Evaluation of daily changes of Intraocular pressure in glaucomatous patients with modified diurnal tension curve versus water drinking test

Abstract

Abstract Background Glaucoma is a chronic optic neuropathy characterized by the excavation of the optic disc due to atrophy of the retinal ganglion cells. A progression of such atrophy leads to reduction of the visual field and eventually to the loss of sight at the end-stage of the disease, Glaucoma is the second leading cause of blindness worldwide Objectives To study the correlation between intraocular pressure (IOP) fluctuation during water drinking test (WDT) and the IOP fluctuation of modified diurnal tension curve (mDTC) in glaucomatous eyes Patients and Methods Fifty participants (24 males and 26 females) were recruited in this prospective study; forty participants with known Primary Open Angle Glaucoma and the other ten participants with non- glaucomatous healthy eyes which served as control. Patients attending the outpatient clinic at Al-Demerdash Hospital and Cairo Fatemic Hospital from October 2018 to March 2019 were prospectively recruited. Four IOP measurements were taken at 8:00 am, 12:00 pm, 4:00 pm and 8:00 pm which represented the mDTC, while WDT was represented by a single measurement of IOP before ingestion of one liter of water over five minutes, followed by three IOP measurements after ingestion of this amount of water at thirty minute intervals. Results Distribution of the studied participants as regards Age and sex: 50 participants were included in the this study. 40 presented the case group (20 males and 20 females) and the mean age of the case group was 54.7 years, 10 presented the control group(4 males and 6 females) and the mean age of the control group was 51.2years. 59% of participants had a peak IOP at 8:00 am, while 10% had a peak IOP at 12:00 pm, 6% at 4:00 pm and 25% of the participants had IOP peak at 8:00 pm during the mDTC. In the WDT, 96% of the participants had a peak IOP after 30 minutes of ingesting one liter of water, while 4% had a peak IOP after 60 minutes. None of the participants had IOP peak after 90 minutes of ingesting one liter of water.. The IOP fluctuations detected during the WDT were significantly correlated to fluctuations observed during the mDTC. Conclusion The data of this study suggested that WDT can be used as a useful provocative test for the detection of the diurnal IOP peaks and fluctuation observed in the glaucoma patients.