Endovascular Retreatment Research Articles

Transradial stent angioplasty using double guide wires for severe stenosis of vertebral artery ostium at a lower location

To investigate the effect and safety of transradial stent angioplasty using double guide wires for severe stenosis of vertebral artery ostium at a lower location. Patients with severe stenosis of the vertebral artery ostium at a lower location treated with transradial stent angioplasty were retrospectively enrolled. All the clinical and endovascular treatment data were analyzed. Thirty-nine patients were enrolled. A low location of the vertebral artery ostium was present in 33 (84.6%) patients and an ultra-low location in 6 (15.4%). Transradial stent angioplasty was performed in all patients. In one patient who had a tortuous radial artery, the transradial access was failed. In the other 38 (97.4%) patients, transradial stent angioplasty was all successful. The sharp angle formed between the vertebral artery and the subclavian artery was significantly (P<0.0001) increased from 15°-65° (36°±11°) before to 70-125° (90°±17°) after insertion of a support guide wire. No damage was found in all support guide wires. Thirty-nine stents were deployed, and the preoperative stenosis rate of 70%-98% (85%±13%) was significantly (P<0.0001) decreased to 0-25% (16%) immediately after stenting. Six-12 months after surgery, 29 (74.4% or 29/39) patients were followed up with imaging, and nine (31.0%) patients experienced in-stent restenosis, with endovascular retreatment being performed in 3 (33.3%) patients. Transradial stent angioplasty using double guide wires is safe and effective for the treatment of severe stenosis of the vertebral artery ostium at a lower location even though more studies are necessary to confirm this.

Endovascular treatment of unruptured intracranial aneurysms with flow diverters: A retrospective long-term single center analysis.

The introduction of flow diverters (FDs) in 2007 greatly enhanced the treatment of intracranial aneurysms. Here, we present our long-term clinical experience in treating unruptured intracranial aneurysms with FDs. 107 patients with unruptured aneurysms and treated with an FD between 2010 and 2019 were retrospectively reviewed. Aneurysm occlusion, procedural complications, and clinical outcome were evaluated. Angiographic follow-up was available for 93 patients with a mean long-term follow-up time of 28.4 ± 21.6months. Additional coiling was performed in 15.1% of patients (n = 14). Adequate aneurysm occlusion (Kamran grades 3 and 4) at long-term follow-up was achieved in 94.6% of patients (n = 88). 3.2% (n = 3) required endovascular retreatment since the last follow-up showed a lack of aneurysm occlusion (Kamran grade 0) due to a foreshortening of the FD. Incomplete opening of the FD and parent vessel occlusion was seen in 1.1% (n = 1) and 3.2% (n = 3) of patients, respectively. In-stent stenosis was observed in 57% (n = 53) of cases at short-term follow-up and 22.6% (n = 21) at long-term, which were moderate and asymptomatic overall. In-stent stenosis decreased significantly between short- and long-term follow-ups (31.4 ± 17.0% vs 9.7 ± 13.6%, respectively; p ≤ 0.001). Thromboembolic and hemorrhagic events occurred in 7.5% (n = 7) and 1.1% (n = 1) of patients, respectively. Good clinical outcome (modified Rankin scale: 0-2) was obtained in 97.8% (n = 91) leading to an overall treatment-related morbidity of 2.2% (n = 2). There was no procedural mortality. Our study shows that FD treatment of unruptured intracranial aneurysms is effective and safe with high occlusion rates and low rates of permanent morbidity at long-term follow-up.

Treatment results and long-term outcomes of endovascular treatment of 96 unruptured anterior communicating artery aneurysms: A large single-center study

