Small incision lenticule extraction (SMILE) surgery was developed in 2008 as an extension of the femtosecond lenticule extraction procedure. Over the years, SMILE has become a highly popular laser refractive surgery offering a minimally invasive alternative to LASIK for correcting myopia and myopic astigmatism. Despite its benefits such as a flapless femtosecond laser procedure with reduced corneal nerve disruption, the procedure's relative novelty necessitates standardization. Given the myriads of emerging information and variability, a panel of 22 international experts is formed by the Asia Pacific Myopic Society (APMS) and the Academy of Asia-Pacific Professors of Ophthalmology (AAPPO) to explore the controversy and to work out a consensus on SMILE. This consensus manuscript arises from a systematic exploration of current literature and is supported by the collective insights of international experts in the field of refractive surgery. The panel convened to review the issues, engage in discussion, develop proposals, and vote to establish consensus across four areas: 1) preoperative assessment, 2) preoperative surgical planning, 3) intraoperative considerations, and 4) postoperative management in a five-point Likert scale (strongly agree, agree, neutral, disagree and strongly disagree). Consensus was achieved when at least 75 % of the experts had voted for "strongly agree" or "agree" on the consensus statement concerned. 63 consensus statements were discussed, with 51 (81.0 %) statements reaching consensus. By establishing standardized consensus, this paper aims to reduce variability and enhance predictability and safety in refractive outcomes. Ongoing research is encouraged on issues where consensus could not be reached among the international panel of experts (IPE).

To evaluate the effects of different programmed optical zones (POZs) on achieved corneal refractive power (CRP) with myopic astigmatism after small incision lenticule extraction (SMILE). In total, 113 patients (113 eyes) were included in this retrospective study. The eyes were divided into two groups according to POZ: group A (6.5, 6.6, and 6.7 mm, n = 59) and group B (6.8, 6.9, and 7.0 mm, n = 54). Fourier vector analysis was applied to evaluate the error values between the attempted and achieved corneal refractive power (CRP). Alpins vector analysis was used to calculate surgically induced astigmatism (SIA), difference vector (DV), magnitude of error (ME), and astigmatism correction index (ACI). Multivariate regression analysis was performed to assess potential factors associated with the error values. The error values in the group with large POZ were closer to zero, and significantly associated with the POZ at 2 and 4 mm of the cornea (β =  − 0.50, 95% confidence interval [CI] [− 0.80, − 0.20]; β =  − 0.37, 95% CI [− 0.63, − 0.10], P < 0.05, respectively). For the correction of astigmatism, the values of SIA, ME, and ACI were lower in group B than in group A (P < 0.05). The fitting curves between TIA and SIA were y = 0.83x + 0.19 (R2 = 0.84) and y = 1.05x + 0.04 (R2 = 0.90), respectively. Smaller POZs resulted in higher error values between the achieved- and attempted-CRP in the SMILE procedure, which should be considered when performing surgery.

PurposeWe aim to investigate the effect of sustained hyperglycemia on corneal epithelial wound healing, ocular surface and systemic immune response, and microbiome indices in diabetic mice compared to controls after alkaline chemical injury of the eye. MethodsCorneal alkaline injury was induced in the right eye of Ins2(Akita) (Akita) mice and wild-type mice. The groups were observed at baseline and subsequently days 0, 3, and 7 after injury. Corneal re-epithelialization was observed under slit lamp with fluorescein staining using a cobalt blue light filter. Enucleated cornea specimens were compared at baseline and after injury for changes in cornea thickness under hematoxylin and eosin staining. Tear cytokine and growth factor levels were measured using protein microarray assay and compared between groups and time points. Flow cytometry was conducted on peripheral blood and ocular surface samples to determine CD3+CD4+ cell count. Fecal samples were collected, and gut microbiota composition and diversity pattern were measured using shotgun sequencing. ResultsAkita mice had significantly delayed corneal wound healing compared to controls. This was associated with a reduction in tear levels of vascular endothelial growth factor A, angiopoietin 2, and insulin growth factor 1 on days 0, 3, and 7 after injury. Furthermore, there was a distinct lack of upregulation of peripheral blood and ocular surface CD3+CD4+ cell counts in response to injury in Akita mice compared to controls. This was associated with a reduction in intestinal microbiome diversity indices in Akita mice compared to controls after injury. Specifically, there was a lower abundance of Firmicutes bacterium M10-2 in Akita mice compared to controls after injury. ConclusionIn diabetic mice, impaired cornea wound healing was associated with an inability to mount systemic and local immune response to ocular chemical injury. Baseline and post-injury differences in intestinal microbial diversity and abundance patterns between diabetic mice and controls may potentially play a role in this altered response.

