Relation between optical coherence tomography and optical pachymetry meaurement of corneal welling induced by hypoxia

PURPOE: To determine the relation between optical coherence tomography (OCT) and optical pachymetry (OP) meaurement of corneal welling induced by hypoxia. DEIGN: Experimental tudy. METHOD: One randomly elected eye of 20 noncontact len wearer (10 male and 10 female, age 35.6 ± 9.6 year) wa patched during 3 hour of oft contact len (CL) wear while the contralateral eye acted a control. Central corneal thickne of both eye wa meaured before and after CL wear uing OCT and OP in randomized order. REULT: Baeline central corneal thickne wa 523.6 ± 33.0 μm (mean ± tandard deviation [D]) meaured with OCT and 490.6 ± 25.5 μm with OP. Immediately after contact len removal, corneal thickne meaured with OCT increaed by 13.8 ± 2.3% compared with 12.1 ± 1.8% (paired t tet: P < .001) meaured with OP. Thereafter, corneal thickne decreaed at the rate of 5.6% per hour for OCT and 5.4% per hour for OP. The difference in thickne between intrument before len inertion, which wa 33 μm compared with the difference after len removal (edematou cornea), which ranged from 46 to 41 μm. The difference between intrument decreaed during the corneal dewelling period after len removal. The correlation coefficient between OCT and OP wa 0.914 before len inertion and 0.932 after len removal. CONCLUION: Thi tudy ha demontrated the difference of corneal thickne meaured with OCT and OP. Although both intrument are correlated highly in all condition teted, OCT may overetimate corneal thickne in normal and edematou cornea.