Aims This study aims to compare intraocular pressure (IOP), central corneal thickness (CCT) and corneal biomechanics among patients with aphakia, patients with primary and secondary pseudophakia and matched controls following congenital cataract surgery and to investigate the factors influencing these variables.

Methods This study included 36 aphakic eyes, 47 primary pseudophakic eyes and 30 secondary pseudophakic eyes. Thirty-four normal eyes of matched volunteers were recruited for comparisons. Postoperative IOP measured with a Goldmann applanation tonometer (IOP_GAT), CCT, corneal hysteresis (CH), corneal resistance factor (CRF) and cornea-compensated IOP (IOP_CC) were compared among the groups. Univariate analyses and multiple linear regression analyses were used to investigate the influences of independent factors on IOP_GAT, CCT, CH, CRF and IOP_CC, considering all the operated eyes as one group.

Results IOP_GAT was 12.5±0.92, 14.7±1.9, 13.4±2.3 and 15.7±2.0 mm Hg in normal, aphakic, primary pseudophakic and secondary pseudophakic eyes, respectively (p<0.001). CCT was 559.5±42.7, 628.0±61.7, 566.8±35.3 and 585.2±41.1 µm, respectively (p<0.001). CH was 10.87±2.47, 10.42±2.20, 11.84±2.13 and 9.74±1.94 mm Hg, respectively (p=0.019). IOP_CC was 15.91±3.74, 18.40±4.35, 14.58±4.36 and 19.05±4.54 mm Hg, respectively (p<0.001). There was no significant difference in CRF among the groups (p=0.06). Regression analyses revealed that the type of operation was significantly associated with IOP_GAT (p=0.04), CCT (p<0.001) and CH (p=0.006).

Conclusions IOP_GAT, CCT, CH and IOP_CC were significantly different in treated eyes compared with normal eyes after congenital cataract surgery. These variables were primarily affected by the type of surgery. Primary intraocular lens implantation preserved corneal structure and function of the anterior chamber angle.