Comparison of Laser Platform Estimation and Objective Measurement of Maximum Ablation Depth Using Scheimpflug Pachymetry in Myopic Femtosecond Laser In Situ Keratomileusis. Issue 3 (March 2020)

• Record Type: Journal Article
• Authors: Febbraro, Jean-Luc; Picard, Hervé; Moran, Sarah; Grise-Dulac, Alice; Salomon, Laurence; Gatinel, Damien
• Is Part Of: Cornea. Volume 39:Issue 3(2020)
• Publication Date: 2020-03
• Subjects: LASIK -- ablation depth -- Scheimpflug pachymetry -- Pentacam; Cornea -- Periodicals; Cornea -- Periodicals; Cornée -- Périodiques; 617.719
• DOI: 10.1097/ICO.0000000000002143
• Languages: English
• ISSNs: 0277-3740

Abstract

Abstract : Purpose: To compare the preoperative estimation of maximum ablation depth provided by the laser platform with objective measurement using Scheimpflug pachymetry in myopic femtosecond laser-assisted in situ keratomileusis (FS-LASIK). Methods: This is a prospective study carried out at the Rothschild Foundation, Paris, France. In 89 consecutive myopic eyes (45 patients) treated with FS-LASIK, the maximum ablation depth was calculated by measuring the difference between preoperative and 3-month postoperative measurements in central corneal thickness using Scheimpflug pachymetry (Pentacam HR; Oculus Optikgeräte, Wetzlar, Germany). These values were compared with the preoperative estimation of the maximum ablation depth provided by the laser platform, without nomogram adjustment. Results: We found a strong linear correlation between laser platform estimation of maximum ablation depth and Scheimpflug pachymetry ( P < 0.00001). The mean ablation depth measured using Scheimpflug pachymetry was greater than that predicted by the laser platform, with a mean overall difference of 2.15 μm ( P < 0.05). Subgroup analysis revealed a difference in ablation depth measurements of 7.1 μm in the high myopia subgroup, which was the only subgroup where the difference remained statistically significant. Conclusions: In myopic FS-LASIK, laser platform estimation of maximum ablation depth correlates well with measurement of maximum ablation depth using Scheimpflug pachymetry and therefore can be used safely.