A 46-year-old woman was admitted to hospital in March 2005 for a painful mass in the outer third of the left upper eyelid of 6 months' duration, accompanied by a decrease in ipsilateral visual acuity (VA). The patient reported the development of a similar mass 15 years prior to her admission, which was successfully managed with unspecified medical treatment. The rest of the history was not relevant to the current condition.
Ophthalmological examination revealed a VA of 0.7 in the right eye (OD) and 0.2 in the left eye (OI). In the outer third of the left upper eyelid there was a 4 ¥ 3.5 cm painful mass accompanied by ptosis, inferior displacement of the eyeball on the same side. There was a limitation to levosupraversion of the left eye. Exophthalmometry with base 100 was 17 mm for both eyes. The palpebral aperture was 10 mm in the OD and 4 mm in the OI. Left levator muscle function was limited.
A CT scan of both orbits with axial and coronal slices was requested and showed a cystic looking temporal mass with bony destruction, invading the orbit and displacing the left eyeball downwards, apparently dependent on the frontal sinus.
An aspiration of the mass was performed, from which a dense yellowish liquid was obtained. A smear of the contents showed few Gram-positive cocci in pairs and chains, accompanied by numerous polymorphonuclear leukocytes and abundant mucus. Treatment with oral ampicillin, dicloxacillin and naproxen and topical sulfacetamide was started.
The patient underwent drainage of the paranasal sinus contents with removal of the sinus wall. Microscopically, haematoxylin and eosin stained slides demonstrated fragments lined by respiratory-type epithelium. Below the epithelium, the wall consisted of a dense connective tissue stroma with areas of haemorrhage mixed with variable clusters of inflammatory infiltrate consisting of mature lymphocytes, plasma cells, polymorphonuclear leukocytes and numerous eosinophils. The diagnosis of frontal sinus mucocele was established. The presence of large numbers of eosinophils as part of the inflammatory infiltrate suggested a probable allergic or hypersensitivity etiology.