Purpose: To systematically evaluate and compare the effectiveness and safety of small incision lenticule extraction (SMILE), laser in situ keratomileusis (LASIK), and photorefractive keratectomy (PRK) for myopic correction through thorough synthesis of contemporary evidence. Methods: Systematic review was conducted following PRISMA guidelines. Comprehensive scarches were performed in PubMed/MEDLINE, Embase, Cochrane Library, Web of Science and Scopus from January 2020 to December 2025. Eligible studies included randomized controlled trials, prospective comparative studies, retrospective comparative studies, and meta- analysis comparing at least two of the three techniques for myopic correction with minimum 6-month follow-up. Primary outcomes included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refractive predictability (+0.50 D and +1.OO D), efficacy index and safety index. Secondary outcomes encompassed intraoperative and postoperative complications, corneal ectasia, contrast sensitivity, higher-order aberrations (coma, spherical aberration, total HOAs), and dry eye parameters (tear break-up time, Schirmer test, Ocular Surface Disease Index). Results: From 1,034 initially identified records, 230 unique studies underwent full-text review, with 30 studies meeting inclusion criteria for qualitative synthesis. AlI techniques achieved excellent visual outcomes with efficacy indices 0.94 and comparable postoperative UDVA and CDVA SMILE produced significantly larger effective optical zones (22.18 + 2.61 mm) compared to LASIK (19.54 + 1.44 mm) and PRK (19.39 + 1.66 mm), correlating with reduced spherical aberration induction. Post-refractive ectasia incidence without identifiable preoperative risk factors was lowest for SMILE (11 per 100.000 eyes), followed by PRK (20 per 100.000), and highest for LASIK (90 per 100.000), with LASIK demonstrating 4.5-fold higher risk than PRK Dry eye symptoms were most pronounced following LASIK due to extensive corneal nerve disruption, while SMILE showed superior preservation of corneal biomechanical integrity. Conclusions: SMILE, LASIK, and PRK achieve comparable refraction results for myopic correction with efficacy indices exceeding 0.94 across all modalities However SMILE offers distinct advantages including larger effective optical zones, reduced higher-order aberration induction, lower ectasia risk and better preservation of corneal biomechanics and tear film stability: LASIK remains associated with higher ectasia rates and more pronounced dry eye symptoms PRK demonstrates intermediate safety profiles with prolonged visual recovery. Technique selection should be individualized based on preoperative corneal parameters, refraction error magnitude, patient occupation, and risk tolerance for specific complications.

Purpose: This study reports a case of a large incisional tear caused by abrupt Bell’s phenomenon during pocket irrigation in femtosecond laser-assisted small incision lenticule extraction (SMILE).Case summary: A 28-year-old male patient underwent SMILE surgery. During pocket irrigation of the right eye, Bell’s phenomenon suddenly occurred, resulting in a large inferior arcuate extension of the incision that reached the inferior cap margin. After confirming wound integrity and the absence of additional tissue damage, a bandage contact lens was applied. On postoperative day 7, the incision was self-sealed with intact wound integrity. Three months postoperatively, uncorrected distance visual acuity was 20/20 in both eyes. The right cornea remained stable, although a faint residual scar was observed at the site of the incisional tear.Conclusion: Abrupt eye movements during pocket irrigation in SMILE can cause large incisional tears. Surgeons should exercise heightened vigilance during irrigation, particularly in anxious or uncooperative patients, to prevent such complications.

