Department of Ophthalmology, University of Leicester, Leicester, UK.
Department of Ophthalmology, University of Leicester, Leicester, UK.
Lancet. 2015 Feb 26;385 Suppl 1:S14. doi: 10.1016/S0140-6736(15)60329-4.
Retinal development normally involves migration of the inner retinal layers away from the fovea, migration of the cone photoreceptors into the fovea, and elongation of the photoreceptors over time. This process is arrested prematurely in albinism. However, because retinal development continues at least until the age of 4 years, when development arrests in albinism is uncertain. In this study we outlined the time course of retinal development in children with albinism.
We studied 44 children with a diagnosis of albinism and 223 control participants. All participants were aged between 0 and 6 years. We obtained 219 mixed cross-sectional and longitudinal optical coherence tomography examinations in the albinism group and compared them with 558 control examinations. Retinal layer segmentation was performed with ImageJ software. Generalised linear mixed regression modelling was used to analyse group differences in retinal development.
In the albinism group, inner retinal layer migration from the fovea was delayed and arrested prematurely, resulting in a significantly thicker central macular thickness than in the control group (p<0·0001). Whereas the central macular thickness increased with age in the control group, in the albinism group it initially decreased with age as a result of continuing regression of the inner retinal layers (p=0·041). The perifoveal retinal thickness was significantly decreased in albinism from a reduction of both inner (p<0·0001) and outer (p<0·0001) retinal layer thicknesses. There was evidence that the photoreceptor layers across the fovea were elongating in albinism, albeit at a reduced rate, compared with the control group. This difference was most apparent for the foveal photoreceptor inner segment (p=0·001).
Our findings show that perturbations exist in several aspects of retinal development including the migration and differentiation of the neuronal cells within the retina. We showed continuing regression of the inner retinal layers and elongation of the photoreceptor layers suggesting residual plasticity of the developing albino retina. This finding is important because treatment at the earliest stages of the condition might normalise retinal development and optimise vision.
UK Medical Research Council (grant number MR/J004189/1), Ulverscroft Foundation, National Eye Research Centre, Nystagmus Network UK.
视网膜的正常发育包括内层视网膜从黄斑区移开、视锥细胞向黄斑区迁移以及感光细胞随时间延长而变长。白化病患者的这一过程会过早停止。但是，由于视网膜的发育至少持续到 4 岁，因此白化病患者的发育停止时间尚不确定。本研究旨在阐述白化病患儿的视网膜发育过程。
我们研究了 44 名被诊断为白化病的患儿和 223 名对照组参与者。所有参与者的年龄均在 0 至 6 岁之间。我们在白化病组中获得了 219 次混合横断面和纵向光学相干断层扫描检查，并将其与 558 次对照组检查进行了比较。使用 ImageJ 软件进行视网膜层分割。使用广义线性混合回归模型分析两组间视网膜发育的差异。
在白化病组中，内层视网膜从黄斑区的迁移被延迟并过早停止，导致中央黄斑厚度明显增厚，明显大于对照组（p<0·0001）。在对照组中，中央黄斑厚度随年龄增加而增加，而在白化病组中，由于内层视网膜持续退化，中央黄斑厚度最初随年龄减少（p=0·041）。在白化病中，由于内（p<0·0001）和外（p<0·0001）视网膜层厚度的减少，旁中心视网膜厚度显著降低。有证据表明，与对照组相比，在白化病中，穿过黄斑的光感受器层确实在伸长，尽管速度较慢。这种差异在黄斑中心凹光感受器内节（foveal photoreceptor inner segment）最明显（p=0·001）。
我们的研究结果表明，视网膜发育的多个方面存在异常，包括视网膜内神经元细胞的迁移和分化。我们发现内层视网膜持续退化和感光细胞层伸长，表明发育中的白化病视网膜仍具有一定的可塑性。这一发现很重要，因为在疾病的早期阶段进行治疗可能会使视网膜发育正常化并优化视力。
英国医学研究理事会（MR/J004189/1 号拨款）、Ulverscroft 基金会、国家眼科研究中心、英国眼球震颤网络。
