title: Tear-Film Osmolarity Changes Following Dacryocystorhinostomy in Primary Acquired Nasolacrimal Duct Obstruction.
abstract: To evaluate tear osmolarity (TO) in patients with epiphora caused by primary-acquired nasolacrimal-duct obstruction (PANDO), before and after an external dacryocystorhinostomy (DCR) and to compare with healthy control subjects.
  
  
  
  Twenty eyes of 20 patients (15 women, 5 men) who suffered from epiphora for at least one year due to PANDO, and 20 eyes of 20 healthy subjects (13 women, 7 men), were included in this study. External DCR was applied to all patients with PANDO, and TO measurements were repeated during the first month follow-up visit after surgery.
  
  
  
  The mean period for complaints of epiphora was 1.7 ± 0.6 years (1-3). Patients had a mean TO of 282.6 ± 10 mOsm/l (range: 269-302) prior to DCR, and this increased to 297.7 ± 7.7 mOsm/l (range: 284-310) one month after DCR (p = 0.0001). Preoperative TO values were significantly lower when compared with the healthy control subjects' (301.7 ± 10.6 mOsm/l (range: 280-316) (p = 0.0001). No significant differences were detected between postoperative and control group TO values (p = 0.18).
  
  
  
  Epiphora due to PANDO causes lower TO values. One month after DCR, TO came to similar TO levels when compared to healthy subjects.
authors.affiliation: a Department of Ophthalmology , Ankara Ataturk Education and Research Hospital , Ankara , Turkey.
authors.forename: Nilay
authors.initials: N
authors.lastname: Yuksel
authors.affiliation: b Department of Ophthalmology , Yildirim Beyazit University, Ankara Ataturk Education and Research Hospital , Ankara , Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Akcay
authors.affiliation: a Department of Ophthalmology , Ankara Ataturk Education and Research Hospital , Ankara , Turkey.
authors.forename: Berna
authors.initials: B
authors.lastname: Ayan
authors.affiliation: c Department of Ophthalmology , Kayseri Education and Research Hospital , Kayseri , Turkey.
authors.forename: Necati
authors.initials: N
authors.lastname: Duru
mesh_terms: D000328:Adult; D003608:Dacryocystorhinostomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007767:Lacrimal Duct Obstruction / Q000175:diagnosis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009301:Nasolacrimal Duct / Q000378:metabolism / Q000601:surgery*; D009994:Osmolar Concentration; D011184:Postoperative Period; D013666:Tears / Q000737:chemistry*
keywords: Dacryocystorhinostomy; epiphora; tear osmolarity