Prospective, Post-registration, Interventional, Randomized, in Parallel Groups, Multicenter Eurasian Clinical Study of DERIVO®/DERIVO® Mini Aneurysm Embolization Device, Europe-Asia

Inclusion Criteria: * localization and structure of the aneurysm allows the use of a DERIVO®/DERIVO® mini flow-diverting stent for treatment; * the aneurysm cannot be cured by other methods of endovascular therapy, or there is a higher risk of complications when using other methods of endovascular therapy or microsurgery; * clipping or embolization with spirals (if performed earlier) led to a recurrence of the aneurysm. Exclusion Criteria: 1. Age less than 18 years. 2. Pregnancy. 3. The presence of a previously implanted stent in a cerebral artery. 4. Dissection of cerebral or peripheral vessels. 5. The presence of contraindications to the use of the DERIVO®/DERIVO® mini medical device, specified in the instructions for use: * non-compliance of the aneurysm and/or the carrier vessel with the indications for the use of the device; * non-physiological structure of cerebral vessels; * vascular disorders that are a contraindication to endovascular interventions. 6. The presence of contraindications for antiplatelet (antithrombotic) and/or anticoagulant therapy in accordance with the instructions for the medical use of drugs.