The method of delivering an implant in an intracranial vessel includes deploying an anchor of a tethering device in an anchoring vessel forming a first fixation point and advancing a guide-sheath to a location near the anchoring vessel. The tethering device has a tether extending proximally from the anchor and the guide-sheath has at least one lumen. The method includes attaching the guide-sheath to the tether of the tethering device forming a second fixation point proximal to the first fixation point, delivering an implant through the lumen of the guide-sheath towards a treatment site distal to the first fixation point and located within an intracranial vessel, and deploying the implant at the treatment site. Related devices, systems, and methods are also provided.
