Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 251 Fukang Road, Nankai District, Tianjin, China.
Illinois College of Optometry, 3241 S, Michigan Ave, Chicago, IL, 60616, USA.
BMC Ophthalmol. 2021 Jun 10;21(1):256. doi: 10.1186/s12886-021-02001-6.
To evaluate the necessity of cycloplegia for epidemiological studies of refraction in Chinese young adults (aged 17-22 years) with dark irises, and to compare the cycloplegic effects of 1% cyclopentolate and 0.5% tropicamide in them.
A total of 300 young adults (108 males and 192 females) aged 17 to 22 years (mean 19.03 ± 1.01) were recruited from Tianjin Medical University from November 2019 to January 2020. Participants were randomly divided into two groups. In the cyclopentolate group, two drops of 1% cyclopentolate eye drop were administrated (one drop every 5 min), followed by autorefraction and subjective refraction 30 to 45 min later. In the tropicamide group, four drops of 1% Mydrin P (Tropicamide 0.5%, phenylephrine HCl 0.5%) eye drop were given (one drop every 5 min), followed by autorefraction and subjective refraction 20 to 30 min later. The participants and the examiners were masked to the medication. Distance visual acuity, intraocular pressure (IOP), non-cycloplegic and cycloplegic autorefraction (Topcon KR-800, Topcon Co. Tokyo, Japan), non-cycloplegic and cycloplegic subjective refraction and ocular biometry (Lenstar LS-900) were performed.
The values of spherical equivalent (SE) and sphere component were significantly different before and after cycloplegia in the cyclopentolate group and the tropicamide group (p < 0.05). The mean difference between noncycloplegic and cycloplegic autorefraction SE was 0.39 D (±0.66 D) in the cyclopentolate group and 0.39 D (±0.34 D) in the tropicamide group. There was no significant difference in the change of SE and sphere component after cycloplegia between the cyclopentolate group and the tropicamide group (p > 0.05). In each group, no significant difference was found between autorefraction and subjective refraction after cycloplegia (p > 0.05). We also found that more positive or less negative cycloplegic refraction was associated with the higher difference in SE in each group.
Cycloplegic refractions were generally more positive or less negative than non-cycloplegic refractions. It is necessary to perform cycloplegia for Chinese young adults with dark irises to obtain accurate refractive errors. We suggest that cycloplegic autorefraction using tropicamide may be considered as a reliable method for epidemiological studies of refraction in Chinese young adults with dark irises.
The study was registered on September 7, 2019 (Registration number: ChiCTR1900025774 ).
为评估虹膜颜色较深的中国年轻成年人（17-22 岁）在近视流行病学研究中是否需要睫状肌麻痹，并比较 1%环戊通和 0.5%托吡卡胺在他们中的睫状肌麻痹效果。
2019 年 11 月至 2020 年 1 月，我们从天津医科大学招募了 300 名年龄在 17 至 22 岁（平均 19.03±1.01 岁）的年轻人（男 108 名，女 192 名）。参与者被随机分为两组。在环戊通组中，给予 2 滴 1%环戊通滴眼液（每 5 分钟 1 滴），30 至 45 分钟后进行自动折射和主观折射。在托吡卡胺组中，给予 4 滴 1% Mydrin P（托吡卡胺 0.5%，盐酸苯肾上腺素 0.5%）滴眼液（每 5 分钟 1 滴），20 至 30 分钟后进行自动折射和主观折射。参与者和检查者均对药物治疗情况进行了盲法。测量距离视力、眼内压（IOP）、非睫状肌麻痹和睫状肌麻痹自动折射（Topcon KR-800，Topcon 公司，东京，日本）、非睫状肌麻痹和睫状肌麻痹主观折射和眼生物测量（Lenstar LS-900）。
在环戊通组和托吡卡胺组中，睫状肌麻痹前后球镜等效（SE）和球镜成分值均有显著差异（p<0.05）。环戊通组非睫状肌麻痹和睫状肌麻痹自动折射 SE 的平均差异为 0.39 D（±0.66 D），托吡卡胺组为 0.39 D（±0.34 D）。睫状肌麻痹后 SE 和球镜成分的变化在环戊通组和托吡卡胺组之间无显著差异（p>0.05）。在每组中，睫状肌麻痹后自动折射和主观折射之间无显著差异（p>0.05）。我们还发现，每组中睫状肌麻痹后的 SE 差值越大，正性或负性越小。
睫状肌麻痹后的折射通常比非睫状肌麻痹后的折射更正或更负。为了获得准确的屈光不正，有必要对虹膜颜色较深的中国年轻成年人进行睫状肌麻痹。我们建议使用托吡卡胺进行睫状肌麻痹自动折射，可作为中国虹膜颜色较深的年轻成年人近视流行病学研究的可靠方法。
该研究于 2019 年 9 月 7 日注册（注册号：ChiCTR1900025774）。
