Temporal lobe encephalocele appearing as a lytic lesion of the skull base and pterygoid process.

Meningoencephalocele is an uncommon condition in which brain tissue, meninges, or both protrude through a defect in the anterior cranial fossa and into the ethmoid sinus or nasal cavity. Much less often, brain tissue, meninges, or both protrude through a defect in the middle cranial fossa and into the sphenoid sinus. We report an unusual case of a middle fossa encephalocele that appeared as a lytic lesion of the skull base. The patient was treated successfully via a unique endoscopic transpterygoid approach--that is, an endoscopic approach through the maxillary sinus and pterygopalatine fossa and into the pterygoid process.