Combined Transepithelial Phototherapeutic Keratectomy and Corneal Collagen Cross-Linking for Progressive Keratoconus

Comparison of Combined Transepithelial Phototherapeutic Keratectomy and Mechanical Debridement During Corneal Cross-linking

“…Gaster et al used the VISX Star S4 excimer laser (Advanced Medical Optics, Santa Ana, CA), whereas we used the Allegretto WaveLight (WaveLight Laser Technologies, Erlangen, Germany); therefore, the different excimer laser platform could be another reason for the different results. 1,2 Since our first case in 2010, as Gaster et al also reported, all studies until now support the conclusion that transepithelial PTK during CXL is an effective and safe combined treatment for keratoconic patients. 1,2,[4][5][6] In our opinion, this combined technique (Cretan protocol) should be performed in any case of CXL aiming to better visual and refractive outcomes, especially in cases in which photorefractive keratectomy cannot be combined with CXL due to low corneal thickness.…”

“…1,2 Since our first case in 2010, as Gaster et al also reported, all studies until now support the conclusion that transepithelial PTK during CXL is an effective and safe combined treatment for keratoconic patients. 1,2,[4][5][6] In our opinion, this combined technique (Cretan protocol) should be performed in any case of CXL aiming to better visual and refractive outcomes, especially in cases in which photorefractive keratectomy cannot be combined with CXL due to low corneal thickness. Furthermore, the customization of transepithelial PTK and CXL and its parameters (ablation depth and zone of transepithelial PTK) according to the preoperative epithelial map and corneal profile of the patient with keratoconus could maximize the effect of this combined treatment.…”

“…1 As the authors reported, their results are in contrast with the ones in our relevant study, which was a prospective, comparative analysis of well-matched groups and showed that transepithelial PTK during CXL resulted in better visual and refractive outcomes in comparison with mechanical epithelial debridement. 2 A possible explanation for this discrepancy could be the difference in the preoperative maximum keratometry readings, which were higher in the PTK group of our case series (53.07 ± 7.20 diopters [D]) in comparison to the PTK group of Gaster et al's study (51.50 ± 5.00 D).…”

Update on Simultaneous Topo-guided Photorefractive Keratectomy Immediately Followed by Corneal Collagen Cross-linking for Treatment of Progressive Keratoconus

“…By taking advantage of the ability of the epithelium to smoothen the surface by being thinner in the apex of the cone, we can further improve the stromal surface and visual outcomes with PTK. 26 In addition, the topo-guided PRK is more accurately implemented in the stromal surface since the information of topography that are taken from the epithelium surface, correspond more accurately to the stromal surface. A significant debate in the literature is the use of MMC after the PRK procedure and prior to CXL.…”

Corneal Collagen Crosslinking Combined with Phototherapeutic Keratectomy and Photorefractive Keratectomy for Corneal Ectasia after Laser in situ Keratomileusis

“…However, visual recovery usually remains modest after CXL [5,6,7], despite the proven effectiveness in halting the progression of iatrogenic ectasia. Recently, the combination of CXL with photorefractive keratectomy (PRK) and phototherapeutic keratectomy (PTK) has offered exciting results in halting the progression of ectasia and providing visual improvement [8,9,10]. So far, there has been little research in simultaneous PTK-PRK-CXL applied for post-LASIK keratectasia.…”