Moseley M J, Fielder A R, Irwin M, Jones H S, Auld R J
Academic Unit of Ophthalmology, Imperial College of Science, Technology and Medicine, London.
Br J Ophthalmol. 1997 Nov;81(11):956-61. doi: 10.1136/bjo.81.11.956.
AIMS/BACKGROUND: To examine the relative contributions of non-specific (for example, spectacle correction) and specific (that is, occlusion therapy) treatment effects on children with ametropic amblyopia. To assess the importance and practicality of objectively confirming the prescribed occlusion dose.
Subjects were entered into a two phase trial. In the first ('pretreatment') subjects were provided with spectacle correction and underwent repeat visual acuity (VA) and contrast sensitivity (CS) testing until acuity in their amblyopic eye had stabilised. Subjects then progressed to the second phase ('treatment') in which they underwent direct, unilateral occlusion for 1 hour per day for 4 weeks. Patching was objectively monitored using an occlusion dose monitor.
Eight subjects completed the trial, all but one of whom achieved > 80% concordance with the occlusion regimen. Within the pretreatment phase, mean amblyopic eye VA improved by 0.19 log units (p = 0.008) while mean CS gained 0.09 log units (p = 0.01). An identical improvement in mean VA was recorded in the fellow eyes (p = 0.03) while mean CS gained 0.11 log units (p = 0.02). Within the treatment phase, mean VA further improved (0.12 log units, p = 0.009) although this gain had halved by the end of treatment and was no longer statistically significant (p = 0.09).
Visual performance improved significantly during pretreatment whereas further gains seen during occlusion were not sustained. Evaluation of occlusion regimens must take into consideration the potentially confounding influence of 'pretreatment effects' and the necessity to confirm objectively the occlusion dose a child receives.
目的/背景：研究非特异性治疗（如眼镜矫正）和特异性治疗（即遮盖疗法）对屈光不正性弱视儿童的相对作用。评估客观确认规定遮盖剂量的重要性和实用性。
受试者进入两阶段试验。在第一阶段（“预处理”），为受试者提供眼镜矫正，并进行重复视力（VA）和对比敏感度（CS）测试，直至弱视眼视力稳定。然后受试者进入第二阶段（“治疗”），在此阶段他们每天进行1小时的直接单侧遮盖，持续4周。使用遮盖剂量监测仪对遮盖情况进行客观监测。
8名受试者完成试验，除1名外，其他所有受试者的遮盖方案依从性均>80%。在预处理阶段，弱视眼平均视力提高0.19对数单位（p = 0.008），而平均对比敏感度提高0.09对数单位（p = 0.01）。对侧眼平均视力有相同程度的提高（p = 0.03），而平均对比敏感度提高0.11对数单位（p = 0.02）。在治疗阶段，平均视力进一步提高（0.12对数单位，p = 0.009），尽管这一提高在治疗结束时减半且不再具有统计学意义（p = 0.09）。
预处理期间视力显著改善，而遮盖治疗期间进一步提高的效果未持续。评估遮盖方案时必须考虑“预处理效应”的潜在混杂影响以及客观确认儿童接受的遮盖剂量的必要性。
