PURPOSE: To investigate optical zone decentration following femtosecond laser–assisted lenticule intrastromal keratoplasty (FS-LIKE) or small incision lenticule intrastromal keratoplasty (SMI-LIKE) for correcting hyperopia. METHODS: This study analyzed decentration values obtained from optical coherence tomography (OCT) and tangential topography difference maps of 23 eyes (18 patients) undergoing FS-LIKE (n = 12) or SMI-LIKE (n = 11) via the concentric centration method. Total higher order aberrations (HOAs) and component aberrations were measured preoperatively and 6 months postoperatively. RESULTS: The mean optical zone decentration was 0.27 ± 0.08 and 0.39 ± 0.16 mm for the FS-LIKE and SMI-LIKE groups, respectively ( P = .039). A significant difference was noted in lenticule decentration between the two groups (0.18 vs 0.37 mm), whereas no significant difference was observed in stromal bed (pocket) decentration between the two groups (0.10 vs 0.12 mm). Six months after surgery, the spherical equivalent showed a reduction of 6.14 ± 2.44 and 6.10 ± 1.79 diopters (D) for the two groups, respectively ( P = .971), whereas the surgically induced astigmatism was 0.68 ± 0.49 and 1.56 ± 0.78 D for the two groups, respectively ( P = .004). Furthermore, induction of HOAs in the SMI-LIKE group was significantly larger than that in the FS-LIKE group ( P = .013). CONCLUSIONS: FS-LIKE can yield improved treatment centration and less induction of total HOAs. [ J Refract Surg . 2022;38(3):184–190.]

PurposeTo investigate the influence of keratometric astigmatism on visual outcomes following small incision lenticule extraction (SMILE).MethodsEighty eyes undergoing SMILE for myopia correction were classified into two groups based on preoperative keratometric astigmatism: low keratometric astigmatism (LA) and high keratometric astigmatism (HA) groups. Refractive outcomes, vector components, and changes in higher order aberrations (HOAs) were evaluated preoperatively and 6 months postoperatively.ResultsAt the postoperative 6-month visit, no significant difference was observed in the decentered distance between the HA and LA groups (HA: 0.17 ± 0.08 mm, LA: 0.16 ± 0.08 mm, P = 0.189). No significant differences in the correction index (P = 0.481), absolute angle of error (P = 0.104), or index of success (P = 0.147) were observed between the two groups. There was no significant difference in the induction of corneal aberrations between the two groups. Furthermore, there were no significant associations between the decentered distance and the vector components of astigmatic correction or induction of higher-order aberration in the HA group (P ≥ 0.294, P ≥ 0.112) or the LA group (P ≥ 0.323, P ≥ 0.080).ConclusionsSMILE for high keratometric astigmatism could achieve comparable treatment centration and visual quality to that of low keratometric astigmatism

Background To compare the changes in posterior corneal surface after small-incision lenticule intrastromal keratoplasty (SMI-LIKE) and femtosecond laser-assisted lenticule intrastromal keratoplasty (FS-LIKE) for hyperopia correction. Methods In this prospective comparative randomized study, 23 eyes with hyperopia were recruited. Eyes were categorized into two groups—SMI-LIKE group (11 eyes) and FS-LIKE group (12 eyes). Lenticules from myopia small incision lenticule extraction were implanted into a pocket (SMI-LIKE group) or at a depth of 100 µm under a flap (FS-LIKE group). Posterior corneal elevations in the center, mid-periphery, and periphery, as well as mean keratometry of the posterior corneal surface (Kmb) were measured using a Pentacam over a three-month follow-up. Results All surgeries were completed successfully and no complications occurred. At one day postoperatively, there was a slight backward change with SMI-LIKE and a forward change with FS-LIKE in the central region of the posterior corneal elevation. Conversely, the peripheral area showed forward displacement in SMI-LIKE and an apparent backward change in FS-LIKE. The mid-peripheral regions manifested a backward change after the procedure throughout the entire follow-up in both groups. Kmb exhibited flattening at one month postoperatively and subsequently returned to its original level at three months after SMI-LIKE while in FS-LIKE, Kmb steepened after lenticule implantation with a significant change noted at one day postoperatively (P = 0.001). Conclusions Posterior corneal surface after SMI-LIKE and FS-LIKE exhibited different change patterns in various corneal regions, with the most prominent change occurring at one day postoperatively during the three-month follow-up. Trial registration: Chinese Clinical Trial Registry: ChiCTR-ONC-16008300. Registered on Apr 18th, 2016. http://www.chictr.org.cn/edit.aspx?pid=14090&htm=4

PURPOSE: To describe the preliminary corrective results of treating hyperopia and hyperopic astigmatism with toric lenticule implantation. METHODS: A 23-year-old man presented with corneal scars and aphakia in the right eye. Manifest refraction was +10.00 −1.25 × 165° and plano in the right and left eyes, respectively. Owing to the patient's rigid gas permeable contact lens intolerance and other factors, an allogenic toric lenticule from a donor eye with a refractive power of −8.50 −1.25 × 5° was implanted. The lenticule (refraction = +9.75 −1.25 × 95°) was transferred onto the exposed stromal bed of the recipient's eye and aligned to the marking axis (refraction = +9.75 −1.25 × 165°). The correction index was calculated using the online Alpins Statistical System for Ophthalmic Refractive Surgery Techniques vector calculator. RESULTS: At 6 months postoperatively, refraction of the right eye was +3.00 −0.25 × 160°. Anterior corneal surface curvature and astigmatism changed from 42.90 diopters, 2.30 @ 48.00 to 49.10 diopters, 1.50 @ 90.00. Optical coherence tomography showed smooth attachment of the lenticule to the stromal layer with visible boundaries. CONCLUSIONS: Toric lenticule implantation was beneficial in treating traumatic hyperopia and hyperopic astigmatism. Further studies are required to assess the effectiveness of this technique. [ Journal of Refractive Surgery Case Reports . 2022;2(1):e1–e5.]