Dan Meila

Subcallosal artery stroke: infarction of the fornix and the genu of the corpus callosum. The importance of the anterior communicating artery complex. Case series and review of the literature

IntroductionDespite the variable anatomy of the anterior communicating artery (AcoA) complex, three main perforating branches can be typically identified the largest of which being the subcallosal artery (ScA). We present a case series of infarction in the vascular territory of the ScA to highlight the anatomy, the clinical symptomatology, and the presumed pathophysiology as it pertains to endovascular and surgical management of vascular pathology in this region.MethodsIn this retrospective multicenter case series study of patients who were diagnosed with symptomatic ScA stroke, we analyzed all available clinical records, MRI, and angiographic details. Additionally, a review of the literature is provided.ResultsWe identified five different cases of ScA stroke, leading to a subsequent infarction of the fornix and the genu of the corpus callosum. The presumed pathophysiology in non-iatrogenic cases is microangiopathy, rather than embolic events; iatrogenic SCA occlusion can present after both surgical and endovascular treatment of AcoA aneurysms that may occur with or without occlusion of the AcoA.ConclusionStroke in the vascular territory of the ScA leads to a characteristic imaging and clinical pattern. Ischemia involves the anterior columns of the fornix and the genu of the corpus callosum, and patients present with a Korsakoff’s syndrome including disturbances of short-term memory and cognitive changes. We conclude that despite its small size, the ScA is an important artery to watch out for during surgical or endovascular treatment of AcoA aneurysms.

Low incidence of paradoxical platelet activation by glycoprotein IIb/IIIa inhibitors

The human platelet antigen-1 (HPA-1, Pl(A)) polymorphism has been proposed to influence the inhibitory actions of abciximab. Thus, we hypothesized that this polymorphism might also be the cause for paradoxical activation of platelets by GPIIb/IIIa inhibitors. The effects of abciximab (1-10 microg/ml), tirofiban (3-30 nM), or eptifibatide (0.3-3 microg/ml) on basal and ADP (3 microM)-induced CD62P externalization were measured in n=62 healthy blood donors and n=177 patients with stable coronary artery disease. All subjects were genotyped for the human platelet antigen-1 (HPA-1, Pl(A)) polymorphism by GALIOS(R) and fluorescence correlation spectroscopy. Although a significant platelet hyperreactivity was observed in the patients, the HPA-1 genotype did not influence basal or ADP-induced CD62P expression. A moderate (twofold) stimulation of CD62P expression by abciximab but not by tirofiban or eptifibatide was observed in one patient. Interestingly, this patient carried the HPA-1 b/b genotype. In no other subject any activation of platelets by GP IIb/IIIa inhibitors was observed and there were no statistically significant differences between HPA-1 genotypes with respect to the effects of GP IIb/IIIa inhibitors on basal or ADP-stimulated CD62P expression. It is concluded that paradoxical platelet activation by abciximab is a rare (<2%) phenomenon. HPA-1 b/b genotype might be a contributing factor but clearly does not predict platelet activation by GP IIb/IIIa inhibitors.

Kissing-Y stenting for endovascular treatment of complex wide necked bifurcation aneurysms using Acandis Acclino stents: results and literature review.

Introduction Y-configured stent assisted coiling is a promising therapeutic option to ensure safe coil embolization and preserve the affected arteries in complex wide necked aneurysms. We present our experience with self-expanding Acandis Acclino stents for the treatment of complex aneurysms using the kissing-Y technique. Methods We retrospectively reviewed seven patients with seven complex aneurysms (three anterior communicating artery (AcomA), two middle cerebral artery, one basilar artery/superior cerebellar artery, and one vertebral artery/posterior inferior cerebellar artery) who were treated with the kissing-Y technique by stent assisted coiling from June 2013 to July 2014, with follow-up until January 2015. DSA follow-up was up to 17 months, with a mean follow-up period of 10 months. Six patients were treated electively and one in the acute phase of a subarachnoid hemorrhage. In all cases, closed cell Acandis Acclino stents were used. We evaluated procedural complications, clinical outcomes, and mid term angiographic follow-up. Additionally, a literature review is provided. Results In all patients, stents were successfully placed and implanted. One patient developed a periprocedural thromboembolic complication not directly related to the stents. No other periprocedural or postprocedural complications were encountered. Follow-up examinations showed stable and total occlusion of all coiled aneurysms. Conclusions The results of our study show that the kissing-Y technique using closed cell Acandis Acclino stents followed by coil embolization is a feasible treatment option for selected complex bifurcation aneurysms.

