The Efficacy of Deep Sclerectomy on Posture-induced Intraocular Pressure Changes

PURPOSE: The purpose of this study was to evaluate the efficacy of nonpenetrating deep sclerectomy (NPDS) on posture-induced intraocular pressure (IOP) changes in open-angle glaucoma (OAG). MATERIALS AND METHODS: Twenty-five eyes of 25 patients with OAG that underwent NPDS were included in this study. IOP was measured with the IcarePro (ICP) tonometer in the sitting, supine, dependent lateral decubitus position (DLDP), and nondependent lateral decubitus position (NDLDP) before surgery, and at 1 and 3 months after surgery. RESULTS: The mean baseline IOP measured in the sitting position was 20.5±8.4 mm Hg with Goldmann applanation tonometry and 19.6±6.5 mm Hg with ICP. At 1 and 3 months after NPDS, mean IOP decreased significantly in each position (P<0.001). At each time point, mean IOP was higher in all lying positions than in the sitting position (P<0.001) and higher in the DLDP than in the supine and NDLDP positions (P<0.001 and P=0.001). Posture-induced IOP changes between the sitting and supine position, DLDP, and NDLDP, respectively, were significantly reduced by 77% (P=0.009), 60% (P=0.001), and 82% (P=0.01) at 1 month and by 79% (P=0.004), 70% (P<0.001), and 79% (P<0.001) at 3 months after surgery. The IOP fluctuation reduction was significantly inferior when considering sitting-DLDP than other postural changes. CONCLUSIONS: NPDS is effective in lowering the mean IOP in all body positions and also the postural IOP fluctuations. The mean IOP in the DLDP remained higher than in the other body positions. This posture should be avoided in patients with asymmetric OAG.