Changes in tear flow accompanying aging

Am J Optom Physiol Opt. 1978 Feb;55(2):69-74. doi: 10.1097/00006324-197802000-00001.


The tear-turnover rate of 68 normal human subjects (age range 15-63 yr) was determined using a slit lamp modified to serve as a fluorophotometer. Tear volume and tear secretion, computed from tear-turnover rate, had mean values of 8.47 microliter and 1.78 microliter/min, respectively. Analysis of the results shows a decrease in tear production with age. The mean tear-flow rate was 1.55 microliter/min in subjects aged 15-39 and 0.95 microliter/min in subjects aged 40-63. This fluorophotometer is adaptable to a clinical setting and may prove useful in diagnosis and treatment of anomalies of tear production.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Aging*
  • Fluoresceins
  • Humans
  • Methods
  • Middle Aged
  • Spectrometry, Fluorescence / instrumentation
  • Tears / metabolism*
  • Time Factors


  • Fluoresceins