Incidence of acquired lacrimal drainage system obstruction in epiphoric patients in Thailand

Background: There were few reports regarding the incidence of the acquired nasolacrimal duct obstruction, and the incidence in different geography or countries might be alike. Since the nasolacrimal drainage system obstruction is a common problem in Thailand, knowledge of the incidence may disclose the burden of the disease that has never been reported. Objectives: Evaluate the incidence of acquired lacrimal drainage system obstruction (ALDO) in Thailand. Methods: This study was conducted in multi-centers. It was based on prospective and descriptive design. All patients with epiphoric symptoms visiting the outpatient departments of five tertiary eyecare centers were recruited between 2004 and 2007. Features of epiphoric symptoms and medical history were recorded, and complete ophthalmic examinations were performed. Results: Epiphoric patients were enrolled from all medical centers with 245 eligible patients, female:male ratio was 4.2:1. Ninety-nine patients (40%) had duration of epiphoric symptoms between one-five years. ALDO was found in 111 patients (45%) with female preponderance (6.9:1). Seventy-one patients (64%) had pre-sac obstruction and 40 patients (36%) had post-sac obstruction. Among other causes of epiphora, dry eye was the most common. Conclusion: The most common cause of epiphora was ALDO. The four-year incidence rate of ALDO among epiphoric patients was 45%.