Head Elevation and Intraocular Pressure in Glaucoma.

ABSTRACT

PURPOSE: To investigate the effect of different methods of head elevation on intraocular pressure (IOP) in patients with open-angle glaucoma (OAG). METHODS: Seventy-one patients of OAG were included in this prospective observational study. We measured IOP in the sitting position and in the supine positions with head flat and 30-degree up using two different methods: (1) bed head elevation (BHE) and (2) using multiple pillows (MP). We measured IOP using Tonopen AVIA in both eyes 10 minutes after assuming each position in a randomized sequence. By comparing the mean deviation (MD) of visual field between both eyes of a patient, we classified the eyes into either the better-MD eye or worse-MD eye. RESULTS: Compared with that measured in the supine position with head flat, the mean IOP was significantly lower when measured in the supine position with the head 30 degrees up by BHE, with an average drop of 2.0 mmHg (p < 0.001), whereas the mean IOP did not differ significantly when measured in the supine position with head 30 degrees up using MP (p = 0.081). Twenty-five (35.2%) patients showed IOP elevation when the head was kept up by MP. Compared between the better-MD and worse-MD eye, the IOPs did not differ in all positions. The mean IOP of the better-MD eye was lower in the 30-degree head-up (-1.9 mmHg, BHE; -0.8 mmHg, MP) positions compared with that in the flat-lying position, whereas the mean IOP of the worse-MD eye did not differ between the lying flat position and the head-up position with MP. CONCLUSIONS: Different head-elevating methods had different influences on IOPs of glaucoma patients in the supine position. Although raising the bed head by 30 degrees significantly lowers IOP compared to the supine position, resting on multiple pillows does not appear to offer the same IOP reduction in glaucoma patients.