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Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
A New Provocative Test for Glaucoma
Fabio N Kanadani1, Tca Moreira2, L F Campos3
1Chief, Department of Ophthalmology, Medical Science Ophthalmology Institute, Belo Horizonte, Brazil.
Purpose:
To compare the effects of the water-drinking test (WDT) with the 30° inverted body position test on intraocular pressure (IOP) in normal patients, suspected glaucoma patients and glaucoma patients.
Materials And Methods:
Based on clinical evaluation of the optic disk, IOP, and standard achromatic perimetry (SAP) of 71 eyes, 18 were "normal" (normal SAP and optic disk evaluation, and IOP < 21 mm Hg), 30 were "glaucoma suspect" (GS; normal SAP, cup/disk (C/D) ratio > 0.5 or asymmetry > 0.2 and/or ocular hypertension), and 31 had "early glaucoma" (MD < -6 dB, glaucomatous optic neuropathy). Standard achromatic perimetry was performed with the Octopus 3.1.1 Dynamic 24-2 program. Patients fasted before the WDT, and four measurements were performed at basal, 15', 30, and 45' after drinking 1 liter of water (WDT) in 5 minutes. In the 30° inverted position, IOP measurement with Perkins applanation tonometer was taken after 5 minutes lying down.
Results:
There was a statistical difference in all groups between the basal IOP and peak IOP during the WDT (p < 0.001) and in the inverted position IOP (p < 0.001). Controls (p = 0.50), suspects (p = 0.41) and glaucoma patients (p = 1.0) did not exhibit a difference between WDT-IOP and inverted position IOP.
Conclusion:
The 30° inverted position test was as efficient as WDT in detecting peak IOP. This new provocative test is easier, faster and more comfortable for both patients and doctors. How to cite this article: Kanadani FN, Moreira TCA, Campos LF, Vianello MP, Corradi J, Dorairaj SK, Freitas ALA, Ritch R. A New Provocative Test for Glaucoma. J Curr Glaucoma Pract 2016;10(1): 1-3.
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