outcomes (modified Rankin Scale score: 0–2) reached 91.6%. The mortality rate was 4.6%.

Conclusion

Our results demonstrate that stent-assisted coiling of intracranial aneurysms located on small arteries using LEO Baby stents is technically feasible, highly effective, and has midterm durability in aneurysmal occlusion.

Safety and Efficacy of Stent-Assisted Coiling of Unruptured Intracranial Aneurysms Using Low-Profile Stents in Small Parent Arteries

BACKGROUND AND PURPOSE

Stent-assisted coiling of intracranial aneurysms arising from small vessels (≤ 2.0 mm) is a common procedure. However, data regarding its treatment outcomes are scarce. This study evaluated the clinical and radiologic outcomes of stent-assisted coiling using low-profile stents for aneurysms of small parent arteries.

MATERIALS AND METHODS

From November 2015 to October 2020, sixty-four patients with 66 aneurysms arising from parent arteries of ≤2.0 mm were treated with stent-assisted coiling using a Low-Profile Visualized Intraluminal Support Junior (LVIS Jr) or the Neuroform Atlas stent in a single institution. The clinical and radiologic data were retrospectively reviewed, and the risk factors for procedure-related complications were evaluated.

RESULTS

The LVIS Jr and Neuroform Atlas stents were used in 22 (33.3%) and 44 (66.7%) cases, respectively. Technical success was achieved in 66 cases (100%). Immediate postprocedural aneurysm occlusion grades assessed by the Raymond-Roy occlusion classification were I (57.6%), II (19.7%), and III (22.7%), respectively. Procedure-related complications occurred in 10 cases (15.2%), with 8 thromboembolic complications (12.1%) and 2 hemorrhagic complications (3.0%). Procedure-related morbidity was 4.5% without mortality. On multivariate analysis, current smoking (odds ratio = 7.1, P = .021) had a statistically significant effect on procedure-related complications.

CONCLUSIONS

Stent-assisted coiling of intracranial aneurysms with low-profile stents in small vessels (≤ 2.0 mm) had a 100% success rate and a 15.2% overall complication rate with 4.5% morbidity. Current smoking was a significant risk factor associated with procedure-related complications.

Correlation Between Vascular Geometry Changes and Long-Term Outcomes After Enterprise Stent Deployment for Intracranial Aneurysms Located on Small Arteries

BACKGROUND

Enterprise stents are widely used for intracranial aneurysms located on small arteries (<2.5 mm in diameter) and change the geometry of parent arteries. The purpose of this study was to investigate the correlation between vascular geometry changes and long-term outcomes.

METHODS

Between May 2013 and 2018, 1065 consecutive intracranial aneurysms were treated with Enterprise stents at our institution. After inclusion and exclusion criteria were applied, 377 aneurysms with >6 months of digital subtraction angiography follow-up were evaluated. The cohort comprised 101 aneurysms located on small parent arteries. After stent-assisted coiling, the vascular geometry parameters of small parent arteries were compared to explore their correlation with procedural complications, delayed stent migration, and recanalization.

RESULTS

The rate of delayed aneurysm occlusion in patients with initial efferent artery diameter (De) <2.5 mm was significantly higher than in patients with De >2.5 mm (62.2% vs. 40.2%; P = 0.032). At follow-up, vascular geometry parameters significantly increased (P < 0.001). In multivariate analyses, larger aneurysms and initial parent artery angle (α) <90° were independent predictors of procedural complications and discrepancy in vessel size (ΔD) >0.5 mm was an independent predictor of delayed stent migration. Larger aneurysms and follow-up angle change (ΔAngle) <30° were independent predictors for recanalization of aneurysms located on small arteries.

CONCLUSIONS

Enterprise stent-assisted coiling of intracranial aneurysms located on small arteries is safe and effective. Our study found that Enterprise deployment in small arteries had a low procedural complication rate and high stent tolerance. Vascular geometry changes play an important role in aneurysm recanalization.

