Leonardo Renieri

Treatment of two blood blister-like aneurysms with flow diverter stenting

Purpose Neurosurgical and endovascular treatment of fragile and recurrent aneurysms of the non-branching portion of the internal carotid artery, known as blister-like aneurysms, is challenging. The aim of this paper is to describe two cases of ruptured blister-like aneurysms of the internal carotid artery and of the vertebral artery at the origin of the postero-inferior cerebellar artery, which were both treated with flow diverter (FD) stents. Methods Two patients with a sub-arachnoid hemorrhage secondary to the rupture of a blister-like aneurysm were treated with a Pipeline (ev3, Irvine, California, USA) stent. Digital subtraction angiography and clinical follow-up were carried out. Results Both patients treated with FD stents had an excellent clinical (modified Rankin Scale, mRS 0) and angiographic outcome. In both cases the aneurysms were completely excluded after 6 months. Conclusions Although the use of this endovascular approach is still debated because of poor experience and pharmacological limitations, FD stents may represent a valid alternative approach for treatment of this aneurysm subtype.

Endovascular Treatment of Deep Hemorrhagic Brain Arteriovenous Malformations with Transvenous Onyx Embolization

SUMMARY: Brain AVMs are a rare cause of cerebral hemorrhage and SAH, and their treatment is still debated. The aim of this study was to describe a novel endovascular approach with transvenous embolization of deep hemorrhagic brain AVMs. Five patients (3 females, 2 males; mean age, 33.2 years) underwent a transvenous embolization of a deep hemorrhagic brain AVM at our institution between February and April 2012. Clinical and angiographic data at the end of the procedure and after 6 months are reported. All the AVMs were completely obliterated, and no intra- or postprocedural complications occurred. The clinical outcome was unchanged or improved in all patients. Transvenous endovascular treatment may be considered in small, hemorrhagic, and deep AVMs with single deep drainage in those cases in which neurosurgical and radiosurgical treatment might not be indicated.

Assisted coiling of saccular wide-necked unruptured intracranial aneurysms: stent versus balloon

Background and purpose Assisted coiling with stents or balloons enables a higher percentage of complete occlusions of saccular unruptured intracranial aneurysms to be achieved with a reasonable complication rate. The aim of this study was to compare stent-assisted coiling and the balloon remodeling technique in terms of efficacy, stability, and safety for the treatment of comparable unruptured saccular intracranial aneurysms. Materials and methods 268 patients with 286 saccular unruptured wide-necked intracranial aneurysms were treated at our institution with stent- or balloon-assisted coiling and retrospectively reviewed. Statistical analysis was performed to assess significant differences between the two groups. Results The rate of complete occlusion at the end of the procedure was higher with stent-assisted coiling than with balloon-assisted coiling (86.8% vs 78%) and the same results were also observed after 6 months (92.1% vs 77.6%; p=0.05). About 50% of major recurrences occurred in large to giant aneurysms (p<0.001). The overall complication rate was similar in the stent-assisted and balloon-assisted groups (10.3% vs 9.3%). Independently of the technique, a higher complication rate was observed with bifurcational aneurysms, particularly in the middle cerebral artery (p=0.016). Conclusions Stent-assisted coiling achieved better results in terms of complete occlusion and stability than balloon-assisted coiling with a lower rate of recurrence without being associated with a higher risk of intraprocedural complications. Bifurcational and large to giant aneurysms were associated with higher complication rates and higher recurrence rates, respectively, and still represent a challenge for both techniques.

Y-stent assisted coiling of bifurcation aneurysms with Enterprise stent: long-term follow-up

Background Y-stent assisted coiling has been proposed for the treatment of wide-neck bifurcation aneurysms, but there are many technical variations. We report our single-center experience of Y-stent assisted coiling of bifurcation aneurysms with the closed cell Enterprise stent in order to evaluate the safety and long-term results of this technique. The literature on Y-stenting and its hemodynamic effects are reviewed. Methods Fifty-two consecutive patients with wide-neck bifurcation aneurysms underwent Y-stent assisted coiling with two Enterprise stents. The procedure was completed in 48 cases (92.3%) and technical failure occurred in 4 cases (7.3%). Cases performed with other stents were excluded. All procedures were performed under double antiplatelet therapy. Periodic clinical and neuroradiological follow-up was performed. Results Mean neuroradiological follow-up time was 26 months. Complete immediate occlusion was obtained in 87.5% of patients. Two remnants had regrown at follow-up and were recoiled, achieving complete occlusion. The late neuroradiological occlusion rate was: complete occlusion 93.6%, neck remnant 4.3%, sac remnant 2.1%. No in-stent stenosis was detected at follow-up. Among the 48 procedures, two complications occurred (4.2%). Mortality was 2.1%. No delayed ischemic stroke occurred. Conclusions Y-stent assisted coiling has a high immediate occlusion rate and very good long-term stability. The procedure is relatively safe, although the complication and mortality rates are not negligible. Two Enterprise stents can be safely used for Y-stenting and, indeed, offer the advantage of easier catheterization, delivery and deployment into distal and tortuous vessels than open cell stents.

