Abstract:AIM:To analyze cases of obstruction of the nasolacrimal duct which creates a fertile environment for secondary bacterial infection and can result in dacryocystitis,which is a constant threat to cornea and orbital soft tissue and a potential source of endophthalmitis following intraocular surgery. The majority of obstructions of the lacrimal excretory outflow system are acquired ones occurring in adulthood and involving the distal parts of the system. Acquired obstruction may be primary/idiopathic or secondary to a wide variety of infectious, inflammatory, traumatic, mechanical, toxic or neoplastic causes mimicking idiopathic inflammation. These cases are treated by dacryocystorhinostomy (DCR).METHODS:The present study was conducted to determine the histopathologic, immunohistochemical and current microbiologic characteristics of lacrimal sac specimens in patients undergoing external dacryocystorhinostomy.RESULTS:Non-specific lacrimal sac pathology was present in all 33 cases and 81.8% of the cases showed moderate chronic inflammation with a chronic inflammatory score (CIS) ranging between 4 and 6, whereas 12.12% showed severe inflammatory changes with a CIS of 7. Mild degree of inflammation was seen in 6.06% with a CIS of 3. The total prevalence of gram-positive, gram-negative, and culture-negative samples were 59.4%, 37.5%, and 3% respectively.CONCLUSION:Non-specific chronic inflammation with fibrosis is indeed the most commonly reported histopathological finding in lacrimal sac wall biopsy specimens.