Clinical and Angiographic Outcomes After Stent-Assisted Coiling of Cerebral Aneurysms With Laser-Cut and Braided Stents: A Comparative Analysis of the Literatures

Introduction: Stent-assisted coiling (SAC) plays an important role in endovascular treatment of intracranial aneurysms (IAs). This comparative analysis examines the safety and efficacy of SAC in general and compares clinical and angiographic outcomes between laser-cut stents and braided stents.

Methods: Relevant English-language studies were identified via a PubMed search for published articles regarding outcomes of SAC using laser-cut stents and braided stents published from 2015 to 2020. Data from 56 studies that met our inclusion criteria were pooled and statistically compared.

Results: A total of 4,373 patients harboring with 4,540 IAs were included. Patients were divided into two groups on the basis of stent type: laser-cut stents (2,076 aneurysms in 1991 patients; mean follow-up, 12.99 months) and braided stents (2,464 aneurysms in 2382 patients; mean follow-up, 18.41 months). Overall, the rates of successful stent deployment, thromboembolic events, stent stenosis, periprocedural intracranial hemorrhage, permanent morbidity, mortality, and recanalization were 97.72, 4.72, 2.87, 1.51, 2.14, 1.16, and 6.06%, respectively. Laser-cut stents were associated with a significantly higher rate of successful deployment (p = 0.003) and significantly lower rate of periprocedural intracranial hemorrhage (p = 0.048). Braided stents were associated with a significantly lower rate of permanent morbidity (p = 0.015).

Conclusion: SAC of IAs using laser-cut stents or braided stents was effective and safe. Rates of thromboembolic events, stent stenosis, mortality, and recanalization were comparable between the stent types. Braided stents were associated with lower permanent morbidity while laser-cut stents were associated with more favorable rates of successful deployment and periprocedural intracranial hemorrhage.

Safety and efficacy of the Low-Profile Visualized Intraluminal Support stent in treating intracranial atherosclerotic stenosis

PURPOSE

The performance of the Low-Profile Visualized Intraluminal Support (LVIS) stent deployed following balloon angioplasty is unknown in treating intracranial atherosclerotic stenosis, and this study was to investigate the safety and efficacy of the LVIS stent in treating intracranial atherosclerotic stenosis in the middle cerebral artery M1 segment.

METHODS

Thirty-five patients were enrolled with 35 atherosclerotic stenoses at the M1 segment. The stenosis was about 75% in 16 patients, 80% in 15, and 90% in the rest four. The LVIS stent was used to treat these patients.

RESULTS

The success rate of stenting was 97.1%. The stenting procedure was failed in one patient because of intraprocedural dissection of the stenotic (75%) segment, resulting in a 30-day periprocedural complication rate of 2.9% (1/35). Before stenting, the stenosis rate ranged 75%-90% (mean 78.9%±4.7%), and after stenting, the diameter of the stented segment was significantly (P<0.0001) increased to 1.5-3.4mm (mean 2.1±0.32mm) ranging 68.2%-100% (mean 94.0%±5.8%) of the normal arterial diameter, with the residual stenosis ranging 0-31.8% (median 4.8%, IQR 2.4%-7.3%). Follow-up was performed at 6-20 months (mean 8.5) after stenting. One patient (2.9%) had occlusion of the stented M1 segment with no symptoms, and two patients (5.7%) had slight asymptomatic instent stenosis (40%) at the M1 segment, with the instent restenosis and occlusion rate of 8.6% (3/35).

CONCLUSION

The braided LVIS stent can be safely applied for treatment of intracranial atherosclerotic stenosis in the middle cerebral artery with good safety and efficacy immediately after stenting and at follow-up.

Endovascular deep brain stimulation: Investigating the relationship between vascular structures and deep brain stimulation targets

BACKGROUND

Endovascular delivery of current using 'stentrodes' - electrode bearing stents - constitutes a potential alternative to conventional deep brain stimulation (DBS). The precise neuroanatomical relationships between DBS targets and the vascular system, however, are poorly characterized to date.

OBJECTIVE

To establish the relationships between cerebrovascular system and DBS targets and investigate the feasibility of endovascular stimulation as an alternative to DBS.

