[Importance of central corneal thickness when studying ocular hypertensive eyes, glaucoma suspects and preperimetric glaucomatous eyes].

PURPOSE To compare the central corneal thickness, measured with an ultrasound pachymeter, in normal subjects, those with ocular hypertension, glaucoma suspects and patients with preperimetric glaucoma. METHODS 61 normal eyes (control group), 131 eyes with ocular hypertension, 62 glaucoma suspects (optic nerve head morphology compatible with glaucoma) and 36 patients with preperimetric glaucoma (abnormal short-wavelength automated perimetry) were prospectively and consecutively selected. Scatter plots of central corneal thickness, against the intraocular pressure values were calculated for each of the study groups. Ultrasound pachymetry measurements were compared between those with normal eyes and the other groups. RESULTS Ocular hypertensive subjects had higher pachymetry values than the control group (p=0.009). No differences were found in the central corneal thickness between normal eyes and those who were glaucoma suspects, and between normal and preperimetric glaucomatous eyes. A mild direct logarithmic correlation was evident between central corneal thickness and the Goldmann tonometry result in the ocular hypertensive group. CONCLUSIONS Ocular hypertensive subjects had thicker corneas than the other groups studied. Glaucoma suspects and preperimetric glaucoma patients had similar corneal thickness to the control group.