Is it Myopia or Glaucoma? Clinical Tools to Identify the Disease

青光眼是一种慢性、进行性的眼部疾病，其特征在于视网膜神经节细胞损伤，其表现为视神经盘的特征性外观和视野丧失。它是全球第二大不可逆性失明的最常见原因。据估计，2013年青光眼患者总数为6400万人，预计到2020年将增加到8000万人。近视或近视是一种远处物体看起来模糊的情况。当光线聚焦在视网膜前方时发生近视，通常与眼轴长度超过正常值有关。近视的患病率从2010年的约14亿迅速增加到2050年的估计50亿。近视患者患青光眼的可能性是非近视患者的2.5倍。然而，临床上的挑战是，近视的视神经乳头模仿青光眼对视盘的损害，这使得很难诊断近视患者的青光眼。同时近视的视盘可能被误认为青光眼，甚至导致健康近视者对青光眼的过度诊断和过度治疗。本研究的目的是准确区分近视伴青光眼和不伴青光眼。我们假设，通过光学相干断层扫描（OCT）和OCT血管造影（OCTA）识别的近视性视盘的独特特征可用于区分近视眼伴和不伴青光眼。OCT和OCTA是两种视网膜成像模式，广泛用于常规眼科检查，并被认为是青光眼和其他视网膜疾病的治疗标准。OCT用于可视化和测量视网膜的不同层，而OCTA可视化脉络膜和视网膜血管。视乳头旁萎缩带是视乳头周围的脉络膜视网膜萎缩带，OCT可将视乳头旁萎缩带分为视乳头旁萎缩带-α、视乳头旁萎缩带-β和视乳头旁萎缩带-γ三个亚型，而临床检查无法将视乳头旁萎缩带分为三个亚型。最近的研究表明，视乳头旁萎缩带-β与近视和青光眼的相关性更强，视乳头旁萎缩带-γ与近视和非青光眼的相关性更强。我们假设，视乳头旁萎缩沿着其他OCT参数，如视盘倾斜、椭圆度指数、中心凹至视盘角度和距离、视神经乳头脉络膜厚度和OCTA测量值可用于区分青光眼近视眼和无青光眼近视眼。如果我们的假设是正确的，那么这些OCT和OCTA参数可以用于开发临床决策支持算法，以改善近视患者青光眼的检测。最后，这些新的临床决策支持工具将有助于预防近视患者因青光眼导致的功能障碍和失明，另一方面将有助于防止健康近视患者的过度诊断和过度治疗，提高生活质量并降低过度治疗导致的医疗保健费用。

Glaucoma is a chronic, progressive eye disease, characterized by retinal ganglion cell damage, which presents with a pathognomonic appearance of the optic disc and visual field loss. It is the second most common cause of irreversible blindness worldwide. The total number of people with glaucoma was estimated to be 64 million in 2013 and is expected to increase to 80 million by 2020.Myopia or nearsightedness is a condition where distant objects appear blurry. Myopia occurs when light is focused anterior to the retina and is usually associated with axial length above the norm. The prevalence of myopia is rapidly increasing from ~1.4 billion worldwide in 2010, to an estimated 5 billion by 2050.Individuals with myopia are 2.5 times more likely to have glaucoma than those without myopia. However, the clinical challenge is that the myopic optic nerve head mimics glaucomatous damage to the optic disc, which makes it difficult to diagnose glaucoma in myopes. At the same time a myopic optic disc may mistakenly be interpreted as glaucoma and even result in overdiagnosis and overtreatment of glaucoma in healthy myopes.The objective of this study is to differentiate accurately between myopia with and without glaucoma. We hypothesize that unique features of the myopic optic disc, identified by optical coherence tomography (OCT) and OCT-Angiography (OCTA) could be used to differentiate between myopic eyes with and without glaucoma.OCT and OCTA are two retinal imaging modalities that are used extensively in routine ophthalmic examinations and considered the standard of care for management of glaucoma and other retinal diseases. OCT is used to visualize and measure different layers of the retina, while OCTA visualizes choroidal and retinal vasculature. The parapapillary atrophy zone is a chorioretinal atrophy zone around the optic disc, which can be categorized into subtypes parapapillary atrophy zone-α, zone-β and zone-γ by OCT but not by clinical examination. Recent studies suggest that parapapillary atrophy zone-β is more strongly associated with myopia and glaucoma and parapapillary atrophy zone-γ with myopia and no glaucoma. We hypothesize that parapapillary atrophy along with other OCT parameters such as optic disc tilt, ovality index, fovea to disc angle and distance, optic nerve head choroidal thickness and OCTA measurements could be used to differentiate between myopic eyes with glaucoma and myopic eyes without glaucoma. If our hypothesis is correct, these OCT and OCTA parameters can then be used to develop clinical decision support algorithms to improve detection of glaucoma in individuals with myopia. Finally, these new clinical decision support tools will help to prevent functional impairment and blindness caused by glaucoma in patients with myopia and on the other hand will help to prevent overdiagnosis and overtreatment in healthy myopes, improve quality of life and reduce health care costs due to overtreatment.