SE-U-0207-A Effect of Corneal Thickness on Measured IOP Several studies, including most notably the Ocular Hypertension Treatment Study (OHTS), have determined a significant relationship between central corneal thickness (CCT) and intraocular pressure (IOP), and the need to adjust IOP applanation tonomtery readings by a factor to consider the effect of CCT in order to understand the "true" IOP. The Sonomed Pacscan series of pachymeters allows for the user to enter the measured IOP and then automatically apply the adjustment algorithm to display the "true" IOP. For reference, the IOP correction values for various corneal thickness measures are shown in the table below: Corneal Thickness [um] 445 455 465 475 485 495 505 515 525 535 545 555 565 575 585 595 605 615 625 635 645 Correction Value [mmHg] +7 +6 +6 +5 +4 +4 +3 +2 +1 +1 0 -1 -1 -2 -3 -4 -4 -5 -6 -6 -7 For Reference Only Sonomed Escalon A Subsidiary of Escalon Medical Corp 1979 Marcus Avenue Lake Success, NY 11042 800-227-1285/516-354-0900 www.sonomedescalon.com