Accuracy of portable and traditional non-contact tonometers in measuring different intraocular pressure levels
10.3980/j.issn.1672-5123.2026.8.22
- VernacularTitle:便携式与传统非接触式眼压计测量不同眼压水平的准确性
- Author:
Xianyao PENG
1
;
Jiahui WANG
1
;
Jingwei HU
1
;
Jiaqi CHEN
1
;
Wuliang LI
1
;
Tianyu WANG
1
;
Yinan WU
1
;
Xiaoping XU
1
Author Information
1. Ningbo Eye Hospital, Ningbo 315040, Zhejiang Province, China
- Publication Type:Journal Article
- Keywords:
intraocular pressure;
Goldmann applanation tonometry;
portable non-contact tonometer;
central corneal thickness
- From:
International Eye Science
2026;26(8):1435-1441
- CountryChina
- Language:Chinese
-
Abstract:
AIM:To evaluate the accuracy of a portable non-contact tonometer(PNCT)compared with a traditional non-contact tonometer(NCT)in measuring intraocular pressure(IOP)at different levels.METHODS:Patients who presented to Ningbo Eye Hospital between January 2025 and January 2026 were retrospectively included. All patients underwent measurements using PNCT, NCT, and Goldmann applanation tonometry(GAT). Based on the GAT measurements, the patients were categorized into a low IOP group(IOP≤16 mmHg), a moderate IOP group(16 mmHg0.05). Spearman correlation analysis revealed that the IOP values measured by both PNCT and NCT were positively correlated with those measured by GAT(rs=0.86 and 0.84, respectively, P<0.05). Intraclass correlation coefficient(ICC)analysis demonstrated an ICC of 0.89 between PNCT and GAT(P<0.05), and 0.88 between NCT and GAT(P<0.05), with an overall ICC of 0.88 among the three instruments(P<0.05). Bland-Altman analysis indicated a mean bias of 0.1 mmHg [95% limits of agreement(LoA): -7.3 to 7.6 mmHg] between PNCT and GAT, and a mean bias of 0.1 mmHg(95%LoA: -8.4 to 8.6 mmHg)between NCT and GAT. Based on the GAT measurements, the eyes were categorized into a low IOP group(60 eyes, 32.6%, IOP≤16 mmHg), a moderate IOP group(63 eyes, 34.2%, 16 mmHg0.05), whereas the difference between NCT and GAT showed a positive correlation with CCT(rs=0.23, P<0.05).CONCLUSION:The IOP measurements obtained by PNCT, NCT, and GAT demonstrated strong correlation and good agreement, with PNCT being less influenced by CCT. However, as IOP levels increased, the measurement errors of both PNCT and NCT also increased. Therefore, PNCT and NCT readings should only serve as references and cannot replace GAT.
