Correlation of Perkins Hand-Held Applanation Tonometer with Non-Contact Tonometer

Abstract

Aim: To correlate the IOP by the use of Perkins hand-held applanation tonometer (PAT) with Non-contact

tonometer (NCT). Materials & Methods: Prospective cross-sectional study done on 148 eyes & 3 readings

were taken for each method & mean calculated. Statistical analysis: Unpaired-T test & Correlation-co

efficient, Sensitivity & Specificity were calculated for the NCT. Results: Mean age of subjects was 56.01±

9.73 yrs. Mean IOP with PAT & NCT 15.43 mmHg (95% CI 15.14–15.76) & 15.13 mmHg (95% CI 14.81–

15.46) respectively. NCT shows excellent agreement with PAT. Correlation coefficient(r) of IOP measured

by NCT & PAT is 0.97 & 0.91 for RE & LE respectively with p value <0.05, showed strong positive

correlation between the IOP measured by NCT & PAT. The NCT showed high sensitivity 86% & high

specificity 97.9 % respectively, coming across an excellent agreement with PAT. Interpretation: NCT is

easy to operate (non medical & Paramedical staff), minimum risk of infection & without any observer bias.

Only drawback is the cost. Conclusion: The current study shows that the NCT compares well with the PAT.

The NCT can be used as a reliable screening tool.