METHODS

Neuroanatomical targets as employed during deep brain stimulation (anterior limb of the internal capsule, dentatorubrothalamic tract, fornix, globus pallidus pars interna, medial forebrain bundle, nucleus accumbens, pedunculopontine nucleus, subcallosal cingulate cortex, subthalamic nucleus, and ventral intermediate nucleus) were superimposed onto probabilistic vascular atlases obtained from 42 healthy individuals. Euclidian distances between targets and associated vessels were measured. To determine the electrical currents necessary to encapsulate the predefined neurosurgical targets and identify potentially side-effect inducing substrates, a preliminary volume of tissue activated (VTA) analysis was performed.

RESULTS

Six out of ten DBS targets were deemed suitable for endovascular stimulation: medial forebrain bundle (vascular site: P1 segment of posterior cerebral artery), nucleus accumbens (vascular site: A1 segment of anterior cerebral artery), dentatorubrothalamic tract (vascular site: s2 segment of superior cerebellar artery), fornix (vascular site: internal cerebral vein), pedunculopontine nucleus (vascular site: lateral mesencephalic vein), and subcallosal cingulate cortex (vascular site: A2 segment of anterior cerebral artery). While VTAs effectively encapsulated mfb and NA at current thresholds of 3.5 V and 4.5 V respectively, incremental amplitude increases were required to effectively cover fornix, PPN and SCC target (mean voltage: 8.2 ± 4.8 V, range: 3.0-17.0 V). The side-effect profile associated with endovascular stimulation seems to be comparable to conventional lead implantation. Tailoring of targets towards vascular sites, however, may allow to reduce adverse effects, while maintaining the efficacy of neural entrainment within the target tissue.

CONCLUSIONS

While several challenges remain at present, endovascular stimulation of select DBS targets seems feasible offering novel and exciting opportunities in the neuromodulation armamentarium.

Effects of acute angle, proximal bending, and distal bending in the deployment vessels on incomplete low-profile visualized intraluminal support (LVIS) expansion: an in vitro study

BACKGROUND

A low-profile visualized intraluminal support (LVIS) device may incompletely expand during stent deployment in tortuous vessels. However, the cause of incomplete expansion remains uninvestigated. We aimed to examine in vitro the factors causing incomplete expansion in LVIS deployment by using various vessel models.

METHODS

A linear model group was created by connecting linear silicone tubes (inner diameter 4 mm) at both sides of the LVIS deployment vessel (inner diameter 4 mm) with different curvature angles of 10-140° at 10° intervals. For comparison, proximal and distal bending model groups were created, both with 90° bending on the proximal/distal larger curvature side of the deployment vessel. A single operator macroscopically deployed an LVIS (4.5×32 mm) four times in each model and 56 times in each group.

RESULTS

In each model group the LVIS deployment vessel with a narrow curvature angle incompletely expanded. Incomplete expansion occurred significantly more frequently in the distal bending model group (34%, 19/56) compared with that in the linear model group (14.3%, 8/56; p<0.001), as well as in the proximal bending model group (59%, 33/56) compared with that in the distal bending model group (p<0.05). Compared with the linear model group, the proximal bending model group had a significantly reduced angle between the LVIS and the direction of the LVIS pushing force, but no significant change was found in the distal bending model group compared with that in the linear model group.

CONCLUSIONS

Factors such as acute angle, distal bending, and proximal bending of the deployment vessel can cause incomplete LVIS expansion.

The use of single low-profile visualized intraluminal support stent-assisted coiling in the treatment of middle cerebral artery bifurcation unruptured wide-necked aneurysm

OBJECTIVE

Endovascular treatment of unruptured wide-necked aneurysms located at the middle cerebral artery bifurcation remains challenging. This study aimed to evaluate the safety and efficacy of endovascular treatment for middle cerebral artery bifurcation unruptured wide-necked aneurysms using a low-profile visualized intraluminal support (LVIS) stent.

