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Autologous Fibrin Glue in Pterygium Surgery as an Alternative to Commercial Fibrin Glue.

PURPOSE: The aim of this study was to evaluate the efficacy and safety of autologous fibrin glue in pterygium surgery, comparing it with commercial fibrin glue in terms of postoperative complications, graft stability, and recurrence rate. METHODS: A prospective, randomized, double-blind study was conducted, involving 42 patients with primary pterygium who underwent autologous conjunctival-limbal transplantation. The graft was fixed using autologous fibrin glue (Group 1, G1) or commercial fibrin glue (Group 2, G2). All patients underwent surgery performed by the same surgeon and were reevaluated on postoperative days 7, 30, 90, and 180 by an independent observer, assessing clinical parameters in the preoperative, intraoperative, and postoperative periods. RESULTS: No cases of severe adverse events were reported. Complete graft dehiscence occurred in 1 patient from G1. The G2 group had more cases of subconjunctival hemorrhage ( P = 0.0355). Pyogenic granuloma was observed in 1 patient from G2 and 2 patients from G1. There was no significant difference in recurrence rates between the groups (15% in G1 vs. 5% in G2; P = 0.2918). In both groups, graft dimensions tended to decrease slightly in the early postoperative period, followed by stabilization. CONCLUSIONS: Autologous fibrin glue demonstrated efficacy and safety comparable to commercial fibrin glue, making it a viable alternative to conjunctival graft fixation in primary pterygium surgery.

Humans

Artificial Intelligence for Diagnosing Meibomian Gland Dysfunction: A Systematic Review and Meta-Analysis of Diagnostic Test Accuracy Studies.

PURPOSE: To identify, appraise, and synthesize the performance of artificial intelligence-based meibography reading as compared with human graders in diagnosing meibomian gland dysfunction. METHODS: We followed Cochrane methodology and reporting guidelines for diagnostic test accuracy reviews. To assess potential risk of bias and applicability, we used a modified Quality Assessment of Diagnostic Accuracy Studies-2 checklist. We applied bivariate logistic models to estimate summary sensitivity and specificity when appropriate and used the GRADE framework to rate the certainty of the evidence. RESULTS: We identified 14 eligible studies involving 5511 predominantly middle-aged participants (average age: 27-55 years) who were primarily female (≥54.5%). A total of 18,926 meibography images were obtained through noncontact infrared (11 studies) or in vivo confocal microscopy (three studies). Two studies reported external validation of deep learning models, 12 reported internally validated models, and one reported both. All but one study had high risk of bias in at least one domain; 12 studies raised high or intermediate concern about applicability. Based on three external evaluations, the summary sensitivity and specificity for diagnosing meibomian gland dysfunction from normal glands were 97.5% (95% confidence interval: 77.5%-99.8%) and 85.5% (95% confidence interval: 47.3%-97.5%). Sources of heterogeneity in internally validated models included study population, case mix, and others. The overall evidence was very low to low certainty because of imprecision, high risk of bias, and concerns about applicability. CONCLUSIONS: Artificial intelligence-based meibography grading appears less accurate than human graders. Future studies should adopt rigorous designs, including a more diverse participant pool (or image set), and external validation.

Humans

Evaluation of a cornea-specialized large language model for diagnostic and management accuracy in complex corneal cases.

PURPOSE: To evaluate whether a cornea-specialized large language model (LLM) enhanced with retrieval-augmented generation (RAG) improves clinicians' diagnostic and management accuracy in complex corneal cases compared to a general-purpose GPT-4o model and unaided clinician performance. METHODS: This prospective, randomized, masked evaluation study involved three cornea trainees who each independently reviewed 39 real-world corneal cases under three experimental conditions: unaided, GPT-4o-assisted, and assisted by a cornea-specialized GPT-4o model. The cornea-specialized model was constructed by embedding over 200 publicly available Wikipedia articles into GPT-4o's RAG framework. Participants provided open-ended diagnoses and selected the next-step management options (multiple choice). They were allowed up to three GPT-4o queries per case, and the AI-assisted arms were randomized to minimize bias. Accuracy for both tasks was compared against expert reference standards using McNemar's test. RESULTS: Diagnostic accuracy was 48.7%, 20.5%, and 38.5% unaided, improving to 69.2%, 46.2%, and 59.0% with general GPT-4o (p<0.04). The cornea-specialized GPT-4o further improved accuracy to 71.8%, 48.7%, and 74.4%, with improvements over unaided performance for all clinicians (p<0.01). For next-step decisions, unaided accuracy was 76.9%, 87.2%, and 59.0%. With the specialized model, Ophthalmologist 3 improved to 71.8% (p<0.05), Ophthalmologist 1 remained high at 82.1%, and Ophthalmologist 2 declined to 64.1% (p<0.05). CONCLUSIONS: A cornea-specialized LLM enhanced with RAG improved diagnostic accuracy in complex corneal cases, particularly among clinicians with lower baseline performance. Effects on management accuracy were inconsistent. Future studies should explore the use of open-ended management tasks and examine whether smaller, curated retrieval corpora yield better model performance.