ObjectiveData on endovascular treatment of unruptured anterior communicating artery (AcomA) aneurysms remain limited. Therefore, to clarify the outcomes of treatment for unruptured AcomA aneurysms, we retrospectively analyzed a single-center series of 96 unruptured AcomA aneurysms treated endovascularly. MethodsEndovascular treatment of 100 unruptured AcomA aneurysms was performed at our institution between May 2009 and May 2019; of these, 96 consecutive aneurysms (95 patients) were included in this retrospective study. Recanalization and retreatment rates were investigated for 76 aneurysms through follow-up using time-of-flight magnetic resonance angiography or digital subtraction angiography for ≥ 2 years after treatment. ResultsThe rate of total procedure-related complications was 19.8%. The rates of thromboembolic complications, hemorrhagic complications, and intraprocedural aneurysm bleeding were 12.5%, 6.3%, and 3.1%, respectively, with no poor outcomes (modified Rankin Scale score 2–6) resulting from thromboembolic and hemorrhagic complications at 180 days after treatment. The permanent morbidity rate was 1.0%. Multivariate analysis revealed that maximum diameter (>10 mm), neck size (>4 mm), and stent use were independently associated with symptomatic cerebral infarction. Endovascular retreatment was conducted for two aneurysms (2.6%), and the cumulative recanalization rate was 5.3% (4/76) over a mean follow-up period of 48.2 ± 23.7 months. ConclusionThis study indicates that although there is a relatively high possibility of overall procedure-related complications with endovascular treatment for unruptured AcomA aneurysms, most complications are temporary and mild, with a permanent morbidity rate of approximately 1.0%.

Retreatment With Flow Diverters and Coiling for Recurrent Aneurysms After Initial Endovascular Treatment: A Propensity Score-Matched Comparative Analysis.

Background: Flow diverters and conventional coiling are established modalities for the retreatment of intracranial recurrent aneurysms after initial endovascular treatment. We aimed to compare the efficacy of these techniques.Methods: We retrospectively analyzed data for patients with recurrent aneurysms after initial endovascular treatment retreated in our center with either a pipeline embolization device (PED) or conventional coil embolization from January 2012 to July 2020. We performed 1:2 propensity score matching (PSM) using the nearest neighbor method. We controlled for: initial treatment strategy, aneurysm size, neck diameter, symptom presentation, history of aneurysm rupture, age, sex, fusiform-dissecting aneurysm, bifurcation aneurysm, and aneurysm location. The clinical and morphological factors of all patients at initial treatment and the angiographic and clinical results at the second treatment were collected and compared between the propensity-matched pairs.Results: A total of 105 intracranial aneurysms were identified; 18 patients (17.1%) were treated with a PED, and 87 (82.9%) were treated via conventional coil embolization. PSM resulted in 12 matched pairs (12 patients in the PED group and 24 in the coiling group). There was no significant difference of ischemic and hemorrhagic complications between the groups, the obliteration rate of branches covered by stent, or modified Rankin Scale scores at the last clinical follow-up. Importantly, the retreatment strategy in the PED group provided significantly different results vs. the coiling group (P < 0.001), with a lower recurrence rate (0.0 vs. 29.2%, respectively; P = 0.037). However, the procedural failure rate and the parent artery stenosis were more frequently in PED group compared with coiling group (both were 16.7 vs. 0.0%; P = 0.040).Conclusions: Endovascular retreatment for recurrent aneurysms after initial endovascular treatment might be safe and effective. Flow diverters might be associated with reduced risk of recanalization and an increased risk of procedural failure and mild parent artery stenosis.

Endovascular Retreatment of Previously Ruptured Coiled Cerebral Aneurysm Remnants Significantly Reduces Rebleed Rate

Treatment of ruptured cerebral aneurysms by endovascular coiling is associated with a better neurologic outcome when compared with neurosurgical clipping but has a higher risk for target aneurysm rebleeding after treatment. We hypothesize that aggressive retreatment of coiled aneurysms will lead to fewer recurrent hemorrhages as compared with historical values of 2.3%-3.0%. All first-time Guglielmi detachable coil-embolized cerebral aneurysms were retrospectively reviewed at a single institution from 2004 to 2015. Aneurysm retreatment after first-time embolization was recorded as well as time to retreatment. Retreatment at our institution is routinely performed for incomplete coiling with etiologies including incomplete initial coiling, coil compaction, and aneurysmal dilatation. Aneurysm rerupture was treated with additional coiling. Kaplan-Meier survival analysis was performed to evaluate embolization durability. There were 214 aneurysms that met inclusion criteria. Mean (standard deviation) follow-up was 2.74 (2.24) years. Aneurysms that were patent or recanalized were retreated. Mean (standard deviation) time to retreatment was 9 (9) months. Overall, 46 (21.5%) aneurysms required retreatment. Retreatment was performed for coil compaction/remnant growth, recanalization, persistent remnant, and rebleed. Two (0.9%) patients had recurrent aneurysm hemorrhage and both were treated with additional coil embolization. There were no new long-term neurologic deficits caused by aneurysm retreatment. Aggressive retreatment of previously ruptured, coiled cerebral aneurysms for persistent aneurysm patency reduces the recurrent hemorrhage risk to that historically seen in neurosurgically clipped aneurysms with minimal additional morbidity. This study validates a large body of literature demonstrating the significance of post-treatment aneurysm remnants and their association with recurrent hemorrhage.

