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在中国东南部不同角膜曲率的儿童中折射参数的分布和相关性
Si-Yuan He1, Ting He2, Meng-Yue Xu2
1The Second Clinical College, Zhejiang Chinese Medical University, Hangzhou 310053, Zhejiang Province, China.
International journal of ophthalmology
|April 19, 2024
概括
患有下角膜曲率 (CC) 的儿童近视性较少,但轴长度较长 (AL). 低CC可能会掩盖折射变化,在近视发作之前,AL增长更快.
科学领域:
- 眼科医生 眼科 眼科
- 儿科光学测量 儿科光学测量
- 角质生物力学 角质生物力学
背景情况:
- 角膜曲率 (CC) 是折射状态的一个关键因素.
- 了解学龄儿童中CC分布对于近视管理至关重要.
- 以前的研究还没有完全阐明CC和折射误差在这个人口群中的关系.
研究的目的:
- 分析与学龄儿童角膜曲率相关的折射状态的分布.
- 调查角膜曲率与折射状态之间的相关性,包括轴长和球形等价值.
- 为了比较具有较低角膜曲率 (LCC) 和较高角膜曲率 (HCC) 的儿童之间的折射参数.
主要方法:
- 一项对杭州2214名四年级学生的横截面研究.
- 测量包括未经校正的距离视敏度 (UCDVA),非cycloplegic折射,轴长 (AL) 和角膜曲率 (K1,K2).
- 儿童被分为LCC (CCR≥7.92) 和HCC (CCR<7.92) 组,并进一步划分为正常和长AL子组.
主要成果:
- 较低角膜曲率 (LCC) 组表现出更大的球体等价值 (SE) 和轴长 (AL) (P=0.013,P<0.001).
- 近视的患病率在LCC中为38%,在HCC中为44% (P<0.001),在LCC组中非近视儿童的比例更高 (62%对56%).
- 在非近视儿童中,LCC组的长期AL比例显着更高 (24%与0.012%相比;P<0.001),而SE变化与HCC组相比,AL增加的影响较小.
结论:
- 学校年龄的儿童与较低的角膜曲率有较低的查近视的发生率,但更长的轴长度.
- 较低的角膜曲率可以部分掩盖球形等效减小和轴向长度增长.
- 在低CC的儿童中,轴长度增长更明显,在近视发作之前观察到更快的进展.
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