Functional nasolacrimal duct decompression for chronic dacryocystitis

To investigate the feasibility of endoscopic nasolacrimal decompression for chronic dacryocystitis. 22 patients with chronic dacryocystitis hospitalized at Longgang ENT hospital were participated in this study. An injection of 30% iohexol was administered to conduct lacrimal sac angiography. The injection was stopped when the agent reflux from the lacrimal duct, and a computed tomography（CT） scan of the lacrimal duct was performed immediately. Sinuses Trachea Isoftware was used to reconstruct a three-dimensional（3D） view of the lacrimal passage and its surrounding structures. The software was used to simulate the "cutting" of the lacrimal sac and nasolacrimal duct; the lacrimal sac and nasal lacrimal duct were removed after 1/2-3/4 circumferences to decompress the passage and expose the membranous nasolacrimal duct. CT scans were performed on ten adult frozen cadaveric heads, and the nasolacrimal duct decompression operation was simulated. Then, the bone of the nasolacrimal duct was removed, membranous nasola