PurposeThis meta-analysis aimed to evaluate the studies comparing transepithelial photorefractive keratectomy (TransPRK) to LASIK (Laser-Assisted In Situ Keratomileusis)/SMILE (Small Incision Lenticule Extraction) in terms of visual outcomes for myopia, astigmatism and hyperopia.MethodsStudies from PubMed® were included based on predefined criteria comparing TransPRK to LASIK/SMILE in terms of efficacy, efficacy index, safety, safety index, predictability, correction index, difference vector or index of success. A random-effects meta-analysis provided standardized mean differences, odds ratios (OR) and 95% confidence intervals (CI).Results17 studies with 5686 treated eyes met the inclusion criteria. Compared to LASIK, TransPRK showed a log(OR) of 0.09 (CI: -0.34 to 0.52) for efficacy, -0.85 (CI: -1.40 to -0.31) for safety (favoring LASIK) and 0.08 (CI: -0.28 to 0.44) for predictability. Compared to SMILE, TransPRK had a log(OR) of 0.77 (CI: -0.29 to 1.84) for efficacy, -0.3 (CI: -2.27 to 1.67) for safety and -0.91 (CI: -1.82 to 0) for predictability.ConclusionNo statistically significant differences were found between TransPRK and LASIK/SMILE in terms of efficacy and predictability. LASIK did show a significant safety advantage compared to TransPRK (negative log[OR], p < 0.05) in the astigmatism and low-to-moderate myopia subgroup but the safety index did not. Procedure choice should be based on patient characteristics, laser availability, complication risk and surgeon experience, and not by performance in efficacy, safety or predictability While LASIK has a lower incidence of haze formation and SMILE offers a better biomechanical stability, TransPRK remains a suitable option especially in the hands of a less experienced surgeon.

This study evaluated the early outcomes of hyperopic small incision lenticule extraction (SMILE) using the VisuMax 800 femtosecond laser in a Korean cohort, focusing on safety, efficacy, refractive predictability, and centration accuracy. This retrospective study included 11 eyes from 7 patients who underwent hyperopic SMILE using the VisuMax 800 between December 1, 2024, and October 31, 2025, at Onnuri Eye Hospital in Jeonju, Korea. All eyes completed at least 3 months of postoperative follow-up. Preoperative and postoperative evaluations included uncorrected and corrected distance visual acuity (UDVA and CDVA), manifest refraction, tomography, and wavefront aberrometry. Outcomes were analyzed using the standard nine graphs for refractive surgery. Astigmatic changes were assessed using the Alpins vector method. Optical zone decentration was calculated using postoperative Placido-Scheimpflug topography. The median preoperative spherical equivalent (SEQ) was +2.50 D [interquartile range (IQR), 1.94 to 4.12]. At 3 months, eight eyes (72.7%) were within ±0.50 D and all eyes (100%) were within ±1.00 D of the residual SEQ. The median efficacy index was 0.90 (IQR, 0.80 to 0.95). CDVA was unchanged in 63.6% of eyes and decreased by one line in 36.4%; no eye lost two or more lines. The median safety index was 0.86 (IQR, 0.80-1.00). RMS higher-order aberrations increased by +0.38 μm (IQR, 0.09 to 0.52). The median vertex-based decentration was 0.064 mm (IQR, 0.036 to 0.091). Decentration demonstrated a significant positive correlation with RMS HOA (ρ = 0.709, p = 0.014). Hyperopic SMILE using the VisuMax 800 produced favorable early clinical outcomes with high centration accuracy as well as shorter surgical time. Larger prospective studies with longer follow-up are necessary to determine long-term stability.

Corneal stromal lenticules obtained through small incision lenticule extraction (SMILE) procedures offer a valuable graft material for therapeutic applications. Current clinical utilization faces challenges due to intrinsic thinness (<140 μm) and restricted dimensions (generally around 6.6 mm). This study introduced a novel approach to enable the construction of customizable corneal grafts by stacking lenticules, achieving specific thickness and diameter for diverse corneal defects, using photo-crosslinked dual-network hydrogels based on methacrylated gelatin (GelMA). In vitro characterization confirmed the hydrogel’s suitable morphological architecture, optical clarity, and excellent biocompatibility, establishing it as an optimal biological adhesive for sutureless graft implantation. This multi-lenticule encapsulation strategy using the hydrogels successfully reconstructed experimental rabbit corneal defects (7.0-mm diameter) in vivo. Over a 5-week postoperative period, the hydrogel demonstrated controlled biodegradation while maintaining structural integrity and optical functionality throughout tissue remodeling. It effectively adhered to the surrounding stromal tissues and supported epithelial regeneration over the transplanted grafts. The study demonstrates sutureless-free corneal stromal lenticule implantation, enabled by the GelMA-based photocrosslinked dual-network hydrogel, addressed the limitations of individual SMILE lenticules. The GelMA-based photocrosslinked dual-network hydrogel serves as both a biocompatible adhesive for multi-lenticule implantation and an optimal functional material for reconstructing corneal defects.

