Évolution de l'astigmatisme après ablation d'une suture cornéenne pour chirurgie de la cataracte

SummaryPurpose To evaluate the time until astigmatic stabilization after corneal suture removal after cataract surgery. Methods A prospective study was performed on 13 patients who had undergone cataract surgery by phacoemulsification with 2.4 mm incision, for whom it was felt necessary to remove a corneal suture. A specular corneal topography was performed by OPD Scan before removal, immediately after, then 10, 20, 30 minutes and 15 days later. For each acquisition, the keratometric readings at the steepest (Kmax) and the flattest (Kmin) meridians (central at 1.15 mm from corneal center, intermediate at 2.30 mm and peripheral at 3.30 mm) and the amount of corneal astigmatism were measured. Results Corneal topography of 13 patients was acquired. Mean age was 70 ± 12 years. Mean time after cataract surgery was 23 ± 14 days. The greatest change in Kmax occurred within the first minutes following suture removal for the central and intermediate cornea (mean variation of -4.38% and -4.59% of initial Kmax respectively, i.e. -2.04 D ± 3.14 D et -2.15 D ± 3.11 D) whereas it was observed between 0 and 10 minutes for the peripheral area (mean 1.57% of Kmax after suture removal i.e. 0.96 D ± 1.85 D). Mean change in corneal astigmatism between 30 minutes and day 15 was 0.08 D ± 0.31 D (3.6% of baseline). When suture removal was performed between 7 and 10 days postoperatively, mean change was 0.16 D ± 0.24 D, whereas it was 0.03 D ± 0.34 D when performed after four weeks. Conclusion Keratometric readings vary only slightly beyond the first 30 minutes after suture removal. These results suggest that the refraction could be accurately measured the same day as suture removal, with no additional follow-up absolutely necessary in order to prescribe the final spectacles.