Humans

Second-Generation ELZA-sub400 Protocol: Individualized High-Fluence Cross-Linking for Ultra-Thin Keratoconus Corneas.

PURPOSE: To evaluate the safety and efficacy of a second-generation individualized corneal cross-linking (CXL) protocol (ELZA-sub400) using high-fluence UV-A irradiation in ultrathin ectatic corneas. DESIGN: Retrospective, single-center, consecutive interventional case series. METHODS: Twenty-nine eyes of 24 patients with progressive keratoconus or post-LASIK ectasia and a post-soak intraoperative thinnest stromal thickness <400 &#xb5;m were included. After epithelial removal and riboflavin soaking, continuous UV-A irradiation (365 nm) at 3 or 9 mW/cm&#xb2; was delivered with total fluence titrated up to 10 J/cm&#xb2; based on intraoperative ultrasound pachymetry and a previously published nomogram targeting an uncross-linked stromal margin of approximately 70 &#xb5;m above the endothelium. Outcomes were assessed at baseline and up to 12 months using corrected distance visual acuity (CDVA) and corneal parameters measured using Scheimpflug tomography and anterior segment OCT (AS-OCT) with Placido-based topography. The main outcome measure was the proportion of eyes without progression at 12 months, defined as <1.0 D increase in maximum keratometry (Kmax). Secondary outcomes included changes in CDVA, refraction, Kmax, stromal thickness, demarcation line depth, densitometry, and safety parameters. RESULTS: At 12 months, 22/29 eyes (76%; 95% CI, 57.9%-87.8%) met the nonprogression criterion. Mean change in Kmax was -0.77 &#xb1; 5.10 D (95% CI, -2.71 to 1.17; P = .418). Mean demarcation line-to-anterior stroma distance was 205 &#xb1; 64 &#xb5;m (95% CI, 180.7-229.3), and demarcation line-to-endothelium distance was 64 &#xb5;m (IQR, 49-152). All demarcation lines remained within the stromal layer; 15/29 eyes (51.7%) had a demarcation line located &#x2264;70 &#xb5;m from the endothelium. Median CDVA changed from 0.10 to 0.32 logMAR (P = .142). Minimum stromal thickness showed a median change of -4.0 &#xb5;m (P = .309). No significant change was observed in densitometry, and no eye developed deep stromal haze or endothelial decompensation. CONCLUSIONS: Second-generation ELZA-sub400 CXL halted ectasia progression in 76% of ultrathin corneas at 12 months and was associated with an acceptable short-term safety profile, including stromal-confined demarcation line formation and no observed endothelial decompensation. The numerical decline in spectacle CDVA observed in this severely affected cohort did not reach statistical significance but is clinically important and warrants confirmation in larger prospective studies.

Humans

Xerophthalmia and ocular manifestations of vitamin A deficiency in children in high-income countries: A systematic review.

Xerophthalmia is a vision-threatening eye condition caused by vitamin A deficiency (VAD). Cases of xerophthalmia in high-income countries (HICs) are vulnerable to misdiagnosis, causing delays in treatment and adverse visual outcomes. We define the features, causes and complications of VAD and xerophthalmia in children of HICs. Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines (CRD42024492023). We performed a search for eligible articles on Scopus, Web of Science, Cochrane, PubMed and Medline. Cases reporting on children under 18 years of age residing in HICs with ocular features of VAD were eligible for inclusion. The search yielded 2474 results; 43 case reports and case series met the inclusion criteria consisting of a total of 61 cases (mean age 9.9&#x202f;&#xb1;&#x202f;4.2 years, range 3-17 years). Xerophthalmia was graded according to the most advanced finding for each case: 21.3% had night blindness only; 29.5% had conjunctival xerosis or Bitot spots; 29.5% had corneal xerosis, ulceration or scarring; 1.6% had xerophthalmia fundus only; and 18.0% had ocular manifestations associated with VAD that are not encompassed under the WHO classification. These features included swollen optic discs, optic neuropathy, or ocular dryness. Restrictive dietary practises were the most common mechanism of deficiency (75%), and autism was the most common underlying condition (49%). This shows that VAD remains a cause of severe visual impairment in HICs, especially when associated with delays in diagnosis and treatment. Further research is required to establish the prevalence of xerophthalmia in HICs.

