Floppy eyelid syndrome associated with Demodex Brevis

Six male patients with the floppy eyelid syndrome are described. They were successfully treated by lateral shortening of their eyelids. The excised eyelid blocks were histologically examined. In five of the six cases, the Meibomian glands were infested by the mite Demodex brevis. When compared with 20 randomly selected eyelid blocks, the incidence of Demodex brevis in the floppy eyelids was statistically significantly high (p< 0.01). These findings suggest a role of Demodex brevis in the pathogenesis of the floppy eyelid syndrome. Such a role has not been recognized before.