Applanation tonometer correlations

The Goldmann, Mackay-Marg, and Non-contact tonometers were compared on 25 subjects to establish correlations between measurements of intraocular pressure by these instruments. Topical anesthetic was used for the Goldmann and Mackay-Marg readings only. Correlations were high: between the Goldmann and the Non-contact, +0.93; between the Mackay-Marg and the Non-contact, +0.81; and between the Goldmann and the Mackay-Marg, +0.87.