Research on animal models of chronic dacryocystitis in dogs

Abstract Objective To explore an ideal animal model of chronic dacryocystitis. Methods (1) The anatomical structure of the lacrimal drainage system in dogs was observed; (2) The canine lacrimal drainage system was obstructed by cauterization of the nasolacrimal duct; (3) A canine model of dacryocystitis was established by combining nasolacrimal duct cauterization with inoculation of Staphylococcus aureus. Results Compared with inoculation of Staphylococcus aureus one week after nasolacrimal duct cauterization, the combined method of nasolacrimal duct cauterization and immediate inoculation of Staphylococcus aureus induced clinical manifestations of dacryocystitis more rapidly in dogs. The modeling success rate was 83.3%. Conclusion Our experimental data demonstrate that the anatomical structure of the canine lacrimal duct is similar to that of humans, providing a solid anatomical foundation for modeling chronic dacryocystitis. The method of nasolacrimal duct cauterization combined with Staphylococcus aureus injection can rapidly and effectively induce canine dacryocystitis manifestations while being simple and feasible to perform. Therefore, dogs can be considered as a suitable animal model for further research on chronic dacryocystitis. This model reliably reproduces key pathological features—including chronic inflammation, ductal obstruction, and bacterial persistence—enabling mechanistic studies and therapeutic evaluation. Its reproducibility and clinical relevance support translational applications in developing novel interventions for human chronic dacryocystitis. If a more persistent chronic inflammatory model is to be constructed, further optimization of surgical parameters and inoculation protocols will still be required.