Evaluation of corneal biomechanical properties using an ocular response analyser to examine aphakic and pseudophakic patients after congenital cataract surgery

Abstract

ABSTRACT.Purpose: We evaluated corneal biomechanical properties in aphakic and pseudophakic patients after congenital cataract surgery and compared the data with those of age-matched normal subjects. Methods: We included 43 eyes of 43 aphakic or pseudophakic patients treated via congenital cataract surgery. As controls, 42 healthy age-and sex-matched subjects were enrolled. After a complete ophthalmic examination, central corneal thickness (CCT) and intraocular pressure (IOP) were determined. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated IOP (IOPcc) and Goldmann-correlated IOP (IOPg) were recorded using an ocular response analyser. Results: In the study group, 18 eyes were aphakic and 25 eyes pseudophakic. We found a significant difference in CCT between the aphakic, pseudophakic and control groups (p < 0.001). No significant among-group differences were detected in CH or CRF (p > 0.05). We found significant differences in IOPcc, IOPg and IOP measured with Goldmann applanation tonometry (IOP GAT ) between the study and control groups (p < 0.001). In contrast, we found no significant differences within the two study groups in terms of these three IOP values (p > 0.05). Conclusion: Although CCT increased after congenital cataract surgery, corneal biomechanical parameters, including CH and the CRF, were not affected by such surgery. Determination of the IOPcc did not provide any additional information on true IOP, which was independent of CCT in both aphakic and pseudophakic patients after congenital cataract surgery.

Factors influencing intraocular pressure, corneal thickness and corneal biomechanics after congenital cataract surgery

“…In a recent study by the same group, the median CCT was significantly greater in aphakic eyes than in pseudophakic eyes or control eyes 9. Although they noted significant differences in CCT between pseudophakic eyes in which an IOL was implanted at the time of cataract surgery and pseudophakic eyes in which an IOL was implanted secondarily, they did not perform separate comparisons between these two subgroups and aphakic and normal eyes 9. Lupinacci et al 10 found that aphakic eyes treated with congenital cataract extraction had thicker corneas than normal phakic eyes and suggested that increases in CCT occur postoperatively.…”

“…This reduction, which was probably caused by the development of corneal structural changes, cannot be prevented or reversed by secondary IOL implantation. We are aware of only one study that evaluated corneal biomechanics after congenital cataract surgery 9. Simsek et al 9 reported that CH was lower in aphakic eyes than in pseudophakic eyes, although the difference between the two groups was of borderline significance.…”

“…We are aware of only one study that evaluated corneal biomechanics after congenital cataract surgery 9. Simsek et al 9 reported that CH was lower in aphakic eyes than in pseudophakic eyes, although the difference between the two groups was of borderline significance. They noted no significant difference in CRF among normal, aphakic and pseudophakic eyes.…”

“…Their pseudophakic group was small (IOLs were implanted in five eyes at the time of congenital cataract surgery and in five eyes secondarily) 8. In a recent study by the same group, the median CCT was significantly greater in aphakic eyes than in pseudophakic eyes or control eyes 9. Although they noted significant differences in CCT between pseudophakic eyes in which an IOL was implanted at the time of cataract surgery and pseudophakic eyes in which an IOL was implanted secondarily, they did not perform separate comparisons between these two subgroups and aphakic and normal eyes 9.…”

“…CCT has been studied extensively in patients who have undergone congenital cataract surgery 6–10. In contrast, there is only one study regarding corneal biomechanics following congenital cataract surgery 9. This study aimed to evaluate and compare IOP, CCT and corneal biomechanics among patients with aphakia, patients with pseudophakia and matched controls following congenital cataract surgery.…”