Endovascular treatment of head and neck arteriovenous malformations: long-term angiographic and quality of life results

Aim To present the long-term angiographic and subjective results of patients with head and neck arteriovenous malformations (HNAVMs) after endovascular treatment. Methods We retrospectively analyzed the medical files of 14 patients with HNAVM who were treated between 2000 and 2014. The treatment of choice was a transarterial superselective microcatheter-based approach followed by embolization using liquid embolic agents. The patients were asked to answer a quality of life questionnaire about the following symptoms before and after treatment: pain, functional impairment, cosmetic deformity, impairment in daily life, and bleeding. Results Complete or >90% closure of the AVM was achieved in 6 of 14 patients (43%). >50% shunt reduction was achieved in 10 patients (71%). Three complications were encountered in a total of 86 interventional procedures. Six patients presented with bleeding which was cured in all cases (100%). Four of the 14 patients (29%) specified pain which was resolved in two of them. Another six patients (43%) presented with functional impairment; four were cured and two noted an improvement. All 14 patients presented with cosmetic concerns; four were cured and eight experienced a clearly visible improvement. Nine of 13 patients (69%) presented with impairment in daily life which was resolved in five patients and four reported an improvement. Conclusions Endovascular embolization is a well-tolerated therapy for HNAVM with a low complication rate. Good angiographic results, positive subjective results, and improvement in different aspects of quality of life can be achieved.

Endovascular treatment of complex intracranial aneurysms using Acandis Acclino stents

Objective To determine the safety and effectiveness of a new low-profile, laser-cut, closed-cell stent system in the treatment of complex intracranial aneurysms. Methods A total number of 43 patients with complex intracranial aneurysms were treated using 60 Acandis Acclino stent systems (follow-up 2012–2016; mean 11 months). 36 patients presented with wide-necked intracranial aneurysms, dissecting aneurysms were seen in 7 patients. 39 patients received stent-assisted coiling. We analyzed demographic data and follow-up results. Results Sixty stents were successfully deployed. In one paraophthalmic internal carotid artery aneurysm the stent could not be placed. Thirty-three wide necked aneurysms were treated by single or multiple stent-assisted coiling. Complete occlusion was achieved in 31 of those cases (94% Raymond−Roy occlusion classification, RROC 1). Two patients showed stable residual aneurysmal filling (RROC 3). In three wide-necked aneurysms, sole stenting was the preferred treatment. For dual stent-assisted procedures the kissing-Y stenting technique was successfully performed in 11 aneurysms. In all dissecting aneurysms constructive therapy with stenting and preservation of the affected parent artery was achieved. Additional subsequent coil embolization was intentionally planned and successfully performed in 6 of the 7 dissecting aneurysms. The overall directly procedure-related complication rate was 7%, including one death. Conclusions Endovascular treatment of complex intracranial aneurysms using Acclino stents is a feasible and safe procedure with low complication rates. Even severe cases can be treated among others using the kissing-Y stenting technique, with good mid-term results.

Vascular angular remodeling by kissing-Y stenting in wide necked intracranial bifurcation aneurysms

Introduction Single stent deployment leads to a change in vascular geometry in wide necked bifurcation aneurysms. In some complex cases, the use of the single stent technique might not be sufficient or may not be feasible. The kissing-Y stenting technique appears to be an alternative endovascular treatment option. The aim of this study was to evaluate the effects of the kissing-Y stenting technique on vascular angular remodeling. Methods 21 patients with wide necked intracranial bifurcation aneurysms at different sites (10 anterior communicating artery, 6 middle cerebral artery, 3 basilar artery, 1 vertebral artery/posterior inferior cerebellar artery, 1 internal carotid artery/posterior communicating artery) were treated with 44 closed cell stents (follow-up 2012–2016) using the kissing-Y stenting technique. We analyzed vascular angle geometry between the mother and both affected daughter vessels by digital subtraction angiography, before and after stent deployment, using standard working projections. Results Endovascular treatment of wide necked intracranial aneurysms using the kissing-Y stenting technique significantly decreased the angle between the bifurcation branches from 130.4±9.5° to 91.5±9.1° (p<0.0001). Conclusions Kissing-Y stenting in wide necked bifurcation aneurysms leads to vascular angular remodeling of both affected branches. The resulting straightening of the bifurcation angle may prevent aneurysmal recurrence.

