Angiographic and clinical outcomes from 396 aneurysms treated with the pipeline flex embolization device with shield technology.

BACKGROUND: The PEDESTRIAN registry demonstrated high rates of complete long-term occlusion and good clinical outcomes among patients with intracranial aneurysms treated with the pipeline embolization device. The pipeline flex embolization device with shield technology was introduced to minimize thromboembolic complications. In this study, we investigated the safety and effectiveness of pipeline embolization device with shield technology among all patients treated for intracranial aneurysms at our center. METHODS: This was a single-arm retrospective study of prospectively collected data of patients treated with pipeline embolization device with shield technology at our high-volume center between January 2018-January 2021. The primary efficacy endpoint was complete occlusion as measured by a class 1 Raymond-Roy score at 1-year and 2-year follow-up. The primary safety endpoint was major morbidity and neurological mortality up to 1 year following intervention. RESULTS: A total of 328 patients (mean age 56.1 ± 14.7 years; 81.1% female), 80 of whom were previously included in PEDESTRIAN, with 396 aneurysms, were analyzed. A total of 378 devices were deployed, with 93.9% (372/396) of aneurysms requiring only one device. Follow-up angiography was available for 90.2% (296/328) of the procedures after a mean time of 14.0 ± 8.2 months. Complete occlusion was demonstrated for 78.5% (132/168) of aneurysms at 12 months and 90.7% (98/108) at 24 months. The overall rates of major morbidity and neurological mortality after 2 years were 1.5% (5/328) and 0.6% (2/328), respectively. CONCLUSION: Our results demonstrate high rates of complete long-term occlusion among patients treated with pipeline embolization device with shield technology. We also observed low rates of mortality and morbidity consistent with fewer thromboembolic complications with pipeline embolization devices with shield technology.

Impacto de la inteligencia artificial en las métricas terapéuticas del ataque cerebrovascular durante la pandemia COVID-19 / Impact of artificial intelligence on therapeutic metrics of cerebrovascular attack during the COVID-19 pandemic

Resumen Introducción : El inicio de la pandemia COVID-19, obligó a implementar cambios en el sistema de aten ción de los servicios de emergencia. Coincidentemente, en nuestra institución, implementamos el software de inteligencia artificial (IA), RAPID.AI, para el análisis de imágenes en el ataque cerebrovascular isquémico (ACVi). Nuestro objetivo fue evaluar el impacto del uso de la IA junto a los cambios en el triage durante la pandemia por COVID-19 en pacientes con ACVi por oclusión de gran vaso cerebral (OGVC). Métodos : Se crearon 2 grupos de pacientes con ACVi por OGVC tratados con terapia de reperfusión endovenosa más endovascular o terapia endovascu lar directa. Grupo 1: pacientes de enero 2019 a junio 2020; Grupo 2: pacientes de julio 2020 a diciembre de 2021, estudiados con RAPID.AI. Se analizaron datos clínicos, y métricas temporales. Se compararon según hora de arribo de 08:00 a 20:00 h (diurno) vs. 20:01 a 7:59 h (nocturno). Resultados : El grupo 1 comprendió 153 pacientes y el grupo 2 133. En el grupo 2 la métrica puerta-imagen y adquisición de la imagen fueron menores, con menor tiempo puerta-inicio de imagen y puerta-recanalización; los pacientes en horario nocturno presentaron mayor NIHSS y tiempos inicio-ingreso con menor proporción de independencia funcional a 90 días. Conclusiones : El uso de la IA para el análisis de imá genes junto a un menor tiempo puerta-fin de imagen, permitió acortar el intervalo hasta la punción inguinal. En el análisis por horarios durante la pandemia, los pacientes ingresados en horario diurno presentaron métricas puerta-imagen, tiempo de imagen y puerta-recanalización significativamente menores.