Outcome of retreatment for recurrent saccular cerebral aneurysms: a propensity score-matched analysis.

Although endovascular or surgical treatment has been performed for preventing the rupture of saccular cerebral aneurysms (sCA), in some patients, the aneurysms may recur and require retreatment. We aimed to investigate the clinical and radiological outcomes of treating recurrent sCA. We retrospectively evaluated the data of 52 patients with 60 recurrent sCAs who were retreated and 1534 patients with 1817 sCAs who received initial treatment. The primary outcome was a recurrence of the aneurysm. Secondary outcomes were an additional treatment, rupture after treatment, and a neurological worsening, which was defined as an increase of 1 or more scores using the modified Rankin Scale at 12-month. Safety outcomes included postoperative ischemic and hemorrhagic complications. We compiled the 120 (60 each) propensity score-matched cohort based on a propensity score for the treatment of recurrent sCA. In the propensity score-matched cohort, recurrence after treatment was observed in 25% and 6.7% of cases in the retreatment and initial treatment groups, respectively. The odds ratio of recurrence after treatment was 4.7 (95% CI, 1.4-15; P = 0.011). The secondary and safety outcomes were not significantly different between the two groups. This study showed that the treatment of recurrent sCA was a risk factor for recurrence after treatment but not for additional treatment, rupture after treatment, or neurological worsening. Although decision-making regarding the treatment varies depending on the institutional protocols and personal experience of the physicians, endovascular or surgical retreatment could be performed without hesitation.

Factors affecting recurrence and management of recurrent cerebral aneurysms after initial coiling.

To investigate factors affecting recurrence and effects and safety of endovascular retreatment for aneurysms recurrent after embolization. Among 815 aneurysms treated with embolization, recurrence was in 114 aneurysms (14.0%). Forty-three recurrent aneurysms were managed with re-embolization. Procedural complications, angiographic, and clinical results of retreatment were analyzed. Patients with recurrent aneurysms were significantly (P < 0.01) younger than without recurrence (51.09 ± 10.46 vs. 53.88 ± 9.61 years). Recurrent aneurysms (n = 114) were significantly (P = 0.00) greater (11.12 ± 8.35 vs. 5.81 ± 3.44 mm) with a significantly (P = 0.00) greater neck (4.34 ± 2.26 vs. 2.90 ± 1.44 mm) than without recurrence. The rupture status of aneurysms significantly (P = 0.00) affected recurrence at follow-up. Significantly (P = 0.00) more aneurysms without recurrence were treated with advanced embolization techniques (81.0% vs. 62.3%) and got complete occlusion at the first embolization than those with recurrence (93.7% vs. 36.8%). In treating 43 recurrent aneurysms, stent-assisted recoiling was used in 48.8% in the first retreatment and 50% in the second and third retreatment procedures. Angiographic follow-up in 38 (88.4%) cases showed complete or near complete occlusion in 30 aneurysms, with the rest eight aneurysms experiencing a second recurrence (21.1%). Of the eight aneurysms with the second recurrence, five underwent the second endovascular retreatment, with complete aneurysm occlusion achieved in three cases (60%), near-complete occlusion in one (20%), and incomplete occlusion in one case at immediate angiography and six-month follow-up. Procedure-related complications occurred in three patients. Endovascular retreatment of recurrent previously coiled aneurysms is safe and effective even though advanced embolization techniques are frequently involved especially for large and giant aneurysms.

Outcomes of Retreatment for Intracranial Aneurysms - A Meta-Analysis.

