Abstract
Purpose: :
To assess whether there is a correlation between the intraocular pressure (IOP) rise after the supine test (ST) or the water drinking test (WDT) and recent progression of open angle glaucoma (OAG).
Methods: :
112 eyes from 61 patients with OAG; Primary Open Angle Glaucoma (POAG), Normal Tension Glaucoma (NTG), Pseudoexfoliative Glaucoma (PXG), and Pigment Dispersion Glaucoma (PDG) participated in both supine and water drinking tests. Baseline IOP was measured by Goldmann Applanation Tonometry (GAT), Pneumotonometry (PT) and Dynamic Contour Tonometry (DCT). For the supine test, IOP was measured by PT at 1 and 5 minutes in the supine position. A second baseline IOP was recorded 5 minutes after returning to an upright position. For the water drinking test, patients were asked to consume 800 ml of water within ten minutes and IOP was measured at 15 and 30 minutes. Baseline DCT and Ocular Pulse Amplitude (OPA) measurements were also recorded and repeated 30 minutes after water consumption. Patients were retrospectively classified by masked observer into "glaucoma progressive" (27 eyes, 24.1%) and "non-progressive" (85 eyes, 75.9%) groups based on changes or stability in their standard white-on-white perimetry and scanning laser ophthalmoscopy. Mean IOP changes in each test and correlation with the progression were analysed.
Results: :
There was a significant increase in the mean IOP after the ST and WDT for all three measurement methods (p < 0.01). Thirty minutes after the WDT, the glaucoma progressive group showed a significantly higher IOP rise by GAT and PT than the non-progressive group (4.1 ± 4.1mmHg and 5.1 ± 2.8 versus 2.4 ± 2.2 and 3.2 ± 2.7; mean values ± SD) (p = 0.01 and 0.02). No significant difference could be detected in the change of the DCT-IOP and OPA.
Conclusions: :
The IOP increased significantly in both supine and water drinking test. However, the degree of elevation of IOP after the WDT 30 minutes shows a correlation with recent progression of OAG. The ST was not correlated with progression in our series.
Keywords: intraocular pressure • visual fields • optic disc