Abstract Introduction : The start of the COVID-19 pandemic forced the implementation of changes in the emergency services care system. Concomitantly, at our institution, we implemented the artificial intelligence (AI) software, RAPID.AI, for image analysis in ischemic stroke (IS). Our objective was to evaluate the impact of the use of AI together with the changes in the triage during the COVID-19 pandemic in patients with stroke due to large vessel occlusion (LVO). Methods : We included patients with IS due to LVO treated with intravenous reperfusion therapy plus en dovascular or direct endovascular therapy. Results : Two groups were created. Group 1: patients from January 2019 to June 2020; Group 2: patients from July 2020 to December 2021, studied with RAPID.AI. Clini cal data and temporal metrics were analyzed. They were compared according to arrival time from 08:00 to 20:00 (daytime) vs 20:01 to 7:59 (night). Results: We included 286 patients, 153 in group 1 and 133 in group 2. In group 2, door-image metric and image duration were lower, with shorter door-image onset and door-recanalization times; patients who arrived at night had higher NIHSS and longer time from onset-to-door with lower propor tion of functional independence at 90 days (mRS ≤ 2). Conclusions : The use of AI for image analysis along with a shorter door to end of image time allowed to reduce the interval to groin puncture. In the analysis by hours during the pandemic, patients admitted in daytime hours had significantly lower door to image, image time acquisition, and door to recanalization metrics.

[Impact of artificial intelligence on therapeutic metrics of cerebrovascular attack during the COVID-19 pandemic]. / Impacto de la inteligencia artificial en las métricas terapéuticas del ataque cerebrovascular durante la pandemia COVID-19.

INTRODUCTION: The start of the COVID-19 pandemic forced the implementation of changes in the emergency services care system. Concomitantly, at our institution, we implemented the artificial intelligence (AI) software, RAPID.AI, for image analysis in ischemic stroke (IS). Our objective was to evaluate the impact of the use of AI together with the changes in the triage during the COVID-19 pandemic in patients with stroke due to large vessel occlusion (LVO). METHODS: We included patients with IS due to LVO treated with intravenous reperfusion therapy plus endovascular or direct endovascular therapy. RESULTS: Two groups were created. Group 1: patients from January 2019 to June 2020; Group 2: patients from July 2020 to December 2021, studied with RAPID.AI. Clinical data and temporal metrics were analyzed. They were compared according to arrival time from 08:00 to 20:00 (daytime) vs 20:01 to 7:59 (night). RESULTS: We included 286 patients, 153 in group 1 and 133 in group 2. In group 2, door-image metric and image duration were lower, with shorter door-image onset and door-recanalization times; patients who arrived at night had higher NIHSS and longer time from onset-to-door with lower proportion of functional independence at 90 days (mRS = 2). CONCLUSIONS: The use of AI for image analysis along with a shorter door to end of image time allowed to reduce the interval to groin puncture. In the analysis by hours during the pandemic, patients admitted in daytime hours had significantly lower door to image, image time acquisition, and door to recanalization metrics.

Introducción: El inicio de la pandemia COVID-19, obligó a implementar cambios en el sistema de atención de los servicios de emergencia. Coincidentemente, en nuestra institución, implementamos el software de inteligencia artificial (IA), RAPID.AI, para el análisis de imágenes en el ataque cerebrovascular isquémico (ACVi). Nuestro objetivo fue evaluar el impacto del uso de la IA junto a los cambios en el triage durante la pandemia por COVID-19 en pacientes con ACVi por oclusión de gran vaso cerebral (OGVC). Métodos: Se crearon 2 grupos de pacientes con ACVi por OGVC tratados con terapia de reperfusión endovenosa más endovascular o terapia endovascular directa. Grupo 1: pacientes de enero 2019 a junio 2020; Grupo 2: pacientes de julio 2020 a diciembre de 2021, estudiados con RAPID.AI. Se analizaron datos clínicos, y métricas temporales. Se compararon según hora de arribo de 08:00 a 20:00 h (diurno) vs. 20:01 a 7:59 h (nocturno). Resultados: El grupo 1 comprendió 153 pacientes y el grupo 2 133. En el grupo 2 la métrica puerta-imagen y adquisición de la imagen fueron menores, con menor tiempo puerta-inicio de imagen y puerta-recanalización; los pacientes en horario nocturno presentaron mayor NIHSS y tiempos inicio-ingreso con menor proporción de independencia funcional a 90 días. Conclusiones: El uso de la IA para el análisis de imágenes junto a un menor tiempo puerta-fin de imagen, permitió acortar el intervalo hasta la punción inguinal. En el análisis por horarios durante la pandemia, los pacientes ingresados en horario diurno presentaron métricas puerta-imagen, tiempo de imagen y puertarecanalización significativamente menores.

