Association of masseter area and radiodensity with three-month survival after proximal anterior circulation occlusion.

BACKGROUND: Masseter area (MA), a surrogate for sarcopenia, appears to be useful when estimating postoperative survival, but there is lack of consensus regarding the potential predictive value of sarcopenia in acute ischemic stroke (AIS) patients. We hypothesized that MA and density (MD) evaluated from pre-interventional CT angiography scans predict postinterventional survival in patients undergoing mechanical thrombectomy (MT). MATERIALS AND METHODS: 312 patients treated with MT for acute occlusions of the internal carotid artery (ICA) or the M1 segment of the middle cerebral artery (M1-MCA) between 2013 and 2018. Median follow-up was 27.4 months (range 0-70.4). Binary logistic (alive at 3 months, OR <1) and Cox regression analyses were used to study the effect of MA and MD averages (MAavg and MDavg) on survival. RESULTS: In Kaplan-Meier analysis, there was a significant inverse relationship with both MDavg and MAavg and mortality (MDavg P<0.001, MAavg P=0.002). Long-term mortality was 19.6% (n=61) and 3-month mortality 12.2% (n=38). In multivariable logistic regression analysis at 3 months, per 1-SD increase MDavg (OR 0.61, 95% CI 0.41 to 0.92, P=0.018:) and MAavg (OR 0.57, 95% CI 0.35 to 0.91, P=0.019) were the independent predictors associated with lower mortality. In Cox regression analysis, MDavg and MAavg were not associated with long-term survival. CONCLUSIONS: In acute ischemic stroke patients, MDavg and MAavg are independent predictors of 3-month survival after MT of the ICA or M1-MCA. A 1-SD increase in MDavg and MAavg was associated with a 39%-43% decrease in the probability of death during the first 3 months after MT.

Predicting the degree of difficulty of the trans-radial approach in cerebral angiography.

BACKGROUND: To evaluate anatomical and clinical factors that make trans-radial cerebral angiography more difficult. METHODS: A total of 52 trans-radial diagnostic angiograms were evaluated in a tertiary care stroke center from December 2019 until March 2020. We analyzed a number of anatomical variables to evaluate for correlation to outcome measures of angiography difficulty. RESULTS: The presence of a proximal radial loop had a higher conversion to femoral access (p<0.03). The presence of a large diameter aortic arch (p<0.01), double subclavian innominate curve (p<0.01), left proximal common carotid artery (CCA) loop (p<0.001), acute subclavian vertebral angle (p<0.01), and absence of bovine aortic arch anatomy (p=0.03) were associated with more difficult trans-radial cerebral angiography and increased fluoroscopy time-per-vessel. CONCLUSION: The presence of a proximal radial loop, large diameter aortic arch, double subclavian innominate curve, proximal left CCA loop, acute subclavian vertebral angle, and absence of bovine aortic arch anatomy were associated with more difficult trans-radial cerebral angiography. We also introduce a novel grading scale for diagnostic trans-radial angiography.

Stent-assisted coiling of cerebral aneurysms: multi-center analysis of radiographic and clinical outcomes in 659 patients.

