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Abstract #53271 Published in IGR 15-2
Influence of corneal biomechanical properties on intraocular pressure differences between an air-puff tonometer and the Goldmann applanation tonometer
Tranchina L; Lombardo M; Oddone F; Serrao S; Lomoriello DS; Ducoli PJournal of Glaucoma 2013; 22: 416-421
PURPOSE: To estimate the influence of corneal properties on intraocular pressure (IOP) differences between an air-puff tonometer (NT530P; Nidek) and the Goldmann applanation tonometer (Haag-Streit). PATIENTS AND METHODS: The influence of central corneal thickness (CCT), keratometry, and Ocular Response Analyzer (Reichert) measurements of corneal viscoelasticity [corneal hysteresis (CH) and corneal resistance factor (CRF)] on IOP differences between tonometers was evaluated. RESULTS: The CRF was calculated to be the best predictor of the differences in IOP readings between tonometers (r2=0.23; P<0.001), followed by CCT (r2=0.15; P=0.003) and CH (r2=0.14; P=0.003). Keratometry performed very poorly as lone predictor of IOP differences. In a multiple regression model, CRF, CH, and CCT together accounted for 25% (r2=0.25; P<0.01) of the variance in IOP reading differences between tonometers. CONCLUSIONS: Corneal resistance to applanation induced by either contact or noncontact tonometers was calculated to be the most determinant factor in influencing IOP differences between applanation tonometers.
Dipartimento di Biopatologia e Diagnostica per Immagini, Sezione Oculistica, Università degli Studi Tor Vergata, Rome, Italy.
Full articleClassification:
6.1.1 Devices, techniques (Part of: 6 Clinical examination methods > 6.1 Intraocular pressure measurement; factors affecting IOP)
6.1.3 Factors affecting IOP (Part of: 6 Clinical examination methods > 6.1 Intraocular pressure measurement; factors affecting IOP)
