Large Paranasal Cyst Severely Compressing the Extraocular Muscles and the Optic Nerve Without Any Visual Symptoms

Large sinus cysts often present with ocular symptoms, including visual disturbance and diplopia. We present the case of an 80-year-old woman with a large paranasal cyst that had protruded into the cranium and orbit, compressing the extraocular muscles and optic nerve. Despite these findings, the patient reported no symptoms. She had endoscopic sinus surgery and the cyst was found to contain ochreous, cholesterol-like contents. The reason for this paradoxical situation is that the enlargement was slow and gradual, causing no damage to the visual organs. However, once sudden changes occur, such as an infection, severe visual symptoms may develop.