Brien Holden Institute of Optometry and Vision Sciences, LV Prasad Eye Institute, Kallam Anji Reddy Campus, Road No-2, Banjara Hills, Hyderabad, 500034, India.
Cont Lens Anterior Eye. 2019 Apr;42(2):226-228. doi: 10.1016/j.clae.2018.10.001. Epub 2018 Oct 15.
Nanophthalmos is rare developmental ocular condition characterized by a small eye with short axial length, high hyperopia and high lens to eye volume ratio due to arrested development of eye ball as a result of scleral inelasticity.
A 33 year old woman who presented with a complaint of blurring of distance and near vision in both eyes since childhood came to LV Prasad Eye Institute on July 2017. Best corrected visual acuity was 20/60 using soft contact lens +23.50 diopters for the right and left eyes. Axial lengths of two eyes were markedly shortened along with steep corneal curvatures. Visante anterior segment ocular coherence tomography showed a steep (convex) corneo-scleral junction (CSJ) which might be the reason for ill-fitting with conventionally estimated soft contact lens (SCL) parameters. Finally, selection of the customized hydrogel soft contact lens base curve close to flatter corneal curvature and small diameter showed characteristics of optimal lens fit.
The corneo-scleral junction profile plays significant role in soft contact lens fitting. An eye with a profile of convex CSJ would require a lens with steeper curvature compared to conventional measurements. Cases of nanophthalmos would require observation of the profile with the help of optical coherence tomography in addition to measurement of corneal curvature prior to fitting soft contact lenses.
先天性眼球小症是一种罕见的眼部发育异常疾病，其特征为眼球小、眼轴短、高度远视以及晶状体与眼球体积比高，这是由于眼球发育受阻导致巩膜缺乏弹性所致。
一名 33 岁女性自幼出现双眼远近视力模糊，于 2017 年 7 月就诊于 LV 普拉沙德眼科医院。右眼和左眼最佳矫正视力分别为 20/60 和 20/63，软性隐形眼镜+23.50 屈光度可矫正。双眼眼轴明显缩短，伴陡峭的角膜曲率。Visante 眼前节光学相干断层扫描显示陡峭（凸面）的角巩膜交界处（CSJ），这可能是软性隐形眼镜（SCL）参数常规估计不适合的原因。最终，选择基弧更平坦和直径较小的定制亲水软性隐形眼镜，显示出最佳的镜片适配特征。
角巩膜交界处形态对软性隐形眼镜适配具有重要作用。与传统测量相比，具有凸面 CSJ 形态的眼睛需要曲率更陡的镜片。在为先天性眼球小症患者适配软性隐形眼镜之前，除了测量角膜曲率外，还需要借助光学相干断层扫描观察其角巩膜交界处形态。
