Floppy eyelid, an under-diagnosed syndrome: a review of demographics, pathogenesis, and treatment.

Floppy eyelid syndrome (FES) is a frequent eyelid disorder characterized by eyelid laxity that determines a spontaneous eyelid eversion during sleep associated with chronic papillary conjunctivitis and systemic diseases. FES is an under-diagnosed syndrome for the inaccuracy of definition and the lack of diagnostic criteria. Eyelid laxity can result from a number of involutional, local, and systemic diseases. Thus, it is pivotal to use the right terminology. When the increased distractibility of the upper or lower eyelid is an isolated condition, it is defined as 'lax eyelid condition' (LAC). When laxity is associated with ocular surface disorder such as papillary conjunctivitis and dry eyes, it can be referred to as 'lax eyelid syndrome' (LES). However, FES is characterized by the finding of a very loose upper eyelid which everts very easily and papillary tarsal conjunctivitis affecting a specific population of patients, typically male, of middle age and overweight. Obesity in middle-aged male is also recognized as the strongest risk factor in obstructive sleep apnea-hypopnea syndrome, (OSAHS). FES has been reported as the most frequent ocular disorder associated with OSAHS. Patients with FES often complain of non-pathognomonic ocular signs and symptoms such as pain, foreign body sensation, redness, photophobia, and lacrimation. Due to these clinical features, FES is often misdiagnosed while an early recognition might be important to avoid its chronic, distressing course and the associated morbidities. This review provides an updated overview on FES by describing the epidemiology, proposed pathogenesis, clinical manifestations, related ocular, and systemic diseases, and treatment options.