Humans

Comparison of Ketamine and Pregabalin on Postoperative Opioid Usage and Pain Management in Spinal Fusion: Systematic Review and Network Meta-analysis.

BACKGROUND CONTEXT: Spinal fusion is associated with substantial early postoperative pain and opioid exposure. Both ketamine and pregabalin are widely incorporated into Enhanced Recovery After Surgery (ERAS) protocols as opioid-sparing adjuncts. However, their comparative efficacy and safety in this specific setting remain uncertain. Our objective was to compare ketamine and pregabalin indirectly for early postoperative opioid consumption, pain, and adverse events in adults undergoing spinal fusion. METHODS: Pubmed, Embase, and Cochrane Trials were searched from inception through October 2025. Eligible studies were randomized trials enrolling adults undergoing instrumented spinal fusion, randomized to perioperative ketamine, pregabalin, or control, and reported extractable 24-hour opioid consumption or pain outcomes. Continuous outcomes were pooled as mean differences in MME or VAS units, and adverse events were reported descriptively. A connected treatment network was analyzed using random-effects models. Risk of bias (RoB) was assessed with the Cochrane RoB 2 tool. RESULTS: Thirteen trials (n=879) were included: ketamine (n=210), pregabalin (n=271), and control (n=398). Six trials contributed opioid data (3 ketamine, 3 pregabalin). Using pregabalin 150 mg as reference, ketamine was associated with lower 0-24-hour opioid use (MD -56.99 mg MME; 95% CI -99.56 to -14.43). Control (MD +21.31; 95% CI -1.05 to +43.66) and pregabalin 300 mg (MD -13.22; 95% CI -40.41 to +13.96) did not significantly differ from pregabalin 150 mg. Seven trials contributed 24-hour VAS data, with control being associated with higher pain versus pregabalin 150 mg (MD +0.84; 95% CI +0.01 to +1.66), while ketamine and pregabalin 300 mg were not k significantly different. Adverse events were generally infrequent and similar to control. CONCLUSIONS: Both ketamine and pregabalin provide early opioid sparing with comparable 24-hour analgesia. Ketamine showed a larger opioid-sparing point estimate, but indirect comparisons are imprecise. Adequately powered head-to-head trials with standardized protocols and adverse event reporting are needed.

Humans

A validated sensitive LC-MS/MS method and its application in elucidating the unique ocular pharmacokinetic profile of 0.01% atropine underpinning its clinical utility for myopia.

A sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to quantify atropine in ten rabbit ocular tissues enabling systematic characterization of the ocular pharmacokinetic profile of 0.01% atropine sulfate eye drops after a single topical administration. The method demonstrated excellent linearity (coefficient of determination, R2&#xa0;&#x2265;&#xa0;0.9908) across all matrices, with lower limits of quantification (LLOQ) of 0.05&#xa0;ng/mL for most tissues and 0.10&#xa0;ng/mL for retina and lens; intra- and inter-day accuracy, precision, matrix effects, extraction recoveries, and stability all met the acceptance criteria. Following a single bilateral topical dose (50&#xa0;&#x3bc;L/eye) in New Zealand White rabbits, atropine distributed rapidly into all 12 ocular compartments (the sclera further divided into three anatomical regions) with marked heterogeneity-the highest exposures were found in conjunctiva and cornea, a distinct anterior-to-posterior concentration gradient was observed in the sclera, sustained retention was noted in the retina (mean residence time from zero to the last measurable time point, MRT0-t 3.30&#xa0;h), while aqueous and vitreous humor eliminated rapidly (elimination half-life, t&#x2081;/&#x2082;&#xa0;<&#xa0;0.7&#xa0;h), and all tissues except aqueous humor followed a two-compartment model. This validated method and the comprehensive pharmacokinetic data reveal that topically applied 0.01% atropine achieves sustained exposure in key myopia-regulating tissues (retina, choroid, posterior sclera) with low exposure in side-effect target tissues (iris, ciliary body, lens).

Animals