In vivo biomicroscopy and photography of meibomian glands in a rabbit model of meibomian gland dysfunction.

The usefulness of transillumination and biomicroscopy of the lid margin in assessing meibomian gland dysfunction was studied in a rabbit model. Transillumination of rabbit lids treated with topical epinephrine for 2 to 3 months revealed plugging of the meibomian gland orifice. Plugging appeared to be correlated histopathologically with increased thickness and hyperkeratinization of the ductal epithelium at the orifice. Continued treatment resulted in microcystic changes within the duct, which were not easily discernible by routine examination without the aid of a transilluminator. Cystic changes were correlated with dilation of the duct by retained desquamated cornified cells. Biomicroscopy proved valuable in identifying and documenting early lesions associated with epinephrine-induced meibomian gland dysfunction.