To evaluate the correlation between clinical manifestation of patients with nasolacrimal duct obstruction and pathological characteristics of lacrimal sac and dacryolith found during endoscopic dacryocystorhinostomy.

This retrospective study included 158 patients (189 eyes) who received endoscopic dacryocystorhinostomy. We defined lacrimal dacryolith by gross discovery in the lacrimal sac during surgery or findings during pathological examination as dacryolith or calcification, including size and distribution in pathology slides. We correlated the relationship between the patients' clinical manifestations, surgical results, lacrimal sac's pathological findings including calcification, inflammation and fibrosis, and pathological findings of lacrimal sac dacryolith.

Dacryolith was found in 61 eyes (32.3%) and among them, grossly found in 13 eyes (6.9%). Dacryolith's filling defect on dacryocystography was found in 17 eyes (9.0%) and based on grossly found dacryolith, dacryocystography's sensitivity and specificity were 58.8% and 1.7%, respectively. The average size of dacryolith was 0.3 ± 0.8 mm² with an average distribution of 20.1 ± 17.9%. Distribution of dacryolith and the proportions of inflammatory cells and fibrosis in the lacrimal sac were negatively correlated ( p < 0.05). The size of dacryolith and the proportions of fibrosis in the lacrimal sac were also negatively correlated ( p = 0.008). In cases where the proportion of calcification in pathology slides was over 50%, the duration of symptoms in the calcification-dominant group was shorter than in other groups ( p = 0.006). The success rates of endoscopic dacryocystorhinostomy with dacryolith and without dacryolith were 91.8% and 80.5%, respectively ( p = 0.046).

The patients with lacrimal sac dacryolith in nasolacrimal duct obstruction showed shorter duration of symptoms, lower fibrosis of lacrimal sac, and higher surgical success rates than the other cases. Therefore, additional research may be necessary to determine the mechanism of dacryolith formation and early treatment in nasolacrimal duct obstruction with lacrimal sac dacryolith.