Background and Objectives: Primary acquired nasolacrimal duct obstruction (PANDO) is a common ocular problem. Clinical presentation can range from simple tearing to a life-threatening condition. The exact pathophysiology of obstruction is not completely understood. In this study, therelationship between PANDO and nasal mucosal goblet cells was investigated. 
Materials & Methods: In this case-control study, 15 subsequent patients with PANDO were enrolled. Patients were operated with endoscopic dacryocyctorhinostomy. A small piece of nasal mucosal biopsy sample was obtained from inferior turbinate. The samples were prepared and stained for mucin. Goblet cells were counted in the specimens. The results were compared with the nasal mucosa of 15 normal persons who were underwent rhinoplasty surgery as control group. Data were analyzed by SPSS version 16 software and were assessed using t-test, analysis of variance, and Pearson correlation test.
Results:In patients group, 13 cases (86.7%) were female and 2 cases (13.3%) were male. The mean age was 42.4±14.3 years (range, 23-68 years). In control group, 9 persons (60%) were female and 6 persons (40%) were male. The mean age was 35.5±12.1 (range, 19-58 years) (P>0.05). All patients had epiphora, and 66.7% of patients had purulent discharge. Duration of symptoms ranged from 1 year to 12 years. The number of goblet cells of the nasal mucosa in patient group was significantly higher than the control group (P<0.001). Inflammation was not related to goblet cell numbers
Conclusion: According to findings of this study, goblet cells have important role in inflammatory process and perhaps obstruction in nasolacrimal duct.