The objective of this study is to further establish that SQUID, an alternative liquid embolic agent with specific properties, is a safe and effective alternative in bAVM endovascular treatment strategy available to date. Therefore, the performance of SQUID will be documented and its safety of use will be confirmed in current practice.

Inclusion Criteria:

• Patient planned for one or multiple embolization sessions using SQUID to achieve occlusion of a previously untreated bAVM.*

  *Patients with a direct fistula or saccular/flow-related aneurysm previously treated with NBCA and/or coils may be included.

• Patient in whom the use of SQUID had been decided for an embolization alone or in association to neurosurgery or radiotherapy.

• Patient ≥18 years old.

• Patient or authorized representative dully informed and having no objection to the clinical data collection and medical file access. An informed consent form must be signed and dated whenever required by local legislation

Exclusion Criteria:

• Patient with bAVM not eligible for endovascular treatment.

• Patient with bAVM previously treated by embolization with other devices (Liquid embolic agent, NBCA, particles, and coils).*

  *Patients with a direct fistula or saccular / flow-related aneurysm previously treated with NBCA and/or coils may be included.

• Patient with bAVM previously treated with surgery or radiotherapy.

• Patient intended to undergo surgery and embolization during the same procedure at first embolization

• Patient with multiple bAVM or bAVM associated with dural arteriovenous Fistula*.

  *Patients with a direct fistula or saccular / flow-related aneurysm previously treated with NBCA and/or coils may be included.

• Patient presenting contra-indication to the use of SQUID according to the Instructions For Use.

• Intention to treat with any non-adhesive embolic liquid other than SQUID, or planned treatment with another non-adhesive embolic liquid over the course of the endovascular treatment phase.

• Patient planned for a total endovascular treatment phase duration exceeding 2 years.

• Patient participating in another clinical study evaluating another medical device, another procedure or a medication.

• Any condition or any situation that would prohibit the patient from coming to the investigational center for the follow-up as recommended by the study protocol between 3 and 6 months, or prohibit carrying out the telephone mRS assessments at 1 month after each embolization session and at 12 months after the end of the endovascular treatment phase.

Consecutive patients planned for embolization using SQUID to achieve occlusion of a previously untreated bAVM.