Orbital apex syndrome caused by ethmoid sinus mucocele: a case report and review of literature

Ethmoid sinus mucoceles are benign, expansile and cyst-like lesions, when sufficiently large, may causing compression of the optic nerve and nearby structures. We report an extremely rare case of ethmoid sinus mucocele causing orbital apex syndrome. A 59-year-old female presented with over one month history of left-side headache that worsened with left-side ophthalmodynia for six days, accompanied by left-side sudden ptosis and vision loss for half a day. Clinical findings were proved with that of a combined CN II, III, IV and VI paralysis. Computed tomographic scan demonstrated a dense homogeneous mass expanding the left ethmoid sinus and rarefaction of the lateral wall of the left ethmoid sinus with the contents compressing the optic nerve. She underwent a prompt endoscopic sinus surgery. Three days after the operation, the movement and vision of the left eye returned to normal, the left eye pain and headache had also resolved.