INTRODUCTION: The endovascular stent-assisted coiling approach for the treatment of cerebral aneurysms is evolving rapidly with the availability of new stent devices. It remains unknown how each type of stent affects the safety and efficacy of the stent-coiling procedure. METHODS: This study compared the outcomes of endovascular coiling of cerebral aneurysms using Neuroform (NEU), Enterprise (EP), and Low-profile Visualized Intraluminal Support (LVIS) stents. Patient characteristics, treatment details and angiographic results using the Raymond-Roy grade scale (RRGS), and procedural complications were analyzed in our study. RESULTS: Our study included 659 patients with 670 cerebral aneurysms treated with stent-assisted coiling (NEU, n=182; EP, n=158; LVIS, n=330) that were retrospectively collected from six academic centers. Patient characteristics included mean age 56.3±12.1 years old, female prevalence 73.9%, and aneurysm rupture on initial presentation of 18.8%. We found differences in complete occlusion on baseline imaging, defined as RRGS I, among the three stents: LVIS 64.4%, 210/326; NEU 56.2%, 95/169; EP 47.6%, 68/143; P=0.008. The difference of complete occlusion on 10.5 months (mean) and 8 months (median) angiographic follow-up remained significant: LVIS 84%, 251/299; NEU 78%, 117/150; EP 67%, 83/123; P=0.004. There were 7% (47/670) intra-procedural complications and 11.5% (73/632) post-procedural-related complications in our cohort. Furthermore, procedure-related complications were higher in the braided-stents vs laser-cut, P=0.002. CONCLUSIONS: There was a great variability in techniques and choice of stent type for stent-assisted coiling among the participating centers. The type of stent was associated with immediate and long-term angiographic outcomes. Randomized prospective trials comparing the different types of stents are warranted.

The Longest Angiographic and Clinical Follow-Up of Microsurgically Treated Giant Intracranial Aneurysms: Experience with 70 Cases.

BACKGROUND: Giant intracranial aneurysms (GIAs), if left untreated, have an extremely poor natural history. Despite many reports about the surgical treatment of GIAs, their long-term clinical and angiographic results are unclear. To our knowledge, this study reports the longest clinical and angiographic follow-up of microsurgically treated GIAs in the English literature. METHODS: Between January 1997 and December 2017, 70 patients with giant anterior circulation aneurysms treated using microsurgery were retrospectively reviewed. The applied microsurgical techniques and especially long-term clinical and angiographic follow-up data were evaluated. RESULTS: The mean aneurysm size was 29.2 mm (range, 25-58 mm). The aneurysm neck was occluded in 61 patients (87.2%). Nine aneurysms were clipped using an aneurysm clip compression technique. In 8 patients (11.4%), the aneurysm neck was found smaller at surgery than expected according to angiographic findings. Postoperative angiograms showed complete occlusion in 52 of 61 patients (85.2%). The treatment results at discharge were excellent-good (modified Rankin Scale score ≤2) in 75.3% of the patients. The overall mortality was 7.6%. At long-term clinical follow-up (mean, 105.2 months), 48 patients (78.6%) showed excellent-good outcome. At late angiographic follow-up (mean, 98.0 months), no recurrence was seen in patients with complete aneurysm closure. CONCLUSIONS: Most giant anterior circulation aneurysms can be successfully clipped, with acceptable morbidity and mortality. Some giant aneurysms have a smaller neck than expected. The aneurysm clip compression technique is useful in clipping of GIAs. This longest clinical and angiographic follow-up in the literature shows that clip ligation has excellent durability in GIAs, also.

Impact of procedural time on clinical and angiographic outcomes in patients with acute ischemic stroke receiving endovascular treatment.

BACKGROUND: Procedural time in patients with acute ischemic stroke (AIS) undergoing mechanical thrombectomy may affect clinical outcomes. We performed a pooled analysis of the effect of procedural time on clinical outcomes using data from three prospective endovascular treatment trials. OBJECTIVE: To examine the relationship between endovascular procedural time and clinical outcomes of patients with AIS following endovascular treatment. METHODS: We analyzed data from SWIFT, STAR, and SWIFT PRIME studies, including baseline characteristics: National Institutes of Health Stroke Scale (NIHSS) score on admission, intracranial hemorrhage rates, and modified Rankin Scale score at 3 months. The Thrombolysis in Cerebral Infarction (TICI) scale was used to grade postprocedure recanalization. We recorded two procedural time intervals: (1) symptom onset to groin puncture and (2) groin puncture to angiographic recanalization. A multivariate analysis was performed using a logistic regression model to analyze predictors of unfavorable outcome. RESULTS: We analyzed 301 patients who had undergone endovascular treatment and had near-complete or complete recanalization (TICI 2b or 3). At 3 months, 122 patients (40.5%) had unfavorable outcomes. The rate of favorable outcomes was significantly higher when the procedural time was <60 min compared with ≥60 min (62% vs 45%, p=0.020). Predictors of unfavorable outcome at 3 months were age (unit 10 years, OR=0.62, 95% CI 0.46 to 0.82, p<0.001), onset to groin puncture time (unit hour, OR=0.61, 95% CI 0.48 to 0.77, p<0.001), groin puncture to recanalization (unit 10 min, OR=0.89, 95% CI 0.80 to 0.99, p=0.032), baseline NIHSS score (20-28 vs 8-10, OR=0.17, 95% CI 0.05 to 0.62, p=0.018), and collaterals (OR=1.48, 95% CI 1.04 to 2.10, p=0.029). CONCLUSION: Procedural time in patients with stroke undergoing mechanical thrombectomy may be an important determinant of favorable outcomes in those with recanalization.

