Dmitry Kislitsin

Intraorbital arteriovenous fistulas are rare arteriovenous shunts inside the orbit without connection with the cavernous sinus. This article describes a clinical case of multiple metachronous intraorbital arteriovenous shunts in a patient with univentricular heart disease and secondary erythrocytosis. Transarterial embolization of the first shunt had a positive clinical effect for 2 months. The recurrence of symptoms was caused by the formation of a new shunt on the same draining vein, but in a place remote from the previous locus. Repeated embolization gave a positive effect for the same period. The next relapse had a more malignant course, up to dislocation of the eyeball. The right orbit decompression has given a stable positive clinical effect up to the present moment. Based on extremely limited literature data of such cases and our own experience, we concluded that an individual and multidisciplinary approach to such patients with careful postoperative follow-up is necessary.

Numerical modeling is an effective tool for preoperative planning. The present work is devoted to a retrospective analysis of neurosurgical treatments for the occlusion of cerebral aneurysms using flow-diverters and hemodynamic factors affecting stent endothelization. Several different geometric approaches have been considered for virtual flow-diverters deployment. A comparative analysis of hemodynamic parameters as a result of computational modeling has been carried out basing on the four clinical cases: one successful treatment, one with no occlusion and two with in stent stenosis. For the first time, a quantitative assessment of both: the limiting magnitude of shear stresses that are necessary for the occurrence of in stent stenosis (MaxWSS > 1.23) and for conditions in which endothelialization is insufficiently active and occlusion of the cervical part of the aneurysm does not occur (MaxWSS < 1.68)—has been statistacally proven (p < 0.01).

The necessity of quick surgical treatment of acute ruptured cerebral aneurysms was demonstrated in large studies by the ISAT and ISUIA, which also proved the advantage of the endovascular method over the surgical one. Ballonassistence is widely used in treatment of aneurysms with wide neck and unfavorable vascular anatomy, but the radicality of the treatment is insufficient. The aim of this study was to demonstrate the efficacy and safety of stent-assisted embolization of «acute» cerebral aneurysms. Material and methods. A retrospective analysis of the treatment of 234 patients with «acute» cerebral aneurysms was carried out. Results. Only coils were used in 40.6 % of cases (n = 95), balloon-assistance, in 40.2 % of cases (n = 94), and stent-assistance, in 19.2 % of cases (n = 45). There were 11.5 % (n = 27) clinically significant complications. Total aneurysm occlusion (Raymond-Roy I) was achieved in 187 cases (79.9 %); the radicality at the control examination was 67.1 % (157 patients). Discussion. The radicality of the treatment with stents was slightly higher then with balloons and coils at the end of operation (84.4 %, n = 38 and 78.8 %, n = 149, p > 0.05), but it was significantly higher at the control examination (80.0 %, n = 36 and 60.8 %, n = 115, respectively, p Conclusions. Intracranial stents allow achieving good results of the embolization of complex aneurysms in the acute period of intracranial hemorrhage without increasing the risk of surgical treatment.

Introduction The endovascular stent-assisted coiling approach for the treatment of cerebral aneurysms is evolving rapidly with the availability of new stent devices. It remains unknown how each type of stent affects the safety and efficacy of the stent-coiling procedure. Methods This study compared the outcomes of endovascular coiling of cerebral aneurysms using Neuroform (NEU), Enterprise (EP), and Low-profile Visualized Intraluminal Support (LVIS) stents. Patient characteristics, treatment details and angiographic results using the Raymond–Roy grade scale (RRGS), and procedural complications were analyzed in our study. Results Our study included 659 patients with 670 cerebral aneurysms treated with stent-assisted coiling (NEU, n=182; EP, n=158; LVIS, n=330) that were retrospectively collected from six academic centers. Patient characteristics included mean age 56.3±12.1 years old, female prevalence 73.9%, and aneurysm rupture on initial presentation of 18.8%. We found differences in complete occlusion on baseline imaging, defined as RRGS I, among the three stents: LVIS 64.4%, 210/326; NEU 56.2%, 95/169; EP 47.6%, 68/143; P=0.008. The difference of complete occlusion on 10.5 months (mean) and 8 months (median) angiographic follow-up remained significant: LVIS 84%, 251/299; NEU 78%, 117/150; EP 67%, 83/123; P=0.004. There were 7% (47/670) intra-procedural complications and 11.5% (73/632) post-procedural-related complications in our cohort. Furthermore, procedure-related complications were higher in the braided-stents vs laser-cut, P=0.002. Conclusions There was a great variability in techniques and choice of stent type for stent-assisted coiling among the participating centers. The type of stent was associated with immediate and long-term angiographic outcomes. Randomized prospective trials comparing the different types of stents are warranted.

