Efficacy and safety of small-incision corneal intrastromal lenticule implantation for hyperopia correction: a systematic review and meta-analysis.

Purpose: To assess the efficacy and safety of intrastromal lenticule implantation for the treatment of hyperopia. Methods: A systematic search of PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Internet, and Wan Fang Database identified studies on small-incision intrastromal lenticule implantation for hyperopia correction until January 2023. The Joanna Briggs Institute (JBI) critical appraisal tool was used to assess the quality of the retrospective research, and the Methodological Index for Non-randomized Studies (MINORS) was used to assess the quality of the prospective research. This study included postoperative visual outcomes, corneal morphology, and biomechanical outcomes. Results: A total of 456 articles were identified, of which 10 were included in the meta-analysis. Ten single-arm studies involving 190 eyes were included. A meta-analysis demonstrated that corneal intrastromal lenticule implantation treatment significantly improved hyperopia. Uncorrected distance visual acuity (UDVA) significantly improved compared to the preoperative value (p = 0.027), corrected distance visual acuity showed no difference compared to the preoperative value (p = 0.27), and 87% eyes have no loss of one or more lines in the Snellen lines of CDVA (p < 0.00001). There was a significant difference between the spherical equivalent refractive (SE) and preoperative examination (p < 0.00001), 52% of eyes had ±0.5 diopters (D) postoperative SE (p < 0.00001), and 74% eyes had ±1.0 D postoperative SE (p < 0.00001). The central corneal thickness (CCT) increased by 72.68 µm compared to that preoperatively (p < 0.00001), and corneal curvature increased by 4.18D (p < 0.00001). The Q-value decreased by 0.82 (p < 0.00001), and higher-order aberration (HOA) decreased by 0.66 (p < 0.00001). Conclusion: Small-incision intrastromal lenticule implantation may be an effective solution for correcting hyperopia. The effect of improved vision is significant, but further exploration is needed for changes in corneal biomechanics and long-term safety.Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42023432343.

[Clinical results of femtosecond laser assisted lamellar keratoplasty].

OBJECTIVE: To report the clinical results of femtosecond laser assisted lamellar keratoplasty (FS-LK). METHODS: Retrospective study. Twenty eyes of 17 patients who were treated with FS-LK were enrolled in this study. The preoperative visions were from 0.02 to 0.4. During the operation, the grafts were prepared with a depth of 400-600 µm according to the character of the affections. RESULTS: During the follow-up period, the visions of 18 eyes (90%) were better than preoperative ones. One of them was equal to 0.8. The best corrected visual acuities of 18 eyes (90%) were better than or equal to 0.5, one of which was 1.0. The astigmatisms of 15 eyes were under 3.00 diopters at one year after operation. During the operation of two cases, the paracentral cut occurred. Two patients experienced corneal opacity, and two cases had high astigmatisms after operation. Only one eye experienced immune rejection at one year after operation. CONCLUSIONS: The FS-LK appears to be a good alternative surgical method for patients with corneal diseases because of the great manipuility and excellent postoperative results, but more research is needed.

[Non-Descemet stripping automated endothelial keratoplasty for graft failure after penetrating keratoplasty].

OBJECTIVE: To report clinical results of non-Descemet stripping automated endothelial keratoplasty (nDSAEK) to treat graft failure after penetrating keratoplasty. METHODS: It was a retrospective case series study. Five cases of grafts failure after penetrating keratoplasty (PKP) were enrolled in this study. All patients had a cloudy and swollen grafts, which thicker than 620 µm, and had foreign body sensation, vision decrease. Of this 5 cases, 4 of them are pseudophakic eye, 1 is aphakic eye. One patient had previous vitrectomy, and 3 of them had one time history of PKP, 2 of them had twice PKP treatment. All cases were treated by nDSAEK, the nDSAEK grafts were prepared as a 200 µm thickness and 8.00 to 8.75 mm in diameter by using hand or femtosecond laser assisted methods. The graft was inserted by forceps or suture pulling method through a 5.00 mm scleral tunel incision. RESULTS: One graft dislocated at 1day postoperation, and was reattached by rebuble. All grafts keep clear during 8 - 28 months follow up period, and no immune rejection episodes were noted. The endothelial density were 865 to 2410/mm(2). Postoperative best corrected vision (pBCVA) are better or equal to previous BCVA after pkp. CONCLUSION: nDSAEK appears a good alternative surgical method for patients of grafts failure after pkp, especially for high risk patients of immune rejection.