Neuroform Atlas Stent System for the treatment of intracranial aneurysm: primary results of the Atlas Humanitarian Device Exemption cohort.

BACKGROUND AND OBJECTIVE: Stent-assisted coil embolization is a well-established treatment of intracranial wide-necked aneurysms. The Neuroform Atlas Stent System is a new generation microstent designed to enhance coil support, conformability, deliverability, and improve deployment accuracy. We present the 1-year efficacy and angiographic results of the Humanitarian Device Exemption (HDE) cohort from the Atlas Investigational Device Exemption (IDE) clinical trial. METHOD: The Atlas IDE trial is a prospective, multicenter, single-arm, open-label study of unruptured wide-necked intracranial aneurysms treated with the Neuroform Atlas stent and approved coils. The primary efficacy endpoint was the rate of 12-month complete aneurysm angiographic occlusion (Raymond class I) without target aneurysm retreatment or significant parent artery stenosis (>50%) at the target location. The primary safety endpoint was the rate of major ipsilateral stroke or neurological death within 12 months. Imaging core laboratory and Clinical EventsCommittee adjudicated the primary endpoints. RESULTS: 30 patients were enrolled at eight US centers, with 27 patients completing the 12-month angiographic follow-up. The mean age was 59.4±11.8 years and 24/30 patients (80%) were women. The mean aneurysm size was 5.3±1.7 mm and the dome:neck ratio was 1.1±0.2. Procedural technical success of Neuroform Atlas Stent deployment was 100%. 27 patients completed 12-month angiographic follow-up and 30 patients completed their 6-month follow-up. When applying the last observation carried forward method, the primary efficacy endpoint was observed in 26/30 patients (86.7%, 95% CI 69.3% to 96.2%) compared with 25/27 patients (92.6%, 95% CI 75.7% to 99.1%) who completed the 12-month angiographic follow-up. The primary safety endpoint of stroke occurred in one patient (3.3%), who made a complete clinical recovery at discharge. There were no neurological deaths. CONCLUSION: The Neuroform Atlas stent in conjunction with coils demonstrated a high rate of complete aneurysm occlusion at 12-month angiographic follow-up, with an improved safety profile in the HDE cohort. CLINICAL TRIALGOV REGISTRATION NUMBER: NCT0234058;Results.

Validation of an extrinsic compression and early ambulation protocol after diagnostic transfemoral cerebral angiography: a 5-year prospective series.