Transvenous embolization: a report of 4 pediatric cases

The treatment of brain arteriovenous malformations (AVMs) in children has always been a challenge for interventionalists, neurosurgeons, and radiosurgeons. Endovascular embolization is usually performed through transarterial access, but in selected cases the transvenous approach can be considered. The authors of this report aimed to evaluate the efficacy of transvenous embolization in very selected pediatric cases. They describe 4 children treated using transvenous embolization for AVMs that were small, had a single drainage vein, and were deeply located or had a difficult arterial access. The 6-month angiographic and clinical follow-ups are reported as well. In all cases, complete occlusion of the AVM was achieved with no side effects for the patient. Transvenous embolization may represent a promising alternative therapeutic option in very selected cases.

Double Arterial Catheterization Technique for Embolization of Brain Arteriovenous Malformations With Onyx

BACKGROUND Arteriovenous malformation (AVM) treatment is multidisciplinary, and the patient may undergo embolization, neurosurgery, or radiosurgery combined. Great improvement in endovascular techniques was provided by the introduction of Onyx with different kinds of approach. OBJECTIVE To evaluate the efficacy and the safety of Onyx embolization of brain AVMs with the double arterial catheterization technique (DACT). METHODS This was a retrospective study. From January 2006 until June 2011, 61 AVMs eligible for the DACT were treated. Forty-one of the 61 AVMs were treated with single arterial catheterization technique and 20 of 61 with DACT; patient age and Spetzler-Martin AVM grade were similar in the 2 groups. RESULTS In the DACT group, we obtained complete occlusion of the nidus in all small AVMs, whereas in the single arterial catheterization technique group, we obtained complete occlusion in only 1 of the 36% of the cases. Among the medium-size AVMs, there were no significant differences in the 2 groups, but we performed fewer procedures per patient when we used the DACT (1.4 vs 2.2). In the DACT group, we observed fewer hemorrhagic complications (3.4% vs 12.5% per procedure) and lower morbidity (5% vs 7% per patient) and mortality (0% vs 2.4%) rates. CONCLUSION The DACT in multifeeder AVMs may lead to a higher occlusion rate of the nidus for small AVMs and reduce the number of procedures, ensuring a higher standard of safety because of the possibility of managing the progression of Onyx into venous drainage.

Endovascular treatment with ‘kissing’ flow diverter stents of two unruptured aneurysms at a fenestrated vertebrobasilar junction

Background and purpose Fenestration of the vertebrobasilar junction (VBJ) is a rare condition which may be associated with the presence of aneurysms. The endovascular approach is usually the first-line treatment in these cases since the location of the aneurysm may be unsuitable for a surgical approach. This anatomical variation may even influence the endovascular strategy, particularly in those cases in which the sacrifice of a vessel could be avoided. This paper describes an innovative approach of flow diversion in such challenging situations. Methods Two women were admitted after an occasional diagnosis of an aneurysm arising from a fenestrated VBJ. In both cases the endovascular approach was performed with two flow diverter stents and dual antiplatelet therapy was administered for 6 months. Results Complete exclusion of the two aneurysms was obtained after 6 and 7 months, respectively, and the clinical outcome was excellent. Conclusions Endovascular treatment of unruptured aneurysms located on a fenestrated VBJ with flow diverter stents represents a valid therapeutic approach with excellent clinical and radiological outcomes.

