Evaluation Of Corneal Hysteresis And Intraocular Pressure Measurement Following Uneventful Phacoemulsification Cataract Surgery

To evaluate the trend of corneal hysteresis (CH), central corneal thickness (CCT) and corneal edema and to note the level of agreement in intraocular pressure measurement (IOP) between different instruments, following uneventful phacoemulsification.

Tertiary care setting in South India

In this prospective cohort study, 59 eyes of 59 patients underwent measurement with Ocular response analyser (ORA) and IOP assessment with Goldman Applanation Tonometry (GAT), Non-Contact Tonometry (NCT) and rebound tonometry before and after uneventful phacoemulsification. The trend analysis was performed, and the level of agreement was assessed by intra-class correlation coefficient (ICC) and Bland-Altman plots.

The mean age was 61.14 ±8.46 years, with 28 (47.5%) of them being females. CH significantly decreased postoperatively (p value <0.001) at all time points (baseline: 9.05± 1.40 mmHg; POD 1:7.26± 1.51 mmHg) but returned to baseline by POD 6 weeks. CCT normalized by POD 2 weeks (baseline: 526µm; POD 1: 570µm, POD 1 week: 540µm, and POD 2 weeks: 524µm). CH declined with increasing severity of corneal edema. GAT exhibited the highest consistency with IOPcc (ICC >0.90 at all time points, ranging from 0.90 to 0.94, and bias 2.03 to 1.72).  GAT and iCare showed strong agreement (ICC 0.89–0.97, bias -0.32 to -1.05), while IOPcc and iCare demonstrated moderate consistency (ICC 0.82–0.94, bias -0.32 to 0.09).

Both CH and CCT showed changes following cataract surgery, but gradually reverted to baseline over time. There is a strong agreement between GAT and IOPcc, and GAT and iCare, allowing interchangeable use in corneal edema.