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Purpose: To present the outcomes and detail the surgical procedure employed in the initial 102 eyes treated with keratorefractive lenticule extraction (KLEx) using the FEMTO LDV Z8 platform (Ziemer Ophthalmic Systems). Methods: This was a retrospective analysis of 102 eyes of 53 patients treated with KLEx at the American University of Beirut Medical Center. Visual, refractive, topographic, and aberrometric parameters were evaluated 1 week and 1, 3, 6, and 12 months postoperatively. Results: Mean preoperative spherical equivalent refraction (SEQ) was −4.11 ± 1.82 diopters (D) (range: −10.00 to −1.625 D) and mean preoperative cylinder was −0.75 ± 0.65 D (range: −3.00 to 0.00 D). Postoperatively, the mean SEQ was 0.06 ± 0.54 D (range: −2.88 to +1.00 D) at 1 week and −0.04 ± 0.26 D at 12 months and was within ±0.50 D in 95.6% and ±1.00 D in 100% of eyes. A total of 96.7% of eyes had an uncorrected distance visual acuity (UDVA) of 20/20 at 12 months postoperatively. Fifty percent gained one or more lines of corrected distance visual acuity (CDVA), 5 eyes (5.4%) lost one line, and none lost two or more lines. No suction losses were encountered and all extracted lenticules were intact without tears. Conclusions: The application of KLEx using the FEMTO LDV Z8 platform yields safe and effective outcomes, aligning comparably with established modes of lenticule extraction and femtosecond laser–assisted laser in situ keratomileusis procedures previously employed and accepted within the field of refractive surgery. [J Refract Surg. 2024;40(11):e898–e905.] [ABSTRACT FROM AUTHOR]

Purpose: To compare and assess the visual, refractive, and tomographic results of patients with corneal ectasia treated with either corneal allogenic intrastromal ring segments (CAIRS) or synthetic intrastromal corneal ring segments (ICRS) without concomitant corneal cross-linking. Methods: In this retrospective cohort study, 34 eyes with CAIRS were matched to 34 eyes with ICRS using the propensity score matching technique. Each group was matched on a oneto-one basis using multiple parameters such as central corneal thickness, vertical and horizontal coma, maximum anterior keratometry, steepest keratometry, and age. Visual, refractive, topographic, and aberrometric data were measured at baseline, 1 week, 1 month, 3 months, and 1 year postoperatively. Results: Initial preoperative parameters were similar between the two groups. Both groups showed significant improvement at last follow-up time in corrected distance visual acuity (CDVA) (0.52 ± 0.23 to 0.16 ± 0.18 logarithm of the minimum angle of resolution [logMAR], P <.001; 0.44 ± 0.27 to 0.17 ± 0.21 logMAR, P <.001), topographic astigmatism (4.45 ± 2.75 to 3.14 ± 1.93 diopters [D], P =.001; 3.66 ± 2.22 to 2.36 ± 1.46 D, P =.007), maximum anterior keratometry (55.85 ± 7.53 to 50.69 ± 6.38 D, P <.001; 54.59 ± 6.95 to 50.71 ± 4.51 D, P =.003), and vertical coma (1.49 ± 1.02 to 0.38 ± 0.65 D, P <.001; 1.22 ± 0.75 to 0.52 ± 0.57 D, P <.001) for CAIRS and ICRS, respectively. The improvements observed in both groups at the last follow-up visit were comparable; however, the CAIRS group demonstrated a higher percentage of eyes gaining two or more Snellen lines of CDVA (60% vs 31.58%, P =.04), and a greater magnitude of reduction in vertical coma compared to the ICRS group, although this difference did not reach statistical significance. No major complications were observed with both groups, and one eye lost one CDVA line in the ICRS group. The mean thickness of the CAIRS segments at the last follow-up visit was 401.06 ± 100.12 µm, compared to 435.29 ± 26.19 µm for ICRS. Both CAIRS and ICRS demonstrated significant compression of stromal thickness above the segment (36.19% and 32.00%, respectively). Conclusions: When adequately matched for preoperative disease type and severity, eyes with CAIRS had a similar and notable clinical improvement compared to ICRS, with possibly better improvement in vertical coma and CDVA. [J Refract Surg. 2024;40(11):e863–e876.] [ABSTRACT FROM AUTHOR]

Objectives: This pilot ex vivo study and first clinical experience in Italy evaluate the impact of using pre-implantation crosslinking on all-femtosecond laser-cut corneal allogenic intracorneal ring segments (AFXL CAIRSs). Methods: Six human donor eye-bank corneas were used for this preclinical ex vivo human study. Three donor (D) corneas were used for AFXL CAIRSs. First, they were prepared with an IntraLase™ femtosecond laser (Johnson & Johnson, New Brunswick, NJ, USA). The allogenic tissue rings were crosslinked before implantation with Riboflavin–UV-A accelerated crosslinking protocol (ACXL) with a 0.1% HPMC Riboflavin isotonic solution (Vibex Rapid, Glaukos-Avedro, Burlington, MA, USA) and a new KXL UV-A emitter (Glaukos-Avedro, USA). Three corneas were used as recipients (Rs) of the AFXL CAIRSs. After completing the ex vivo phase, IRB approval and signing a specific informed consent, the first two Italian patients were treated. A single ACXL CAIRS was implanted in a 51-year-old male with 53.53 D K steep, 363 μm minimum corneal thickness (MCT) and a double ACXL CAIRS was implanted in a 46-year-old male patient with 58.30 D K steep, 443 μm MCT. The longest follow-up was at three months. Results: Crosslinking of the segments enhanced tissue stiffness and grip, facilitating manipulation and CAIRS insertion into the recipient tunnels, and the yellowish color of the crosslinked segments improved visibility. The segment's thickness and volume remained unaltered during the follow-up. Both patients improved UDVA and BSCVA. K steep and High-Order Aberrations (HOAs) were reduced and MCT increased. Conclusions: Pre-implantation ACXL facilitated CAIRS insertion preserving dimensions and volume during the follow-up, rendering this important step a promising candidate in method standardization. Functional data and MCT improved significantly without adverse events. [ABSTRACT FROM AUTHOR]

