City, University of London, Optometry and Visual Sciences, London, United Kingdom.
Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom.
Sci Rep. 2018 Jan 26;8(1):1648. doi: 10.1038/s41598-018-20092-y.
Detection and evaluation of inflammatory activity in uveitis is essential to the management of the condition, and yet continues to be largely dependent on subjective clinical measures. Optical coherence tomography (OCT) measurement of vitreous activity is an alternative to clinical vitreous haze scoring and has passed a number of early validation studies. In this study we aimed to evaluate the impact of 'operator factors' on the variability of the technique as part of the validation process, and to help evaluate its suitability for 'real world' use. Vitreous haze index was calculated as a ratio between the reflectivity of the vitreous and of the outer retina in each scan. Different scanning conditions were tested and their effect on the measurement is reported. Our results show that the 'quantitative imaging' technique of OCT-measured vitreous activity had good reliability in normal subjects under a range of 'real world' conditions, such as when the operator changes the averaging value. The technique was however vulnerable to highly inaccurate focussing or abnormal downward displacement of the image. OCT-based quantification of vitreous activity is a promising alternative to current subjective clinical estimates, with sufficient 'tolerance' to be used in routine clinical practice as well as clinical trials.
检测和评估葡萄膜炎的炎症活动对于该疾病的治疗至关重要，但目前仍主要依赖于主观的临床评估。光学相干断层扫描（OCT）测量玻璃体活性是替代临床玻璃体混浊评分的一种方法，已经通过了多项早期验证研究。在这项研究中，我们旨在评估“操作人员因素”对该技术变异性的影响，作为验证过程的一部分，并帮助评估其在“真实世界”应用中的适用性。玻璃体混浊指数通过计算每个扫描中玻璃体和外视网膜的反射率之间的比值来计算。测试了不同的扫描条件，并报告了它们对测量的影响。我们的研究结果表明，在一系列“真实世界”条件下，包括操作人员改变平均值时，OCT 测量的玻璃体活性的“定量成像”技术在正常受试者中具有良好的可靠性。然而，该技术容易受到聚焦极不准确或图像异常向下移位的影响。OCT 测量的玻璃体活性定量分析是当前主观临床评估的一种有前途的替代方法，具有足够的“可容忍性”，可用于常规临床实践以及临床试验。
