Abdel Megid Tag El Din, A. (2018). Variations of Corneal Hysteresis in Myopic Patients with Normal Pentacam Findings. The Egyptian Journal of Hospital Medicine, 71(5), 3131-3135.
Amr Esam Ali, Ahmed Youssef, Abdel Megid Tag El Din. "Variations of Corneal Hysteresis in Myopic Patients with Normal Pentacam Findings". The Egyptian Journal of Hospital Medicine, 71, 5, 2018, 3131-3135.
Abdel Megid Tag El Din, A. (2018). 'Variations of Corneal Hysteresis in Myopic Patients with Normal Pentacam Findings', The Egyptian Journal of Hospital Medicine, 71(5), pp. 3131-3135.
Abdel Megid Tag El Din, A. Variations of Corneal Hysteresis in Myopic Patients with Normal Pentacam Findings. The Egyptian Journal of Hospital Medicine, 2018; 71(5): 3131-3135.
Variations of Corneal Hysteresis in Myopic Patients with Normal Pentacam Findings
Al Hussein University Hospital, Al Azhar University, Cairo governorate, Egypt
Abstract
Background: hysteresis refers to the energy lost during the stress/strain cycle which is the result of viscous damping in the corneal tissue, is an indicator of corneal biomechanical properties. Refractive surgery currently uses corneal thickness as a basic qualification and planning parameter. However, corneal hysteresis may be more useful as a qualification factor for LASIK, a significant decrease in the IOP and biomechanical properties is found in eyes following LASIK surgery Objective: this study aimed to reveal the variations of corneal hysteresis in patients with normal pentacam findings and to see if a correlation exists between corneal hysteresis, corneal resistance factor, mean keratometric reading, central corneal thickness and anterior chamber depth during the pre-operative assessment of myopic patients going for LASIK. Patients and methods: in this study we did an analysis of corneal hysteresis in a group of myopic patients with normal pentacam findings undergoing evaluation for refractive surgery. In our study we included 50 eyes of 26 patients aged between 18 and 44.Results: this study included a mean keratometric reading of 44.108 D± 1.3243D, the mean central corneal thickness was 522.1um±38.416um, the mean anterior chamber depth was 3.2098mm±0.249mm the mean corneal hysteresis was 9.582 mmHg±1.4702 and the mean corneal resistance factor was 9.64 mmHg ±1.9838.Conclusion: our data suggested that patients should get their corneal hysteresis tested as a part of their routine investigation portfolio before undergoing refractive surgery as it may play a role in determining patients that are at higher risk of developing ectasia after surgery.