文章来源：以下文章来源于青宁盟之声 ，作者青柠盟之声
Effect of reading with a mobile phone and text on accommodation in young adults
青年人中阅读手机文本和阅读纸质文本对于调节反应的影响
Graefe's Archive for Clinical and Experimental Ophthalmology（IF=2.349）
Accepted: 15 December 2020
Xintong Liang1# · Shifei Wei1# · Shi-Ming Li1 · Wenzai An1 · Jialing Du1 · Ningli Wang1*
Corresponding author:
Prof. Ningli Wang,Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, NO.1 Dongjiaominxiang Street, Dongcheng District, Beijing,China, 100730; Phone: 8613511026669; Fax number: (086) 01058269920; Email address: wningli@vip.163.com
Background 背景
Myopia has become an important public health issue worldwide, especially in Asian countries, and is a major cause of correctable visual impairment. The increasing prevalence of myopia is thought to be linked to the environment, such as intensive education, more near work and less time spent outdoors. Several studies have reported that near work is a vital contributor to myopia, but the exact reasons why near work exacerbates myopia are not well understood. This has attracted the interest of many researchers,and they have tried to determine the possible mechanisms by which periods of prolonged near work could result in myopia. Different mechanisms have been found to proposed, including accommodation error during near work (which means a lag in accommodation when the accommodation response is unable to meet the dioptric demand) and the small transient myopic far point shift immediately after long-term near work. These two mechanisms are thought to be key factors in myopia progression. 近视已经成为世界范围内重要的公共卫生问题，尤其是在亚洲国家，并且是可逆性视力损害的主要原因。近视患病率的增加与环境因素有关，例如加大的教育压力，近距离工作和减少的户外活动时间。几项研究认为，近距离工作是引起近视发生发展的重要原因，但近距离工作引起近视的确切机制尚不清楚。这引起了许多研究人员的兴趣。目前研究人员已经提出了几种不同的机制，包括近距离工作时的调节滞后（即在调节反应无法满足屈光需求时出现调节滞后）以及长时间近距离阅读后引起的短暂性远点漂移。这两种机制被认为是近视进展的关键因素。 With the development of digital devices in recent years, computers, smart phones and tablets have been argued to play a role in myopia progression. thus, children are now exposed to another potential environmental risk factor for myopia-digital screen time. Some previous studies showed that the use of computers was significantly associated with the prevalence of myopia and that there was more myopic refractive error in children 5–16 years old. However,there is a lack of consistent results of an association between screen time and myopia development. Several studies reported that the number of hours per day playing with electronic devices was not associated with myopia. Therefore,this is a current issue. With the increasing shift from printed to electronically produced text over the past three decades, many previous studies of NITM were carried out in the late 90s or early 2000's using printed text accommodative stimuli, so it is important to see if the shift to electronic displays has altered the accommodative behaviour. Our study wanted to examine whether there is a difference between reading with a digital screen and a traditional book text on accommodation responses and myopia.The type of reading with a phone screen or a book text has not been assessed interms of the differences in accommodation responses.近年来，随着数字时代的发展，计算机，智能手机和平板电脑等电子产品被认为在近视发展中起着重要作用。因此，儿童近视眼的发生面临着另一种潜在的环境危险因素即电子产品使用时间。先前的一些研究表明，计算机的使用与近视的患病率显着相关，并且在5至16岁的儿童中，近视的发生率更高。但是，在电子产品使用和近视发展之间的关系并没有得到一致的研究结果。有的研究认为，每天玩电子设备的小时数与近视无关。在过去的三十年中，关于NITM的许多研究都是在90年代末或2000年代初使用印刷文本调节刺激进行的，随着印刷文本到电子文本时代的转变，重要的是要了解电子产品时代的到来是否改变了调节行为。我们的研究旨在研究阅读电子产品与传统书籍对于调节反应的影响是否不同。目前尚未有研究评估过使用手机阅读和使用文本阅读对于调节反应之间的差异。 Therefore,the aim of this study was to investigate the effect of reading with a mobile phone and book text on the magnitude of NITM and its decay time and accommodative lags.因此，我们的研究目的是探索阅读手机和阅读文本对NITM、回退时间以及调节滞后的影响。