Background Intracranial aneurysms located in the distal vessels are rare and remain a challenge to treat through surgical or endovascular interventions. Objective To describe a multicenter approach with flow diversion using the pipeline embolization device (PED) for treatment of distal intracranial aneurysms. Methods Cases of distal intracranial aneurysms defined as starting on or beyond the A2 anterior cerebral artery, M2 middle cerebral artery, and P2 posterior cerebral artery segments were included in the final analysis. Results 65 patients with distal aneurysms treated with the PED were analyzed. Median aneurysm size at the largest diameter was 7.0 mm, 60% were of a saccular morphology, and 9/65 (13.8%) patients presented in the setting of acute rupture. Angiographic follow-up data were available for 53 patients, with a median follow-up time of 6 months: 44/53 (83%) aneurysms showed complete obliteration, 7/53 (13.2%) showed reduced filling, and 2/53 (3%) showed persistent filling. There was no association between patient characteristics, including aneurysm size (P=0.36), parent vessel diameter (P=0.27), location (P=0.81), morphology (P=0.63), ruptured status on admission (P=0.57), or evidence of angiographic occlusion at the end of the embolization procedure (P=0.49). Clinical outcome data were available for 60/65 patients: 95% (57/60) had good clinical outcome (modified Rankin Scale score of 0–2) at 3 months. Conclusions This large multicenter study of patients with A2, M2, and P2 distal aneurysms treated with the PED showed that flow diversion may be an effective treatment approach for this rare type of vascular pathology. The procedural compilation rate of 7.7% indicates the need for further studies as the flow diversion technology constantly evolves.

Background: Precipitating hydrophobic injectable liquid is a newly introduced liquid embolic agent for endovascular embolization with some technical advantages over other liquid embolic agents. We present our initial experience with precipitating hydrophobic injectable liquid in the endovascular treatment of cerebral arteriovenous malformations. Methods: From October 2015 to January 2018, 27 patients harboring cerebral arteriovenous malformations underwent endovascular embolization with precipitating hydrophobic injectable liquid 25. Clinical features, angiographic results, procedural details, complications, and follow-up details were retrospectively analyzed. Results: Twenty-seven patients with cerebral arteriovenous malformations were included. Total obliteration in one endovascular session was confirmed for 14/27 (52%) patients. Partial embolization was attained in 13 patients (48%) in whom staged treatment with following radiosurgery or surgery was planned. No mortality was recorded in this series. Complications during or after the embolization occurred in six of 27 (22.2%) patients. Conclusion: In our initial experience, precipitating hydrophobic injectable liquid has acceptable clinical outcome comparable to other liquid embolic agents. Although this is the largest reported study in arteriovenous malformation treatment with precipitating hydrophobic injectable liquid, further studies are needed to validate its safety and efficacy.

Utilization of flow diverting devices is accompanied with dual antiplatelet therapy to reduce the risk of thromboembolic events, even though this increases the risk of hemorrhagic complications. The updated Pipeline Flex embolization device with Shield Technology has been created using a phosphorylcholine coating that reduces thrombogenicity and possibly reduces the need for dual antiplatelet therapy. However, because of the potential risk to patients of utilizing a pipeline embolization device without dual antiplatelet therapy, the pipeline embolization device with Shield Technology has not been tested in human subjects without dual antiplatelet therapy, and its contribution to preventing thromboembolic events is therefore unknown. We report a case in which a patient, following complications that limited his absorption of dual antiplatelet therapy, had low levels of dual antiplatelet therapy medications in his bloodstream following treatment for an intracranial aneurysm with a pipeline embolization device with Shield Technology. The patient recovered without signs of luminal stenosis or thromboembolic event.

Superselective transvenous embolization (TVE) with liquid embolic agents is a new concept in treatment of vein of Galen aneurysmal malformations (VGAM). We performed ten sessions of TVE in VGAM patients with restricted transarterial access. In this paper, we assessed clinical and angiographic outcomes of the proposed treatment and discussed three different TVE techniques with regard to morphology of the shunt and outflow tract. Safety and avoidance-of-complication tips were also discussed.