Normative Data of Ocular Pulse Amplitude Value and Intraocular Pressure measured by Dynamic Contour Tonometry in a Thai Population.

1. Chutima Supawavej, MD¹
2. Patsaran Thanasupan, MD²
3. Archara Supavavej, MD³
4. Boonsong Wanichwecharungruang, MD⁴

¹BNH Hospital, Bangkok, Thailand
²Banphaeo Hospital, Samutsakhon, Thailand
³Department of Medicine, Faculty of Medicine Chulalongkorn University, Bangkok, Thailand
⁴Rajavithi Hospital, Rangsit University, Bangkok, Thailand

Purpose: To evaluate the ocular pulse amplitude (OPA) value and intraocular pressure (IOP) measured by dynamic contour tonometry (DCT).

Method: Ninety eyes from 90 subjects were studied. The age varied from 21 to 73 years (mean 50.21) and with 67 female subjects (74.44%). Participants underwent a comprehensive ophthalmic examination including: visual acuity, spherical equivalent, corneal curvature, axial length and central corneal thickness (CCT). All participants underwent IOP measurements by Goldmann applanation tonometry (GAT). Three consecutive IOP and OPA values were assessed by DCT. Blood pressure and heart rate were obtained.

Results: The average OPA reading is 2.83 mmHg (range 0.7-5.9). Mean IOP as measured by DCT is 17.21 mmHg (range 13.4-25.7) when compared with mean IOP by GAT at 13.38 mmHg (range 10-25). DCT IOP values are statistically significantly different from mean IOP measured by GAT. The difference of IOP values between two instruments is 3.84 mmHg (95% confidence interval, 3.29 to 4.28). Mean CCT is 540.93 μm (range 458.3-631.67).

Conclusions: Dynamic contour tonometry gave statistically significantly higher IOP values than Goldmann applanation tonometry. Clinical implication of DCT should be considered particularly in glaucoma suspect subjects.

Financial disclosure(s): The authors have no proprietary or commercial interest in any materials discussed in this article.