Simple measurement of aneurysm residual after treatment: the SMART scale for evaluation of intracranial aneurysms treated with flow diverters.

BACKGROUND: Primary endovascular reconstruction with flow diversion represents a fundamental paradigm shift in the technique of endovascular aneurysm treatment. Unlike coil embolization, often there remains residual post-procedural filling within the aneurysm with flow diverters, the curative reconstruction presumably occurring over a period of weeks. Thus, conventional grading scales for post-procedural aneurysm occlusion and recanalization are inadequate. The aim of this paper is to propose a new angiographic grading scale that addresses this fundamentally new treatment option. METHOD: A five-point grading scale describes the location of residual flow within the aneurysm in the venous phase [grade 1: patent aneurysm with diffuse inflow; grade 2: residual filling of the aneurysm dome (saccular) or wall (fusiform); grade 3: only residual neck (saccular) or only intra-aneurysmal filling with former boundaries covered (fusiform); grade 4: complete occlusion]. FINDINGS: Grade 0 represents any aneurysm, regardless of occlusion rate with early phase, coherent inflow jet. Intra-aneurysmal flow stagnation is categorized into: (a) none, (b) capillary phase, and (c) venous phase. Prevailing parent vessel hemodynamics with in-stent stenosis (ISS) are divided into none (ISS0), mild (ISS1), moderate (ISS2), severe (ISS3), and total (ISS4) occlusion. The proposed grading scales allow assessment of the hemodynamic consequences of stent placement on endosaccular in-flow, stasis, and location of stasis as well as parent vessel hemodynamics. CONCLUSIONS: Further studies need to show the applicability and possible predictive value of this new grading scale on the efficacy of the stent in promoting intra-aneurysmal flow stagnation, thus creating the potential to harmonize the results of future papers. This may help to optimize treatment and future device design.

Decision-making in the scheduling of endovascular treatment after brain arteriovenous malformation haemorrhage: a retrospective single centre study.

The appropriate timing for endovascular intervention after brain arteriovenous malformation (bAVM) rupture is not known. This paper aims to determine factors that lead to early endovascular intervention and to investigate whether early intervention has the same complication rate as late intervention in a single centre. All patients who underwent endovascular treatment for a ruptured bAVM at our institution in the period January 2007 and July 2010 were included in this retrospective observational study. Of 50 patients, 33 had early endovascular intervention, defined as within 30 days of haemorrhage and the remaining 17 patients had endovascular treatment at day 30 or beyond. A greater proportion of patients treated within the first 30 days were in neuro-intensive care preoperatively (51.5% vs. 23.5%, p=0.07). A 'high-risk' angioarchitectural feature was identified in more patients who had acute intervention (78.8% vs. 11.8%, p<0.0001) and targeted embolization was also more frequent in this group (48.5% vs. 5.9%, p=0.004). Nidal aneurysms, venous varices and impaired venous outflow (venous stenosis) were the principal 'high risk' features. Clinically apparent complications occurred in 10.8% of procedures with permanent neurological deficit in 3.6%. There was no directly procedure-related mortality. There was no statistically significant difference in the complication rate of early procedures compared with delayed interventions (12.5% vs. 7.4%, p=0.71). Greater initial injury severity and the presence of high-risk lesion characteristics are the factors that lead to early endovascular intervention. Early intervention is associated with a higher complication rate, but this difference is not statistically significant.

Idiopathic aneurysms of distal cerebellar arteries: endovascular treatment after rupture.

INTRODUCTION: Idiopathic ruptured aneurysms of distal cerebellar arteries (DCAAs) are rare, and their endovascular therapy (EVT) has as yet not been extensively reported. They are usually assumed to result from local arterial wall disruption rather than infection, unlike distal supratentorial artery aneurysms. This study was performed to audit their frequency, potential aetiology and results of EVT. PATIENTS AND METHODS: Using strict inclusion criteria and a database of 1715 EVT patients, we identified ten idiopathic ruptured DCAAs (0.6%) over a 13-year period (1993-2006). The series comprised six males and four females with mean age of 64 years and solitary aneurysms located on posterior inferior cerebellar artery (five patients), anterior inferior cerebellar artery (three patients) and superior cerebellar artery (two patients). Nine aneurysms were fusiform and were treated by endovascular parent artery occlusion, and one was saccular and treated by endosaccular packing. Endovascular therapy was performed with coils in seven cases, n-butyl-2-cyanoacrylate (NBCA) in two cases and with both in one case. RESULTS: Primary EVT was successful in eight patients. One patient died following a procedure-related re-bleeding and one patient required re-treatment after failed endosaccular packing. Nine patients made good or excellent clinical recoveries (modified Rankin Scale 2 or less). Focal cerebellar infarctions were seen on computed tomography images after EVT in three patients, only one of whom was symptomatic with transient dysmetria, which resolved completely during follow up. No aneurysm recanalisation was detected on late follow-up imaging up to 24 months. CONCLUSION: Ruptured DCAAs are rare. The majority are fusiform in shape and their aetiology remains uncertain. Endovascular treatment is feasible and effective. It usually requires parent artery occlusion.

Distal aneurysms of the unpaired ACA: embryologic and therapeutic aspects.

Anatomical variants of the cerebral arteries in general are frequent and due to the complex ontogenesis of these structures. Although encountered in many mammals, a single anterior cerebral artery (ACA) trunk is an infrequent finding in humans with an incidence of 3-5%. This vessel, giving rise to the arteries of both frontal lobes, is subjected to high flow volumes and distal arterial aneurysms have repetitively been encountered, mostly however before the introduction of endovascular treatment strategies. We report on five patients with acute SAH and arterial aneurysms of an unpaired ACA, who underwent coil embolisation. In all cases endovascular treatment using detachable platinum coils resulted in an at least satisfactory degree of aneurysm obliteration without parent artery occlusion or embolic infarcts. All patients had clinical and angiographic follow-up with median follow-up time of 29 months during which no aneurysm regrowth was encountered. In spite of a small patient group our results suggest, that altered flow dynamics due to enlarged single intracranial vessels may predispose to aneurysm formation and that endovascular embolisation is an appropriate treatment option in distal aneurysms of an unpaired ACA.

The in vitro and in vivo ultrasonographic appearances of the angio-seal percutaneous closure device.

PURPOSE: To assess the ultrasound appearances of the Angio-Seal device in an animal model and in twenty patients following catheterization of the femoral artery. MATERIALS AND METHODS: Ten patients were scanned within 8 hours of their procedure (early group) and 10 at two to four days (delayed group) using Acuson Aspen and Sequoia scanners. Colour flow images were taken and Doppler spectral analysis was performed proximal proximal to, at and distal to the Angio-Seal device. Early and delayed in vitro images were taken in a water bath in which the Angio-Seal device was deployed across a normal porcine aorta for comparison. RESULT: In the ten early patients colour and Doppler drop out were seen in 100 percent and 90 percent respectively compared with 90 percent and 60 percent in the delayed group. The device was seen in 30 percent and 90 percent in early and delayed groups respectively. In the in vitro study the components of the device were seen and a posterior acustic shadow noted. This shadow was less obvious and the polymer anchor more easily seen in the delayed group. CONCLUSION: The Angio-Seal device produces a consistent artifact when scanned soon after deployment. These appearances could potentially be mistaken for a vascular occlusion by the unwary in the appropriate clinical setting of acute post catheterisation lower limb ischaemia however an awareness of the normal sonographic appearances of this device would make this misinterpretation unlikely.