Methods 方法
研究共纳入31名年轻成人，采用开放式自动验光仪WAM-5500进行等效球镜度数的测量，任务模式分别为阅读手机和阅读文本两种，阅读距离均为33cm。受试者平均年龄为24.35±1.80。每一位受试者在基线测量前首先进行医学验光，配戴框架眼镜对屈光度进行了足矫。 接下来所有受试者被要求在一个完全黑暗的房间里5分钟以放松睫状肌。5分钟后打开灯，使受试者坐在自动验光仪的前面，观看4m远处的大小为20/30 Snellen字母，同时盖住左眼，测量受试者右眼的基线屈光度。以0.2秒的时间间隔进行了50次测量，平均值为受试者看远时的基线等效球镜度数。然后受试者随机抽取阅读任务，阅读手机或阅读文本40分钟，阅读距离为33cm。检查员每5分钟测量一次受试者的实际阅读距离，以确保其在任务期间的一致性。此外，还要求受试者在任何时候都尽可能清晰地看到这些单词。完成40分钟的阅读任务后，立即进行任务后的调节反应的测量。指示受试者将下巴放在自动折射仪的托上，观看眼前33cm处的近视力表，阅读视力表上最佳矫正视力的上一行，同时测量受试者此时的等效球镜度数10秒钟，然后，要求受试者再次立即盯住4 m远处的Snellen视标，并在180秒的时间内连续获取测量值（900次测量）。前10秒的平均值表示阅读任务后的屈光度。阅读后屈光度回退到基线值并维持10秒钟所需要的时间为回退时间。在两次阅读任务之间，受试者在一个完全黑暗的房间里休息至少10分钟。
Results 结果
无论在轻度近视组还是中度近视组，阅读文本比阅读手机引起的NITM值更大( 0.23±0.26 D vs 0.12±0.17 D)，但结果无统计学差异(P=0.082)。阅读文本的回退时间为70 (32, 180)秒，阅读手机的回退时间为60 (16, 154)，结果无统计学差异P=0.294。图1展示了阅读手机和阅读文本后NITM值的回退曲线。阅读手机和阅读文本引起的调节滞后值几乎相同( 1.31±0.64 vs 1.27±0.52, P=0.792)。
表1
图1
图2
图3
Discussion 讨论
In our study, the findings support our hypothesis that reading with text and a mobile phone had no significant difference on NITM and its decay and accommodative lags (P＞0.05).Several studies have confirmed that using electronic devices can increase the risk of myopia progression. For example, a previous study found that using a computer more than 3 hours per day was a high-risk factor for myopia in university students. Liu et al. supported that the more time individuals spent using smart phones and computers, the more myopic equivalent spherical refraction and longer axial length they had. Alarge longitudinal assessment in young adults was conducted by Fernández-Montero et al. and showed that exposure to computer use is associated with myopia development in a cohort of Spanish university graduates. However,the relationship between electronic devices and myopia have had mixed findings.A review written by Carla et al. showed that the prevalence, incidence or progression of myopia was not clearly associated with screen time. In our study, we observed the magnitudes of NITM and its decay and accommodative lags in reading with a mobile phone and text, and there were no significant differences between book and phone use. The results provide evidence that reading with a mobile phone and text have similar effects on the accommodation response, and both can increase the risk of myopia progression. Our research suggested that mobile phone use may not be a causal factor but may be a replacement for a different type of near work.在我们的研究中，这些发现支持我们的假设，即阅读文本和阅读手机对NITM及其回退时间及调节滞后没有显着差异（P＞0.05）。多项研究已经证实，使用电子设备会增加近视发展的风险。例如，一项先前的研究发现，每天使用计算机超过3个小时是大学生近视的高风险因素。还有研究认为个人使用智能手机和计算机的时间越长，近视度数越高，眼轴长度越长。但也有一些研究认为电子产品使用与近视进展没有相关性。在我们的研究结果中，表明了阅读手机和阅读本文对调节反应具有相似的影响，并且两者都可能增加近视发展的风险。因此，使用电子产品相比较于文本阅读本身并不会加快近视进展，而是阅读手机作为近距离工作的一种类型从而影响着近视的发生发展。
Conclusion 结论
In summary, reading with text tasks caused a larger NITM, longer decay time and greater accommodative lags than reading with a mobile phone, but the small differences were not clinically significant.Current evidence suggests that the impact of mobile phone use on accommodative responses is similar to that of text use as a type of near work. As conventional educational reading or writing with paper and a pen is gradually replaced by digital screen time and with more recreational screen time in adolescents, effective measures should be taken to limit the use time of digital devices.总而言之，与阅读手机相比，阅读文本可导致更大的NITM，更长的回退时间，但两者之间的差异并没有显著性。当前的证据表明，使用手机对调节反应的影响类似于阅读文本，两者均为近距离工作的不同类型。随着传统的用纸和笔进行的教育性阅读或书写逐渐被数字屏幕教学所取代，并且在青少年中电子产品用于娱乐性质的越来越多，因此，应采取有效措施来控制电子产品的使用时间。
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