METHODS

We retrospectively reviewed all patients with middle cerebral artery bifurcation unruptured wide-necked aneurysms treated using an LVIS device at our institution between October 2014 and December 2018. Clinical presentation, aneurysmal characteristics, technical feasibility, perioperative complications, clinical outcome, and angiographic and clinical follow-up results were evaluated.

RESULTS

Fifty-seven patients with 57 wide-necked aneurysms arising from the middle cerebral artery bifurcation were identified. The technical success rate of stent deployment was 100%. Immediate postoperative angiograms showed Raymond 1 in 26 aneurysms (45.6%), Raymond 2 in 10 (17.6%), and Raymond 3 in 21 (36.8%). Perioperative complications developed in two patients (3.5%), including one procedure-related hemorrhagic event and one thromboembolic event. The follow-up angiogram was available for 47 aneurysms obtained at an average of 11.7 months (range, 5 to 49 months) after intervention; the latest follow-up angiograms revealed complete occlusion in 37 (78.7%) aneurysms, improvement in three (6.4%), stabilization in five (10.6%), and recanalization in two (4.3%). During the follow-up, one patient was found to have in-stent stenosis and two patients were found to have slow flow or occlusion of the jailed branch. All three of these patients were asymptomatic. No hemorrhagic or thromboembolic events occurred during clinical follow-up.

CONCLUSIONS

Our experience suggests that endovascular treatment of middle cerebral artery bifurcation unruptured wide-necked aneurysms with an LVIS stent is safe and effective, but the effect on branches needs to be further studied.

Application of High-Resolution C-Arm CT Combined with Streak Metal Artifact Removal Technology for the Stent-Assisted Embolization of Intracranial Aneurysms

BACKGROUND AND PURPOSE

Metal artifacts from coils and stents limit the level of detail in C-arm CT images of stent attachment and coiling attenuation in the aneurysm neck. We evaluated the utility of high-resolution C-arm CT combined with streak metal artifact removal technology for stent-assisted embolization of intracranial aneurysms.

MATERIALS AND METHODS

From October 2017 to July 2018, the First Affiliated Hospital of Zhengzhou University treated 107 patients with intracranial aneurysms (118 aneurysms in total) with stent-assisted embolization. Conventional C-arm CT and high-resolution C-arm CT scanning of the stented area were performed during and after treatment. 3D images were reconstructed with and without streak metal artifact removal techniques. Subsequently, the image quality was compared. The reconstructed images indicated the stent deployment degree and packing density. Follow-up assessments included clinical and angiographic outcomes and complications.

RESULTS

In total, 118 aneurysms were successfully embolized using 118 stents. Image quality was significantly higher (P < .05) with high-resolution C-arm CT combined with streak metal artifact removal reconstruction. Streak metal artifact removal reconstruction and 2D angiography at working angles showed incomplete deployment of 6 stents and incomplete aneurysm embolization of 15 patients, which were subsequently resolved. One case of hemorrhage was noted postoperatively. Follow-up of 93 patients at 6-13 months indicated 3 cases of aneurysm recurrence.

CONCLUSIONS

High-resolution C-arm CT combined with the streak metal artifact removal technique effectively reduced metal artifacts from stents and coils during aneurysm embolization. This method can help physicians determine the extent of stent deployment and the packing density of coils and thus potentially reduce complications and aneurysm recurrence.

Feasibility and midterm outcomes of endovascular embolization for true posterior communicating artery aneurysms

PURPOSE

Endovascular treatment (EVT) of true posterior communicating artery (PcomA) aneurysms has been rarely reported. This study reports the outcomes on a single-center cohort with true PcomA aneurysms who underwent EVT.

METHODS

Between June 2011 and June 2017, clinical data from 42 patients with 43 true PcomA aneurysms who underwent EVT were retrieved from a prospectively maintained single-center database. Endovascular techniques, perioperative complications, clinical outcomes, and angiographic results were retrospectively evaluated.

