中国青少年近视患者水平视网膜相对周边屈光度和散光分量曲线类型研究

摘要

Background The relationship between the relative peripheral refraction (RPR) of retina and the development of myopia has recently become the concerns for researchers.However,there have been few data on the RPR and the astigmatic vector patterns in myopic populations.It is needed to study the RPR and the astigmatic vector patterns in the Chinese young myopic subjects.Objective The RPR and astigmatic vector patterns were determined in Chinese young myopic subjects.Methods This prospective study comprised 301 Chinese young myopic subjects who visited ophthalmology department of Peking University People's Hospital from June 2014 to October 2015.Horizontal peripheral refractions were measured in 5° steps out to 30° eccentricity in both the nasal and temporal visual fields using Grand Seiko WAM-5500 autorefractor.Only data from the right eyes were used for analyses.Spherical equivalent refractions (SER) at each angular position were calculated and the relative peripheral refractive errors (expressed as defocus) were determined by subtracting the peripheral SER from the central SER.The RPR was categorized based on the shapes of peripheral refractive curves and the relative positions in the nasal or temporal retinal regions.Astigmatism at each angle was decomposed into J0 and J45 vectors based on Fourier decomposition and the curve patterns for the astigmatic vectors were examined.This study adhered to the tenets of the Declaration of Helsinki and was approved by the Human Research Ethics Committee of Peking University People's Hospital.Results Seven types of relative peripheral refractive curves were identified (retinal regions):negative defocus,temporal positive defocus and nasal flatness,temporal positive and nasal negative defocus,temporal flatness and nasal negative defocus,flatness in both temporal and nasal retina,temporal negative defocus and nasal flatness,and positive defocus.Patterns of astigmatic vector J0 and J45 were divided into 9 categories.The rate of type Ⅰ RPR was significantly greater in the moderate and high myopia group than that in the low myopia group (x2 =26.770,P＜0.05).The rate of type Ⅲ was significantly greater in the low myopia group than that in the moderate and high myopia group (x2 =12.500,P＜0.05).Conclusions The distributions of RPR were significantly different between low myopia group and moderate and high myopia group.There were nasal-temporal asymmetries for the absolute values of astigmatism along peripheral horizontal meridian.The absolute values of astigmatism in the nasal retinal regions were increased with the increase of fixation angles (except for the value at nasal 10°).%背景 视网膜相对周边屈光度(RPR)状态与近视进展的关系近年来成为研究的热点,目前尚缺乏对中国近视人群中视网膜RPR状态及散光分量的研究.因此,有必要针对中国青少年近视患者的视网膜RPR类型及散光分量进行分型研究. 目的 研究中国青少年近视患者视网膜RPR和散光分量的曲线类型.方法 选取2014年6月至2015年10月在北京大学人民医院眼科就诊的青少年近视患者301例301眼.以5°作为间隔,采用WAM-5500型开放视野红外验光仪采集从水平视野鼻侧30°至颞侧30°的周边屈光度数据.仅选取右眼数据进行分析.计算各个角度的等效球镜度(SER),用中央SER减去水平周边SER即为视网膜RPR(以离焦表示).依据视网膜RPR曲线的不同形态及鼻侧与颞侧的相对关系将视网膜RPR整理分型.采用傅里叶分解法将各个角度的散光分解为J0和J45分量,分析散光分量的曲线类型.结果 视网膜RPR曲线可分为7种类型,分别为负离焦型、颞侧正离焦鼻侧平坦型、颞侧正离焦鼻侧负离焦型、颞侧平坦鼻侧负离焦型、平坦型、颞侧负离焦鼻侧平坦型和正离焦型.散光分量Jo和J45可分为9型.中高度近视在Ⅰ型RPR(负离焦型)中的分布明显高于低度近视,差异有统计学意义(X2=26.770,P＜0.05);低度近视在Ⅲ型RPR(颞侧正离焦鼻侧负离焦型)中的分布明显高于中高度近视(X2=12.500,P＜0.05). 结论 低度近视与中高度近视的RPR曲线类型分布存在明显差异.散光绝对值在水平方向周边区域呈现鼻侧、颞侧不对称性.在视网膜鼻侧,随着注视角度的增加,其所对应的散光绝对值呈现逐渐增加的趋势(鼻侧10°除外).