The Value of Water Drinking Test as a Clue for Short Term Intraocular Pressure Fluctuation

Abstract

G laucoma is a progressive optic neuropathy that leads to irreversible visual impairment if not properly treated (Chauhan and Drance, 1992). Elevated intraocular pressure is a major risk factor for the development of glaucoma (Mansouri and Weinreb, 2012). Many scientists believed that its reduction is beneficial in slowing down the glaucomatous changes of the optic nerves and visual field (Leske et al., 2003). However, glaucoma may progress even after intraocular pressure ‘control’ has been achieved (Asrani et al, 2000). One hypothesis suggests intraocular pressure spikes as a cause, these are not detected by usual one time office measurements. Studies demonstrated that almost one third of patients with single intraocular pressure measurements taken at office hours had pressure peaks only detected by a 24-hour intraocular pressure curve (Drance, 1963). The 24-hour measurement of intraocular pressure would be ideal to detect intraocular pressure peaks. However, time constraints and costs are major problems. Alternate methods are required to detect any intraocular pressure fluctuations and peaks, so the modified diurnal intraocular pressure measurement has become a common office practice because of its practicality (Zeimer, 1996). The water drinking test was first describ