Water-Drinking and Tonography in the Diagnosis of Glaucoma

Abstract

Although characteristic field loss and cupping of the optic nerve head establish a diagnosis of glaucoma, therapeutic efforts in the chronic simple variety of this disease depend upon early detection. Methods available for its diagnosis include tonometry, provocative tests, and tonography. The use of tonometry in the diagnosis of glaucoma rests upon the fact that elevated intraocular pressure is one of the characteristics of this disease process. Unfortunately, an increase in intraocular pressure has not always been present in all untreated glaucomatous eyes at the time of the examination. Extensive efforts have been devoted to eliciting the pressure elevation. In chronic simple glaucoma the drinking of 1 liter of water has been reported to produce an elevation of intraocular pressure of 8 mm. Hg or more in 29% of eyes.¹ Thus, this provocative test has permitted the detection of glaucoma in some eyes not diagnosed by tonometry alone, but,