BACKGROUND AND PURPOSE: Access-site complications constitute a substantial portion of the morbidity associated with transfemoral cerebral angiography, yet no standardized protocol exists for femoral closure and practice patterns vary widely. The objective of this single-arm prospective cohort study was to validate the efficacy and safety of a standardized femoral closure strategy for all diagnostic angiography, regardless of antiplatelet regimen. METHODS: A single-arm, prospective study was designed enrolling consecutive patients undergoing diagnostic transfemoral cerebral angiography by a single neurointerventional surgeon from March 2013 - March 2018. The closure protocol consisted of 20 minutes of manual compression to the site of arterial access and 2 hours of bedrest. The primary outcome was hematoma or oozing after manual compression. Demographic, clinic, and laboratory data were collected and analyzed, and patients were stratified by antiplatelet use. RESULTS: Of 525 angiograms, 263 (50.1%) were on patients taking antiplatelet medication, with 66 (12.6%) on dual antiplatelet regimens. Five patients (0.95% of all patients) met the primary outcome: in all five cases, there was no further oozing or enlarging hematoma after the additional compression period. There were not significant differences in primary outcome in groups stratified by antiplatelet use, and there were no instances of delayed hematoma, pseudoaneurysm, or arteriovenous fistula. CONCLUSION: In this single-arm cohort study of 525 consecutive transfemoral angiograms with a standardized extrinsic compression protocol, hemostasis was achieved without complication in >99% regardless of antiplatelet strategy. This protocol is effective and safe for diagnostic transfemoral angiography regardless of a patient's antiplatelet use.

WEB embolization versus stent-assisted coiling: comparison of complication rates and angiographic outcomes.

BACKGROUND: Intrasaccular flow disruption represents a new paradigm in endovascular treatment of wide-necked bifurcation aneurysms. OBJECTIVE: To perform a matched case-control study comparing complications and angiographic outcome using the Woven Endobridge (WEB) device and stent-assisted coiling (SAC). METHODS: Sixty-six patients treated with the WEB at three German tertiary care centers were included and matched with 66 patients treated with SAC based on aneurysm location and unruptured/ruptured aneurysm status. Parameters were retrospectively analysed and compared between the treatment groups using inverse probability of treatment weighting (IPTW) with propensity scores. RESULTS: Procedural complication rates were 12.1% in the WEB group and 21.2% in the SAC group, which was statistically significant after IPTW adjustment (OR=2.2, 95% CI 1.08 to 4.4, p=0.03). Favourable outcome (modified Rankin scale score ≤2) was achieved by 57/66 (86.4%) in the WEB group and 57/66 (86.4%) in the SAC group (p=1.0). At mid-term follow-up, a similar number of aneurysms achieved adequate occlusion (complete occlusion or neck remnant) in the WEB group (93.9%) and in the SAC group (93.9%, p=1.0). Re-treatment was performed in 10.6% after WEB embolization and 12.1% after SAC (p=1.0). CONCLUSIONS: The WEB provides similar mid-term aneurysm occlusion rates to those of SAC, with no additional morbidity and potentially lower complication rates. Long-term outcome analysis will provide a definite conclusion on the use of WEB for intracranial aneurysms.

A clinical comparison of Atlas and LVIS Jr stent-assisted aneurysm coiling.

BACKGROUND: Case series have described the safety and efficacy of LVIS Jr and Atlas stent-assisted aneurysm coiling, but their comparative clinical performance has not yet been formally studied. OBJECTIVE: To clinically compare LVIS Jr and Atlas stents, emphasizing comparative rates of technical success and complications. METHODS: Our institutional endovascular database was queried for aneurysms treated by stent-assisted coiling with either the LVIS Jr or Atlas stents. Demographic data, aneurysm information, treatment technique, periprocedural and device-related complications, and initial and follow-up angiographic results were evaluated. RESULTS: Thirty-seven patients underwent Atlas stent placement and 27 patients underwent LVIS Jr stent placement for aneurysm coiling. There was no significant difference in aneurysm location, size, coiling technique, and coil packing density between the two cohorts. The rate of initial Raymond 1 occlusion was significantly greater in the Atlas cohort (57% vs 41%, P=0.03). The rate of postoperative ischemic complications, both clinically apparent and as defined on postoperative MRI diffusion-weighted imaging, did not significantly differ between the two groups. Follow-up DSA demonstrated a significantly greater rate of Raymond 1 or 2 occlusion for the Atlas cohort (100% vs 81%, P=0.04), and a significantly lower rate of in-stent stenosis (0% vs 19%, P=0.04). CONCLUSION: This institutional analysis demonstrates greater obliteration rates and lower in-stent stenosis rates for aneurysms treated via Atlas stent-assisted coiling as compared with those treated via LVIS Jr stent-assisted coiling.