Purpose:To analyze the 5-year results of accelerated corneal collagen crosslinking (CXL) for progressive keratoconus and identify preoperative characteristics predictive of visual and topographic outcomes. Methods:A prospective interventional case series. Nineteen eyes of 19 patients receiving accelerated CXL with settings of 18 mW/cm2 for 5 min were included. Clinical and topographic parameters were assessed. Linear regression and logistic regression were used to compare the R2 and odds ratio (OR), respectively, between baseline characteristics and postoperative outcomes. Results:Corrected distance visual acuity (CDVA) remained stable from 0.28 ± 0.21 to 0.25 ± 0.18 logMAR (P = 0.486). The mean cylindrical refraction was stable (P = 0.119). The maximal keratometry (Kmax) decreased from 61.99 ± 10.37 to 59.25 ± 7.75 D (P < 0.001), flattening in the flattest and steepest meridians and mean keratometry were also observed (P ≤ 0.040). The mean anterior elevation at the apex reduced from 21.42 ± 16.69 to 18.53 ± 12.74 μm (P = 0.013) and changes in posterior elevation were non-significant (P = 0.629). Preoperative Kmax best predicted the postoperative change in Kmax (R2 = 0.55, P < 0.001) compared to the other baseline characteristics (P ≤ 0.028), whereas preoperative CDVA was the only significant predictor of postoperative change in CDVA (R2 = 0.41, P = 0.003). Accelerated CXL is less likely to fail in eyes with a steeper preoperative Kmax (OR = 0.74, P = 0.040) or greater posterior elevation at the apex (OR = 0.91, P = 0.042). Conclusion:Kmax significantly decreased following accelerated CXL. Eyes with worse preoperative CDVA and higher Kmax were more likely to have an improvement in visual acuity and corneal flattening.

Aim To compare the safety, efficacy, and predictability outcomes of combined sub-Bowman's keratomileusis (thin flap laser in situ keratomileusis [LASIK]) and accelerated crosslinking (CXL) using two different irradiation durations. Methods A retrospective comparative study of patients with percent tissue altered >= 35%, undergoing simultaneous CXL during sub-Bowman's keratomileusis were recruited. Following riboflavin application, they underwent ultraviolet-A (UVA) irradiation (18 mW/cm(2)) for either 2 min (total energy 2.16 J/cm(2)) or 3 min (total energy 3.24 J/cm(2)). Visual and refractive outcomes were compared between follow-up visits during the first year postoperatively. Demarcation line and endothelial cell count were evaluated, respectively, at 1 and 3 months postoperatively. Results The baseline characteristics were similar between the 40 eyes/patients treated using the 2-min protocol and the 33 eyes/patients treated with the 3-min protocol (p >= .114). Uncorrected distance visual acuity and corrected distance visual acuity were significantly better for eyes treated with the shorter irradiation protocol on Day 1 (p <= .030) and Month 1 (p <= .040) postoperatively; these differences diminished by Month 3 (p >= .070). Likewise, the efficacy index was higher during the first postoperative week for the 2-min protocol (p <= .043). At 1 year, the proportion of eye attaining within 0.5 D of target refraction was 80.0% and 84.8% for the 2-min and 3-min protocols, respectively (p = .590). The corresponding corneal stromal demarcation line depth and endothelial cell density changes were comparable between the two groups (p = .311 and 0.899, respectively). Conclusions A comparable volume of crosslinked corneal tissue can be achieved by using a shorter UVA irradiation duration. Additional duration of UVA irradiation could lead to delay in visual rehabilitation after simultaneous sub-Bowman's keratomileusis and CXL.

