Intraocular Pressure Measurement Accuracy and Repeatability of a Modified Goldmann Prism: Multicenter Randomized Clinical Trial

• Published in: American journal of ophthalmology Vol. 196; pp. 145 - 153
• Main Authors: McCafferty, Sean, Tetrault, Kyle, McColgin, Ann, Chue, Warren, Levine, Jason, Muller, Melissa
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.12.2018
• Subjects: Adult; Analysis of Variance; Female; Humans; Intraocular Pressure - physiology; Male; Middle Aged; Ocular Hypertension - diagnosis; Prospective Studies; Reproducibility of Results; Tonometry, Ocular - instrumentation; Tonometry, Ocular - standards
• ISSN: 0002-9394; 1879-1891; 1879-1891
• DOI: 10.1016/j.ajo.2018.08.051

To clinically evaluate a modified surface Goldmann applanation tomometer (GAT) prism for intraocular pressure (IOP) accuracy, repeatability, and safety. Prospective, open-label, randomized, controlled, multicenter reference device reliability and validity analysis. A GAT and a modified surface GAT prism measured IOP on 173 unique eyes. The study design and analysis complied with FDA 510(k) and ANSIZ80.10-2014 guidelines. All eyes were randomized to IOP measurement by 1 of 5 standard prisms or 5 modified prisms, each from a different manufacturing lot. Pressures were measured by 6 investigators, 2 times with each prism, for a total of 1384 IOP measurements. Analysis included Bland-Altman difference accuracy, intraoperator and interoperator IOP measurement, and manufactured lot repeatability. Bland-Altman indicated no IOP measurements pairs outside the ±5 mm Hg guidelines. Operator and manufactured lot repeatability F tests and 1-way ANOVAs indicated no statistical difference between the standard and modified prisms (all P > .10). The difference in IOP measurements of the standard and modified prisms correlated well to Dresdner central corneal thickness (CCT) correction (P = .01). A modified surface replacement prism is statistically equivalent to a flat-surfaced prism. The modified surface prism indicated statistically significant correction for CCT requiring further testing outside the ANSI standard limits (0.500 mm < CCT < 0.600 mm) to examine its full potential.