Treatment strategies for recurrent and residual aneurysms after Woven Endobridge implantation.

BACKGROUND: Woven 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 to date. We present our multicenter experience of endovascular retreatment of aneurysm recurrence after WEB implantation. METHODS: This is a multicenter study of patients who underwent endovascular retreatment after WEB implantation in three German tertiary care centers. Treatment strategies, complications, and angiographic outcome were retrospectively assessed. RESULTS: Among 122 aneurysms treated with the WEB device, 15 were retreated. Of these, six were initially treated with the WEB only, two were pretreated by coiling, and seven large aneurysms were treated in a multimodality approach. Ten were true aneurysm remnants and five were neck remnants. The reasons for retreatment were WEB migration (n=6), initial incomplete occlusion (n=5), and WEB compression (n=4). Retreatment strategies included coiling (n=4), stent-assisted coiling (n=7), flow diversion (n=3), and placement of an additional WEB (n=1). All procedures were technically successful and there were no procedure-related complications. Among 11 patients available for follow-up after retreatment, three were retreated again. At last angiographic follow-up, available in 11/15 cases at a median of 23 months, complete occlusion was obtained in eight cases and neck remnants in three. CONCLUSIONS: This pilot study shows that endovascular retreatment of recurrent or residual aneurysms after WEB implantation can be done safely and can achieve adequate occlusion rates.

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.

A Meta-Analysis of Risk Factors for the Formation of de novo Intracranial Aneurysms.

BACKGROUND: Understanding the risk factors for the formation of de novo intracranial aneurysms (IAs) is important for patients who have ever suffered a cerebral aneurysm. OBJECTIVE: To estimate the risk factors for the development of a de novo IA to identify which patients need more aggressive surveillance after aneurysm treatment. METHODS: We followed the preferred reporting items for systematic reviews and meta-analyses guidelines and searched the PubMed, CENTRAL, EMBASE, and LILACS databases using the key words cerebral aneurysms, de novo, IAs, risk factors combined using and/or. The search was performed in July 2017.We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using RevMan 5.3 (Cochrane, London, United Kingdom) to evaluate risk factors. Statistical significance was set at P < .05. RESULTS: The analysis included 14 studies involving 6389 patients, of whom 197 patients had de novo IAs. The main risk factors for formation included sex (OR = 1.82, 95% CI [1.30,2.56], P = .0005, female vs male), age <40 yr (OR = 2.96, 95% CI [1.76,4.96], P < .0001), family history (OR = 2.05, 95% CI [1.07,3.93], P = .03), smoking history (OR = 2.73, 95% CI [1.81,4.12], P < .0001), and multiple saccular intracranial aneurysms (sIAs) at first diagnosis (OR = 2.10, 95% CI [1.12,3.91], P = .02), internal carotid artery (ICA) as the initial site (OR = 2.58, 95% CI [1.43,4.68], P = .002). Heterogeneous analysis showed that these I2 were less than 50% and the results were reliable. CONCLUSION: Observational evidence identified multiple clinical and anatomic risk factors for the formation of de novo IAs, including female sex, age <40 yr, family history, smoking history, multiple sIAs at first diagnosis, and IC as the initial site. More aggressive long-term angiographic follow-up with digital subtraction angiography, computed tomography angiography, or magnetic resonance angiography is recommended for these patients.

A new method to statistically describe microcatheter tip position in patient-specific aneurysm models.

