Abstract
Abstract: :
Purpose: to verify if there is a correlation between the central corneal thickness (CCT) and the intraocular pressure (IOP) measurements during the daily curve of intraocular pressure (DCPo), including the CCT and IOP measurements in bed at 6 a.m. and the ocular axial length. Methods: 114 eyes from 73 patients were prospectively studied. Forty–three patients (84 eyes) had chronic open–angle glaucoma (group I) and 30 patients (30 eyes) were suspected of glaucoma (group II). Both groups were subjected to DCPo with measurements performed at 9 a.m., 12 p.m., 6 p.m., 10:30 p.m. (patient seated) and in the next day at 6 a.m. in the bed and in the dark before the patient gets up. DCPo in group I was made for treatment control. Using an ultrasonic pachymeter DGH 510e, CCT measurements were performed at 9 a.m. (after tonometry), 6 p.m. (before tonometry), 10:30 p.m. (after tonometry) and the next day at 6 a.m. in bed before the patient getting up (after tonometry). Before the CCT measurement at 9 a.m., using the same ultrasonic device but with other probe, the ocular axial length of the patients of both groups was measured. Results: the mean ocular axial length was 23.07±0.95 mm (group I) and 23.62±1.27 mm (group II) with no statistically significant difference between them. In the total sample and, separately in each group, the mean IOP was more elevated in bed at 6 a.m., decreasing in the followings hours. The comparison between the two groups showed a statistically significant mean IOP lower in the group II (suspected glaucoma) than in the group I (chronic open–angle glaucoma) in all hours of measurements. CCT presented, in both groups, higher mean values at 6 a.m.: 535.2±35.5 µm (group I) and 538.2±38.7 µm (group II) and lower values at 6 p.m.: 527.7±34.8 µm (group I) and at 9 a.m.: 529.0±33.7 µm (group II), respectively. There were no significant CCT changes among the different scheduled times within each group neither between both groups. The values of the correlation between IOP and CCT were low but statistically significant in all hours. Conclusions: in glaucomatous and suspected patients, there were no significant CCT variations at different hours of the day, what means that only one CCT measurement is enough. There was no evidence of a statistically difference in the CCT among suspected and glaucomatous patients. There was also no statistically significant difference in the ocular axial length between both groups.
Keywords: cornea: clinical science • cornea: clinical science • cornea: clinical science