An unusual pterygopalatine meningocele associated with neurofibromatosis Type 1 - Case report

The authors describe an unusual meningocele of the lateral wall of the cave rnous sinus and the anterior skull base in a young patient with typical sti gmata of neurofibromatosis Type 1 (NF1). This lesion was discovered during evaluation for recurrent meningitis. It represented an anterior continuatio n of Meckel's cave into a large cerebrospinal fluid space within the latera l wall of the cavernous sinus, extending extracranially through an enlarged superior orbital fissure into the pterygopalatine fossa adjacent to the na sal cavity. It was successfully obliterated, via an intradural middle fossa approach, with fat packing and fenestration into the subarachnoid space. T his meningocele most likely represents a variant of cranial nerve dural ect asia occasionally seen in individuals with NF1. It has as its basis the sam e mesodermal defect responsible for the more common sphenoid wing dysplasia and spinal dural ectasias identified with this condition. Involvement of t he trigeminal nerve with expansion of the lateral wall of cavernous sinus h as not been reported previously. The authors surmise, however, that it may be present in some cases of orbital meningocele associated with sphenoid wi ng dysplasia.