Khokhar Sudarshan, Takkar Brijesh, Agarwal Esha, Gaur Nripen, Ravani Raghav, Venkatesh Pradeep
Retina and Uvea Services, Dr R P Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.
Int Ophthalmol. 2018 Dec;38(6):2427-2434. doi: 10.1007/s10792-017-0745-6. Epub 2017 Oct 24.
To evaluate changes in the anterior segment of myopic eyes and assess anterior biometry as a function of axial length (AL).
Retrospective investigational study.
Patients evaluated for phakic intraocular lens surgery at a tertiary eye care centre.
Patients with corrected visual acuity > 20/40 and AL > 24.5 mm were included in the study. Posterior staphyloma and maculopathy were ruled out in all the patients, and 176 eyes were included for analysis. AL was measured with partial coherence interferometry, while keratometry, central corneal thickness (CCT), anterior chamber depth (ACD), and horizontal white to white (WTW) were measured with slit-scanning topography. Group 1 included 55 eyes with AL < 26.5 mm, group 2 had 57 eyes with AL between 26.5 and 28.5 mm while group 3 had 64 eyes with AL > 28.5 mm.
Correlation of AL with anterior biometry.
The mean AL of the study eyes was 27.88 + 2.14 mm. The mean values of ACD (2.99 mm), CCT (0.52 mm), WTW (11.68 mm), and keratometry (43.62 D) were within the normal range. Overall, very weak correlations could be established between AL and CCT (R = 0.17, p = 0.02), AL and keratometry (R = - 0.28, p < 0.001), and AL and WTW (R = 0.22, p = 0.002), while ACD did not relate to AL significantly. The ACD and CCT did not relate significantly to AL in any of the three groups. Keratometry had a weak negative relation with AL in groups 1 and 2, while WTW had a weakly positive relation with AL in group 2 only. No variable had any significant relation with AL in group 3.
There is disproportionate elongation of the eyeball in myopic patients with very weak or no correlation between anterior biometry and AL. This discord is more in longer eyes. Such a scenario can be challenging to a refractive surgeon treating highly myopic eyes and needs further evaluation.
评估近视眼眼前节的变化，并根据眼轴长度（AL）评估眼前节生物测量参数。
回顾性研究。
在一家三级眼科护理中心接受有晶状体眼人工晶状体手术评估的患者。
纳入矫正视力>20/40且眼轴长度>24.5mm的患者。所有患者均排除后巩膜葡萄肿和黄斑病变，共纳入176只眼进行分析。使用部分相干干涉测量法测量眼轴长度，使用裂隙扫描地形图测量角膜曲率、中央角膜厚度（CCT）、前房深度（ACD）和水平白对白（WTW）。第1组包括55只眼，眼轴长度<26.5mm；第2组有57只眼，眼轴长度在26.5至28.5mm之间；第3组有64只眼，眼轴长度>28.5mm。
眼轴长度与眼前节生物测量参数的相关性。
研究眼的平均眼轴长度为27.88±2.14mm。前房深度（2.99mm）、中央角膜厚度（0.52mm）、水平白对白（11.68mm）和角膜曲率（43.62D）的平均值均在正常范围内。总体而言，眼轴长度与中央角膜厚度（R=0.17，p=0.02）、眼轴长度与角膜曲率（R=-0.28，p<0.001）以及眼轴长度与水平白对白（R=0.22，p=0.002）之间可建立非常弱的相关性，而前房深度与眼轴长度无显著相关性。在三组中的任何一组中，前房深度和中央角膜厚度与眼轴长度均无显著相关性。在第1组和第2组中，角膜曲率与眼轴长度呈弱负相关，而仅在第组2中，水平白对白与眼轴长度呈弱正相关。在第3组中，没有变量与眼轴长度有任何显著相关性。
近视患者眼球存在不成比例的伸长，眼前节生物测量参数与眼轴长度之间相关性非常弱或无相关性。这种不一致在眼轴较长的眼中更为明显。这种情况对于治疗高度近视眼的屈光手术医生来说可能具有挑战性，需要进一步评估。