Refractive surgery may exacerbate the existing dry eye symptoms in patients with dry eye syndrome. Therefore, we explore the therapeutic and protective effects of using optimal intense pulsed light (IPL) therapy combined with meibomian gland expression (MGX) before and after surgery on post-laser corneal refractive surgery dry eyes. This was a prospective, self-controlled, single-center clinical trial. Using optimal IPL therapy and MGX, a total of 68 patients with mild-to-moderate evaporative dry eye or meibomian gland dysfunction who underwent refractive surgery received 2 sessions of treatment. The treatment was administered once a week preoperatively and once a week postoperatively. Baseline measurements were taken before optimal IPL therapy and MGX, and the parameters were assessed at 1 week and 1 month after surgery. Out of 68 patients, 54 patients received small-incision lenticule extraction (SMILE), while 14 patients received femtosecond laser-assisted in situ keratomileusis (FS-LASIK) (results primarily reflect SMILE outcomes due to sample imbalance). In the SMILE group, significant improvement was already observed in uncorrected/corrected distance visual acuity (P = 1.42 × 10-3), meibomian gland expressibility score (MGYSS) (P = 0.01), and meibum yielding secretion score (MGS) (P = 5.39 × 10-4) between 1 week before and after the surgery. First noninvasive breakup time (NIBUTf) (P = 8.98 × 10-3), average noninvasive breakup time (NIBUTav) (P = 2.30 × 10-4), and meibomian gland dropout score (bottom) (P = 9.05 × 10-3) were observed to have significant improvement till 1 month after the surgery. Patients in the FS-LASIK group exhibited a comparable trend of change. IPL treatment combined with MGX may improve ocular discomfort and dry eye symptoms in MGYSS, MGS, NIBUTf, NIBUTav, and meibomian gland dropout score (bottom) for patients with post-laser corneal refractive surgery dry eyes in short term.

To compare visual, refractive, and vector-based astigmatic outcomes between Small Incision Lenticule Extraction (SMILE) and toric Implantable Collamer Lens (ICL) implantation in patients with myopic oblique astigmatism. In this retrospective, matched cohort study, 140 eyes (70 SMILE, 70 toric ICL) with oblique astigmatism were treated at a single center. Groups were matched preoperatively for refractive cylinder and spherical equivalent within ± 0.50 D. Postoperative outcomes at six weeks were assessed, including uncorrected and corrected distance visual acuity (UDVA, CDVA), spherical equivalent (SEQ), astigmatism correction using vector analysis (Alpins method), and safety and efficacy indices. A post hoc power analysis was performed for the astigmatic correction index. The efficacy index was 0.97 ± 0.17 in the ICL group and 0.94 ± 0.15 in the SMILE group. The safety index was 1.02 ± 0.11 (ICL) versus 1.01 ± 0.09 (SMILE). UDVA equal to or better than preoperative CDVA was achieved in 83% of ICL eyes and 79% of SMILE eyes. SEQ within ± 0.50 D was observed in 85.7% (ICL) versus 81.4% (SMILE). The astigmatic correction index was 0.97 for ICL and 1.04 for SMILE. Linear regression showed stronger correlation between target and achieved astigmatism in the ICL group (slope = 1.04, R2 = 0.77) compared to SMILE (slope = 0.76, R2 = 0.67). Power analysis confirmed 80.5% power to detect clinically meaningful differences. Both SMILE and toric ICL are effective and safe for correcting myopic oblique astigmatism. However, toric ICL demonstrated slightly greater precision in axis alignment and refractive predictability, supporting its use in cases of high oblique astigmatism where rotational accuracy is critical.