BACKGROUND AND PURPOSE: Evidence on how to select microcatheters to facilitate aneurysm catheterization during coil embolization is sparse. We developed a new method to define microcatheter tip location inside a patient-specific aneurysm model as a 3-dimensional probability map. We hypothesized that precision and accuracy of microcatheter tip positioning depend on catheter tip shape and aneurysmal geometry. MATERIALS AND METHODS: Under fluoroscopic guidance two to three operators introduced differently shaped microcatheters (straight, 45°, 90°) into eight aneurysm models targeting the anatomic center of the aneurysm. Each microcatheter position was recorded with flat-panel CT, and 3-dimensional probability maps of the microcatheter tip positions were generated. Maps were assessed with histogram analyses and compared between tip shapes, aneurysm locations and operators. RESULTS: Among a total of 530 microcatheter insertions, the precision (mean distance between catheter positions) and accuracy (mean distance to target position) were significantly higher for the 45° tip (1.10±0.64 mm, 3.81±1.41 mm, respectively) than for the 90° tip (1.27±0.57 mm, p=0.010; 4.21±1.60 mm p=0.014, respectively). Accuracy was significantly higher in posterior communicating artery aneurysms (3.38±1.20 mm) than in aneurysms of the internal carotid artery (4.56±1.54 mm, p<0.001). CONCLUSION: Our method can be used tostatistically describe statistically microcatheter behavior in patient-specific anatomy, which may improve the available evidence guiding microcatheter shape selection. Experience increases the ability to reach the intended position with a microcatheter (accuracy) that is also dependent on the aneurysm location, whereas catheter tip choice determines the variability of catheter tip placements versus each other (precision). Clinical validation is required.

Selective compromise of hypoplastic posterior communicating artery variants with aneurysms treatable by coil embolization: clinical and radiologic outcomes.

BACKGROUND: Posterior communicating artery (PcoA) compromise may serve as adjunctive treatment in patients with hypoplastic variants of PcoA who undergo coil embolization of PcoA aneurysms. However, procedural safety and the propensity for later recanalization are still unclear. OBJECTIVE: To evaluate clinical and radiologic outcomes of coil embolization in this setting, focusing on compromise of PcoA. METHODS: As a retrospective review, we examined 250 patients harboring 291 aneurysms of hypoplastic PcoAs, all consecutively treated by coil embolization between January 2004 and June 2016. PcoA compromise was undertaken in conjunction with 81 of the treated aneurysms (27.8%; incomplete 53; complete 28). Medical records and radiologic data were assessed during extended monitoring. RESULTS: During the mean follow-up of 33.9±24.6 months (median 36 months), a total of 107 (36.8%) coiled aneurysms showed recanalization (minor 50; major 57). Recanalization rates were as follows: PcoA preservation 40.5% (85/210); incomplete PcoA occlusion 34.0% (18/53); complete PcoA occlusion 14.3% (4/28). Aneurysms >7 mm (HR 3.40; P<0.01), retreatment for recanalization (HR 3.23; P<0.01), and compromise of PcoA (P<0.01) emerged from multivariate analysis as significant risk factors for recanalization. Compared with PcoA preservation, complete PcoA compromise conferred more favorable outcomes (HR 0.160), whereas incomplete compromise of PcoA fell short of statistical significance. Thromboembolic infarction related to PcoA compromise did not occur in any patient. CONCLUSION: PcoA compromise in conjunction with coil embolization of PcoA aneurysms appears safe in hypoplastic variants of PcoA, helping to prevent recanalization if complete occlusion is achieved.

Transient in-stent stenosis at mid-term angiographic follow-up in patients treated with SILK flow diverter stents: incidence, clinical significance and long-term follow-up.

