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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; P<0.0001), >2 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 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.

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 (Log MAR ± 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 (Log MAR ± 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 .

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