Orthokeratology (OK) has been widely adopted as a non-surgical intervention to slow myopia progression in children and adolescents. In China, where myopia prevalence is exceptionally high, OK lenses are commonly prescribed to school-aged children as an early intervention strategy. As these individuals reach adulthood, many pursue permanent refractive correction-such as small-incision lenticule extraction (SMILE)-to meet unaided visual acuity standards required for university entrance, military service, or certain occupations. However, the long-term morphological effects of OK wear and their potential impact on SMILE outcomes remain inadequately understood. This study aimed to evaluate ocular biometric and corneal morphological changes following long-term OK lens discontinuation and to compare the visual and surgical outcomes of SMILE between former OK users and spectacle-wearing controls. This retrospective comparative study included 44 myopic eyes-22 from patients with a history of OK lens wear (average duration: 64.8 ± 22.6 months; discontinuation ≥ 3 months) and 22 from age- and refractive error-matched controls. Examinations were conducted pre-OK (baseline), pre-SMILE, and at 1 month, 6 months, and final follow-up. Parameters included uncorrected and corrected distance visual acuity (UDVA, CDVA), corneal topography, pachymetry, volume, curvature, and higher-order aberrations. Astigmatic outcomes were evaluated using Alpins vector analysis. After OK discontinuation, the OK group exhibited increased corneal astigmatism (P = 0.030), spherical aberration (P = 0.036), and total aberrations (P = 0.034), as well as decreased vertical coma (P = 0.004), central corneal thickness (P < 0.001), and corneal volume (P = 0.001). Posterior corneal curvature steepened significantly (P < 0.001), while anterior curvature remained stable. Further correlation analysis showed that a younger age at initial OK lens wear was significantly associated with greater posterior steepening after discontinuation at the 3mm, 5mm, and 7mm zones (all P < 0.050). There was also a borderline negative correlation between the duration of OK lens wear and changes in posterior steep K value, suggesting longer wear may result in more pronounced steepening. At 6 months and final follow-up, both groups demonstrated comparable UDVA, CDVA, corneal shape, and higher-order aberrations (all P > 0.050). Vector analysis revealed no significant group differences in astigmatic correction. SMILE remains a viable option for former OK users; the observed reduction in CCT after lens discontinuation has minimal impact on refractive surgery selection.

PurposeTo compare the corneal spherical component (SC), regular astigmatism (RA), irregular astigmatism (IA, including asymmetry and irregularity), and visual quality 6 years after small incision lenticule extraction (SMILE) and laser subepithelial keratomileusis (LASEK) for mild‐to‐moderate myopia.MethodsThis retrospective, comparative study comprised the SMILE group (35 eyes) and LASEK group (36 eyes). Visual acuity, corneal topography utilizing swept‐source anterior segment OCT, and wavefront aberrations were recorded preoperatively and 6 years postoperatively. Fourier analysis of keratometric‐derived parameters of the anterior, posterior, and total cornea at 6 mm zone was evaluated.ResultsSix years postoperatively, the safety and efficacy indices were comparable between both groups. Fourier analysis revealed significant changes in SC decrease and asymmetry increase of the anterior and total cornea (p < 0.001), with LASEK exhibiting a more pronounced flattening effect of the anterior cornea (p = 0.001). Interestingly, RA of the anterior and total cornea decreased significantly after LASEK (p = 0.016, 0.002, respectively). Further linear correlation analysis showed that changes in SC (Δ SC) of anterior cornea and total cornea were correlated with the preoperative spherical power, mean refractive spherical equivalent (MRSE), lenticule thickness/ablation depth, ΔK1, and ΔK2 (all |r| > 0.85, p < 0.001). Compared with LASEK, SMILE induced less horizontal coma at 6 years postoperatively (p = 0.008).ConclusionsBoth SMILE and LASEK are safe and effective procedures for correction of mild‐to‐moderate myopia. LASEK demonstrates an advantage in flattening the anterior cornea and reducing regular astigmatism, while SMILE exhibits superior performance in inducing less horizontal comaTrial Registration: ClinicalTrials.gov identifier: NCT06673992