center dot PURPOSE: To optimize artificial intelligence (AI) algo-rithms to integrate Scheimpflug-based corneal tomogra-phy and biomechanics to enhance ectasia detection.center dot DESIGN: Multicenter cross-sectional case-control ret-rospective study.center dot METHODS: A total of 3886 unoperated eyes from 3412 patients had Pentacam and Corvis ST (Oculus Op-tikgerate GmbH) examinations. The database included 1 eye randomly selected from 1680 normal patients (N) and from 1181 "bilateral" keratoconus (KC) patients, along with 551 normal topography eyes from patients with very asymmetric ectasia (VAE-NT), and their 474 unoperated ectatic (VAE-E) eyes. The current TBIv1 (tomographic-biomechanical index) was tested, and an optimized AI algorithm was developed for augmenting accuracy.center dot RESULTS: The area under the receiver operating char-acteristic curve (AUC) of the TBIv1 for discriminating clinical ectasia (KC and VAE-E) was 0.999 (98.5% sen-sitivity; 98.6% specificity [cutoff: 0.5]), and for VAE-NT, 0.899 (76% sensitivity; 89.1% specificity [cutoff: 0.29]). A novel random forest algorithm (TBIv2), devel-oped with 18 features in 156 trees using 10-fold cross -validation, had a significantly higher AUC (0.945; De -Long, P < .0001) for detecting VAE-NT (84.4% sen-sitivity and 90.1% specificity; cutoff: 0.43; DeLong, P < .0001) and a similar AUC for clinical ectasia (0.999; DeLong, P = .818; 98.7% sensitivity; 99.2% specificity [cutoff: 0.8]). Considering all cases, the TBIv2 had a higher AUC (0.985) than TBIv1 (0.974; DeLong, P < .0001).center dot CONCLUSIONS: AI optimization to integrate Scheimpflug-based corneal tomography and biome-chanical assessments augments accuracy for ectasia detection, characterizing ectasia susceptibility in the diverse VAE-NT group. Some patients with VAE may have true unilateral ectasia. Machine learning consider-ing additional data, including epithelial thickness or other parameters from multimodal refractive imaging, will con-tinuously enhance accuracy. NOTE: Publication of this article is sponsored by the American Ophthalmological Society. (Am J Ophthalmol 2023;251: 126-142. (c) 2023 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ))

To compare intrasession agreement and repeatability of wavefront aberration measurements from three different aberrometers obtained using Hartmann–Shack, ray tracing and automated retinoscopy methods, as well as their interdevice agreement.

To evaluate the repeatability and agreement of corneal and biometry measurements obtained with two swept-source optical coherence tomography (SSOCT) and a partial coherence interferometry-based device. This is a cross-sectional study. Forty-eight eyes of 48 patients had three consecutive measurements for ANTERION (Heidelberg Engineering, Germany), CASIAII (Tomey, Japan) and IOLMaster500 (Carl Zeiss Meditec, USA) on the same visit. Mean keratometry (Km), central corneal thickness (CCT), anterior chamber depth (ACD) and axial length (AL) were recorded. Corneal astigmatic measurements were converted into vector components—J0 and J45. Intra-device repeatability and agreements of measurements amongst the devices were evaluated using repeatability coefficients (RCs) and Bland–Altman plots, respectively. All devices demonstrated comparable repeatability for Km (p ≥ 0.138). ANTERION had the lowest RC for J0 amongst the devices (p ≤ 0.039). Systematic difference was found for the Km and J0 obtained with IOLMaster500 compared to either SSOCTs (p ≤ 0.010). The ACD and AL measured by IOLMaster500 showed a higher RC compared with either SSOCTs (p < 0.002). Systematic difference was found in CCT and ACD between the two SSOCTs (p < 0.001), and in AL between ANTERION and IOLMaster500 (p < 0.001), with a mean difference of 1.6 µm, 0.022 mm and 0.021 mm, respectively. Both SSOCTs demonstrated smaller test–retest variability for measuring ACD and AL compared with IOLMaster500. There were significant disagreement in keratometry and AL measurements between the SSOCTs and PCI-based device; their measurements should not be considered as interchangeable.