Lacrimal sac diverticulum presenting as a lower eyelid mass with a secreting fistula.

Lacrimal sac diverticula are outpouchings of the lacrimal sac. Their various clinical symptoms complicate differential diagnosis. Here we report two patients of distinctive type of lacrimal sac diverticula. Each of them presented with a mass inferior to the medial canthus with a secreting fistula. Irrigation demonstrated lacrimal drainage system patency. The orificium fistula was located at lower palpebral conjunctiva. This distinctive type of lacrimal diverticulum had never been reported in the literature as we know. The mass had no apparent connection with lacrimal sac according to the results of computed tomography dacryocystography and B-scan ultrasonography. All patients underwent surgical exploration and mass removal under general anesthesia. The mass was confirmed as lacrimal sac diverticulum by pathological examination.