Obstructing encephaloceles presenting as chronic rhinosinusitis: lessons learned from a case series.

We present a unique anatomic cause of encephalocele, and describe appropriate diagnosis. Two patients underwent stereotactic image-guided sinus surgery for presumed chronic rhinosinusitis with intraoperative findings of a sinus encephalocele. The first patient underwent a conservative 2-stage management that included an initial cerebrospinal fluid (CSF) leak repair followed by encephalocele resection. The second patient underwent a 1-stage encephalocele resection and CSF leak repair with a septal graft. The sinus surgeon needs to consider the possibility of encephalocele when the ethmoid, sphenoid, or, rarely, frontal sinuses present with an isolated opacification that does not improve with conservative medical therapy.