Results of the pToWin Study: Using the pCONUS Device for the Treatment of Wide-Neck Intracranial Aneurysms.

Coil embolization has become a well-established option for the treatment of intracranial aneurysms. Yet, wide-neck bifurcation aneurysms (WNBAs) remain a challenge. The pCONUS is the first generation of a stent-like implant for the bridging of WNBAs to enable coiling. The pToWin study was a prospective, single-arm, multicenter study conducted to analyze the safety and efficacy of the pCONUS in the treatment of WNBAs. The primary effectiveness endpoint was the rate of adequate occlusion of the aneurysm at 3-6 and 7-12 months. The primary safety endpoint was the occurrence of major ipsilateral stroke or neurological death during the follow-up. A total of 115 patients were included. Aneurysm locations were the middle cerebral artery in 52 (45.2%), the anterior communicating artery in 35 (30.4%), the basilar artery in 23 (20%), the internal carotid artery terminus in three (2.6%), and the pericallosal artery in two (1.7%) patients. Treatment was successfully performed in all but one patient. The morbi-mortality rate was 1.9% and 2.3% at 3-6 and 7-12 months, respectively. Of the aneurysms, 75.0% and 65.6% showed adequate occlusion at 3-6 and 7-12 months, respectively. pCONUS offers a safe and reasonably effective treatment of WNBAs, demonstrated by acceptable adequate aneurysm occlusion and low rates of adverse neurologic events.

Ophthalmic artery angioplasty for age-related macular degeneration.

BACKGROUND: There is considerable overlap of contributors to cardiovascular disease and the development of age-related macular degeneration (AMD). Compromised ocular microcirculation due to aging and vascular disease contribute to retinal dysfunction and vision loss. Decreased choroidal perfusion is evident in eyes with dry AMD and is thought to play a role in retinal pigment epithelial dysfunction, the rate of development of geographic atrophy, and the development of neovascularization. The aim of the study was to demonstrate that AMD is correlated with a compromised blood flow in the ocular pathway and show OA angioplasty as a potential treatment of late-stage AMD. METHODS: Based on the potential for the ophthalmic artery (OA) to be an anatomical target for the treatment of AMD as outlined above, five patients were found to be eligible for compassionate use treatment, presenting clinically significant late-stage AMD with profound vision loss in one or both eyes, and are included in this retrospective study. RESULTS: OA narrowing, or significant calcium burden at the ophthalmic segment of the internal carotid artery compromising the origin of the OA was confirmed in all cases. Subsequent OA cannulation was achieved in all patients with some difficulty. Subjective patient reports indicated that all patients perceived a benefit following the procedure; however, improved postoperative visual acuity did not confirm that perceived benefit for one of the patients. CONCLUSIONS: Feasibility and safety of the OA angioplasty were demonstrated, and a benefit perceived in five patients with profound vision loss and a desire to achieve improved quality of life. A clinical trial with controlled schedule, imaging, and methodologies is needed to confirm these results.

Diversion-p64: results from an international, prospective, multicenter, single-arm post-market study to assess the safety and effectiveness of the p64 flow modulation device.

BACKGROUND: The use of flow diversion to treat intracranial aneurysms has increased in recent years. OBJECTIVE: To assess the safety and angiographic efficacy of the p64 flow modulation device. METHODS: Diversion-p64 is an international, prospective, multicenter, single-arm, study conducted at 26 centers. The p64 flow modulation device was used to treat anterior circulation aneurysms between December 2015 and January 2019. The primary safety endpoint was the incidence of major stroke or neurologic death at 3-6 months, with the primary efficacy endpoint being complete aneurysm occlusion (Raymond-Roy Occlusion Classification 1) on follow-up angiography. RESULTS: A total of 420 patients met the eligibility criteria and underwent treatment with the p64 flow modulation device (mean age 55±12.0 years, 86.2% female). Mean aneurysm dome width was 6.99±5.28 mm and neck width 4.47±2.28 mm. Mean number of devices implanted per patient was 1.06±0.47, with adjunctive coiling performed in 14.0% of the cases. At the second angiographic follow-up (mean 375±73 days), available for 343 patients (81.7%), complete aneurysm occlusion was seen in 287 (83.7%) patients. Safety data were available for 413 patients (98.3%) at the first follow-up (mean 145±43 days) with a composite morbidity/mortality rate of 2.42% (n=10). CONCLUSIONS: Diversion-p64 is the largest prospective study using the p64 flow modulation device. The results of this study demonstrate that the device has a high efficacy and carries a low rate of mortality and permanent morbidity.