Aims: To develop a generative adversarial network (GAN) capable of generating realistic high-resolution anterior segment optical coherence tomography (AS-OCT) images. Methods: This study included 142 628 AS-OCT B-scans from the American University of Beirut Medical Center. The Style and WAvelet based GAN architecture was trained to generate realistic AS-OCT images and was evaluated through the Fréchet Inception Distance (FID) Score and a blinded assessment by three refractive surgeons who were asked to distinguish between real and generated images. To assess the suitability of the generated images for machine learning tasks, a convolutional neural network (CNN) was trained using a dataset of real and generated images over a classification task. The generated AS-OCT images were then upsampled using an enhanced super-resolution GAN (ESRGAN) to achieve high resolution. Results: The generated images exhibited visual and quantitative similarity to real AS-OCT images. Quantitative similarity assessed using FID scored an average of 6.32. Surgeons scored 51.7% in identifying real versus generated images which was not significantly better than chance (p value >0.3). The CNN accuracy improved from 78% to 100% when synthetic images were added to the dataset. The ESRGAN upsampled images were objectively more realistic and accurate compared with traditional upsampling techniques by scoring a lower Learned Perceptual Image Patch Similarity of 0.0905 compared with 0.4244 of bicubic interpolation. Conclusions: This study successfully developed and leveraged GANs capable of generating high-definition synthetic AS-OCT images that are realistic and suitable for machine learning and image analysis tasks. [ABSTRACT FROM AUTHOR]

Purpose: To compare haze and refractive outcomes in patients undergoing combined accelerated corneal cross-linking (A-CXL) and selective wavefront-guided transepithelial photorefractive keratectomy (WG-transPRK) without mitomycin C (MMC) versus those undergoing A-CXL. Methods: This prospective study analyzed 95 eyes (86 patients) with progressive keratoconus from October 2018 to October 2022. The first group underwent CXL combined with corneal or ocular WG-transPRK (CXL+PRK, n = 52), targeting higher order aberrations (HOAs). The second underwent CXL only (n = 43), both following the same accelerated CXL protocol without MMC on the SCHWIND Amaris laser platform (SCHWIND eye-tech-solutions). Baseline and postoperative evaluations (1, 3, 6, and 12 months) included uncorrected (UDVA) and corrected (CDVA) distance visual acuity, manifest refraction, tomography, corneal HOAs, and optical coherence tomography (OCT) scans. A patented machine learning algorithm objectively detected and quantified stromal haze on OCT scans in grayscale units. Results: In both groups, anterior corneal haze reflectivity and subepithelial haze peaked at 3 months postoperatively, then progressively decreased at 6 and 12 months. Haze did not differ between groups at any time point. By 12 months, CDVA increased by 2.5 lines in the CXL+PRK group (P <.001) and by 0.7 lines in the CXL group (P =.10), and maximum keratometry decreased from 51.70 ± 5.10 to 47.90 ± 7.90 diopters (D) (CXL+PRK group) (P <.001) and from 51.20 ± 5.10 to 50.30 ± 4.60 D (CXL group) (P =.004). Corneal HOAs decreased in both groups but more in the CXL+PRK group. Conclusions: Combining CXL with WG-transPRK without MMC does not result in increased haze when compared to A-CXL alone. This combined approach achieves greater improvements in visual, topographic, and aberrometric parameters. [J Refract Surg. 2024;40(9):e583–e594.] [ABSTRACT FROM AUTHOR]

The leaves of Nicotiana glauca (N. glauca; Solanaceae) plant are a known, major human health concern. This study investigated the antioxidant activity and polyphenols composition of aerial parts of N. glauca collected from its wild habitat in Jordan, using Methanol-Conventional (MC) and deep eutectic solvents (DES) extraction methods in addition to nicotine content determination using UHPLC. Our results showed that the MC extract contains fewer total phenols and flavonoid content than the 90% DES extract, (0.1194 ± 0.009 and 0.311 ± 0.020 mg/mL equivalent to gallic acid) and (0.01084 ± 0.005 and 0.928 ± 0.09 mg/mL equivalent to rutin), respectively. Moreover, this study showed that the prepared MC extract contain 635.07 ppm nicotine, while the 90% DES extract contain 1194.91 ppm nicotine. Extracts prepared using the MC and the DES methods exhibited weak antioxidant activities; the highest was a 33% inhibition rate (equivalent to ascorbic acid), obtained by the 90% DES extract,. The performed UHPLC-MS/MS analysis in this study also revealed the presence of variations in the detected compounds between the two extraction methods. Furthermore, this study found that environmentally friendly DES extraction of N. glauca produced higher phenol and flavonoid content than the MC method; this highlights the superior efficiency and environmental benefits of sustainable chemistry methods for extracting valuable phytoconstituents. [ABSTRACT FROM AUTHOR]