An elderly man presents with painful, redness of the right eye with medial canthal fullness and purulent discharge. CT orbit reveals a well-defined cystic lesion in the superomedial quadrant with scalloping of the adjacent orbital wall. The MOST likely diagnosis is:

• A Orbital cellulitis
• B Dermoid cyst
• C Capillary hemangioma
• D Mucocele of the frontal/ethmoid sinus ✓

Explanation

A mucocele is an expanding mucus-filled cyst arising from paranasal sinuses (most commonly frontoethmoid junction) that erodes into the orbit, producing superomedial displacement of the globe and bony remodeling/scalloping on CT. Orbital cellulitis causes diffuse proptosis with inflammatory fat stranding and no discrete cyst. Dermoid cysts are well-defined cysts with fat density on CT, typically at sutural lines (zygomaticofrontal), without sinus connection or scalloping. Capillary hemangiomas occur in infants and show enhancement, not cystic content.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.