First-in-human endovascular treatment of hydrocephalus with a miniature biomimetic transdural shunt.

Surgical ventriculoperitoneal shunting remains standard treatment for communicating hydrocephalus, despite persistently elevated infection and revision rates. A novel minimally invasive endovascular cerebrospinal fluid (CSF) shunt was developed to mimic the function of the arachnoid granulation which passively filters CSF from the central nervous system back into the intracranial venous sinus network. The endovascular shunt is deployed via a femoral transvenous approach across the dura mater into the cerebellopontine angle cistern. An octogenarian with intractable hydrocephalus following subarachnoid hemorrhage underwent successful endovascular shunting, resulting in swift intracranial pressure reduction from 38 to <20 cmH2O (<90 min) and resolution of ventriculomegaly. This first successful development of a percutaneous transluminal venous access to the central nervous system offers a new pathway for non-invasive treatment of hydrocephalus and the potential for intervention against neurological disorders.

Pipeline Embolization Devices for the Treatment of Intracranial Aneurysms, Single-Center Registry: Long-Term Angiographic and Clinical Outcomes from 1000 Aneurysms.

BACKGROUND: Prospective studies have established the safety and efficacy of the PipelineTM Embolization Device (PED; Medtronic) for treatment of intracranial aneurysms (IA). OBJECTIVE: To investigate long-term outcomes from the Pipeline Embolization Devices for the Treatment of Intracranial Aneurysms (PEDESTRIAN) Registry. METHODS: The PEDESTRIAN Registry data were retrospectively reviewed, which included patients (March 2006 to July 2019) with complex IAs treated with PED. Patients with unfavorable anatomy and/or recurrence following previous treatment were included and excluded those with acute subarachnoid hemorrhage. The primary angiographic endpoint was complete occlusion and long-term stability. Clinical and radiological follow-up was performed at 3 to 6 mo, 12 mo, and yearly thereafter. RESULTS: A total of 835 patients (mean age 55.9 ± 14.7 yr; 80.0% female) with 1000 aneurysms were included. Aneurysms varied in size: 64.6% were small (≤10 mm), 25.6% were large (11-24 mm), and 9.8% were giant (≥25 mm). A total of 1214 PEDs were deployed. Follow-up angiography was available for 85.1% of patients with 776 aneurysms at 24.6 ± 25.0 mo (mean). Complete occlusion was demonstrated in 75.8% of aneurysms at 12 mo, 92.9% at 2 to 4 yr, and 96.4% at >5 yr. During the postprocedural period, modified Rankin Scale scores remained stable or improved in 96.2% of patients, with stability or improvement in 99.1% of patients >5 yr. The overall major morbidity and neurological mortality rate was 5.8%. CONCLUSION: This study demonstrated high rates of long-term complete aneurysm occlusion, stable or improved functional outcomes, and low rates of complications and mortality. Clinical and angiographic outcomes improved over long-term follow-up, demonstrating that endovascular treatment of IA with PED is safe and effective.

Early Triage of Cardioembolic Sources Using Chest Spectral Computed Tomography in Acute Ischemic Stroke.

OBJECTIVES: The present study investigated the potential usefulness of delayed-phase, low-dose, non-gated, chest spectral CT scans (DSCT) for the early triage of cardioembolic (CE) sources in patients admitted with acute ischemic stroke (AIS), and for the simultaneous detection of myocardial disease and thrombotic complications. MATERIAL AND METHODS: Since July 2020 and promoted by the COVID-19 pandemic, we implemented the use of DSCT after cerebrovascular CT angiography (CTA) among patients with AIS using a dual-layer spectral CT. We explored the presence of CE sources, as well as late myocardium iodine enhancement (LIE) and pulmonary thromboembolism. Among patients further undergoing transesophageal echocardiogram (TEE) or cardiac CTA, we explored the diagnostic performance. RESULTS: Fifty consecutive patients with AIS who underwent DSCT after cerebrovascular CTA comprised the patient population. The confidence degree for excluding cardiac thrombi was significantly higher than for LIE (4.4±0.8 vs. 3.4±1.3, p<0.0001). DSCT identified a CE source in 4 (8%) and LIE in 24 (48%) patients. The iodine ratio of CE sources was significantly lower compared to the left atrial appendage of patients with no CE sources (0.25±0.1 mg/mL vs. 0.91±0.2 mg/mL, p<0.0001). TEE/cardiac CT, performed in 20 (40%) patients, identified a CE source in 5 (25%) cases, whereas DSCT identified 4 (20%), leading to a sensitivity and specificity of 80% (95% CI 28-99%) and 100% (95% CI 78-100%) respectively (kappa 0.86). CONCLUSIONS: In this pilot study, we identified DSCT as a potential unsophisticated approach for the early triage of CE sources among patients with AIS undergoing CTA upon admission.

