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Introduction: This study aimed to discover and document the potential of visual and ocular sequelae of computer vision syndrome (CVS) among medical students. Methods: This cross-sectional case-control study was conducted on medical students (n=4030) of five universities in Egypt. All students completed a specially designed and validated CVS questionnaire survey (CVS-F3). Students with ≥5 CVS symptoms constituted a risk group (n=352), while students with 1-4 CVS symptoms constituted a low-symptoms group (n=3067). Students from the control and risk groups were examined using objective methods, such as visual acuity, subjective refraction, dry eye disease tests, and anterior segment and fundus examinations. Students who complained of visual blur underwent multifocal electroretinography mfERG examinations (mfERG group). Results: The CVS-F3 indicated that 84.8% of students had complaints that might be related to CVS, however, our ophthalmic examination group revealed only a 56% CVS prevalence rate. The most common single screen type used by 70.4% of students was the smartphone, and the most common complaint was headache (50.2%). Multivariate logistic regression analysis revealed that CVS was significantly associated with increased screen-hours, including >2 screen-hours daily (odds ratio [OR], 2.48; P2 screen-hours at night (OR, 1.79; P=0.003), and ≥3 screen-years (OR, 1.69; P=0.006). In the mfERG group, 37% demonstrated reduced amplitudes of mfERG rings and quadrants, indicating reduced foveal responses. Conclusion: CVS-questionnaires overestimate the true CVS prevalence and sequelae, which could be accurately detected by objective ophthalmic examination. Smartphones primarily caused CVS among students, with CVS severity increasing in correlation with shorter eye-to-screen distance and frequent use. Contact lens wearing doubled the risk of CVS development and augmented its severity. CVS might affect macular integrity with screen-induced foveal dysfunction. Clinical Trials Registration: PACTR201811618954630.

Purpose To compare the safety and efficacy of standard 30 min epithelium‐off cross‐linking (CXL) versus photorefractive keratectomy (PRK) combined with accelerated epithelium‐off cross‐linking (AXL) for the treatment of progressive keratoconus (CXL‐Plus). Methods This study was a prospective multicentre comparative clinical study. A total of 125 eyes of 75 patients with grade 1 keratoconus and documented progression were divided into two groups. Group A included 58 eyes treated with standard CXL. Group B included 67 eyes treated with combined PRK and AXL. The recorded data included UDVA, CDVA, subjective and objective refraction, keratometry and pachymetry using corneal topographies preoperatively and postoperatively at 3, 6, 12 and 24 months of follow‐up. Results In group A, at 24 months of UDVA and CDVA were improved from 1.12 ± 0.38 and 0.58 ± 0.42 to 0.66 ± 0.20 and 0.20 ± 0.12 (LogMAR±SD). The spherical equivalent was reduced from 4.03 ± 1.18 to 1.78 ± 1.04 D. The cylinder reduction was 0.32 ± 0.19 D. In group B, at 24 months of UDVA and CDVA were improved from 1.26 ± 0.52 and 0.68 ± 0.36 to 0.58 ± 0.28 and 0.20 ± 0.16 (LogMAR ± SD). The spherical equivalent was reduced from 4.23 ± 0.95 to 1.92 ± 0.74 D. The cylinder reduction was ±1.76 D. Conclusion Surprisingly, standard CXL showed close results to CXL‐Plus at the 24th follow‐up month. Standard CXL acted as a stabilizing procedure associated with a late myopic component reduction. CXL‐Plus acted as a refractive and stabilizing procedure with an early effect on both the myopic and the astigmatic component but no later improvements. Standard CXL seems to be more powerful than AXL in its long‐term effect. Therefore, in the future, we want to test the combination of PRK with standard CXL.

Supplemental Digital Content is Available in the Text., Purpose: To evaluate the effectiveness and safety of combined epithelium-off cross-linking (CXL) with photorefractive keratectomy (CXL Plus) for correction of the myopic and astigmatic components of keratoconus. Methods: Seventy-nine eyes of 46 patients who underwent CXL Plus were enrolled in this retrospective, multicenter, noncomparative clinical study. Uncorrected distance visual acuity, corrected distance visual acuity, refraction, keratometry, and pachymetry measurements were recorded preoperatively and at 3, 6, 12, and 18 months during follow-up. Results: The mean (±SD) preoperative uncorrected distance visual acuity and corrected distance visual acuity were 1.00 ± 0.22 logarithm of the minimum angle of resolution (logMAR) and 0.62 ± 0.38 logMAR, respectively, and improved to 0.71 ± 0.36 logMAR and 0.32 ± 0.18 logMAR postoperatively. The mean k value, mean corneal thickness at the thinnest location, and mean myopic and astigmatic components decreased from 46.58 ± 0.97 D, 473 ± 29 μm, 3.65 ± 1.72 D, and 1.83 ± 0.69 D preoperatively to 43.79 ± 1.17 D, 431 ± 38 μm, 1.02 ± 0.78 D, and 1.15 ± 0.26 D, respectively, during follow-up. Eleven eyes had delayed epithelial healing, 2 had stromal opacities, 1 had primary herpes simplex keratitis, and 5 showed progression of keratoconus. Conclusions: CXL Plus improved the refractive status of keratoconus during 18 months of follow-up, despite its potential early postoperative complications of delayed epithelial healing and corneal haze. CXL Plus reduced the myopic component more than the astigmatic component of keratoconus. However, the safety and stability of the procedure were offset by longer-term postoperative complications and a high rate of postoperative progression of keratoconus.