BACKGROUND: Little is known about in-stent stenosis (ISS) in patients with aneurysms treated with flow diverter (FD) stents. The reported incidence in the literature varies significantly. OBJECTIVE: The aim of this study was to assess the incidence, severity, distribution, clinical significance, and possible predictors for ISS. METHODS: Between July 2012 and June 2016 we retrospectively reviewed all patients treated with SILK FDs in our center. Only cases with short-term (4±2 months) and long-term (>1 year) follow-ups with digital subtraction angiograms were included. ISS was graded as mild (<25%), moderate (25-50%) or severe (>50%). The following predictors for ISS were assessed: gender, age, the presence of subarachnoid hemorrhage, aneurysm size, location, occlusion status, and post-stenting angioplasty. RESULTS: Thirty-six patients met the inclusion criteria. At mid-term follow-up, ISS was observed in 16/36 patients (44%). Eleven patients (69%) had mild ISS, three (19%) moderate, and two (12%) severe ISS. ISS was diffuse in 11 patients (69%) and focal in five patients (31%). All patients were asymptomatic. Thirteen patients were maintained on dual antiplatelet therapy and three on aspirin alone. At long-term follow-up, complete ISS resolution was seen in 11 patients, improvement in three and worsening in two patients. No de novo ISS occurrence was observed. On univariate analysis there was no significant predictor for ISS. CONCLUSIONS: Transient ISS after FD deployment is a common asymptomatic finding on mid-term angiographic follow-up. Complete resolution or improvement at long-term follow-up is seen in most patients who are maintained on dual antiplatelet therapy.

Treatment of intracranial aneurysms using the pipeline flex embolization device with shield technology: angiographic and safety outcomes at 1-year follow-up.

PURPOSE: The Pipeline Embolization Device (PED) is a routine first-line treatment option for intracranial aneurysms (IAs). The Pipeline Flex Embolization Device with Shield Technology (Pipeline Shield) is an updated version of the PED which has been modified to include a surface phosphorylcholine biocompatible polymer. Its early technical success and safety have been reported previously. Here, we assessed the long-term safety and efficacy of the Pipeline Shield for the treatment of IAs. MATERIALS AND METHODS: The Pipeline Flex Embolization Device with Shield Technology (PFLEX) study was a prospective, single-arm, multicenter study for the treatment of unruptured IAs using the Pipeline Shield. The primary endpoint was a major stroke in the territory supplied by the treated artery or neurologic death at 1-year post-procedure. Angiographic outcomes were also assessed by an independent radiology laboratory at 6 months and 1 year. RESULTS: Fifty patients (mean age, 53 years; 82% female) with 50 unruptured IAs were treated. Mean aneurysm diameter was 8.82±6.15 mm. Of the target aneurysms, 38/50 (76%) were small (<10 mm), 11/50 (22%) were large (≥10 and<25 mm), and 1/50 (2%) was giant (≥25 mm). Forty-seven (94%) were located in the internal carotid artery and three (6%) in the vertebral artery. At 1-year post-procedure, no major strokes or neurologic deaths were reported, and complete occlusion was achieved in 27/33 (81.8%). There were no instances of aneurysm recurrence or retreatment. CONCLUSIONS: Our 1-year follow-up concerning angiographic and safety outcomes corroborate previous evidence that the Pipeline Shield is a safe and effective treatment for IAs. TRIAL REGISTRATION NUMBER: NCT02390037.

Transient in-stent stenosis: a common finding after flow diverter implantation.

BACKGROUND AND PURPOSE: In recent years, implantation of flow diverters has emerged as an option for the endovascular treatment of intracranial aneurysms. One complication of treatment with flow diverters is the occurrence of in-stent stenosis, which has been reported to be partially reversible. The purpose of our study was to assess the incidence and dynamics of in-stent stenosis on angiographic short term and long term follow-up after treatment with flow diverters. METHODS: A retrospective review of our prospectively maintained database identified all patients with intracranial internal carotid artery (ICA) aneurysms treated by flow diverters at our institution between 2014 and 2017. Clinical charts, procedural data, and angiographic results were reviewed. RESULTS: 18 patients were included. The mean short term follow-up was 92±19 days and mean long term follow-up was 449±120 days after treatment. No neurologic complications were observed. There was no procedure related mortality. Long term angiographic results showed complete occlusion in 83.3%, neck remnants in 11.1%, and incomplete occlusion in 5.5% of cases. In-stent stenosis was observed in all cases. Mean stenosis improved significantly from 30% on short term follow-up to 12% on long-term follow-up (P<0.0001). CONCLUSION: In-stent stenosis is a common finding on short term follow-up after the treatment with flow diverters but improves over time.

