Matías Pérez Miranda¹*, Mauricio Pérez González^1,2, Camila Martínez Sanguesa¹, Patricia Muena Vega¹, Piero Barrera Arshavin¹ and Gigliola Basso Barra¹

¹Servicio de Otalmología, Hospital Clínico San Borja Arriarán, Santiago, Chile
²Universidad de Chile, Santiago, Chile

*Corresponding Author: Matías Pérez Miranda, Servicio de Otalmología, Hospital Clínico San Borja Arriarán, Santiago, Chile.

Received: July 16, 2025; Published: August 20, 2025

Abstract

Introduction: Intraocular pressure (IOP) measurement with Goldmann applanation tonometry (GAT) is currently considered the gold standard. AccuPen tonometry is a portable and rapid method, but there is no local evidence supporting its reliability.

Objective: To determine whether IOP measurements obtained with AccuPen are comparable to those obtained with Goldmann tonometry.

Materials and Methods: A prospective comparative study including 114 patients (228 eyes) measured with both AccuPen and Goldmann tonometry. Data collected included age, sex, glaucoma diagnosis (yes/no), and central corneal thickness (CCT). Descriptive and inferential statistics were applied, with a significance level of 5% to compare differences.

Results: 69.3% of participants were female, with a mean age of 63.4 years (SD = 13.9), ranging from 17 to 87 years. Goldmann tonometry: 17.6 ± 7.0 mmHg (SD = 6.95) (range: 6–60 mmHg). AccuPen tonometry: 18.6 ± 7.2 mmHg (SD = 7.15) (range: 5–57 mmHg). The mean difference between methods was -0.99 mmHg (SD = 3.16) (range: -12 to 11 mmHg), which was statistically significant (p < 0.001), with a medium effect size (D = -0.3125). 56.1% of cases: Goldmann > AccuPen, 30.3% of cases: AccuPen > Goldmann, 13.6% of cases: Identical measurements. Glaucoma diagnosis was present in 53.5% of cases. The mean central corneal thickness was 545.1 µm (SD = 40.7) (range: 333–737 µm). Bland-Altman analysis showed that all differences were within the [-6, +6] mmHg range, with 89.9% within [-5, +5], 84.6% within [-4, +4], and 77.1% within [-3, +3]. Sex, glaucoma diagnosis, and CCT were analyzed as differentiation factors, with no statistically significant differences observed.

Conclusions: There is a significant difference between both methods, with only a small fraction of identical measurements, making them non-interchangeable. However, the majority of differences fell within ± 3 mmHg, suggesting that AccuPen could be a reasonable alternative for screening and in cases where Goldmann tonometry is not feasible.

 Keywords: AccuPen; Goldmann; Tonometry; Glaucoma

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Citation

Citation: Matías Pérez Miranda., et al. “Comparison of Intraocular Pressure Measured with AccuPen and Goldmann in a Glaucoma Consultation”.Acta Scientific Medical Sciences 9.9 (2025): 46-52.

Copyright

Copyright: © 2025 Matías Pérez Miranda., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.