Comparison of Intraocular Pressure Measurement by Goldmann Applanation Tonometer and Air Puff Tonometer in Silicone Filled Eyes.

Background: To compare intraocular pressure (IOP) measurements in silicone filled eyes by Goldmann applanation tonometer (GAT) and air puff tonometer (APT). Aim: The purpose of this study was to evaluate the role of APT by comparing the measurements of IOP made using it with those made using a GAT. Methods: In this prospective comparative study, 40 eyes with silicone oil tamponade were included. IOP was measured by GAT and air puff tonometer at least 1 month from vitrectomy. Results: in eyes with silicone oil, IOP was 21.35±12.34 mmHg and 19.46±5.29 mmHg using GAT and APT, respectively (p>0.05) and this difference was not statistically significant (p=0.074). In addition, no significant correlation was detected between IOP measurements using both techniques and gender, and lens status. Conclusion: It seems that GAT provided higher IOP measurements by 3.34 mmHg (95% CI = 2.15 to 4.53 mmHg) on average compared with APT but the difference between the two IOP measurements was statistically non-significant (p >0.05), in silicone filled eyes. The further assessment of available methods for IOP measurement could possibly establish the most accurate technique for IOP estimation in silicone filled eyes.