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.

Basilar artery origin of an orbital artery - A rare variant and review of the embryology of the orbital arterial supply.

We present a patient with separation of the arterial supply to the globe and the extra-ocular muscles. The ophthalmic artery originates from the typical adult location and supplies only the globe. Arising from the basilar artery was a branch that supplies the extra-ocular muscles. There was no apparent connection between these vessels around the optic nerve and no evidence of supply from the external carotid artery. We discuss the embryology of the ophthalmic artery from the point of view of Padget and Lasjaunias and offer our opinion on the on-going controversy. We believe this is the first case to highlight the trigeminal-primitive maxillary-stapedial anastamotic pathway.

The use of flow diverters to treat small (≤5 mm) ruptured, saccular aneurysms.

BACKGROUND: There is limited published literature on the use of flow diverting stents (FDS) to treat ruptured intracranial aneurysms in the acute stage. We present our experience of using FDS to treat small (≤5 mm) ruptured aneurysms. METHODS: We retrospectively identified all patients with ≤5 mm ruptured aneurysms treated exclusively with FDS between February 2009 and February 2016. We recorded demographic data, the Hunt and Hess score, aneurysm location and size, therapeutic intervention, immediate angiographic and clinical result, and clinical and radiological follow-up information. RESULTS: We identified seven patients (four females) with average age 59.8 ± 10 years (range 48-75). The average aneurysm fundus size was 2.7 ± 0.76 mm (range 1-4 mm). The average time from ictus to treatment was 6.3 days (range 1-14 days) and there were no cases of repeat rupture prior to treatment or intraoperative rupture. Angiographic follow-up was available in five patients. At initial follow-up, aneurysms (100%) were completely occluded raymond roy classification 1 (RRC 1). None of the aneurysms re-ruptured following treatment. Clinically, six patients were discharged with good functional outcome modified Rankin Score (mRS ≤2). There were no mortalities. CONCLUSION: The use of FDS to treat small, ruptured, saccular aneurysms is feasible; however, the use of FDS should not be considered first-line treatment. Further studies are required to determine the safety and efficacy of the use of FDS in the acute situation.

Endovascular Thrombectomy in Acute Ischemic Stroke: Outcome in Referred Versus Directly Admitted Patients.

PURPOSE: Endovascular mechanical thrombectomy (mTE) in acute ischemic stroke due to large cerebral artery occlusion is effective and safe. The procedure is currently offered by specialized hospitals. Physicians from smaller hospitals need to refer patients to stroke centers. Secondary referrals involve delays for transportation. Little is known about effects of distant referrals on outcome and complications as compared to direct admittance. METHODS: To evaluate the effects of referral patterns on outcome and safety, we analyzed 941 patients with anterior circulation stroke receiving mTE between January 2010 and December 2015. Patients were divided into three groups: directly admitted patients (DAP), inner-city transfers (ICT) and long-distance referrals (LDR). We assessed (1) procedural parameters (2) frequency of good functional outcome (mRS ≤2 at 3 months) and (3) mortality rates. RESULTS: Referrals had a significantly longer imaging-to-groin time compared to DAP (median 150 min vs. 85 min, p <0.001), the same was true for LDR vs. ICT (median 157 min vs. 133.5 min, p <0.001). Time to recanalization was significantly longer for referrals compared to DAP (median 348 min vs. 260 min, p <0.001). There was no significant difference in the frequency of good functional outcome (DAP 39.5%, ICT 35.1%, LDR 37.0%; p =0.709), all-cause mortality at day 90 (DAP 31.5%, ICT 23.0%, LDR 27.0%; p =0.212) and the rate of symptomatic intracranial hemorrhage (p =0.834). CONCLUSION: Timing remains a critical factor in acute ischemic stroke treatment by endovascular means. Long distance referral to specialized neurovascular centers with high recanalization rates, however, does allow for a good functional outcome in a significant number of patients.

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.

The Fate of Side Branches Covered by Flow Diverters-Results from 140 Patients.

BACKGROUND: Flow diverter stents (FDS) are a recognized treatment option for intracranial aneurysms. There remain ongoing concerns regarding the safety of FDS, especially regarding the fate of covered side branches. We report the patency of side branches covered by FDS. METHODS: We retrospectively reviewed our database of prospectively collected information for all patients treated with FDS for an unruptured saccular aneurysm of the clinoid, ophthalmic, and terminating segments of the internal carotid artery between September 2009 and July 2016. The aneurysm location, fundus size, and the state of covered branches at last angiography were recorded compared with preoperative angiography. RESULTS: We identified 140 patients, with 147 aneurysms, who met our inclusion criteria. Five patients had bilateral aneurysms. There were 31 male patients in our cohort (21.9%) and the mean average age was 56.2 ± 13.7 years. Sixty-seven aneurysms arose from the communicating, 58 from the ophthalmic, and 22 from the clinoidal segments. At last follow-up (mean, 22.3 months) 116 aneurysms were completely occluded (78.3%). On the most recent angiogram, 7 ophthalmic (5.3%), 20 posterior communicating (42.6%), 0 anterior choroidal (0%), and 2 anterior cerebral arteries (14.3%) were completely occluded. Reduced vessel caliber was seen in 11 ophthalmic (8.3%), 3 posterior communicating (6.4%), 0 anterior choroidal, and 6 anterior cerebral arteries (42.9%). One patient died during follow-up. CONCLUSIONS: The side branch occlusion rate was 20% and included ophthalmic, posterior communicating, and anterior cerebral arteries. Consistent with other studies, we did not see occlusion of the anterior choroidal artery.

