早产儿早期屈光参数特点及相关因素研究

Characteristics and associated factors of early refractive parameters in premature infants

目的探讨早产儿早期屈光参数特点及相关因素。方法病例对照研究。收集2018年5月至2019年2月于厦门市儿童医院眼科门诊行首次眼底筛查的早产儿,筛查时间为出生后4~6周或校正胎龄31~32周。单眼或双眼确诊为轻度早产儿视网膜病变(ROP)但未接受任何治疗的患儿为ROP组,并根据视网膜病变区域分为Ⅱ区亚组及Ⅲ区亚组;无ROP患儿为无ROP组。记录各组出生胎龄、出生体重、等效球镜度数、前房深度、玻璃体深度、眼轴长度、晶状体厚度及角膜屈光力进行比较,并对相关因素进行分析。统计学方法主要采用独立样本t检验、多元线性回归分析及Pearson相关分析。结果共纳入180例早产儿,男性101例,女性79例;出生胎龄为(30.82±3.10)周,检查时校正胎龄为(37.21±1.44)周;出生体重为(1 577.85±572.12)g。ROP组纳入90例(162只眼,其中85只右眼数据纳入分析),无ROP组纳入90例(90只右眼),两组出生胎龄、检查时校正胎龄、出生体重差异均无统计学意义(均P>0.05)。ROP组等效球镜度数为(1.90±1.39)D,非ROP组等效球镜度数为(3.04±1.88)D,ROP组等效球镜度数更小,差异有统计学意义(t=-4.653,P<0.01)。ROP组的前房深度为(1.82±0.23)mm,晶状体厚度为(4.54±0.18)mm,角膜屈光力为(43.99±0.99)D;无ROP组的前房深度为(1.91±0.94)mm,晶状体厚度为(4.23±0.50)mm,角膜屈光力为(43.72±0.92)D;ROP组前房更浅,晶状体更厚,角膜屈光力更高,差异均有统计学意义(均P<0.01)。ROP组中Ⅱ区亚组(48只右眼)及Ⅲ区亚组(37只右眼)的角膜屈光力分别为(43.92±0.78)、(43.39±1.05)D,等效球镜度数分别为(2.08±0.95)、(2.52±1.12)D,Ⅱ区亚组的角膜屈光力更高、等效球镜度数更小,差异均有统计学意义(均P<0.05)。多元线性回归分析显示早产儿出生体重、出生胎龄、角膜屈光力是等效球镜度数的影响因素(P<0.01),Pearson相关分析显示早产儿出生胎龄、出生体重与等效球镜度数呈正相关(r=0.182、0.223),角膜屈光力与等效球镜度数呈负相关(r=-0.125;均P<0.05)。结论早产儿出生胎龄越大、出生体重越重,等效球镜度数也越大。轻度ROP患儿的屈光参数具有前房浅、晶状体厚、角膜屈光力高、等效球镜度数小的特点,等效球镜度数与ROP病情发展密切相关。

Objective To investigate the characteristics and associated factors of early refractive parameters in premature infants.Methods Case-control study.Premature infants who underwent the first fundus screening in the ophthalmic clinic of Xiamen children′s Hospital from May 2018 to February 2019 were collected.The screening time was 4 to 6 weeks after birth or corrected gestational age from 31 to 32 weeks.The premature infants who were diagnosed with mild retinopathy of prematurity(ROP)in one eye or both eyes but did not receive any treatment were divided into ROP group and divided into zoneⅡsubgroup and zoneⅢsubgroup according to the region of ROP;the premature infants without ROP were divided into non-ROP group.The gestational age,birth weight,spherical equivalent,anterior chamber depth,vitreous depth,axial length,lens thickness and corneal refractive power were recorded and compared.Independent sample t-test,multiple linear regression analysis and Pearson correlation analysis were used.Results A total of 180 premature infants,101 males and 79 females,with gestational age of(30.82±3.10)weeks,corrected gestational age of(37.21±1.44)weeks and birth weight of(1577.85±572.12)g were included in this study.Ninety premature infants were included in the ROP group(162 eyes,of which 85 right eyes were included in the analysis)and 90 in the non-ROP group(90 right eyes).There was no significant difference in the distribution of gestational age,birth weight and corrected gestational age between the ROP group and non-ROP group(all P>0.05),but there was significant difference in the spherical equivalent between the two groups[(1.90±1.39)D vs.(3.04±1.88)D,t=-4.653,P<0.01],and ROP group was relatively smaller.In the ROP group,the anterior chamber depth was(1.82±0.23)mm,the lens thickness was(4.54±0.18)mm,and the corneal refractive power was(43.99±0.99)D.In the non-ROP group,the anterior chamber depth was(1.91±0.94)mm,the lens thickness was(4.23±0.50)mm,and the corneal refractive power was(43.72±0.92)D.The difference between the two groups was statistically significant(all P<0.01).In ROP group,the anterior chamber depth was shallower,the lens was thicker,and the corneal refractive power was higher.In ROP group,the corneal refractive power of 48 right eyes in zoneⅡsubgroup and 37 right eyes in ZoneⅢsubgroup were(43.92±0.78)D and(43.39±1.05)D respectively,and the spherical equivalent were(2.08±0.95)D and(2.52±1.12)D respectively.The corneal refractive power of zoneⅡsubgroup was higher and the spherical equivalent was smaller,and the differences were statistically significant(all P<0.05).Multiple regression analysis showed that birth weight,gestational age and corneal refractive power were the influencing factors of spherical equivalent(P<0.01).The results of Pearson correlation analysis showed that the gestational age(r=0.182),birth weight(r=0.223)and corneal refractive power(r=-0.125)of premature infants were closely related to the spherical equivalent(all P<0.05).Conclusions In premature infants,the larger spherical equivalent is related to greater gestational age and heavier birth weight.The refractive parameters of mild ROP are characterized by shallow anterior chamber,thick lens,high corneal refractive power and small spherical equivalent.The spherical equivalent is closely related to the development of ROP.