Abstract

DIAZ ALEMAN, VT et al. Nomogram for ocular hypertension progression risk based on the Ocular Hypertension Treatment Study. Arch Soc Esp Oftalmol [online]. 2005, vol.80, n.3, pp.151-154. ISSN 0365-6691.

Introduction: A practical nomogram has been designed in order to present the results obtained from the Ocular Hypertension Study (Gordon et al. Arch Ophthalmol 2002; 120: 714-720), where the relation between intraocular pressure (IOP) and corneal thickness becomes apparent, involving the risk of evolution from ocular hypertension into glaucoma within a 6 year period. Material and Methods: We used a multiple logarithmic regression for the nine parameters shown in figure 1 of the above mentioned paper. Results: A correlation coefficient of 0.91 (p<0.001) permits to establish the following equation: Probability of evolution (%) = 13539.5 x (1.1385 ^IOP) x (0.9818 ^{CORNEAL THICKNESS}) This implies that a variation of 10 microns on corneal thickness leads to an IOP’s modification of 1.5 mmHg in the same sense. From these data, we designed the nomogram included in this paper. Conclusions: IOP and pachymetry together allow an estimation of the risk of evolution from ocular hypertension into glaucoma in a graphical practical way. From this indirect estimation, the influence of corneal thickness on IOP’s measure seems to be much higher than previously estimated.

Keywords : Glaucoma; intraocular pressure; corneal thickness; tonometry; pachymetry.