Long-term results from the International Subarachnoid Hemorrhage Trial (ISAT) and Barrow Ruptured Aneurysm Trial (BRAT) indicate considerably higher retreatment rates for aneurysms treated with coiling compared to clipping, but do not report the outcome of retreatment. To evaluate retreatment related outcomes. A meta-analysis in accordance with PRISMA guidelines was conducted using Medline search engines PubMed and EMBASE to identify articles describing outcomes after retreatment for intracranial aneurysms. Pooled prevalence rates for complete occlusion rate and mortality were calculated. Outcomes of different treatment and retreatment combinations were not compared because of indication bias. Twenty-five articles that met the inclusion criteria were included in the meta-analysis. Surgery after coiling had a pooled complete occlusion rate of 91.2% (95% confidence interval [CI]: 87.0-94.1) and a pooled mortality rate of 5.6% (95% CI: 3.7-8.3). Coiling after coiling had a pooled complete occlusion rate of 51.3% (95% CI: 22.1-78.0) and a pooled mortality rate of 0.8% (95% CI: 0.15-3.7). Surgery after surgery did not provide a pooled estimate for complete occlusion as only one study was identified but had a pooled mortality rate of 5.9% (95% CI: 3.1-11.2). Coiling after surgery had a pooled complete occlusion rate of 56.1% (95% CI: 11.4-92.7) and a pooled mortality rate of 9.3% (95% CI: 4.1-19.9). All pooled incidence rates were produced using random-effect models. Surgical retreatment was associated with a high complete occlusion rate but considerable mortality. Conversely, endovascular retreatment was associated with low mortality but also a low complete occlusion rate.

Endovascular Retreatment of Cerebral Aneurysms Previously Treated with Endovascular Embolization.

Intracranial aneurysms treated with endovascular coil embolization may recur. We investigated the factors affecting aneurysmal recurrence after embolization and effects of endovascular retreatment within 1 year. In 3 years, 1,335 patients with 1,385 intracranial aneurysms were treated with coil embolization. Factors affecting aneurysm recurrence and the effects of endovascular retreatment were analyzed. Angiography immediately following embolization showed total occlusion in 1,030 aneurysms (74.4%), neck remnant in 207 (14.9%), and partial occlusion in 148 (10.7%), with a total peri-procedure complication rate of 4.2%. Overall, 145 patients with 151 aneurysms recurred within 1 year and the other 1,234 aneurysms remained occluded (89.1%). A significant (p < 0.05) difference existed in aneurysm size, rupture status, use of stent and immediate occlusion outcome between the two groups, with significantly (p < 0.05) lower recurrence rates in aneurysms with smaller sizes, no rupture and stent-assistance coiling. Neck remnant, partial occlusion, coiling without stent assistance, large and giant aneurysms were significant (p < 0.05) risk factors for aneurysm recurrence during the first year. The rate of recurrence was 4.7% (11/232) in aneurysms with total occlusion and 35.9% (23/64) in aneurysms with neck remnant and partial occlusion. Of the 34 recurrent aneurysms, 6 were re-embolized with detachable coils alone, 12 with stent-assisted coiling, 8 with balloon-assisted embolization, and the remaining 8 aneurysms with covered stents, resulting in total occlusion in 28 aneurysms and neck remnant in 6. Recurrence of previously-coiled cerebral aneurysms is significantly affected by aneurysm size, use of stent and degree of immediate occlusion. Endovascular retreatment with balloon-or stent-assisted techniques or with covered stents can be safe and effective for recurrent cerebral aneurysms.

Endovascular repair of late type IIIb endoleak after endovascular aneurysm repair: a case report

BackgroundType IIIb endoleak is a rare complication after endovascular aneurysm repair (EVAR) and the understanding of type IIIb endoleak is insufficient.Case presentationThree elderly patients with previously successfully performed EVARs were sent to our center due to abdominal pain and diagnosed with late type IIIb endoleak. The type IIIb endoleak fabric tears were closed with cuffs or stents by endovascular retreatment. The patients recovered adequately and were discharged from hospital.ConclusionsEndovascular repair with empirical relining could be a good choice for treatment of late type IIIb endoleak with good prognosis.

Treatment strategies for recurrent and residual aneurysms after Woven Endobridge implantation

BackgroundWoven Endobridge (WEB) embolization is a safe and efficient technique for endovascular treatment of intracranial aneurysms. However, the management of aneurysm recurrence after WEB placement has not been well described...