The occurrence of neointimal hyperplasia after flow-diverter implantation is associated with cardiovascular risks factors and the stent design.

BACKGROUND: Neo-intimal hyperplasia (NIH) is frequently observed after flow-diverter stent (FDS) implantation. Although mostly asymptomatic, this vascular response can sometimes lead to delayed ischemic strokes. This study intended to evaluate the factors potentially influencing the rates of NIH following FDS treatment. MATERIAL AND METHODS: All aneurysm treatments performed with a Pipeline embolization device (PED) or a SILK stent from May 2011 to May 2015 were collected in a prospectively maintained database. Patient demographics, clinical, and angiographic outcomes including both digital subtraction angiography and C-arm cone-beam CT were registered. Two blind reviewers rated the presence of NIH on a binary scale (present/absent). RESULTS: From 148 patients, 63 datasets were available for analysis. Inter-reader agreement was excellent (Kappa=0.88). NIH was positively correlated with smoking, dyslipidemia, and high blood pressure, but not with aneurysm characteristics. At early follow-up (<12 months), NIH was more frequently associated with the use of the SILK stent (68%) rather than the PED (38%): P<0.02. At long-term follow-up, the NIH rate in the total population dropped from 55% to 26% with no more significant difference between the two stents. The complete occlusion rate as seen in early follow-up was higher in the SILK group with 76% vs 65% but without statistical significance (P=0.4). CONCLUSION: NIH is a dual-vessel reaction after FDS implant. When planning a treatment in locations at risk of ischemic complications if severe NIH would occur, then the stent design should be considered. However, minimal NIH might also be needed as it is involved in aneurysm healing. Before treatment patients should be recommended best medical management of their cardiovascular risks factors to prevent an excessive NIH reaction.

Causes of early rebleeding after coil embolization of ruptured cerebral aneurysms.

OBJECTIVE: Early rebleeding after coil embolization of a ruptured cerebral aneurysm is rare but may cause severe disability or death. We present a case series of early rebleeding after coil embolization of ruptured cerebral aneurysms and investigate the incidence, clinical outcome and possible mechanism through retrospective analysis of angiographic and surgical findings. PATIENTS AND METHODS: This study included 347 consecutive patients who had undergone successful coil embolization of 347 ruptured cerebral saccular aneurysms. Clinical and angiographic data and findings from emergent surgery were analyzed retrospectively. RESULTS: Early rebleeding occurred in eight aneurysms (2.3%) and was especially frequent among anterior communicating artery lesions (6 out of 122, 4.9%). The other two events involved posterior communication artery lesions. The maximum diameter of the aneurysms that developed early rebleeding was 4.89 ± 0.65 mm, ranging from 3.9 to 5.7 mm. In seven out of eight patients, the immediate radiologically determined occlusion status was a residual neck, and the remaining patient had a residual sac. The coil packing density was between 21% and 34%. Six cases of rebleeding were detected within 48 h, 1 case was detected on the 5th day, and 1 case was detected on the 10th day. Coil compaction was not detected by follow-up angiography after early rebleeding. We performed surgical clipping as a rescue procedure in 5 cases and additional coil embolization in 1 case. During follow-up angiography and rescue clipping, inflow of blood to the aneurysm was detected in 6 cases. Three patients died, and the other 3 patients were severely disabled. The mechanisms of early rebleeding were divided into two types. First, blood may flow into the rupture site through a gap between the coil mesh and the aneurysm neck. Second, blood may enter the rupture site through the coil mesh due to insufficient thrombus formation. CONCLUSIONS: The early rebleeding rate after coil embolization of ruptured cerebral aneurysms in our study was 2.3%. The ruptured aneurysms were small in size (<6 mm), and rupture frequently occurred in the anterior communicating artery. In most cases, inflow of blood to the aneurysm was detected by follow-up angiography or during rescue surgery.