Nelson, Peter Kim

Background Flow-diverter stents (FDS) have become the standard of care for a wide range of intracranial aneurysms, but their efficacy/safety in the context of recurrent/recanalized aneurysms following stent-assisted coiling (SAC) is not well established. We evaluate the outcomes of FDS retreatment in a large multicenter cohort. Methods We retrospectively analyzed data from 118 patients across 22 institutions who underwent FDS retreatment for recurrent/persistent aneurysms after SAC (2008–22). The primary outcome was angiographic occlusion status at last follow-up, categorized as complete (100%), near-complete (90–99%), or incomplete (<90%) occlusion. Secondary outcomes included procedural complications and clinical outcomes measured by the modified Rankin Scale (mRS). Results A total of 118 patients (median age 57, 74.6% female) with median follow-up of 15.3 months were identified. Complete occlusion was achieved in 62.5% and near-complete occlusion in 25%. FDS deployment within the pre-existing stent was successful in 98.3% of cases. Major complications occurred in 3.4% of cases, including postoperative aneurysmal rupture with resultant mortality (1.6%) and thromboembolic events with long-term disability (1.6%). Favorable clinical outcomes (mRS 0–2) were observed in 95.1% of patients. Wider aneurysm neck diameter was a significant predictor of incomplete occlusion (adjusted OR (aOR) 1.23 per mm, P=0.044), with male sex trending towards association with non-occlusion (aOR 3.2, P=0.07), while baseline hypertension was associated with complete occlusion (aOR 0.32, P=0.048). Conclusions FDS treatment for recurrent/residual aneurysms after SAC represents a viable treatment option for these challenging cases with acceptable safety and reasonable occlusion rates, although lower than de novo FDS occlusion rates.

Abstract Initially developed for large and giant wide-necked aneurysms of the internal carotid artery, flow diverter devices are now used in almost every location safely and with effectiveness. 1-5 This video demonstrates a unique case of a giant aneurysm of the right petrous internal carotid artery in a 20-yr-old patient. This is an extremely rare location, and most of patients are asymptomatic. 3-6 Signs of compression of the seventh and eight cranial nerves can be present and even Horner syndrome and lower cranial nerves neuropathies. Nevertheless, rupture can lead to epistaxis and otorrhagia, and ultimately to hemorrhagic shock. The patient in the current report was otherwise healthy but presented with lightheadedness and dizziness for 10 d. The patient consented to the procedure. There was no history of major trauma or head and neck infection. A transradial endovascular flow diversion embolization of a giant aneurysm of the petrous internal carotid artery is herein demonstrated in a stepwise manner. A triaxial system was used to deploy 3 overlapping devices. Concepts of J-wire technique, multiple coverage, 1 and the so-called weld technique are emphasized. The role of adjunctive coiling and main reasons for failure are also discussed. 7,8 Brief cases of flow diversion embolization of aneurysms of different morphologies at different locations are used to highlight the importance of assessing vessel wall apposition and follow-up imaging.

Background Preliminary clinical studies on the safety and efficacy of the pipeline embolization device (PED) for the treatment of small/medium aneurysms have demonstrated high occlusion rates with low complications. Objective To evaluate the safety and effectiveness of the PED for treatment of wide necked small and medium intracranial aneurysms. Methods PREMIER is a prospective, multicenter, single arm trial. Patients were treated with the PED for unruptured wide necked aneurysms, measuring ≤12 mm along the internal carotid artery or vertebral artery, between July 2014 and November 2015. At 1 year post-procedure, the primary effectiveness endpoint was complete occlusion (Raymond grade 1) without major parent vessel stenosis (≤50%) or retreatment, and the primary safety endpoint was major stroke in the territory supplied by the treated artery or neurologic death. Results A total of 141 patients were treated with PEDs (mean age 54.6±11.3 years, 87.9% (124/141) women). Mean aneurysm size was 5.0±1.92 mm, and 84.4% (119/141) measured <7 mm. PED placement was successful in 99.3% (140/141) of patients. Mean number of PEDs implanted per patient was 1.1±0.26; a single PED was used in 92.9% (131/141) of patients. At 1 year, 97.9% (138/141) of patients underwent follow-up angiography with 76.8% (106/138) of patients having met the study’s primary effectiveness endpoint. The combined major morbidity and mortality rate was 2.1% (3/140). Conclusions Treatment of wide necked small/medium aneurysms with the PED results in high rates of complete occlusion without significant parent vessel stenosis and low rates of permanent neurologic complications. Trial registration NCT02186561 .

Objective There are few data regarding the effect of the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial results on the management of intracranial atherosclerotic disease (ICAD). We sought to understand the impact of the SAMMPRIS trial on current ICAD clinical practices and future trial design. Methods During the ICAD symposium at the 2012 International Stroke Conference, electronic data were collected regarding attendees’ clinical management of ICAD and opinions on the feasibility of future trials post-SAMMPRIS. Results 217 attendees from different specialties, including neurologists (57%), neurointerventionalists (9%) and neurosurgeons (5%), participated in the session. The majority of respondents (77%) indicated that the results of SAMMPRIS have impacted their consideration for intracranial stenting. Post-SAMMPRIS, 84% selected ‘SAMMPRIS-style’ medical management for the treatment of ICAD. For patients with ICAD who failed aggressive medical therapy, 82% would consider an alternative approach to continuing medical therapy (30% considered clinical trial enrollment, 28% suggested angioplasty and stenting and 24% angioplasty). The majority of participants (85%) were willing to randomize patients with symptomatic ICAD in future trials. For the next ICAD trial, 29% indicated that angioplasty alone should be compared with aggressive medical therapy. Conclusions Our polling results suggest that the SAMMPRIS trial has had an impact on the current treatment of ICAD. Treatment of patients who failed medical therapy varied widely from aggressive medical therapy to balloon angioplasty, stenting or enrollment in future clinical trials. The willingness to continue clinical trials and randomize patients supports the need for future ICAD studies.