Multifocal corneal argyrosis after an explosion injury

To document the clinical and histopathologic corneal features of a patient who developed multifocal corneal argyrosis after a chemical explosion injury with unusual involvement of the corneal stroma and keratocytes.

The corneal button was investigated by light and transmission electron microscopy and scanning electron microscopy combined with energy-dispersive x-ray microanalysis.

Clinically, the patient showed dark discoloration of the lids, periocular skin, episclera, and conjunctiva and had multiple brown dots in the superficial layers of the cornea. Microscopic examination of the cornea showed diffuse deposition of silver particles in the epithelial basement membrane, Bowman's layer, and Descemet's membrane. In the corneal stroma, silver granules accumulated intracellularly within lysosomal structures of degenerative keratocytes and extracellularly in association with collagen fibers and cellular debris. Energy-dispersive x-ray analysis showed peaks of silver and sulfur.

The toxic influence of intracellular accumulation of silver in stromal keratocytes may lead to cell damage and necrosis and result in visual impairment.