Utilidad de la TC espectral cardíaca para la evaluación de complicaciones trombóticas en pacientes con ataque cerebrovascular isquémico / Usefulness of Spectral Cardiac Computed Tomography for the Evaluation of Thrombotic Complications in Patients with Ischemic Stroke

RESUMEN Objetivo: Evaluar la utilidad de la angiotomografía computada (TC) espectral cardíaca en pacientes con ataque cerebrovascular isquémico (ACVi). Material y métodos: En el contexto de pandemia de COVID-19 incorporamos la utilización de la TC espectral cardíaca en pacientes con ACVi para descartar en una única sesión, tanto fuentes cardioembólicas (FCE) como la presencia de complicaciones trombóticas o daño miocárdico. A partir de julio de 2020 incorporamos una adquisición tardía a las TC cardíacas en contexto de ACVi. Se presentan cuatro casos representativos sobre su utilidad y hallazgos cardiovasculares. Resultados: Se presentan cuatro casos registrados en un lapso de 40 días. Dos pacientes con FCE (aorta y orejuela izquierda) y dos con ACVi de origen indeterminado donde se evidenció miocardiopatía (isquémica y no isquémica). Conclusiones: En el contexto del ACVi, la TC espectral cardíaca, que incluía adquisición tardía, permitiría, eventualmente, descartar la presencia de FCE e identificar la etiología subyacente.

ABSTRACT Objective: The aim of this study was to evaluate the usefulness of spectral cardiac computed tomography (CT) angiography in patients with ischemic stroke. Methods: In the setting of COVID-19 pandemic, we incorporated the use of spectral cardiac CT in patients with ischemic stroke to rule out the presence of cardioembolic sources, thrombotic complications or myocardial damage in a single session. Since July 2020, a delayed-phase image acquisition was incorporated to cardiac CT scans in the context of ischemic stroke. We describe four representative cases of the usefulness of the method and the cardiovascular findings. Results: We present four cases recorded recorded within a 40-day period. Two patients with patients with cardioembolic source (aorta and left atrial appendage) and two with ischemic stroke of undetermined source with evidence of cardiomyopathy (ischemic and non-ischemic). Conclusions: In the setting of ischemic stroke, spectral cardiac CT with delayed acquisition could be useful to rule out the presence of cardioembolic sources and identify the underlying etiology.

Sex-Related Differences after Endovascular Treatment of Acute Ischemic Stroke in the 'Real World'.

BACKGROUND: Gender differences are often reported in the field of ischemic stroke, although most of such discrepancies were observed in randomized trials involving highly selected populations. We therefore explored gender differences regarding 90-day outcomes in large vessel occlusion (LVO) strokes receiving endovascular treatment in a real world setting. METHODS: This prospective registry included anterior and/or posterior circulation LVO strokes admitted between January 2014 and December 2019 who received mechanical thrombectomy up to 24 hours from symptoms onset or last known to be well. We explored sex-related differences in rates of functional independence (modified Rankin Scale, mRS, ≤2) at 90 days. Secondary outcomes included "National Institutes of Health Stroke Scale" (NIHSS) at 24 hours, successful reperfusion defined as modified Thrombolysis in Cerebral Infarction (mTICI) scale 2b/3, death, and symptomatic intracranial hemorrhage (sICH). RESULTS: A total of 288 LVO stroke patients comprised the study population, involving 148 (51.4%) women. Females were older (71.4±15.7 vs. 66.1±14.0 years, p=0.003) and had lower rates of coronary artery disease (15% vs. 24%, p=0.05). The median time from symptoms onset to hospital arrival was 315 min (IQR 139.5-495.0) in females and 255.0 (IQR 117.0-405.0) in males (p=0.052). Rates of mRS ≤2 at 90 days were comparable (females 46% vs. males 49%, p=0.50). Successful reperfusion was achieved in 82% of females and 89% of males (p=0.10). Rates of sICH (females 10% vs. males 13%, p=0.47) and death (females 18% vs. males 21%, p=0.50) at 90 days were similar. NIHSS at 24 hours was the strongest predictor of functional independence at 90 days (area under ROC curve 0.92 (95%CI 0.87; 0.95)]. CONCLUSIONS: Our prospective registry involving a real world setting suggests that females are equally likely to achieve good outcomes after endovascular treatment despite being older and having delayed hospital arrival compared to males. In addition, we found that NIHSS at 24 hours was the strongest predictor of functional independence at 90 days, sICH, and death.

