Optic Nerve Sheath Meningocele Diagnosed in Patients with Exophthalmos

ABSTRACT

Purpose@#To report a rare case of bilateral optic nerve sheath meningocele diagnosed in a patient with exophthalmos.Case summary: A 33-year-old male visited our clinic with bilateral exophthalmos for 6 months. The patient had been diagnosed with hypertension 3 years previously; however, the condition had been poorly controlled. He also had a history of treatment associated with retinal vein occlusion, macular edema, and papilledema 2 years earlier. There was no limitation in his ocular movement. A Hertel exophthalmometry test showed bilateral exophthalmos of 20 mm in both eyes. Visual field tests showed an inferior arcuate visual field defect in the right eye and a superotemporal peripheral field defect in the left eye. In orbital magnetic resonance imagery, cerebrospinal fluid space widening along the optic nerve and flattening of the bilateral posterior pole of the eye were evident. The patient was diagnosed with optic nerve sheath meningocele. @*Conclusions@#Optic nerve sheath meningocele should be considered as a differential diagnosis of exophthalmos patients. Because it is a disease that can affect visual function in a manner similar to that of a visual field defect, rapid diagnosis through imaging study and thorough regular follow-up examinations are essential.