CONGENITAL NASOLACRIMAL DUCT OBSTRUCTION - NATURAL-HISTORY AND THE TIMING OF OPTIMAL INTERVENTION

Nasolacrimal duct obstruction (NLDO) is a relatively common clinical p roblem. Debate continues about optimal management. Intervening early a nd intervening late each have advantages and disadvantages. We reviewe d the world literature on NLDO. We assembled information on occurrence , natural history, and results of treatment. Spontaneous remission dat a were used to derive the probability of continued obstruction versus age. The prevalence a hypothesized treatment-resistant form of NLDO wa s estimated. Symptomatic NLDO probably occurs in 5 to 6% of infants. G iven a symptomatic case under the age of 14 months, the probability to spontaneous remission within the following month appears to be approx imately one of three. Probe failure risk increases with age, doubling every 6 months. Increasing probe failure risk may be due to self-selec tion. Preliminary analysis of management strategies suggests that lacr imal duct probing at age 4 months in the office is the most cost-effec tive strategy. Further descriptive studies of NLDO remission and treat ment are indicated.