Kehler Lori Ann F, Fraine Lisa, Lu Pengcheng
*OD, FAAO †CO, COMT ‡MS Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, Tennessee (LAFK, LF); and Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, Tennessee (PL).
Optom Vis Sci. 2014 May;91(5):528-32. doi: 10.1097/OPX.0000000000000245.
It has been suggested that children perceptually adapt to changes in retinal image size in the presence of anisometropia and therefore do not display clinically significant aniseikonia. However, given that early methods of eikonometry were not child-friendly, the prevalence of this condition in children is poorly understood. Retinal image size differences may be relevant in the discussion of amblyogenesis. The computer-based Aniseikonia Inspector Version 3 (AI3) uses a simple, forced-choice method and includes calibration for heterophoria. The present study is designed to evaluate AI3 by measuring background and induced aniseikonia in children aged 5 to 13 years.
All subjects were present for a standard-of-care eye examination and had at least 20/40 best-corrected visual acuity and no history of strabismus or amblyopia. Trials of AI3 were performed in the vertical direction only, using the 12-point test, and two trials were recorded. Each subject was randomized to have a 4% size lens added to either the right eye or the left eye. Two trials were performed in this manner, followed by two more trials with the size lens over the alternate eye.
Eighteen children were enrolled; three subjects were not able to complete testing because of lack of attention or understanding. Results from each condition (background aniseikonia, induced aniseikonia OD, and induced aniseikonia OS) were averaged for each patient. With the 4% size lens over the OD, mean aniseikonia measured -3.83%. With the 4% size lens over the OS, mean aniseikonia measured 4.29%.
Most children were able to complete aniseikonia testing with AI3. Background aniseikonia was clinically insignificant (0.59%), and induced aniseikonia measurements were close to expected values using a 4% size lens. Aniseikonia Inspector Version 3 appears to be a useful means for measuring aniseikonia in a normal pediatric population. Further study in children with anisometropia is needed.
有人提出，在存在屈光参差的情况下，儿童会在感知上适应视网膜图像大小的变化，因此不会表现出具有临床意义的影像不等。然而，鉴于早期的视网膜像大小测量方法对儿童不友好，人们对这种情况在儿童中的患病率了解甚少。视网膜图像大小差异可能与弱视成因的讨论相关。基于计算机的Aniseikonia Inspector版本3（AI3）使用一种简单的强制选择方法，并包括对隐斜视的校准。本研究旨在通过测量5至13岁儿童的背景影像不等和诱发影像不等来评估AI3。
所有受试者均接受了标准的眼科检查，最佳矫正视力至少为20/40，且无斜视或弱视病史。仅在垂直方向使用12点测试进行AI3试验，并记录两次试验结果。每个受试者被随机分配在右眼或左眼上加一个4%大小的透镜。以这种方式进行两次试验，然后在另一只眼睛上加大小透镜再进行两次试验。
招募了18名儿童；3名受试者因注意力不集中或理解能力不足而无法完成测试。对每位患者每种情况（背景影像不等、右眼诱发影像不等和左眼诱发影像不等）的结果进行平均。右眼上加4%大小的透镜时，平均影像不等测量值为-3.83%。左眼上加4%大小的透镜时，平均影像不等测量值为4.29%。
大多数儿童能够使用AI3完成影像不等测试。背景影像不等在临床上无显著意义（0.59%），使用4%大小的透镜时诱发影像不等测量值接近预期值。Aniseikonia Inspector版本3似乎是测量正常儿童群体影像不等的一种有用方法。需要对屈光参差儿童进行进一步研究。
