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Prevalence of Myopia and Binocular Vision Dysfunctions in Microscopists

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Prevalence of Myopia and Binocular Vision Dysfunctions in Microscopists 国际眼科杂志摇 2018 年 7 月摇 第 18 卷摇 第 7 期摇 摇 http:/ / ies. ijo. cn 电话:029鄄82245172摇 摇 85263940摇 摇 电子信箱:IJO. 2000@ 163. com Original article · · Prevalence of myopia and binocular vision dysfunctions in microscopists 1 2,3 4 4 Rajeshwori Ngakhushi , Raju Kaiti , Sanjeev Bhattarai , Gulshan Bdr Shrestha 1 Reiyukai Eiko Masunaga Eye Hospital, Banepa 45210, Abstract AIM To determine the refractive and binocular vision Nepal 誗 : 2 status in clinical microscopists. Department of Ophthalmology, Dhulikhel Hospital, METHODS It was an observational and cross sectional Kathmandu University, Kavrepalanchowk 45200, Nepal 誗 : 3 hospital based study. One hundred and three Drishti Eye Care System, Kalanki 44620, Nepal 4 microscopists working at Tribhuvan University Teaching Department of Ophthalmology, B. P. Koirala Lions Centre for Hospital were recruited in the study. All subjects had a Ophthalmic Studies, Institute of Medicine, Tribhuvan comprehensive eye examination including static University, Kathmandu 44613, Nepal retinoscopy dynamic retinoscopy and orthoptic Correspondence to , : Raju Kaiti. Department of evaluation. Information about their visual symptoms Ophthalmology, Dhulikhel Hospital, Kathmandu University, associated with microscopy was also collected. RESULTS The prevalence of refractive error in this Kavrepalanchowk 45200, Nepal. rajukaiti@ gmail. com 誗 : Received: 2018-01-25摇 摇 Accepted: 2018-04-27 group of microscopists was 69. 90% . Majority of the subjects were myopic 68. 93% of total subjects with the ( ) 显微镜工作者近视和双眼视力障碍的患病率分 mean myopic error of - 1. 58 依 1. 89 D. Convergence 析 insufficiency was found in 61. 20% of the study , population. Prevalence of accommodative insufficiency 1 , 2 3 , 4 , Rajeshwori Ngakhushi Raju Kaiti Sanjeev Bhattarai and infacility were 41. 30% and 40. 06% respectively. 4 Gulshan Bdr Shrestha Fusional vergence was also reduced in this study 作者单位 1 尼泊尔 巴内帕 眼科 ( : 45210 , ,Reiyukai Eiko Masunaga population. The outcomes of this study were expected to 医院 2 尼泊尔 加德满都大学 图利凯尔 ; 45200 ,Kavrepalanchowk, , increase the awareness about the refractive and binocular 医院 眼科 3 尼泊尔 卡兰基 眼护系统 4 尼 , ; 44620 , ,Drishti ; 44613 vision anomalies among this population. 泊尔 加德满都 特里布文大学医学院 眼科 , , ,B. P. Koirala Lions CONCLUSION There was found to be increased 研究中心 誗 : ) prevalence of refractive error in clinical microscopists 通讯作者 , :Raju Kaiti. rajukaiti@ gmail. com especially myopia. Majority of them had vergence and accommodative anomalies. Most of the subjects reported 摘要 asthenopic symptoms associated with their microscopy 目的:测定临床显微镜工作者屈光和双眼视力状态。 work which may affect their work efficiency. , 方法:这是一项以医院为基础的观察性和横断面研究。 研 KEYWORDS microscopists refractive error 誗 : ; ; 究包括 位在特里布文教学医院工作的显微镜工作者。 instrumental myopia orthoptic asthenopic 103 ; ; 受试者均行全面的眼部检查,包括静态检影,动态检影和 DOI:10. 3980 / j. issn. 1672-5123. 2018. 7. 03 视轴评估。 收集受试者显微镜下视觉状态信息。 结果: 该组显微镜工作者屈光不正患病率为 。 Citation 69. 90% : Ngakhushi R, Kaiti R, Bhattarai S, Shrestha GB. 受试者近视,平均近视误差为 。 研 68. 93% -1. 58依1. 89 D Prevalence of myopia and binocular vision dysfunctions in 究发现 受试者汇聚功能不全。 调节不足与调节 Guoji Yanke Zazhi Int Eye Sci 61. 20% microscopists. ( ) 2018;18(7):1180-1183 功能不全的发病率分别为 和 。 研究人群 41. 30% 40. 06% 的融合性转向也有所降低。 INTRODUCTION 结论:研究发现,临床显微镜工作者屈光不正尤其是近视 efractive error is a condition where an unfocused image is 的患病率增加。 其中大多数有转斜和调节不足。 大多数 formed on the retina. Microscopy work, which involves 受试者视疲劳症状与其显微镜工作有关,这可能会影响他 R prolong near focus can lead to refractive error, oculomotor 们的工作效率。 imbalance and asthenopic symptoms. According to a study, 关键词:显微镜工作者;屈光不正;显微镜近视;视轴矫正; among 50 clinical microscopists, 60% of the subjects reported 视疲劳 [1] refractive errors . Heavy near work is the most important factor for higher incidence of myopia, poor convergence and 引用: 显微镜工 [2] Ngakhushi R, Kaiti R, Bhattarai S, Shrestha GB. exophoria . Near work is primary, environmental based 作者近视和双眼视力障碍的患病率分析 国际眼科杂志 [3] . 2018; factor in the aetiology and progression of myopia . Majority [4] 18(7):1180-1183 of people whose myopia progressed were law students , 1180 Int Eye Sci Vol. 18 No. 7 Jul. 2018摇 摇 http / / ies. ijo. cn , , , : Tel 029鄄82245172摇 85263940摇 摇 Email IJO. 2000@163. com : : [5] [6] Table 1摇 Normal value of positive fusional vergence PFV for cadets in the air force academy and microscopists . ( ) et al[7] distance and near According to a study by Fritzsche on 163 pathologists, 89% suffered from ametropia. Myopia was the most common Distance Near refractive error affecting 75. 50% of the cases. Blur 7-11 pd 14-20 pd Instrumental myopia is the over accommodation that occurs Break 15-23 pd 18-24 pd when looking through optical instruments, for example Recovery 8-12 pd 7-15 pd binoculars, telescopes, phoropter, auto refractor and Table 2 摇 Normal value of negative fusional vergence NFV ( ) microscopes, even though these devices render the image at for distance and near [8-10] optical infinity . This over accommodation can create an Distance Near imbalance between the accommodative and vergence system [11] Blur Not applicable 11-15 pd which potentially lead to myopia progression . Sustained Break 5-9 pd 19-23 pd and chronic accommodation can lead to vitreous chamber [12] Recovery 3-5 pd 10-16 pd elongation and myopia due to scleral stretching . Ninety four percent of subjects mentioned different kinds of [1] blur was reported. The value of +1. 