Purpose: To evaluate the morphological changes of the ciliary body after diode laser trans-scleral cyclo-photocoagulation using ultrasound bio-microscopy in refractory glaucoma. Settings: This prospective, interventional, non-comparative, non-randomized, longitudinal study was performed on 40 eyes with refractory glaucoma, during the period between February 2016 and March 2018. Methods: All patients were treated with single session diode laser trans-scleral cyclo-photocoagulation. The intraocular pressure was obtained over a period of 3 months after the operation and morphological changes of the ciliary body were observed using ultrasound bio-microscopy. Results: Trans-scleral cyclo-photocoagulation has achieved a reasonable success in reducing intraocular pressure to less than 22 mm Hg without increasing the number of glaucoma medication. The overall success rate was 40%, as the intraocular pressure decreased from a baseline mean value of 54.70 ± 12.27 to 42.45 ± 9.85 mm Hg 1 week after operation, 33.50 ± 8.00 mm Hg after 1 month, and 25.60 ± 6.62 after 3 months of operation. Ultrasound bio-microscopy detected reduction in the length and width of ciliary processes in addition to the ciliary muscle thickness of the treated quadrants. Intraocular pressure was more correlated to the width of the ciliary processes. Conclusion: Trans-scleral cyclo-photocoagulation is a rapid and effective procedure in treatment of refractory glaucoma with intraocular pressure reduction. Ultrasound bio-microscopy is a promising twin tool for cyclo-destructive procedures to detect ciliary body changes and can be used as a guide for re-treatment procedures.

To analyze the visual and refractive outcomes of combined accelerated cross-linking with femtosecond laser intracorneal ring segment implantation for the treatment of pediatric keratoconus.This retrospective multicenter noncomparative clinical study included 63 eyes of 37 patients (age, 9-17 years) who underwent between August and September 2016 combined cross-linking with intracorneal ring segment implantation for keratoconus. Preoperative and postoperative (6, 12, and 18 months) uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), subjective refractions, keratometry (K), and pachymetry measurements were compared.The postoperative spherical equivalent refraction was within ±1 D, ±2 D, and ±3 D in 19 (30.2%), 27 (42.9%), and 37 (58.8%) eyes, respectively. Only 27 eyes achieved the attempted preoperative spherical equivalent refraction. The mean spherical equivalent refraction significantly improved from -6.01 ± 2.97 to -3.13 ± 2.78 D postoperatively (P 0.0001). The mean K average reading significantly decreased from 48.75 ± 4.25 to 46.65 ± 3.89 D postoperatively (P 0.0001). The mean postoperative myopic, astigmatic, and spherical equivalent corrections were -2.17 ± 2.19, -1.52 ± 2.03, and -2.93 ± 2.35 D, respectively. The mean UDVA and CDVA showed significant improvements (0.89 ± 0.33 to 0.40 ± 0.28, P 0.0001; 0.35 ± 0.31 to 0.25 ± 0.24, P = 0.004; respectively) at 18 months postoperatively. Keratoconus progression, segment migration, and segment extrusion were seen in four (6.4%), one (1.6%), and three (4.7%) eyes, respectively, probably contributing to the lower mean postoperative CDVA.Cross-linking plus is only partially effective for pediatric keratoconus. Despite some improvements in vision and keratometry measures, it resulted in complications such as keratoconus progression, segment extrusion, and segment migration that affected the vision in some patients. These findings suggest an assessment of standard epithelium-off collagen cross-linking as a sole procedure to treat pediatric keratoconus in future studies.

Purpose. To analyze the results of three-year outcomes of combined epithelium-on cross-linking with femtosecond laser ICRS (cross-linking PLUS) for keratoconus management. Design. A retrospective multicenter clinical study. Methods. 43 eyes of 38 patients were subjected to preoperative and postoperative UCVA, BCVA, refraction, Pentacam pachymetry, and keratometry examinations at 3-, 6-, 12-, 24-, and 36-month follow-up period. Results. The preoperative and postoperative mean UCVA was 1.30 ± 0.48 (logMAR ± SD) and 0.82 ± 0.22 respectively. The preoperative and postoperative mean BCVA was 0.90 ± 0.40 and 0.60 ± 0.30, respectively. The preoperative and postoperative mean K average was 50.63 ± 0.87 (D ± SD) and 45.56 ± 0.98, respectively. The preoperative and postoperative mean pachymetry was 471 ± 92.36 (μm ± SD) and 423 ± 39.58, respectively. The preoperative and postoperative mean astigmatism was 7.55 ± 1.75 and 3.39 ± 1.26, respectively. One eye showed ICRS edge exposure while 6 eyes showed progression of keratoconus. Conclusion. CXL PLUS was proved to be a successful procedure to halt progression (mainly by CXL) and to correct the refractive status of the keratoconic eye (mainly by ICRS). CXL PLUS performed a synergistic action correcting and maintaining the correction of both myopic and astigmatic components of keratoconus.