To analyze postoperative CT dacryography features in patients with persistent epiphora after endonasal surgery.We conducted a retrospective study of 76 patients with a history of persistent epiphora after endonasal ENT surgery who underwent CT dacryography between January 2014 and February 2020. Volume acquisition of sub-millimeter sections allowed 2D and 3D reconstructions with virtual endoscopy of the nasosinusal cavities and the lacrimal canal.The postsurgical appearance of the nasosinusal cavities revealed a middle meatal antrostomy in 37% of cases, less frequently an ethmoidectomy or an inferior meatal antrostomy, sometimes completed by a middle or inferior turbinectomy. In thirty-five patients (46%), the lacrimal canal was distant from the endonasal ENT procedure. Epiphora was related to mucosal hypertrophy, constricting all or part of the lacrimal canal. Thirty-three patients (43%) showed changes in the lacrimal canal at the surgical site. In the inferior meatus, the nasolacrimal orifice was sometimes involved in the inferior turbinectomy or meatotomy, but most of the time, in the middle meatus, resection of the uncinate process prior to ethmoidectomy or middle meatotomy was associated with a lesion of the contiguous lacrimal canal.As a rare cause of persistent tearing, involvement of the nasolacrimal duct at the edge of the endonasal ENT surgery highlights the importance of intraoperative localization of the nasolacrimal duct before resection of the uncinate process or the inferior turbinate, ideally predicted by preoperative CT imaging.