Corneal thickness increases after cataract surgery, may affect IOP measurements

Central corneal thickness increases immediately after phacoemulsification and gradually returns to normal over 1 week postop, according to a study by researchers in the United Kingdom. The increased corneal thickness may affect IOP measurements; thus, not all eyes with a rise in IOP may need to be treated, the authors noted.

Sachin M. Salvi, MRCOphth, and colleagues evaluated the changes in central corneal thickness (CCT) in 13 eyes of 13 patients who underwent uneventful cataract surgery at Royal Glamorgan Hospital in Llantrisant. Investigators measured the CCT in both eyes of each patient 1 hour preoperatively and at 1 hour, 1 day and 1 week after surgery. The non-operated eyes served as the control group, according to the study.

Central corneal thickness averaged 550.34 µm preoperatively and increased by about 13.81% to 626.39 µm at 1 hour postop. At 1 day, CCT remained increased by about 6.44% and averaged 585.8 µm. By 1 week follow-up, however, CCT had decreased to average 553.8 µm, or about 0.57% higher than baseline, the authors reported.

For the control group, CCT remained within ±2 µm of preoperative measurements, they noted.

The study is published in the August issue of Journal of Cataract and Refractive Surgery.