Interventional Treatment in AVM

Due to growing understanding of pathophysiological relationships and the continuing progress in the development of endovascular materials, the prevalence, significance, and need of interventional treatment in AVM have continued to increase. This chapter first presents the techniques and materials employed in interventions of AVM. Based on this description, the application of endovascular procedures for vessel occlusion is explained. In this context, particular attention is given to the treatment of peripheral AVM and those in the head and neck region.

Delayed and incomplete treatment may result in dural fistula development in children with Vein of Galen malformation

The association of dural arteriovenous fistulas (DAVF) in children with Vein of Galen malformation (VGM) has recently been reported for the first time. In a larger series of cases treated with transarterial NBCA embolization, 30% had DAVF. We wanted to analyze the development of DAVF in our cohort of children with VGM and to evaluate whether their occurrence depends on different treatment timing and embolic materials. We analyzed 43 VGM cases treated with a combined transarterial and transvenous approach between 2003 and 2016. In our early series until 2011, we used coils solely in 21 children. Since 2012, 22 children were treated with the combination of coils and Onyx. In the early series treated with coils solely, no case presented initially with or developed DAVF over time on follow-up angiograms. In our recent series we found four cases (9%) with DAVF. In two patients (5%), DAVF were found on the initial angiogram. Both patients presented at our department at age >2 years and were not treated elsewhere before. One patient (2%) presented at our department with too proximal occlusion of arterial feeders performed at another institution before. Only one patient (2%) developed DAVF in our department after the transarterial use of Onyx. Interestingly, this child did not develop DAVF as long as we used coils solely and his DAVF was localized exactly where an Onyx cast was identified. In conclusion, delayed and incomplete treatment may have a considerable impact on the occurrence of DAVF in VGM.

Caroli Disease Associated With Vein of Galen Malformation in a Male Child

We report the first case of a male child with both Caroli disease and vein of Galen malformation. The neonate presented to our department with congestive heart failure as a result of the intracranial arteriovenous high-flow shunt. Over time, several endovascular embolizations led to a complete angiographic occlusion of the shunt. Additionally, the diagnosis of Caroli disease was made at the age of 2 months. He developed choledocholithiasis necessitating endoscopic sphincterotomy and stone extraction. As a prolonged medical treatment he received ursodeoxycholic acid and antibiotics. A coincidence of Caroli disease and vein of Galen malformation has not yet been described. Both diseases are very rare, leading to the question of whether there is a link in the pathogenesis. Based on the few previously described underlying mechanisms, we develop hypotheses about the relationship between both rare diseases. We consider overexpression of vascular endothelial growth factor and its receptors as a possible common molecular mechanism in their pathogenesis. We also highlight the critical role of increased expression of the Notch ligand Jagged 1 both in the development of cerebral arteriovenous malformations in general and in the formation of dilated intrahepatic bile ducts (eg, in Caroli disease).

Non-enhanced MR imaging for preinterventional assessment of the angioarchitecture in vein of Galen malformations

Background and purpose Endovascular treatment of vein of Galen malformations (VGMs) requires sufficient preceding MR imaging. Standardized, preinterventional, non-invasive imaging has not been established. Our study is the first to examine the role of a dedicated, standardized, non-invasive imaging protocol in the evaluation of VGM angioarchitecture by non-contrast MRI/MR angiography. Materials and methods We retrospectively evaluated a consecutive series of VGM patients who underwent a 1.5 T MRI protocol, including standard T2 weighted images (T2WI), arterial time of flight (TOF), and thin T2WI without flow compensation (T2OffPh). The primary outcome was the proportion of patients in whom VGM subtypes and all arterial feeders (anterior (AChA) and posterior (PChA) choroidal arteries, pericallosal arteries, basilar tip, and leptomeningeal supply) could be accurately identified compared with a DSA gold standard. Results A total of 26 VGM patients who underwent 108 studies were used in the statistical analysis. VGM subtype was best seen in axial T2OffPh (92.1%) and TOF (89.8%). AChA feeders were best seen in TOF (86.5%) and axial T2OffPh (72.2%). PChA feeders were best seen in TOF (95.1%) and axial T2OffPh (88.1%). Pericallosal feeders were best seen in axial T2OffPh (95.4%) and TOF (95.1%). Basilar tip feeders were best seen in TOF (90.6%) and axial T2OffPh (88.4%). Conclusion VGM angioarchitecture is best seen in TOF and axial T2OffPh. It can be used as an alternative to global angiographic series.