Tear osmolarity and ocular surface disease in keratoconjunctivitis sicca
J. P. Gilbard and R. L. Farris
Tear osmolarity and Rose Bengal staining were studied in a group of
patients with keratoconjunctivitis sicca (KCS) before and after treatment
with isotonic and one-half isotonic saline to compare treatment with these
two solutions and to ascertain whether tear film osmolarity could be
correlated with ocular surface disease. When 20 KCS eyes were treated with
isotonic saline drops every three hours for one week, the average (+/-SD)
tear osmolarity decreased from 365 +/- 77 mOsm/L to 329 +/- 47 mOsm/L, and
the average (+/-SD) Rose Bengal staining score decreased from 4.1 +/- 3.1
to 3.6 +/- 3.3. There was no objective difference between treatment with
isotonic and one-half isotonic solutions, in a double-masked comparison,
however, four of five patients with diagnostically significant Rose Bengal
staining preferred the half isotonic solution. There was a significant
positive correlation between tear film osmolarity and Rose Bengal staining.