Focal, transient mechanical narrowing of a pipeline embolization device following treatment of an internal carotid artery aneurysm.

Flow diversion is a promising technique for cerebral aneurysm treatment but presents new and sometimes unique challenges. Transient reversible narrowing due to device reconfiguration of the pipeline embolization device (PED) has not been previously described. Here we describe a patient with dolichoectasia of the distal right internal carotid artery with an associated saccular sidewall aneurysm who developed asymptomatic circumferential narrowing of the proximal aspect of the PED in the first month following deployment. The patient was followed conservatively and demonstrated partial resolution of device narrowing on 6 month follow-up imaging.