Therapeutic strategies for residual or recurrent intracranial aneurysms after microsurgical clipping

ObjectivesTherapeutic strategies for residual or recurrent aneurysm (RRA) after microsurgical clipping have not been well established. The purpose of this study was to report our retreatment experiences with previously clipped aneurysms and to demonstrate retreatment strategies for these RRAs. Patients and MethodsFrom 1996–2016, we treated 68 RRAs after previous clipping. Among them, 34 patients underwent microsurgical retreatment, and the other 34 underwent endovascular retreatment. Radiographic images and clinical data were reviewed retrospectively to determine the treatment efficacy, clinical outcomes, and important factors for selecting the proper treatment modality. ResultsThe most common aneurysm location was the middle cerebral artery (50%) in the microsurgery group and the internal carotid artery (47.1%) in the endovascular surgery group (p = 0.001). In the microsurgery group, 16 (47.1%) patients had additional clipping without removal of previous clips, 17 (50.0%) had clipping with removal of previous clips, and 1 (2.9%) had bypass surgery with trapping. In the endovascular surgery group, 28 (82.4%) patients had simple coiling, 5 (14.7%) had stent-assisted coiling, and 1 (2.9%) had a flow diverter. Procedure-related complications during retreatment occurred in 4 (5.9%) patients. Complete obliteration was achieved in 51 (75.0%) patients (microsurgery group, 82.4% and endovascular surgery group, 67.6%; p = 0.002). ConclusionsIn properly selected cases, treatment of RRAs could be safely performed either by microsurgery or endovascular surgery and result in a good clinical outcome with acceptable morbidity. The decision to choose the treatment modality for RRAs after clipping is not easy but should be considered to lower the risk of retreatment.

Geographic Differences in Endovascular Treatment and Retreatment of Cerebral Aneurysms.

Comparing outcomes between endovascular aneurysm coiling trials can be difficult because of heterogeneity in patients and end points. We sought to understand the impact of geography on aneurysm retreatment in patients enrolled in the Matrix and Platinum Science Trial. Post hoc analysis was performed on data from the Matrix and Platinum Science trial. Patients were stratified as either North American or international. Baseline patient demographics, comorbidities, aneurysm characteristics, procedural complications, and clinical and angiographic outcomes were compared. We evaluated 407 patients from 28 North American sites and 219 patients from 15 international sites. Patient demographics differed significantly between North American and international sites. Aneurysms were well occluded postprocedure more often at international than North American sites (P < .001). Stents were used significantly more often at North American sites (32.7% [133 of 407]) compared with international sites (10.0% [22 of 219]; P < .001). At 455 days, there was no difference in the proportion of patients alive and free of disability (P = .56) or with residual aneurysm filling (P = .10). Ruptured aneurysms were significantly more likely to have been retreated at North American sites within the first year (P < .001) and at 2 years (P < .001). Among all patients for whom the treating physician believed there to be Raymond 3 aneurysm filling at follow-up, absolute rates of retreatment at international and North American sites were similar by 2-year follow-up. Data from the Matrix and Platinum Science Trial demonstrate that aneurysm retreatment occurs with different frequency and at different times in different regions of the world. This trend has critical value when interpreting trials reporting short-term outcomes, especially when judgment-based metrics such as retreatment are primary end points that may or may not take place within the defined study follow-up period. Though these variations can be controlled for and balanced within a given randomized trial, such differences in practice patterns must be accounted for in any attempt to compare outcomes between different trials. Despite these differences, endovascular-treated intracranial aneurysms around the world have similar clinical outcomes.

Predictors of success following endovascular retreatment of intracranial aneurysms.

Although approximately one in every 10 patients undergoing coil embolization of intracranial aneurysms requires retreatment, the factors that are associated with outcome following retreatment remain to be fully elucidated. This is a single-center, retrospective review of 43 patients with 58 intracranial aneurysms that were retreated from 2004 to 2014. Aneurysms undergoing first time or microsurgical retreatment were excluded. Retreatment types were grouped into those without permanent parent vessel support (stand-alone and balloon-assisted coiling) versus those with permanent parent vessel support (stent-assisted coiling, stand-alone stenting, and flow diversion). The Modified Raymond Roy Classification was used to group aneurysms at all angiographic follow-up points either in the successful outcome group (Class I or II) or the unsuccessful outcome group (Class IIIa or IIIb). Of aneurysms with follow-up, 50% were in the successful group and 50% in the unsuccessful group. In univariate analysis, small aneurysm size (p < 0.001), previous treatment type (p = 0.022), retreatment type (p = 0.001), and initial occlusion class (p = 0.005) were all associated with angiographic outcome. In multivariate analysis, small aneurysm size (p = 0.005, odds ratio (OR) 24.56, confidence interval (CI) 2.68-225.4) and retreatment type with permanent parent vessel support, namely stent-assisted coiling (p = 0.017, OR 31.1, CI 1.89-517.7), were associated with retreatment success. Small aneurysm size and retreatment with permanent parent vessel support, namely stent-assisted coiling, are predictors of success following endovascular retreatment of intracranial aneurysms. These findings could be useful in the effort to both prevent and predict treatment failure following endovascular retreatment.

