AbstractBackgroundThe most common treatment for congenital lacrimal duct obstruction is standard probing without dacryoendoscopy. However, the lacrimal duct cannot be observed in this procedure. If the probing procedure allows the observation of the lacrimal duct, it could be more successful and safer. To use endoscopic probing to view the lacrimal duct in cases of congenital lacrimal duct obstruction 6 months post‐surgery and to evaluate the condition of the lumen while simultaneously performing direct endoscopic probing.DesignThis is a retrospective, non‐comparative case series.ParticipantsThe study participants were 10 children aged 14–74 months, including three children with bilateral obstruction. In total, 13 congenital lacrimal duct obstruction were probed.MethodsThe patients underwent direct endoscopic probing with dacryoendoscopy instead of blind probing, that is, standard probing without dacryoendoscopy under brief total anaesthesia.Main Outcome MeasuresDuring the procedure, outcomes were assessed as the endoscope reached the nasal cavity. A successful probing outcome was defined as an absence of tearing and discharge.ResultsTwelve congenital lacrimal duct obstruction were successfully treated by direct endoscopy, whereas one was not. There were various sites of obstruction and various conditions such as oedematous thickening of the mucosa of the lacrimal duct and fibrous tissue because of chronic inflammation. The subjective outcome from their parents by telephonic interview was obtained. Epiphora disappeared in 12/13 (92.3%) of the eyes treated by endoscopy; however, 5/13 (38.5%) of the patients reported occasional discharge from the eyes.ConclusionsDirect endoscopic probing is effective and safe to treat cases of congenital lacrimal duct obstruction in children.