Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.
Ophthalmic Physiol Opt. 2021 Mar;41(2):213-223. doi: 10.1111/opo.12775. Epub 2021 Jan 6.
The measurement of standard visual acuity (VA) is the most well-known part of any ophthalmic examination to indicate visual function. Despite this, it is insensitive in detecting early disease changes. Therefore, other visual function tests have been developed including low luminance VA (LLVA) and low luminance deficit (LLD). This scoping literature review aims to summarise the current published applications of LLVA and LLD assessments to evaluate their utility as clinical markers and research outcome measures in a variety of ophthalmic conditions.
Sixty-five peer-reviewed publications were included. LLVA was pioneered for use in geographic atrophy, a subtype of age-related macular degeneration, which remains the mainstay of its clinical application. However, other studies have reported additional useful applications in inherited retinal diseases including rare maculopathies and rod-cone dystrophies. Although there are some variations in testing methodology, use of the standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart with a 2.0 log unit neutral density filter is the most popular approach. The optimal testing luminance is still to be defined.
Overall, LLVA is an earlier clinical marker of change in central retinal function than standard VA. It has been shown to be a risk factor for disease progression and a better indicator of a patient's level of everyday visual function. It is inexpensive and simple to implement using readily available standard ophthalmic equipment.
标准视力（VA）的测量是眼科检查中最著名的部分，用于指示视觉功能。尽管如此，它对早期疾病变化的检测不敏感。因此，已经开发了其他视觉功能测试，包括低亮度 VA（LLVA）和低亮度缺损（LLD）。本范围文献综述旨在总结目前已发表的使用低亮度 VA 和低亮度缺损评估的应用，以评估它们作为各种眼科疾病的临床标志物和研究结果测量的效用。
共纳入 65 篇同行评议的出版物。低亮度 VA 最初用于年龄相关性黄斑变性的一种亚型——地图状萎缩，这仍然是其临床应用的主要方法。然而，其他研究还报告了在遗传性视网膜疾病中的其他有用应用，包括罕见的黄斑病变和杆锥细胞营养不良。尽管测试方法存在一些差异，但使用标准的早期糖尿病视网膜病变研究（ETDRS）图表和 2.0 对数单位的中性密度滤光片是最受欢迎的方法。最佳测试亮度仍有待确定。
总的来说，低亮度 VA 是中央视网膜功能变化的早期临床标志物，比标准 VA 更早。它已被证明是疾病进展的风险因素，也是患者日常视觉功能水平的更好指标。它使用现成的标准眼科设备，价格低廉，易于实施。
