ABSTRACT
The skin of the eyelids is thin with no subcutaneous fat. The eyelashes (14) line the edge of each lid to prevent dust entering the eye. Like all hairs they have sebaceous glands alongside. These may become infected and form a ‘sty’. Orbicularis oculi underlies the skin. It has an orbital part (15) that encircles the orbit to screw the eyes tightly shut, and a palpebral part (16) in the eyelids for blinking and keeping the eyelids opposed to the eyeball. The latter action is essential for correct function of the lacrimal mechanism; should the muscle or its nerve supply (VII) be injured the lid may fall away from the eye. Tears will then run down the face, possibly leaving the cornea dry and susceptible to ulceration.