To develop and validate a machine learning system for the preoperative prediction of small effective optical zone (EOZ; diameter < 5.5 mm) after small incision lenticule extraction (SMILE). In this multicenter cohort study, 1030 multimodal combinations of preoperative parameters (PP), anterior corneal curvature maps (AACM), surgery video frames, and three-month postoperative EOZ diameter from 1030 eyes (634 patients) undergoing SMILE were divided: 677 for training, 85 for primary validation, 85 for internal test, and 183 for external test. The AACM-PP-Model integrating AACM and PP was developed and compared against parameter-only or image-only models, with primary performance evaluated by the area under the receiver operating characteristic curve (AUROC) and macro F1 score. In the primary validation set, the AACM-PP-Model achieved an AUROC of 0.897 (95% confidence interval [CI], 0.819-0.975) and macro F1 of 0.823. It outperformed the best parameter-only model (PP-CatBoost, AUROC of 0.885 [95% CI, 0.813-0.957], macro F1 of 0.821) and best image-only model (model based on suction-initiated, centering-checked frames and anterior axial curvature map [SIF-CCF-AACM-Model], AUROC of 0.837 [95% CI, 0.745-0.928], macro F1 of 0.612). Superiority of AACM-PP-Model over PP-CatBoost and SIF-CCF-AACM-Model was maintained in internal (AUROC 0.957 vs. 0.915 vs. 0.773) and external (0.863 vs. 0.814 vs. 0.660) test sets. Intraoperative frame models performed poorly (AUROC < 0.7 on all test sets). Multimodal machine learning using standard preoperative data can accurately predict small post-SMILE EOZ, demonstrating superior generalization to support preoperative decision-making. Objective preoperative risk stratification could aid in personalized surgical planning and help manage patient expectations regarding postoperative visual quality.

To evaluate a new nomogram technique, VISULYZE (Carl Zeiss Meditec AG), in small incision lenticule extraction (SMILE) surgery for treatment of myopia and myopic astigmatism. This was a prospective, nonrandomized, controlled study. VISULYZE is a specialized software platform for refractive surgeons that integrates patient data analysis with personalized nomogram generation. A total of 108 ideal eye examples (spherical equivalent [SE] within ±0.50 diopters [D] at 3 months postoperatively) were used for creation of the nomogram by VISULYZE. Another 100 eyes from 50 patients were enrolled in the SMILE 3.0 group (traditional nomogram), and 107 eyes from 55 patients in the SMILE 4.0 group (nomogram set by VISULYZE). All patients were followed up for 3 months, with monitoring of uncorrected distance visual acuity, corrected distance visual acuity, spherical equivalent, higher order aberrations, and the preoperative and postoperative complications. A nomogram was derived from a quadratic regression formula generated by VISULYZE to adjust the SE target. The safety of refractive outcome did not differ significantly in the two groups at the 3-month follow-up visit (P > .05). The efficacy index in the SMILE 4.0 group (1.11 ± 0.11) was significantly higher than in the SMILE 3.0 group (1.06 ± 0.14) (P < .05). In the SMILE 4.0 group, the predictability of error was 97% within ±0.50 D and 100% within ±1.00 D, compared with 81% and 99%, respectively, in the SMILE 3.0 group. The error of SE correction was -0.12 ± 0.30 and -0.36 ± 0.27 D for the SMILE 4.0 and SMILE 3.0 groups, respectively. There was no significant difference between the two groups in the root mean square values of total higher order aberrations, coma, trefoil, and spherical aberration at both 1 and 3 months postoperatively (P > .05). The nomogram generated by VISULYZE demonstrated comparable safety outcomes to a traditional nomogram while achieving significantly superior efficacy. This advanced nomogram technology also improves refractive prediction accuracy for SMILE procedures.

