Evaluation of the results of endovascular treatment using agents containing ethylene vinyl alcohol copolymer in cerebrovascular malformations in pediatric patients

We included in our study the use of ethylene vinyl alcohol copolymer ("Squid") in our institution in the last decade. "and "Onyx"), we only included intraparenchymal AVM cases after excluding cerebrovascular malformations such as GVAM, pAVF, p&dAVF, pAVM, and DSM, which we treat endovascularly with Onyx. Among the 32 patients we found after scanning the hospital information management system, 9 patients were excluded due to non-AVM cerebrovascular malformation. Among the 23 patients, we excluded 2 patients because we did not have access to the squid agent at that time and treated them endovascularly with Onyx. We studied our findings on 21 patients in whom we used the squid agent. For low-risk patients, we used EVT as the primary therapy to achieve a definitive cure. For high-risk patients, we used a "non-aggressive" endovascular treatment algorithm that aimed to minimize procedural complications while reducing the degree of AVM with nidus embolization as much as possible. With this treatment algorithm, we achieved cure in 57.1% of our patients. Recurrence occurred in 33.3% of our patients. In addition to EVT, we achieved a cure rate of 89.4% with multimodality treatment using microsurgery in 14.3% and sRC in 46.5%. None of our patients developed procedure-related morbidity or mortality. This study was the first case series in the literature using squid, which has similar efficacy and safety rates to onyx in pediatric case series. In our study, 14.3% of patients used both the transvenous and transarterial routes, and 14.3% of patients used the double-lumen hypercompliant balloon (also known as the Eclipse 2L). In each of these instances, our study is one of the few case series in the literature that demonstrates the secure and effective application of both the transvenous route and the hypercompliant balloon. As a result, endovascular treatment using a squid liquid embolizing agent is an effective and safe treatment tool for pediatric cerebrovascular malformations that increases the likelihood of treatment success either as a cure alone or as a part of multimodal treatment.