Intraocular pressure change measured by Goldmann tonometry after laser in situ keratomileusis

Abstract

Intraocular pressure after LASIK decreased by a mean of 1.9 +/- 2.9 mm Hg. The cause of the decrease remains unknown.

Decrease in intraocular pressure following orthokeratology measured with a noncontact tonometer

“…IOP measurements have been found to be decreased after laser in situ keratomileusis (LASIK) [19][20][21]. LASIK surgery involves the cutting of collagen bundles in the corneal stroma, resulting in a decrease in both the CCT and corneal rigidity and a consequent underestimation of IOP [20,21].…”

Dynamic contour tonometry versus Goldmann applanation tonometry: a comparative study

“…In contrast, in eyes that have undergone LASIK, DCT has proven more reliable than GAT, which tends to measure artificially lower values [6,7,11,13,14,[20][21][22][23][24]31]. It can, however, be speculated that the iatrogenic thinning of the cornea, as happens in laser refractive ablation, may leave the cornea with different indentation properties than a cornea that is congenitally of the same thickness.…”

“…On statistical grounds, an upper cut-off value of 21 mmHg is used to differentiate between normal and elevated IOP. The widely accepted international gold standard for the measurement of IOP is Goldmann applanation tonometry (GAT); however, the accuracy of this method has been questioned in eyes with abnormal central corneal thickness (CCT) and structural corneal rigidity [3,10,19,26,28,29], and in eyes that have undergone laser in situ keratomileusis (LASIK) [6,7,11,13,14,[20][21][22][23][24]31]. Goldmann and Schmidt determined that surface tension and corneal rigidity would nullify one another and could therefore be ignored when using a tonometer head of 3.06 mm in diameter and a normal CCT of 500 μm [15].…”

Influence of corneal biomechanical properties on intraocular pressure measurement

“…[1][2][3][4][5][6][7][8][9][10] The accuracy of IOP measurement is crucial in the screening, diagnosis, and management of glaucoma. Refractive surgery improves visual performance by modifying the cornea's thickness, curvature, and structure, which are the factors known to affect the accuracy of routine IOP measurement by Goldmann applanation tonometry.…”