RESULTS

All aneurysms were treated successfully. Treatment modalities included simple coiling in 30 aneurysms, balloon-assisted coiling in two, and stent-assisted coiling in 11 cases. Immediate angiograms showed complete occlusion in 23 aneurysms (53.5%), residual neck in 8 cases (18.6%), and residual sac in 12 (27.9%). No procedure-related complications or mortality were observed. Of the 34 aneurysms that underwent angiographic follow-up at an average duration of 7.1 months post-procedure, complete occlusion was achieved in 22 (64.7%), neck remnant in eight (23.5%), and residual sac in four (11.8%) aneurysms, respectively. Six aneurysms (18.2%) that underwent conventional coiling developed recanalization and required retreatment. Seven cases that received stent-assisted coiling did not develop recurrence. Clinical follow-up (mean, 24.3 months) of all patients demonstrated no neurologic deterioration or (re)bleeding.

CONCLUSION

EVT of the true PcomA aneurysm is a safe and feasible procedure but may be associated with recurrence in midterm follow-up, requiring close surveillance and potential retreatment.

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.

Stent-assisted coil embolization of anterior communicating artery aneurysms using the LVIS Jr stent

BACKGROUND AND PURPOSE

This retrospective study evaluates the safety and mid-term and long-term effectiveness of stent-assisted coil embolization of anterior communicating artery (Acomm) aneurysms treated with the LVIS Jr stent.

MATERIALS AND METHODS

All patients treated with the LVIS Jr stent for Acomm aneurysms between June 2015 and March 2018 were included in the analysis. Details of the procedure's periprocedural adverse events, immediate aneurysm occlusion rates, and clinical and angiographic follow-up assessment were collected.

RESULTS

A total of 25 patients with 25 aneurysms were included. Eighteen aneurysms were found incidentally. Seven patients presented with seven ruptured aneurysms: Six were remotely ruptured and one acutely ruptured. Twenty-four patients were treated successfully and one technical failure is reported. The parent arteries measured 1.4 mm to 2.9 mm in diameter (mean, 2.3 mm). Intraprocedural thromboembolic complications occurred in two patients (8%) and an intraoperative aneurysm rupture in one patient (4%). Immediate complete aneurysm occlusion was noted in 18 out of 25 patients (72%). Clinical follow-up ranged from three months to 36 months (mean, 15.8 months) and the imaging follow-up ranged from two to 35 months (mean, 14.2 months). Complete aneurysm occlusion was achieved in 14 out of 20 patients (70%) at last angiographic follow-up. Of the two patients with in-stent thrombosis, one patient had an acutely ruptured aneurysm and the other patient was treated with an LVIS Jr stent in a Y configuration. Neurological morbidity and mortality rate were 0%.

CONCLUSIONS

Complex, wide-necked Acomm aneurysms can be effectively treated with stent-assisted embolization using LVIS Jr stents.

Is Single Low-Profile Visualized Intraluminal Support (LVIS)-Assisted Coiling of Wide-Necked Ruptured Multiple Intracranial Aneurysms in One Stage Feasible?

OBJECTIVE

There is no previous reports available on stent-assisted coiling of ruptured multiple intracranial aneurysms using single Low-Profile Visualized Intraluminal Support (LVIS) in one stage. In the present study, we investigated the efficacy and feasibility of using single LVIS to bridge multiple intracranial aneurysms in one stage.

METHODS

From April 2014 to August 2016, 24 patients treated with single LVIS to bridge 2 aneurysms in one stage were reviewed. The aneurysm morphology, clinical outcome, angiographic results, progressive occlusion, recurrence, and procedure-related complications were analyzed retrospectively.

RESULTS

In the present study, middle term clinical outcome showed that 9 patients were had a modified Rankin Scale (mRS) score of 0, 11 patients had mRS 1, and 4 patients had mRS 2. A total of 20 patients (83.3%) achieved a good outcome, 4 patients (16.7%) had poor outcomes, and 7 of 18 patients (38.9%) displayed improved clinical neurologic status in long-term follow-up. Immediate angiographic results postprocedure showed Raymond Scale (RS) I in 33 aneurysms (68.8%), RS II in 11 aneurysms (22.9%), and RS III in 4 aneurysms (8.3%). The angiographic follow-up results showed RS I in 41 aneurysms (85.4%), RS II in 5 aneurysms (10.4%), and RS III in 2 aneurysms (4.2%). Of 15 incomplete occlusion aneurysms postprocedure, 10 aneurysms (66.7%) achieved to progressed occlusion on follow-up imaging, and no recanalization or mortality occurred in this group.