The Long-term observation of the quick contrast sensitivity and its influencing factors after SMILE.

Safety Thresholds for Removing and Preserving Corneal Tissue in Small-Incision Lenticule Extraction: A PRISMA-Compliant Study

The United States (U.S.) Military has been performing laser refractive surgery to enhance combat readiness, operational capability, and the quality of life for service members since fiscal year 2000. The latest laser refractive surgery adopted by the U.S. Military is small-incision lenticule extraction (SMILE) (Carl Zeiss Meditec AG, Jena, Germany), a type of keratorefractive lenticule extraction (KLEx). However, a limited number of studies have been conducted to determine whether varying levels of altitude have any effect on vision following the procedure. The purpose of this study was to evaluate the effect of decreased barometric pressure and atmospheric oxygen tension (simulated increased altitude up to 22,500 ft) on refractive stability in patients who have undergone bilateral SMILE. Study subjects included active duty military personnel who had undergone bilateral SMILE using the VisuMax femtosecond laser (Carl Zeiss Meditec AG) for the correction of myopia. After being cleared to participate in the study by a military flight medicine physician, each participant underwent altitude chamber training. Uncorrected visual acuity (UCVA), 5% low contrast (LC) UCVA, refractive error, corneal thickness, and anterior chamber volume and depth were each measured at ground level, 10,000 ft, 15,000 ft, 18,000 ft, and 22,500 ft simulated altitude in a hypobaric chamber. Mixed-effects linear regression models were used to evaluate the statistical significance of changes in individual outcome measures across different altitudes. Data from 34 eyes (17 participants) was collected during the study. A statistically significant increase was found in UCVA (-0.04 ± 0.01 LogMAR; P < .001) and LC UCVA (-0.05 ± 0.01 LogMAR; P < .001) as simulated altitude increased from ground level to 22,500 ft. A myopic shift (-0.14 ± 0.05 D; P = .050) was observed at 22,500 ft, as well as decreases in corneal thickness at central (-3.94 ± 0.83 µm; P < .001) and thinnest point (-3.65 ± 0.90 µm; P < .001). There were no statistically significant changes in mean keratometry, anterior chamber volume, or anterior chamber depth. The current study suggests that while high altitude may influence certain aspects of visual performance and corneal properties, overall visual acuity and anterior segment parameters remain stable in military personnel who underwent SMILE.

To investigate the association between functional outcomes and postoperative patient satisfaction 5y after small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). This is a cross-sectional study. The patients underwent basic ophthalmic examinations, axial length measurement, wide-field fundus photography, and accommodation function testing. Behavioral habits data were collected using a self-administered questionnaire, and visual symptoms were assessed with the Quality of Vision (QoV) questionnaire. Postoperative satisfaction was also recorded. Totally 410 subjects [820 eyes, 160 males (39.02%) and 250 females (60.98%)] who had undergone SMILE or FS-LASIK 5y ago were enrolled. The mean (standard deviation, SD) age of all patients was 29.83y (6.69). The mean (SD) preoperative manifest SE was -5.80 (2.04) diopters (D; range: -0.88 to -13.75). Patient satisfaction at 5y after undergoing SMILE or FS-LASIK was 91.70%. Patients were categorized into two groups: dissatisfied group and satisfied group. Significant differences were observed between the two groups in terms of age (P=0.012), sex (P=0.021), preoperative degree of myopia (P=0.049), postoperative visual symptoms (frequency, P=0.043; severity, P<0.001; bothersome, P=0.018), difficulty driving at night (P=0.001), and accommodative amplitude (AMP, P=0.020). Multivariate analysis confirmed that female sex (P=0.024), severity of visual symptoms (P=0.009), and difficulty driving at night (P=0.006) were significantly associated with lower satisfaction. The dissatisfied group showed higher rates of starbursts, double or multiple images, and high myopia, but lower age. The frequency, severity, and bothersome of distortion exhibited decreased with increasing age. Patient satisfaction 5y after SMILE and FS-LASIK is high and stable. Difficulty driving at night, sex, and severity of visual symptoms are important factors influencing patient satisfaction. Special attention should be paid to younger highly myopic female patients, particularly those with starbursts and double or multiple images. It is crucial to monitor postoperative visual outcomes and provide patients with comprehensive preoperative counseling to enhance long-term satisfaction.

