Aim: To establish prevalence of conjunctival concretions in a random cohort of patients visiting the generál outpatients' department of the Department of Ophthalmology of the Faculty Hospital and lst Medical faculty, Charles University in Prague, Czech republic. Cohort of patients and Methods: The cohort consisted of 500 consecutive patients, 190 males and 310 females visiting the generál outpatients' department with various problems. The mean age was 46.8 years (13-103 years). The complete eye examination, including detailed check-up of tarsal conjunctiva and conjunctiva of the fornices at the slit lamp was performed. The presence of conjunctival concretions, frequency of the foreign body sensation in patients with concretions, localization of the concretions and their structure, dependence of the concretions' presentation on the patienťs age, the dysfunction of the Meibomian glands, and chronic meibomitis were established. Results: The presence of the conjunctival concretions was found in 198 patients (39.6 %), symptomatic were 6 % of patients with deposits only. No significant difference was found between the localization on the upper and lower eye lid, nor right or left eye. Superficial deposits (85.8 %) were more common than the deep ones, hard deposits (79.8 %) more common than the gelatinous ones, and single deposits (77.8 %) more common than the confluent ones. Deposits were found in patients as early as at the age of 20 years, with the maximum of occurrence between 30-80 years of age. In 30.3 % of patients with conjunctival concretions, the dysfunction of Meibomian glands, or chronic meibomitis were detected. Summary: Frequent presence of conjunctival deposits in random cohort of patients was established, and occurrence in younger groups of patients was noticed. Symptomatic deposits were found in 6 % of patients only.

        Key words: conjunctival concretions, prevalence, chronic conjunctivitis, meibomitis