Bova S M, Giovenzana A, Signorini S, La Piana R, Uggetti C, Bianchi P E, Fazzi E
Centre of Child Neuro-Ophthalmology, