Abstract
Purpose: :
To compare dynamic contour tonometry (DCT) with Goldmann applanation Tonometry (GAT) in everyday glaucoma practice.
Methods: :
The present study included 132 eyes of 66 patients (23 with open–angle glaucoma, 5 with angle closure , and 38 with ocular hypertension). Pachymetry by a non contact slitlamp–mounted pachymeter using optical low coherence reflectometry technology (OLCR– Haag Sreit) GAT, and DCT in that order were performed in all patients.Intraocular pressures as measured by DCT, and GAT were compared with each other . Intraocular pressures as measured by DCT were compared with GAT measurements adjusted according to the measured central corneal thickness (CCT) by OLCR software (Tonofit program).
Results: :
Mean DCT measurements (20.5+/–4.9 mm Hg) were significantly (P =0,05) higher than GAT values (19.1 +/– 6 mm Hg),correlating significantly with each other (r = .90, P < .001).This correlation was not different for GAT adjusted for CCT (r= 0.91 P < .001). The mean difference between DCT and GAT was 1.42 (7.3 to – 6.8) mm Hg. Neither GAT nor DCT showed a significant correlation with CCT (536+/–32, range 458–626 micron).
Conclusions: :
In glaucomatous patients, DCT allows suitable and reliable IOP measurements which are in good concordance with GAT. Variation of CCT cannot by itself explain the different measurements of DCT and GAT observed in a number of eyes.
Keywords: intraocular pressure • clinical (human) or epidemiologic studies: systems/equipment/techniques • clinical laboratory testing