Abstract
Purpose: :
The water-drinking test (WDT) has been proposed as a stress test to evaluate intraocular pressure (IOP) elevation in glaucomatous patients and suspects. The purpose of this study was to determine the time of peak detection during the WDT in patients with primary open angle glaucoma (POAG) with and without treatment.
Methods: :
One hundred and eighty seven eyes of 187 patients underwent the WDT before and after initial treatment. 101 eyes were using the fixed combination brimonidine/timolol (BT) and 86 eyes were under dorzolamide/timolol (DT) combination. After baseline IOP measurement, all patients underwent WDT by drinking 1000 mL of bottled water in 5 minutes. IOP measurements were taken at 15, 30 and 45 minutes after ingestion of the water. The main outcomes measured were the IOP peak and time to reach the IOP peak.
Results: :
The mean baseline IOP for the WDT before initial treatment was 22.6 ± 3.4 mmHg (range 12 to 30 mmHg), and the average IOP peak was 27.3 ± 4.4 mmHg (range 17 to 40 mmHg). After 3 months of treatment the mean baseline IOP for the WDT was 16.3 ± 2.7mmHg (range 10 to 23 mmHg), whereas the mean IOP peak was 20.8 ± 3.6 mmHg (range 13 to 33 mmHg) in BT group and 16.2 ± 2.9 mmHg (range 7 to 26 mmHg), and the mean IOP peak was 20.7 ± 3.6 mmHg (range 14 to 32 mmHg) in DT group. The percentage of peak at the different time of measurement was 26.7%, 27.7% and 31.4% at 15 minutes, 52.4%, 56.4% and 54.7% at 30 minutes and 18.7%, 15.8% and 14.0 % at 45 minutes with no treatment, using BT and DT respectively. Considering the eyes that the peak occurred at 15 minutes and remained until 30 minutes, the percentage at 30 minutes raised to 63.1% (no treatment), 67.3% (BT) and 60.5% (DT).
Conclusions: :
In average, the measurement at 30 minutes during the WTD showed the peak in 63.1% of the eyes without medication, 67.3% and 60.5% under treatment with BT and DT respectively. These results suggest the importance and significance of the 30 minutes measurement during the WDT.
Keywords: intraocular pressure • outflow: trabecular meshwork