Evaluation of the Water-Drinking Test

DIFFERENT degrees of reliability of the water-drinking test for glaucoma have been reported in the literature.This may partly be explained by the fact that an insufficient number of tests have been carried out on healthy subjects, so that the physiological limits of the response to the test were not clear.Furthermore, the incidence of positive results in glaucomatous eyes with a normal initial tension has generally not been kept apart from those found in eyes with initially high tension.Both criticisms apply to an earlier paper in this Journal (Leydhecker, 1950), and the present re-consideration of the subject has been stimulated by the work of Agarwal and Sharma (1953), in which similar errors seem to be contained.Previous Investigations (A) Effect of the Test on Normal Eyes.-Decker (1929) examined fifteen subjects and found no rise of tension above the limits of error of tonometry.Poos (1930) saw " in many cases " rises of 5 or 8 mm.Hg Schiotz.Wegner (1930) mentioned rises of " several" mm.Hg.Heegaard and Larsen (1931) obtained maximal rises of 4 mm.Hg.Ohm (1936) gave the increase of tension as a percentage of the initial tension so that his results are difficult to compare.Meves (1940) injected pituitary hormone (hypophysin), in addition to the ingestion of 1,000 ml.water, and observed a maximal rise of tension of 8 mm.Hg Schi6tz in six healthy eyes.Sugar (1948) who was the first to do a large number of tests on healthy subjects, found in 143 eyes a maximal rise of 9 mm.Hg or a ceiling of 32 mm.Hg.Honigmund (1951) examined seventy eyes of non-glaucomatous subjects after the inges- tion of 1,000 ml.water; in vegetative dystonia she observed rises of 10 or even 12 mm.Hg Schiotz in four eyes.Rohrschneider (1952) examined forty healthy students: in 30 per cent rises of 6 to 12 mm.Hg occurred; in six cases the ceiling was 30 or 32 mm.Hg, in three the rise was 10 mm.Hg, and in one 12 mm.Hg.Agarwal and Sharma (1953) obtained rises of 2 to 6 mm.Hg inr fifty healthy eyes, but in one considered to be pre-glaucomatous a rise of 10 mm.Hg occurred.(B) Incidence of Pathological Results in Glaucomatous Eyes.-The results of Schmidt (1929, 1931), Wegner (1930), Ohm (1936), and Sugar (1948) are difficult to evaluate, since the increase of tension in their cases is not fully stated.Majorova and Glinika (1939) did 44 tests on 23 patients and obtained a rise of 6 mm.Hg Schiotz or more in four out of twelve eyes.Bloomfield and Kellermann (1947) observed rises of 10 mm.Hg or more in twelve out of 22 eyes with simple glaucoma.Schmidt (1950) reported a ceiling of 30 mm.Hg or more in 60' 8 per cent of 250 glaucomatous eyes; amongst 33 tension curves of glaucomatous eyes with an initial tension below 30 mm.Hg there were eight with rises of 10 mm.Hg or more.Sugar (1948Sugar ( , 1951) ) observed rises of over 9 mm, Hg in 44 per cent. of 112 unoperated eyes with simple glaucoma; he points out (1951) that " with increasing levels of initial tension *