Korean J Ophthalmol.  2010 Jun;24(3):139-142. 10.3341/kjo.2010.24.3.139.

Evaluation of Corneal Biomechanical Properties Following Penetrating Keratoplasty Using the Ocular Response Analyzer

• Shin JY
• Choi JS
• Oh JY
• Kim MK
• Lee JH
• Wee WR

• KMID: 945982
• DOI: http://doi.org/10.3341/kjo.2010.24.3.139

Abstract

PURPOSE
To evaluate corneal biomechanical properties in eyes that had previously undergone penetrating keratoplasty (PK) using the ocular response analyzer (ORA). METHODS: We recruited 26 patients who had received unilateral PK. Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and cornea-compensated intraocular pressure (IOPcc) were measured with the ORA and were compared to the measurements from the contralateral eyes that did not undergo PK. RESULTS: The CH was 8.95+/-2.59 mmHg in eyes that underwent PK and 9.78+/-1.45 mmHg in the contralateral eyes that did not undergo PK (p=0.077). The CRF was 10.26+/-2.64 mmHg in post-PK eyes and 9.75+/-1.45 mmHg in the contralateral eyes (p=0.509), and the CH-CRF was significantly smaller in post-PK eyes (-1.31+/-2.32 mmHg in post-PK eyes vs. 0.03+/-0.88 mmHg in fellow eyes, p=0.016). The IOPg and IOPcc were significantly higher in the PK group than they were in the control group. The IOPcc's were 20.81+/-7.81 mmHg and 16.27+/-2.49 mmHg in post-PK and control eyes, respectively (p=0.011); and the IOPg's were 19.22+/-7.34 mmHg and 15.07+/-3.03 mmHg in post-PK and control eyes, respectively (p=0.019). The IOPcc-g's were 1.59+/-2.81 mmHg and 1.21+/-1.30 mmHg in post-PK and control eyes, respectively (p=0.412), and the central corneal thickness (CCT)'s were 489.11+/-90.60 microm and 556.24+/-42.84 microm in post-PK and control eyes, respectively (p=0.068). CONCLUSIONS: Following PK, CH tended to decrease while CRF tended to increase, significantly decreasing CH-CRF. A significantly higher intraocular pressure and a thinner CCT following PK may have contributed to the observed changes in these corneal biomechanical parameters.

Keyword

Cornea; Intraocular pressure; Penetrating keratoplasty

MeSH Terms

Adolescent
Adult
Aged
Cornea/*physiopathology
*Diagnostic Techniques, Ophthalmological
Elasticity
Female
Humans
Intraocular Pressure
*Keratoplasty, Penetrating
Male
Middle Aged
Postoperative Period
Young Adult

Figure

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  Fig. 1 Correlations of corneal hysteresis (CH) and corneal resistance factor (CRF) with cornea-compensated intraocular pressure (IOPcc) and Goldmann-correlated intraocular pressure (IOPg).

• 

  Fig. 2 Correlations of cornea-compensated intraocular pressure and Goldmann-correlated intraocular pressure (IOPcc-g) with corneal hysteresis (CH) and corneal resistance factor (CRF).

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