Optic Neuropathy in Chronic Intracranial Hypotension with Bony Remodeling

Bony remodeling of the orbit and sphenoid sinus with chronic intracranial hypotension has been described. The sphenoid sinus has been observed to enlarge with intracranial hypotension, sometimes leaving the optic canal completely surrounded by air. This; radiographic finding also occurs in a condition called sphenoid pneumosinus dilatans (SPD). While many cases of idiopathic SPD come to attention because of optic neuropathy, the presence or development of optic neuropathy in severe intracranial hypotension has not been closely examined.