Adrenaline dacryolith: detection by ultrasound examination of the nasolacrimal duct

A 73-year-old woman on topical pilocarpine and adrenaline for chronic simple glaucoma for three years presented with a mass in the medial canthus of the right eye. Although dacryocystography showed a dilated and partially obstructed nasolacrimal system, ultrasound examination was able to demonstrate a mass in the nasolacrimal duct. At operation a black dacryolith was found, of the diameter predicted by ultrasound. Histological examination of the dacryolith suggested its derivation from breakdown products of adrenaline.