This study aimed to construct a personalized, machine learning–driven nomogram capable of predicting refractive outcomes following small incision lenticule extraction (SMILE). A total of 1253 eyes from 632 patients who underwent SMILE to correct myopia or myopic astigmatism were retrospectively reviewed. Comprehensive preoperative and postoperative parameters were collected. Feature selection was performed using both clinical expertise and statistical approaches. Four machine-learning models – linear regression, decision tree, random forest, and neural network – were trained to estimate postoperative manifest refraction spherical equivalent (MRSE). The nomogram was established based on the best-performing model and subsequently evaluated using an external independent cohort. Among the tested algorithms, the random forest model demonstrated the highest predictive performance, achieving a mean absolute error (MAE) of 0.18 D, root mean square error (RMSE) of 0.24 D, and an R2 of 0.92 in the validation dataset. The final individualized nomogram incorporated 11 key predictors and maintained strong predictive ability when applied to the external validation set. The overall postoperative MRSE averaged −0.08 ± 0.32 D, with 92.3% and 99.4% of treated eyes falling within ±0.50 D and ±1.00 D of intended correction, respectively. The machine learning–derived personalized nomogram provides a highly accurate and transferable tool for forecasting SMILE refractive outcomes. Its implementation may contribute to improved precision and predictability in clinical refractive surgery planning.

To systematically evaluate and compare the performance of four leading large language models (LLMs) in generating medical literature reviews across topics of varying research maturity, thereby providing insights for their effective and responsible application in academic writing. In this comparative study, using standardized prompts, we instructed four leading LLMs (GPT-4, Gemini 2.5 Pro, Grok-3, and DeepSeek R1) to generate literature reviews on nine topics related to small incision lenticule extraction (SMILE) surgery. These topics were categorized into three groups by research maturity: well-researched, controversial, and open. Seven ophthalmology experts evaluated the generated content across four dimensions: quality, accuracy, bias, and relevance, while all references were verified for authenticity. Performance differences among models were evaluated using group comparison tests followed by post-hoc analysis. Significant performance variations were identified across all four models and dimensions (p < 0.001). Specifically, Gemini ranked highest in content quality, accuracy, and bias control. In contrast, DeepSeek, despite its high-quality score, received the lowest relevance score. Grok-3 demonstrated the highest reference authenticity (p < 0.001), whereas GPT-4's was the lowest (p < 0.001). All models showed diminished performance on open topics and exhibited severe reference fabrication ("hallucinations"). Rather than excelling universally, LLMs exhibit distinct and task-specific strengths that mandate a task-driven, hybrid strategy in tool selection. Reference fabrication was found to be a pervasive issue across all models, regardless of the task topic, elevating human verification from a best practice to an essential safeguard for academic integrity.