Safety and predictors of aneurysm retreatment for remnant intracranial aneurysm after initial endovascular embolization

IntroductionAneurysmal subarachnoid hemorrhage (SAH) is a rare but devastating form of stroke. Endovascular therapy has been criticized for its higher rate of recanalization and retreatment. The safety and predictors of...

Does Stent Implantation Improve the Result of Repeat Embolization in Recanalized Aneurysms?

Although endovascular technique and related devices continue to improve, recanalization of embolized aneurysm remains a pitfall of this approach. The problem of how to treat the recanalized aneurysm needs to be addressed. To determine the outcomes of patients undergoing repeat embolization for recanalized intracranial aneurysms and to evaluate the impact of stent implantation on subsequent recanalization. Between September 2001 and September 2011, we performed endovascular retreatment in 162 patients with a total of 197 recanalized intracranial aneurysms. Stent implantation was performed in 68 aneurysms during the retreatment. Clinical and morphological outcomes were assessed at 6 months or more after repeat embolization. Procedure-related complications, including asymptomatic thromboembolism, occurred with 15 aneurysms (7.6%) without permanent neurological sequelae. Follow-up imaging of 172 aneurysms documented stable occlusion in 96 of the lesions (55.8%), minor recanalization in 17 (9.9%), and major recanalization in 59 (34.3%) during the mean follow-up period of 26.0 ± 18.0 months. In multiple logistic regression analysis, stent implantation was shown to reduce the major recanalization rate at 6 months after retreatment (odds ratio: 0.161; 95% confidence interval:, 0.038-0.670; P = .012) and thereafter (odds ratio: 0.226; 95% confidence interval: 0.088-0.581; P = .002). Stent implantation, as well as compact coil packing, at the time of repeat embolization seems beneficial in reducing rates of further recanalization.

Aneurysmal Subarachnoid Hemorrhage: An Overview for the Practicing Neurologist

Subarachnoid hemorrhage (SAH) accounts for ~5% of strokes, but causes high rates of morbidity and mortality and occurs at a relatively young age. The rupture of an intracranial aneurysm is the leading cause of nontraumatic SAH and will be the subject of this review. Rebleeding remains the most imminent danger until the aneurysm is secured (i.e., excluded from the cerebral circulation). Therefore, prompt aneurysm treatment is crucial to minimize this risk. Endovascular occlusion of the aneurysm with coils has been shown to be associated with better short- and long-term outcomes than surgical clipping in select patients. Yet, angiographic surveillance is necessary after endovascular treatment and retreatment with additional coiling may be required. Delayed cerebral vasospasm is the leading cause of brain damage once the aneurysm has been treated. Hemodynamic augmentation therapy remains the mainstay of medical treatment, but various agents are being tested as means to prevent or ameliorate vasospasm, including magnesium sulfate, statins, and an endothelin antagonist. Medically refractory vasospasm demands angioplasty of the affected vessel or intraarterial infusion of vasodilators. In this review, the authors provide an overview of the diagnosis and management of aneurysmal SAH with an emphasis on these main topics.