Intra-aneurysmal hemodynamics: evaluation of pCONus and pCANvas bifurcation aneurysm devices using DSA optical flow imaging.

BACKGROUND: Implantation of self-expanding stents from the parent artery into the sac of a bifurcation aneurysm is regularly used to facilitate endovascular coil occlusion with the so-called waffle cone technique (WCT). Self-expanding aneurysm bridging stents like Solitaire AB, can be used; however, bifurcation devices like pCONus and pCANvas are especially designed for WCT. These devices provide additional support for coil implantation owing to intraluminal nylon fibers (pCONus) or membranes (pCANvas) covering the intracranial aneurysm neck. OBJECTIVE: Assessment of the intra-aneurysmal hemodynamic impact of these three devices: a regular intracranial stent (Solitaire AB) and two bifurcation devices (pCONus and pCANvas). MATERIAL AND METHODS: An in vitro experiment was set up using a silicone model of a basilar tip aneurysm filled with blood mimicking fluid under a pulsatile circulation. Solitaire AB, pCONus, and pCANvas were successively implanted in the model for hemodynamic evaluation. High frame rate DSA series were acquired under various conditions. Intra-aneurysmal flow changes, including mean aneurysm flow amplitude ratio (R), were subsequently assessed by the optical flow method, measuring the detector velocity field before and after device implantations. RESULTS: pCONus and Solitaire minimally reduced the intra-aneurysmal flow (R=0.96, p=0.17 and R=0.91, p=0.01, respectively), whereas pCANvas strongly diminished the intra-aneurysmal flow (R=0.41, p=5×10-12). CONCLUSIONS: Waffle cone deployment of stents and technique-specific devices had no undesirable effect on the intra-aneurysmal flow. In particular, no increased flow was redirected into the aneurysm sac. The intraluminal membrane of the pCANvas strongly reduced the intra-aneurysmal flow, potentially preventing recanalization problems.

Pipeline embolization device for the treatment of intra- and extracranial fusiform and dissecting aneurysms: initial experience and long-term follow-up.

BACKGROUND: Flow-diverting stents offer a promising treatment option for complex aneurysms. OBJECTIVE: To evaluate the safety and efficacy of the Pipeline embolization device (PED) in the treatment of fusiform and dissecting aneurysms. METHODS: Sixty-five consecutive patients with 69 fusiform and dissecting aneurysms underwent endovascular treatment with the use of the PED. Target vessels included the internal carotid artery (n = 28), middle cerebral artery (n = 2), anterior cerebral artery (n = 1), vertebral artery (n = 20), basilar artery (n = 17), and posterior cerebral artery (n = 1). An average of 3.0 PEDs per target vessel were deployed. RESULTS: Exclusion of the aneurysm(s) immediately after PED deployment was not observed. Angiographic follow-up examinations were performed in 63/65 patients (67/69 lesions). They showed complete cure of the target lesion in the first follow-up angiography (3.4 months mean interval) in 24 (36%) cases, partial elimination in 30 (45%), and no improvement in 13 (19%). After the latest follow-up (>1 digital subtraction angiography, n = 49, 27.4 months mean interval) complete cure of the target lesion was observed in 33 (67%), partial elimination in 14 (29%), and no change in 2 (4%). Taking all follow-up examinations together, 39/67 (58%) aneurysms were cured. The morbidity and mortality in the entire series were 5% and 8%, respectively. CONCLUSION: Flow diverters offer a promising treatment option in fusiform and dissecting aneurysms. The introduction of flow diverters with different densities might help to identify the optimal amount of coverage needed given different anatomic presentations of fusiform and dissecting aneurysms.

Prevention of intracranial in-stent restenoses: predilatation with a drug eluting balloon, followed by the deployment of a self-expanding stent.

