advertisement
Abstract #20854 Published in IGR 10-1
Effects of Central Corneal Thickness on the Efficacy of Topical Ocular Hypotensive Medications
Johnson TV; Toris CB; Fan S; Camras CBJournal of Glaucoma 2008; 17: 89-99
See also comment(s) by James Brandt •
PURPOSE: To determine the effect of central corneal thickness (CCT) on the efficacy of intraocular pressure (IOP)-reducing drugs in patients with ocular hypertension (OHT). METHODS: This retrospective study analyzed research records of 115 OHT patients and 97 ocular normotensive (ONT) volunteers. CCT was measured by slit-lamp pachymetry and IOP by pneumatonometry. The OHT patients were divided into Thick (>540 μm, n=52) and Thin (≤540 μm, n=63) Cornea groups. Measurements in the OHT group were made after washout of all IOP-lowering drugs and at 1 week of treatment with latanoprost 0.005%, dorzolamide 2%, brimonidine 0.2%, apraclonidine 0.5%, pilocarpine 2%, or unoprostone 0.15% to 1 eye and vehicle contralaterally. ONT volunteers also were divided into Thick (n=34) and Thin (n=63) Cornea groups. Results were compared between groups using unpaired t tests or nonparametric Wilcoxon tests and within groups using linear regression analyses. RESULTS: Baseline IOPs were not different between CCT groups of OHT patients or of ONT volunteers. After 1 week of drug treatment, IOP was significantly (P=0.02) lower in the OHT Thin Cornea group (16.0±3.0 mmHg, mean±SD) than the OHT Thick Cornea group (17.4±2.8 mmHg). There was a positive correlation between IOP and CCT (R2=0.06, P=0.007) in OHT drug-treated eyes, but not OHT vehicle-treated or ONT untreated eyes. The final IOP was significantly lower in the Thin than the Thick Cornea group treated with brimonidine (P=0.02) but not with latanoprost (P=0.91). CONCLUSIONS: When dosed with IOP lowering drugs, eyes with thinner corneas had lower IOPs than eyes with thicker corneas. This suggests a reduced efficacy of some glaucoma medications in ocular hypertensive patients with thick corneas.
Classification:
2.2 Cornea (Part of: 2 Anatomical structures in glaucoma)
11.1 General management, indication (Part of: 11 Medical treatment)
9.2.1 Ocular hypertension (Part of: 9 Clinical forms of glaucomas > 9.2 Primary open angle glaucomas)