ObjectiveThis study aims to compare different intraocular pressure (IOP) correction formulas in post-refractive surgery patients who underwent Femtosecond Laser-Assisted In Situ Keratomileusis (FS-LASIK), Small Incision Lenticule Extraction (SMILE), and Trans-epithelial Photorefractive Keratectomy (tPRK), and to identify the most accurate formula for correcting IOP values measured by Goldmann applanation tonometer (GAT).MethodsThis prospective study included 160 patients (160 eyes) who underwent FS-LASIK (58 eyes), SMILE (52 eyes), or tPRK (50 eyes) at the Eye Hospital, Wenzhou Medical University. IOP was measured using GAT and Dynamic Contour Tonometry (DCT) preoperatively and 3 months postoperatively. Optical zone diameter, ablation depth (AD), residual stromal thickness, refractive error correction, central corneal thickness (CCT), and mean corneal curvature (Km) were collected. Fourteen published GAT correction formulas (F1–F14) were applied to postoperative GAT values and compared with preoperative measurements. Differences between pre- and postoperative DCT readings served as a reference.ResultsIn FS-LASIK and SMILE, formulas F3, F4, and F11 showed superior correction performance. In FS-LASIK, the mean differences, concordance correlation coefficients (CCC), and proportions of differences within ±2 mmHg were closer to or better than the DCT reference (0.58, 0.572, 55.17%), with F3 (0.25, 0.372, 72.41%), F4 (0.20, 0.373, 63.79%), and F11 (0.04, 0.324, 67.24%) showing high agreement. Similarly, in SMILE, F3 (0.25, 0.379, 57.69%), F4 (0.22, 0.375, 61.54%), and F11 (0.01, 0.399, 63.46%) outperformed or approximated DCT (0.86, 0.447, 44.23%). In tPRK, F1 (0.18, 0.653, 64.00%) and F2 (0.25, 0.316, 62.00%) provided better correction than DCT (0.19, 0.493, 56.00%).ConclusionFormulas F3, F4, and F11 are applicable for GAT IOP correction in both FS-LASIK and SMILE eyes. F1 and F2 are more suitable for tPRK; the preoperative IOP parameters included in F1 may lead to assessment bias, making F2 the recommended choice when preoperative IOP is unavailable.

We report an innovative use of the CIRCLE software (Carl Zeiss, Meditec) to manage a case of suction loss during small-incision lenticule extraction (SMILE). We describe a case of unstable suction during the corneal side-cut incision, wherein an immediate re-hold was obtained on the cornea, and the femtosecond delivery was completed. However, the side-cut incision was formed in the paracentral anterior cornea. The CIRCLE software (Pattern D) was used to fashion a new corneal side cut and gain subsequent access to the lenticule. The patient achieved an uncorrected distance visual acuity of 20/20 on postoperative day one. We present a rare case where the machine was able to re-establish suction after an excessive eye movement, while the laser delivery proceeded to continue uninterrupted. CIRCLE software provided a unique and novel application for gaining access to the SMILE lenticule in the case of failure of corneal side-cut formation in the intended location.

To evaluate the biomechanical properties of the cornea after refractive surgery using an inflation test combined with optical coherence tomography (OCT). Nine human donor corneas were divided into two groups: healthy (control) and treated (divided into three subgroups: photorefractive keratectomy [PRK], laser in situ keratomileusis [LASIK], and small incision lenticule extraction). Refractive treatments were applied to simulate -4.00 diopters of myopia correction. The corneas were mounted on an artificial anterior chamber, and an inflation test was performed using a custom set-up. Intraocular pressure was increased from 15 to 120 mm Hg in steps of 15 mm Hg, and corneal deformation was monitored via OCT imaging. The apex displacement versus IOP relationship was analyzed to calculate corneal stiffness, expressed as Young's modulus. Corneal thickness and curvature were also measured. Statistical comparisons were performed between healthy and treated corneas. All treated corneas exhibited significant reductions in thickness and Young's modulus compared to the healthy group. The mean corneal thickness was 552.0 ± 5.9 µm in the healthy group and 486.9 ± 14.0 µm in the treated group (P < .05). Young's modulus was significantly lower in treated corneas (14.2 ± 4.9 MPa) compared to healthy corneas (22.9 ± 0.5 MPa, P = .02). Among surgical techniques, LASIK resulted in the greatest reduction in corneal stiffness, whereas PRK showed the least impact. Inflation testing combined with OCT imaging allows for precise assessment of biomechanical alterations following refractive surgery. These findings highlight the importance of considering biomechanical consequences when selecting refractive procedures.