Waffle-cone technique with Solitaire™ AB Remodeling Device: endovascular treatment of highly selected complex cerebral aneurysms

To evaluate patients with complex aneurysms who underwent waffle-cone stent-assisted coil embolization. From February 2008 to February 2010, consecutive data were collected from 80 patients with aneurysms treated with the Solitaire™ AB Remodeling Device followed by a standard coiling procedure using bare or/and bioactive coils. Six of these patients were treated using the "waffle-cone-technique" placing the distal end of a stent directly into the base of a bifurcation aneurysm and coiling through the expanded and cone-shaped distal end of the stent allowing for preservation of parent artery patency. The aneurysms were located at the P3 segment of the posterior cerebral artery (n = 1), the middle cerebral artery bifurcation (n = 1), the basilar tip (n = 2), and the AComAnt (n = 2). Four patients underwent follow-up (2-7 months, mean 4.5 months). Waffle-cone positioning of the Solitaire™ AB Remodeling Device was obtained in all cases without technical problems. No permanent procedural morbidity was observed. In all patients, a Raymond class 2 occlusion was obtained and five patients left the hospital with a good clinical status (mRS0 n = 3, mRS1 n = 1) or no new neurologic deficits (mRS4 n = 1). One patient with SAH III died due to severe vasospasms. Due to major recanalization during follow-up, retreatment was necessary or is planned in four cases; one asymptomatic intimal hyperplasia was observed 8 weeks after initial treatment. The waffle-cone technique may enhance the possibilities of the endovascular treatment of these complex aneurysms. Due to the high rate of recanalization requiring endovascular retreatment, stringent angiographic and clinical follow-up is warranted.

REPEATED ENDOVASCULAR COIL OCCLUSION IN 350 OF 2759 INTRACRANIAL ANEURYSMS

Evaluation of the safety and effectiveness of endovascular retreatment of intracranial aneurysms with detachable coils.Retrospective analysis of clinical outcome as well as angiographic studies both before and after coil retreatment. The indication for retreatment was based on either inadequate occlusion after previous treatment or recurrent perfusion of the aneurysm.A total of 2759 intracranial aneurysms in 2360 patients were treated by endovascular coil occlusion. Of those, 350 (12.3%) aneurysms underwent a second treatment, and 94 (3.4%) aneurysms underwent three or more treatment sessions. The second treatment sessions were performed an average of 27.2 months after the previous procedure. The third and following treatment sessions were conducted an average of 25.3 months after the previous procedure. Initial treatment resulted in 100% occlusion in 63.7% of aneurysms. One hundred percent occlusion was achieved in only 46.9% of the second and 35.2% of the third and following sessions. Stent-assisted coil treatment was used in 5.6% of initial, 28.0% of second, and 20.7% of third and following sessions. Initial treatment sessions were uneventful in 83.2% of cases, second sessions in 86.9% of cases, and third and following sessions in 87.6% of cases. The morbidity-mortality rate for 495 retreatment sessions was 2.2% (n = 11).The natural course of aneurysm remnants or recurrent aneurysm perfusion after coil treatment is not completely understood. The low risk of bleeding from partially filled aneurysms must be balanced against the procedure-related risks of retreatment. Great caution is recommended for the treatment of asymptomatic recurrent aneurysms.

Repeated Endovascular Coil Occlusion in 350 of 2759 Intracranial Aneurysms: Safety and Effectiveness Aspects

Evaluation of the safety and effectiveness of endovascular retreatment of intracranial aneurysms with detachable coils. Retrospective analysis of clinical outcome as well as angiographic studies both before and after coil retreatment. The indication for retreatment was based on either inadequate occlusion after previous treatment or recurrent perfusion of the aneurysm. A total of 2759 intracranial aneurysms in 2360 patients were treated by endovascular coil occlusion. Of those, 350 (12.3%) aneurysms underwent a second treatment, and 94 (3.4%) aneurysms underwent three or more treatment sessions. The second treatment sessions were performed an average of 27.2 months after the previous procedure. The third and following treatment sessions were conducted an average of 25.3 months after the previous procedure. Initial treatment resulted in 100% occlusion in 63.7% of aneurysms. One hundred percent occlusion was achieved in only 46.9% of the second and 35.2% of the third and following sessions. Stent-assisted coil treatment was used in 5.6% of initial, 28.0% of second, and 20.7% of third and following sessions. Initial treatment sessions were uneventful in 83.2% of cases, second sessions in 86.9% of cases, and third and following sessions in 87.6% of cases. The morbidity-mortality rate for 495 retreatment sessions was 2.2% (n = 11). The natural course of aneurysm remnants or recurrent aneurysm perfusion after coil treatment is not completely understood. The low risk of bleeding from partially filled aneurysms must be balanced against the procedure-related risks of retreatment. Great caution is recommended for the treatment of asymptomatic recurrent aneurysms.