The Use of Flow Diversion in Vessels ≤2.5 mm in Diameter-A Single-Center Experience.

BACKGROUND: Flow diversion has become an accepted treatment strategy for aneurysms; however, there are limited data on the use of these devices in small vessels ≤2.5 mm in diameter. METHODS: We performed a retrospective review of our prospectively maintained database to identify all patients treated with flow diversion between September 2009 and January 2018. We identified all patients in whom the average parent artery was ≤2.5 mm in diameter. Ruptured aneurysms were excluded from the analysis as were patients who had adjunctive coiling at the time of flow diversion. RESULTS: We identified 29 patients (22 female, 76%) with average age 56.2 ± 15.9 years (range, 21-83 years). Most aneurysms were classified as saccular (n = 21, 72.4%), with 7 fusiform aneurysms (24.2%) and 1 presumed dissecting aneurysm (3.4%). The average parent artery diameter was 2.1 ± 0.37 mm (range, 1.3-2.5 mm). Delayed angiographic follow-up was available for 18 patients at an average of 19.4 months after treatment. Fifteen patients showed Raymond-Roy classification grade 1 occlusion (94%) and 1 patient with complete filling showed Raymond-Roy classification grade 3 (6%). Four patients (13.7%) underwent repeat treatment with implantation of another flow-diverting stent in a telescoping manner. At 90 days, 2 patients had a modified Rankin Scale (mRS) score of 6, 1 from an unrelated cause and 1 from the enlarging compressive dissecting aneurysm and intraparenchymal hemorrhage. All the remaining patients had an mRS score ≤2 at 90 days, with 24 patients (83%) with an mRS score of 0. CONCLUSIONS: Flow diverters can be implanted into small vessels with a high rate of technical success and good rates of aneurysm occlusion. Dedicated devices to target these vessels should be developed.

The use of flow diverters to treat aneurysms of the posterior inferior cerebellar artery: Report of three cases.

Objective The objective of this study was to report our experience on the use of flow diverting stents placed within the posterior inferior cerebellar artery (PICA) as a treatment option for aneurysms of the PICA. Methods Three patients with aneurysms of the PICA, both ruptured and unruptured, underwent treatment of their aneurysms with placement of a single flow diverter in the PICA across the neck of the aneurysm. Adjunctive techniques such as coiling were not used. We present the angiographic and clinical follow-up data. Results The procedure was a technical success in all cases and there were no intraoperative complications. Follow-up data were available for two patients and this showed complete occlusion of the aneurysm with the PICA remaining patent. There was no evidence, either clinical or radiological, of medullary or pontine infarction. One patient died during the follow-up period from an unrelated medical illness (community acquired pneumonia). Conclusion Flow diverters can be successfully placed within the PICA to treat both ruptured and unruptured aneurysms, and they represent an alternative treatment option to endovascular coiling or microscopic neurosurgery.

The pCONus2 Neck-Bridging Device: Early Clinical Experience and Immediate Angiographic Results.