PURPOSE: Stenting in intracranial atherosclerotic disease (ICAD) is increasingly debated, due to issues of procedural safety, technical efficacy, and in-stent recurrent stenoses (ISR). In the present study, feasibility, safety, and efficacy of angioplasty using a drug-eluting balloon (DEB) followed by the implantation of a self-expanding stent (Enterprise) were evaluated for the treatment of ICAD lesions. METHODS: Fifty-two patients (median age: 71 years; range: 54-86 years; male/female ratio 37:15) underwent stenting of high-grade ICAD lesions between February 2010 and November 2011 in a single center. Angioplasty using a paclitaxel coated SeQuent Please (B. Braun, Germany) or DIOR (Eurocor, Germany) coronary PTCA balloon, followed by the implantation of a self-expanding stent (Enterprise, Codman, USA) was performed in 54 lesions. Angiographic and clinical follow-up was performed at 6 and 12 weeks, 6 and 12 months, and yearly thereafter. Technical success rate, periprocedural complications, occurrence of recurrent ischemic symptoms, and the development of an ISR were analyzed. RESULTS: Angioplasty using a DEB followed by stent implantation was successfully performed in 44 (81 %) cases. DEB insertion failed in 19 % of the cases and angioplasty was finally performed using a conventional PTCA balloon. The combined procedure related permanent neurologic morbidity and mortality rate (stroke, ICH, and subarachnoid hemorrhage) at 30 days and beyond was 5 %. Angiographic and clinical follow-up were obtained in 33 (61 %) lesions in 32 patients. Recurrent stenosis was seen in one (3 %) lesion. CONCLUSION: Angioplasty and stenting using a DEB is safe and yields encouragingly low ISR rates. Further technical developments to improve lesion accessibility are, nevertheless, mandatory.

Does mechanical thrombectomy in acute embolic stroke have long-term side effects on intracranial vessels? An angiographic follow-up study.

PURPOSE: Mechanical thrombectomy (mTE) proved to be effective treating acute vessel occlusions with an acceptable rate of procedural complications. Potential long-term side effects of the vessel wall trauma caused by mechanical irritation of the endothelium are unknown up to now. METHODS: From a retrospectively established database of 640 acute stroke treatments, we selected 261 patients with 265 embolic vessel occlusions treated successfully by mTE without permanent implantation of a stent. Analysis comprised the type of devices used and the number of passes performed. Digital subtraction angiography immediately after treatment was evaluated for vasospasm, dissection, and extravasation. Control angiographic images were evaluated for any morphological change compared to the immediate posttreatment angiographic run. RESULTS: Recanalization was achieved with a median of one (range 1-10) mTE maneuvers. Vasospasm occurred in 69 territories (26.0 %) and was treated with glyceroltrinitrate in three. Dissection was observed in one vessel (0.4 %). Intraprocedural hemorrhage in two patients (0.8 %) was either wire or device induced. Follow-up digital subtraction angiography was available for 117 territories after a median of 107 days, revealing target vessel occlusion in one segment (0.9 %) and a de novo stenosis of four segments (3.4 %). All findings were clinically asymptomatic. Posttreatment vasospasm was more frequent in patients with de novo stenosis and occlusion (p = 0.038). CONCLUSION: De novo stenoses and occlusions occur in a small proportion of patients after mTE. Because all lesions were clinically asymptomatic, this finding does not affect the overall benefit of the treatment. Vasospasm may predict late vessel wall changes.

Intracranial thrombectomy using the Solitaire stent: a historical vignette.

INTRODUCTION: The endovascular treatment of acute ischemic stroke has been revolutionized in the past years by the introduction of new devices for mechanical thrombectomy. Several tools were already available in 2008. The majority allowed the recanalization of acutely occluded intracranial arteries with acceptable levels of safety and efficacy, and with occasional failures. CASE PRESENTATION: On 3 March 2008, a 67-year-old woman was treated 3.5 h after the clinical onset of a right hemispheric stroke due to an embolic middle cerebral artery (MCA) M1 occlusion. The National Institutes of Health Stroke Scale (NIHSS) score prior to treatment was 10. Mechanical thrombectomy with a microbrush yielded a significant amount of thrombotic material without recanalization. Given the urgency of the situation, the uncertain outcome in the case of a persistent occlusion of the right M1 segment and the fact that no other device was available, a Solitaire stent was deployed within the occluded right M1 segment. After several minutes of incubation, the expanded stent was slowly withdrawn under continuous aspiration with instantaneous removal of the entire thrombus and complete recanalization of the right MCA with reperfusion of the whole MCA supply territory. Digital subtraction angiography showed neither peripheral emboli nor vasospasm. The patient made a complete clinical recovery with an NIHSS score of 0 at the 30 day follow-up. CONCLUSION: The Solitaire stent was initially developed for the endovascular treatment of wide necked intracranial aneurysms but has been demonstrated to be safe and efficacious for intracranial thrombectomy. This was the first successful human clinical use of a Solitaire stent for this purpose and the ignition spark for the development of a whole generation of new devices, now called stent retrievers.