Author: M. Martinez
Co Author(s): R. Zafrilla Gomez, G. Bolivar De Miguel, J. Gros-Otero, C. Sanchez Barahona, M. Teus Guezala
To assess the impact of different amounts of postoperative corneal edema on corneal hysteresis, after uneventful cataract surgery.
Hospital Universitario Príncipe de Asturias, Alcalá de Henares, Madrid, Spain.
130 patients who underwent routine clear corneal phacoemulsification were evaluated. The central corneal thickness (CCT) was measured using ultrasound pachymetry, the corneal hysteresis (CH), IOPg and IOPcc were measured using the ORA device. Measurements were performed before surgery, and at postoperative days 1, 7 and 30. Patients were classified in Group I if the increase of CCT on day 1 after surgery was greater than 50µm (stromal edema) (44 eyes), or in group II if the increase of CCT after surgery was less than 50µm (no stromal edema) (86 eyes).
CH decreased after surgery in both groups, although the decrease was higher in group II (9.9±2.1, 8.2±3.1, 8.7±1.7 and 9.1±2.2) vs group I (9.9±2.6, 9.01±2.7, 9.1±2.05 and 9.4±3.07) at baseline, and in post-op days 1, 7 and 30 respectively. (p=0.02). The IOP in group I was 17.3±4mmHg (IOPcc) and 16.2±4.4mmHg (IOPg), while the IOP in the group II was higher, 24.5±10.1mmHg (IOPcc) and 22.4±9.5mmHg (IOPg) p=0.01.
The effect of postoperative IOP may be relevant on CH. CH decreased after cataract surgery in both groups, but the decrease was greater in the group with less corneal edema and higher IOP, than in the group with more corneal edema, so it seems that it is the IOP and not the amount of corneal edema the parameter that better explains the decrease of the CH after cataract surgery.