“…The existing surgical methods include lacrimal intubation, YAG laser , external dacryocystorhinostomy (Ex-DCR) and EE-DCR [3][4]. For more than 100 years, Ex-DCR has been regarded as the "gold standard" for the treatment of chronic dacryocystitis, but it can't meet people's growing medical needs due to the shortcomings of facial skin scar, large trauma, affecting the function of "tear pump" and unable to deal with nasal complications at the same time [5][6][7]. Over the past 10 years, with the continuous improvement of endoscopic imaging system, ENT micro power system and other medical equipment, EE-DCR is highly recommended in clinic because of its incomparable advantages of Ex-DCR, such as no facial skin incision, minimally invasive and does not affect the function of "tear pump", simultaneous treatment of nasal complications, et al However, so far, the e cacy of EE-DCR has been reported differently, and its losers are not rare [8][9][10].…”