BACKGROUND: Treating wide-necked aneurysms is challenging for the interventional neuroradiologist. Recently, numerous devices dedicated to the treatment of these aneurysms have become available. We report our early experience using the pCONus2 device and present the technical success rate, clinical outcomes, and immediate angiographic occlusion rates. METHODS: We performed a retrospective review of prospectively collected data to identify patients treated with the pCONus2 device between February 2015 and February 2017. RESULTS: We identified 12 patients (10 females) treated with the pCONus2 device. The average patient age was 56.6 ± 15.8 years (range, 13-71 years). The average aneurysm dome width was 8.83 ± 5.3 mm (range, 3.8-20 mm), the average dome height was 7.23 ± 4.06 mm (range, 3.36-15 mm), and the average neck width was 5.88 ± 2.92 mm (range, 2.77-11 mm). The angulation of the aneurysm to the parent vessel varied between 0 and 78° (mean, 32.2°). Ten aneurysms were located in the anterior circulation, and 2 were in the posterior circulation. Immediate posttreatment angiography showed 11 aneurysms with modified Raymond-Roy classification (mRRC) grade I occlusion and 1 aneurysm with mRRC grade II occlusion. There were no deaths or hemorrhagic complications. Three patients developed small thrombi during treatment, all of whom were successfully treated with glycoprotein IIb/IIIa antagonists. Early angiographic follow-up data for 6 patients showed adequate aneurysm occlusion in 5 patients and aneurysm recanalization in 1 patient. CONCLUSIONS: The early results on the use of the pCONus2 device suggest that it can be useful for treating wide-necked aneurysms; however, larger studies with longer-term follow-up data are needed.

Association between hemodynamic conditions and occlusion times after flow diversion in cerebral aneurysms.

BACKGROUND: Evaluation of flow diversion treatment of intracranial aneurysms is difficult owing to lack of knowledge of the target hemodynamic environment. OBJECTIVE: To identify hemodynamic conditions created after flow diversion that induce fast aneurysm occlusion. METHODS: Two groups of aneurysms treated with flow diverters alone were selected: (a) aneurysms completely occluded at 3 months (fast occlusion), and (b) aneurysms patent or incompletely occluded at 6 months (slow occlusion). A total of 23 aneurysms were included in the study. Patient-specific computational fluid dynamics models were constructed and used to characterize the hemodynamic environment immediately before and after treatment. Average post-treatment hemodynamic conditions between the fast and slow occlusion groups were statistically compared. RESULTS: Aneurysms in the fast occlusion group had significantly lower post-treatment mean velocity (fast=1.13 cm/s, slow=3.11 cm/s, p=0.02), inflow rate (fast=0.47 mL/s, slow=1.89 mL/s, p=0.004) and shear rate (fast=20.52 1/s, slow=32.37 1/s, p=0.02) than aneurysms in the slow occlusion group. Receiver operating characteristics analysis showed that mean post-treatment velocity, inflow rate, and shear rate below a certain threshold could discriminate between aneurysms of the fast and slow occlusion groups with good accuracy (84%, 77%, and 76%, respectively). CONCLUSIONS: The occlusion time of cerebral aneurysms treated with flow diverters can be predicted by the hemodynamic conditions created immediately after device implantation. Specifically, low post-implantation flow velocity, inflow rate, and shear rate are associated with fast occlusion times.

Analysis of hemodynamics and wall mechanics at sites of cerebral aneurysm rupture.

BACKGROUND: It is thought that aneurysms evolve as the result of progressive degradation of the wall in response to abnormal hemodynamics characterized by either high or low wall shear stress (WSS). OBJECTIVE: To investigate the effects of these two different hemodynamic pathways in a series of cerebral aneurysms with known rupture sites. METHODS: Nine aneurysms in which the rupture site could be identified in three-dimensional images were analyzed. The WSS distribution was obtained from computational fluid dynamics (CFD) simulations. Internal wall stresses were computed using structural wall models under hemodynamic loads determined by the CFD models. Wall properties (thickness and stiffness) were modulated with the WSS distribution (increased or decreased in regions of high or low WSS) to test possible wall degradation pathways. Rupture probability indices (RPI) were calculated to compare different wall models. RESULTS: Most rupture sites aligned with the intrasaccular flow stream and downstream of the primary impaction zone. The model that best explained the rupture site (produced higher RPI) in eight of the nine aneurysms (89%) had thinner and stiffer walls in regions of abnormally high WSS. The remaining case (11%) was best explained by a model with thinner and stiffer walls in regions of abnormally low WSS. CONCLUSIONS: Aneurysm rupture seems to be caused by localized degradation and weakening of the wall in response to abnormal hemodynamics. Image-based computational models assuming wall thinning and stiffening in regions of abnormally high WSS were able to explain most of the observed rupture sites.