Effect of temperature and humidity in the Schirmer tear test.

THE Schirmer I tear test developed and standardized by Halberg and Berens, New York City (Contactisol Inc. Lindenhurst, N.Y.) is a useful screening procedure for keratoconjunctivitis sicca in large numbers of patients suffering from various connective tissue disorders. When all the patients attending a centre for rheumatic diseases were subjected to this test it was noted that a surprisingly high percentage of in-patients had positive Schirmer I readings (less than 15 mm.). At the time of writing, 338 in-patients (age range 18 to 72 years, mean 56) including 250 females and 88 males, had been examined. In 65 patients (20 per cent.) whose ages ranged from 25 to 70 years (mean 50 5), 123 eyes had shown apparently reduced tear flow, 78 producing less than 5 mm. of wetting. When, however, the test was repeated within the week at an ophthalmic out-patients department, all the results were negative. The 65 patients were tested the following week in the rheumatic hospital and tear flow was again apparently reduced in 110 eyes.