title: Tear film osmolarity in epiphora.
abstract: OBJECTIVE
  To examine whether patients complaining of epiphora have tears of a lower osmolarity.
  
  
  METHODS
  Sixty-three eyes of 39 patients attending an oculoplastic clinic with a primary complaint of epiphora, had their tear osmolarity recorded. Subjects were excluded if they had current or recent topical eye therapy, active ocular infection or allergy, ocular surface scarring, evidence of dry eye, previous laser eye surgery, or a contact lens worn within the previous 12 hours. Patients were divided into 2 groups. The first included those whose primary complaint was of epiphora due to either punctal stenosis, nasolacrimal duct obstruction (partial or complete), or eyelid laxity (without evidence of frank ectropion or entropion). The second group formed the controls, and consisted of the second eye of some of the above patients, or those attending the clinic for other oculoplastic procedures not related to epiphora. Testing of tear osmolarity was performed in the clinic using the TearLab osmometer.
  
  
  RESULTS
  Sixty-three readings were obtained, of which 32 were from patients with a primary complaint of epiphora and 31 were allocated to the control group. Patients with epiphora had a mean tear osmolarity of 291.8 mOsms/l (range, 269-324, standard deviation 16.6), compared with the control group mean of 303.7 mOsms/l (range, 269-354, standard deviation 24.1). This difference was found to be statistically significant (p = 0.025).
  
  
  CONCLUSIONS
  Patients complaining of epiphora in the absence of other ocular surface pathology have a significantly lower tear osmolarity.
authors: Oculoplastics, Moorfields Eye Hospital, Bedford, United Kingdom. george.saleh@moorfields.nhs.uk
authors: George M
authors: GM
authors: Saleh
authors: Badrul
authors: B
authors: Hussain
authors: Simon A
authors: SA
authors: Woodruff
authors: Anant
authors: A
authors: Sharma
authors: Andre S
authors: AS
authors: Litwin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015352:Dry Eye Syndromes / Q000175:diagnosis; D005260:Female; D006801:Humans; D007766:Lacrimal Apparatus Diseases / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D061286:Osmometry; D013666:Tears / Q000737:chemistry*