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Purpose The purpose of this study is to assess the effect of various fluence levels on prophylactic corneal cross‐linking (CXL) combined with femtosecond laser in situ keratomileusis (FS‐LASIK‐Xtra) or transepithelial photorefractive keratectomy (TransPRK‐Xtra) on biomechanics, demarcation line (DL), and stromal haze. Methods Prospective analysis where two prophylactic CXL protocols (lower/higher fluence [LF/HF]: 30 mw/cm2, 60/80 s, 1.8/2.4 J/cm2) were performed as part of either an FS‐LASIK‐Xtra or TransPRK‐Xtra procedure. Data were collected preoperatively and at 1 week and 1, 3, and 6 months postoperatively. Main outcome measures were (1) dynamic corneal response parameters and the stress–strain index (SSI) from Corvis, (2) actual DL depth (ADL), and (3) stromal haze on OCT images analysed by a machine learning algorithm. Results Eighty‐six eyes from 86 patients underwent FS‐LASIK‐Xtra‐HF (21 eyes), FS‐LASIK‐Xtra‐LF (21 eyes), TransPRK‐Xtra‐HF (23 eyes), and TransPRK‐Xtra‐LF (21 eyes). SSI increased similarly by around 15% in all groups 6 months postoperatively (p = 0.155). All other corneal biomechanical parameters were statistically significant worsening postoperatively, but the change was similar in all groups. At 1 month postoperatively, there was no statistical difference in mean ADL among four groups (p = 0.613), mean stromal haze was similar between the two FS‐LASIK‐Xtra groups, but higher in the TransPRK‐Xtra‐HF group compared with the TransPRK‐Xtra‐LF group. Conclusions FS‐LASIK‐Xtra and TransPRK‐Xtra lead to a similar ADL and improve SSI equally. Lower fluence prophylactic CXL might be recommended as it achieves similar mean ADL with potentially less induced stromal haze, especially in TransPRK. The clinical relevance and applicability of such protocols remains to be assessed.

We aimed to evaluate the depth of the demarcation line following accelerated epithelium-off corneal cross-linking (A-CXL) performed at the slit lamp with the patient sitting in an upright position. Twenty-three eyes from twenty patients, undergoing epi-off A-CXL (9 mW/cm2 for 10 min) using a CXL device at the slit lamp in the upright position. Demarcation line depth was assessed at 1 month after the procedure using anterior segment optical coherence tomography (AS-OCT) and specialized software. Surgery was uneventful in all cases. The average postoperative demarcation line depth achieved was 189.4 µm (standard deviation: 58.67 µm). The demarcation line depth achieved with patients sitting upright, receiving CXL at the slit lamp, is similar to published data on CXL performed in the supine position, suggesting that demarcation line depth is not dependent on patient orientation during CXL.

PURPOSE: To present a case of epithelial ingrowth under a laser in situ keratomileusis (LASIK) flap as a direct result of a pressure shockwave without direct blunt trauma to the eye. METHODS: Case report RESULTS: A 27-year-old woman developed epithelial in-growth under the LASIK flap interface after a massive shock-wave trauma to the eye caused by the 2020 Port of Beirut explosion. No flap dislocation, folds, or tears had been noted on examination after the trauma. Observation with close follow-up was elected. The vision and area of ingrowth remained stable over 1 year of follow-up. CONCLUSIONS: Pressure shockwave from an immense blast can mimic direct blunt trauma in eyes after LASIK and can result in epithelial ingrowth. Treatment should be tailored to vision, flap condition, and progression. [J ournal of Refractive Surgery Case Reports. 2022;2(2):e26–e28.]

A symptomatic 51-year-old man was referred for therapeutic visual rehabilitation. He presented with compromised vision, high hyperopia, flat cornea, and a history of RK.