CONCLUSIONS

Single LVIS bridging wide-neck ruptured multiple intracranial aneurysms was effective and feasible in one stage. However, the procedure-related complications should be emphasized and long-term follow-up requires further evaluation.

Long-Term Outcomes of Patients with Stent Tips Embedded into Internal Carotid Artery Branches during Aneurysm Coiling

BACKGROUND AND PURPOSE

During stent-assisted coiling of ICA aneurysms, stent tips are sometimes unintentionally embedded into ICA branches. Stent tips can be visualized because they have radiopaque markers. Concerns regarding stent tip misplacement include risks of artery perforation and occlusion. The aim of this study was to evaluate the long-term outcomes of ICA branches with embedded stent tips.

MATERIALS AND METHODS

ICA branches with embedded stent tips were identified among 35 patients with unruptured ICA aneurysms treated with stent-assisted coiling between November 2003 and November 2014. Patient clinical and angiographic outcomes associated with the embedded stent tip were analyzed.

RESULTS

Most of the 35 studied aneurysms were paraclinoid ICA aneurysms (n = 30). The most commonly involved ICA branch was the posterior communicating artery (26 patients, 74.3%), followed by the anterior choroidal artery (8 patients, 22.9%) and ophthalmic artery (1 patient, 2.9%). During the follow-up period (38.6 ± 17.9 months), no new neurologic deficits developed. Neither hemorrhagic nor thromboembolic events occurred. Angiography was performed during the final follow-up evaluation at a mean of 32.7 ± 18.0 months, and all ICA branches with embedded stent tips showed patent blood flow without severe luminal narrowing.

CONCLUSIONS

In our experience, placement of a stent tip into ICA branches during stent-assisted coiling was not associated with any major adverse events.

LVIS Jr. stent for treatment of intracranial aneurysms with parent vessel diameter of 2.5 mm or less

Background and purpose This retrospective study evaluates the safety, effectiveness, and long-term clinical and angiographic follow-up of intracranial aneurysms treated with the Low-Profile Visualized Intraluminal Support Junior (LVIS Jr.) stent and parent vessels of diameter equal to or less than 2.5 mm. Materials and methods We included all patients treated with the LVIS Jr. stent in aneurysms with small parent vessel diameter between March 2015 and July 2017. Periprocedural adverse events, immediate aneurysm occlusion rates, and clinical and angiographic follow-up are reported. Results A total of 35 patients with 35 aneurysms were included. Ten aneurysms were ruptured (28.6%) and 25 were unruptured (71.4%). The parent arteries measured 0.9 mm to 2.5 mm in diameter (mean, 2.2 mm). Intra-procedural thromboembolic complications occurred in four patients (11.4%) and there was an intraoperative aneurysm rupture in one patient (2.8%). Immediate complete aneurysm occlusion was noted in 21 out of 35 patients (60%). Clinical follow-up ranged between one and 25 months (mean, 10.5 months) and magnetic resonance angiography follow-up ranged between four and 24 months (mean, 10.4 months). Complete aneurysm occlusion was achieved in 21 out of 29 patients (72.4%) at last angiographic follow-up (mean, 9.4 months; range four to 23 months). In-stent stenosis occurred in one out of 29 patients (3.4%), who was asymptomatic. Of the four patients with in-stent thrombosis, three patients were treated with "Y configuration" (two patients with middle cerebral artery aneurysms and one patient with an anterior communicating artery aneurysm). Mortality rate was 0%. Neurological morbidity was 2.9%. Conclusions Stenting with the LVIS Jr. stent allowed us to treat complex intracranial aneurysms with parent vessel diameter of 2.5 mm or less with an acceptable safety profile.

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.