PulseRider for Treatment of Wide-Neck Bifurcation Intracranial Aneurysms: 6-Month Results

BACKGROUND/OBJECTIVE PulseRider is a new endovascular stent dedicated to treat bifurcation intracranial aneurysms with a wide neck. Our purpose was to evaluate 6-month clinical and anatomic results of the device when used to facilitate endovascular coiling of wide-neck bifurcation aneurysms. METHODS Unruptured intracranial aneurysms coiled with PulseRider, in 6 European centers and 1 U.S. center, were retrospectively reviewed from June 2014 to October 2015. Immediate and 6-month results were evaluated independently by using the Raymond classification scale. Recanalization was defined as worsening, and progressive thrombosis was defined as improvement on the Raymond scale. RESULTS Nineteen patients (10 women, 9 men; mean age, 63 years) harboring 19 bifurcation aneurysms (mean dome size, 8.8 mm; mean neck size, 5.8 mm) were included. Immediate angiographic outcome showed 11 complete aneurysm occlusions, 6 neck remnants, and 2 residual aneurysms. Follow-up at 6 months, obtained in all patients, included 12 complete aneurysm occlusions (63.1%), 6 neck remnants (31.6%), and 1 residual aneurysm (5.3%). Adequate occlusion (defined as complete occlusion and neck remnant combined) was observed in 94.7%. Progressive thrombosis was observed in 2 cases (10.6%) and recanalization in 1 case (5.3%). There was no in-stent stenosis or jailed branch occlusion. No bleeding was observed during the follow-up period. Permanent morbidity rate was 5.3% (1/19), and the mortality rate was 0% at 6 months. CONCLUSIONS The PulseRider allows endovascular treatment of wide-neck bifurcation intracranial aneurysms. Larger series are needed to confirm our preliminary results.

Effects of Hyper-Early (<12 Hours) Endovascular Treatment of Ruptured Intracranial Aneurysms on Clinical Outcome

Despite the encouraging results obtained with the endovascular treatment of ruptured intracranial aneurysms, few data are available on the effects of the timing of this approach on clinical outcome. The aim of our study was to evaluate the effects of the hyper-early timing of treatment and of pre-treatment and treatment-related variables on the clinical outcome of patients with ruptured intracranial aneurysms. Five hundred and ten patients (167 M, 343 F; mean age 56.45 years) with 557 ruptured intracranial aneurysms were treated at our institution from 2000 to 2011 immediately after their admission. The total population was divided into three groups: patients treated within 12 hours (hyper-early, group A), between 12–48 hours (early, group B) and after 48 hours (delayed, group C). A statistical analysis was carried out for global population and subgroups. Two hundred and thirty-four patients (46%) were included in group A, 172 (34%) in group B and 104 (20%) in group C. Pre-treatment variables (Hunt&Hess, Fisher grades, older age) and procedure-related variable (ischaemic/haemorrhagic complications) showed a significant correlation with worse clinical outcomes. The hyper-early treatment showed no correlation with good clinical outcomes. The incidence of intraprocedural complications was not significantly different between the three groups; 1.2% of pre-treatment rebleedings were observed. The hyper-early endovascular treatment of ruptured intracranial aneurysm does not seem to be statistically correlated with good clinical outcomes although it may reduce the incidence of pre-treatment spontaneous rebleedings without being associated with a higher risk of intraprocedural complications. However, since no significant differences in terms of clinical outcome and pre-treatment rebleeding rate were observed, a hyper-early treatment is not be supported by our data.

Semi-quantitative and qualitative evaluation of pial leptomeningeal collateral circulation in acute ischemic stroke of the anterior circulation: the Careggi Collateral Score.

INTRODUCTION The imaging of ischemic penumbra in acute stroke is a debated issue and establishing commonly accepted criteria is difficult. Computerized tomography-perfusion studies conducted in animals have showed that the modifications occurring in the brain parenchima are part of a dynamic and progressive process involving the microcirculation. The purpose of this paper is to propose a new angiographic classification of collateral circulation in patients with acute ischemic stroke, with a possible correlation with the clinical outcome. MATERIALS AND METHODS The basal angiograms of 57 patients with acute ischemic stroke is the territory of anterior circulation secondary to a major occlusion, who underwent endovascular treatment, were retrospectively reviewed and collaterals were classified according to our novel Careggi Collateral Score in 6 grades (0-6). The clinical outcome after 3 months was evaluated with modified Rankin Scale. A ROC (receiver operating characteristic) curve analysis identified a cut-off value of 1. RESULTS Patients with favorable collateral circulation (grades 2-5) showed a significant correlation with good clinical outcome (modified Rankin Scale < or = 2). CONCLUSIONS The Careggi Collateral Score resulted a useful tool to evaluate the chance of obtaining a favorable result with endovascular treatment in patients with acute ischemic stroke in the anterior circulation secondary to the occlusion of a major artery.