50 D to + 2. 50 D was asthenopic symptoms . The association between prolonged [15] use of microscope and visual problems has been recognized for considered normal . The value of positive relative decades. However awareness about these problems is still accommodation ( PRA ) was measured by adjusting the ignored. In this study, we sought to determine the presence of phoropter at 40 cm with refractive correction in place. Subject refractive and binocular vision anomalies in a group of was asked to fixate N6 letters, minus power was added in 0. 25 D steps until first sustained blur was reported. The PRA Nepalese microscopists. We wanted to assess asthenopic and [15] visual symptoms associated with the near work and provide value of -1. 25 D to -3. 50 D was considered normal . awareness about their ocular health. Accommodative facility was assessed monocularly and SUBJECTS AND METHODS binocularly with flipper lens of + / -2. 00 D and recorded as A cross sectional hospital based study was conducted at B. P. number of cycle per minute ( cpm). Value equal to or less than 6 cpm and 3 cpm were considered as abnormal for Koirala Lions Centre for Ophthalmic Studies from November [15] 2014 to October 2015. A total of 103 subjects (53 female and monocular and binocular flipper test respectively . 50 male ) were enrolled from Pathology and Microbiology Horizontal vergence ranges at distance (6 m) and near (40 laboratories at Tribhuvan University Teaching Hospital. A cm) were measured with prism bar. Prism bar was placed verbal consent was taken from each subject for participation base out (BO) to measure positive fusional vergence (PFV) after explaining the objectives of the study, examination and base in ( BI ) to measure negative fusional vergence procedures and assuring that information collected was for (NFV). Normal value of positive fusional vergence ( Table 1 ) and negative fusional vergence ( Table 2 ) are as research purpose only and their privacy will be maintained. [16] The study was conducted in accordance with the Declaration of follows . Helsinki. Stereopsis was measured with help of Titmus vectographic Static retinoscopy was performed on all subjects using Heine plate (Stereo fly test with wirt rings) and Polaroid glasses in BETA 200 retinoscope. We followed the same criteria for seconds of arc. refractive error classification by Adams and McBrien. Information about subject蒺s age, refractive correction, work Refractive errors - 0. 25 DS to + 0. 75 DS ( spherical history, working hours and symptoms associated with via equivalent power) were classified as emmetropic, greater than microscopy work was collected a specially prepared + 0. 75 DS as hyperopic and less than - 0. 25 DS as questionnaire. [13] myopic . Dynamic retinoscopy was performed on non - All the clinical findings were entered in the standard study presbyopic subjects by monocular estimated method ( MEM) Performa. The results were depicted in the form of diagrams over distance correction in place. and tables by using computer data analysis software ( SPSS Both distant (6 m) and near (0. 4 m) heterophoria were 20. 0). Data was subjected to statistical analysis including t measured by using prism bar. Near point of convergence descriptive statistics, frequency analysis, paired - test and (NPC) was assessed with the help of royal air force ( RAF) bivariate Pearson correlations. RESULTS rule. NPC of less than 7. 6 cm was considered as reduced [14] convergence . Monocular and binocular amplitude of The mean age of the subjects was 29. 56依8. 82 (range from: accommodation ( AA ) was assessed on non - presbyopic 19-59)y. Their working duration ranges between 3mo to 40y subjects with the help of RAF rule. AA is considered as with the mean value of 7. 84y. They had been using reduced when it was less than age normal expected value. microscope 1 to 10h per day with an average working hours of The value of negative relative accommodation ( NRA) was 2. 59依2. 01h per day. measured by adjusting the phoropter at 40 cm with refractive The prevalence of refractive error in this group of n correction in place. Subject was asked to fixate N6 letters, microscopists was found to be 69. 90 % ( = 103). Myopia n plus power was added in 0. 25 DS steps until first sustained constituted about 98. 61% ( = 71) of the refractive error and 1181 国际眼科杂志摇 2018 年 7 月摇 第 18 卷摇 第 7 期摇 摇 http:/ / ies. ijo. cn 电话:029鄄82245172摇 摇 85263940摇 摇 电子信箱:IJO. 2000@ 163. com Table 4摇 Distribution of accommodative anomalies n Accommodative anomalies (92) Prevalence Higher lag of accommodation 28 30. 43% Lead of accommodation 4 4. 35% Accommodation insufficiency RE 38 41. 30% Accommodation insufficiency LE 32 34. 78% Accommodation excess 1 1. 08% Accommodative infacility 30 40. 06% RE: Right eye; LE: Left eye.
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