Harkin Darragh Liam, Little Julie-Anne, McCullough Sara J
Centre for Optometry and Vision Science, School of Biomedical Sciences, Faculty of Life and Health Sciences, Ulster University, Coleraine, Northern Ireland.
PLoS One. 2025 Jun 30;20(6):e0309625. doi: 10.1371/journal.pone.0309625. eCollection 2025.
Visual stress is a reading disorder characterised by perceptual distortions, asthenopia and headache whilst reading, alongside increased sensitivity to repeated striped patterns ('pattern glare'), in the absence of underlying ocular pathology. Coloured filters including tinted spectacle lenses and coloured overlays/acetates have been reported to ameliorate visual stress symptoms. However, evidence on coloured spectacle lenses efficacy at managing symptoms of visual stress, particularly in adults, is lacking, with recent systematic reviews advocating the need for large-scale randomised control trials.
This is a double-masked randomised placebo-controlled superiority trial. University students identified with symptoms of visual stress, through use of a reading symptom questionnaire and mid-spatial frequency pattern glare test, will be recruited. Sample size for power of 90% at 5% significance, accounting for 10% dropout will be 65. Participants will be randomly assigned experimental and control coloured spectacle lenses to wear for six weeks followed by a two week washout period, prior to wear of the alternate lenses for a further six weeks with a two week washout period. Participants will compare both sets of spectacle lenses in a 'head-to-head' comparison after the secondary washout period, prior to choosing the preferred lenses for voluntary future wear. Long-term adherence to the preferred lenses will be assessed three months post-comparison. Researchers and participants will be masked to spectacle lenses worn throughout the duration of the trial. Reading performance will be assessed with both sets of lenses at various time points within the trial. A range of reading tests, reading symptoms and pattern glare evaluation will be used to monitor change in reading performance and visual stress symptoms during the trial.
The study will evaluate the hypothesis that coloured spectacle lenses increase reading speed and reduce severity and frequency of reading symptoms in adults with visual stress.
The trial is registered at ClinicalTrials.gov: NCT04318106.
视觉应激是一种阅读障碍，其特征为阅读时出现感知扭曲、眼疲劳和头痛，同时对重复的条纹图案（“图案眩光”）敏感度增加，且不存在潜在的眼部病变。据报道，包括有色眼镜片和彩色覆盖物/醋酸酯在内的滤色镜可改善视觉应激症状。然而，缺乏关于有色眼镜片缓解视觉应激症状有效性的证据，尤其是在成年人中，最近的系统评价主张需要进行大规模随机对照试验。
这是一项双盲随机安慰剂对照优势试验。将招募通过阅读症状问卷和中空间频率图案眩光测试确定有视觉应激症状的大学生。在5%显著性水平下，为达到90%的检验效能并考虑10%的失访率，样本量将为65。参与者将被随机分配佩戴实验性和对照性有色眼镜片六周，随后有两周的洗脱期，之后再佩戴另一组眼镜片六周并再有两周的洗脱期。在第二次洗脱期后，参与者将“面对面”比较两组眼镜片，然后选择更偏好的眼镜片以便日后自愿佩戴。将在比较后三个月评估对更偏好眼镜片的长期依从性。在试验期间，研究人员和参与者都将对所佩戴的眼镜片不知情。将在试验的不同时间点用两组眼镜片评估阅读表现。将使用一系列阅读测试、阅读症状和图案眩光评估来监测试验期间阅读表现和视觉应激症状的变化。
该研究将评估有色眼镜片能否提高有视觉应激的成年人的阅读速度，并减轻阅读症状的严重程度和频率这一假设。
该试验已在ClinicalTrials.gov注册：NCT04318106。
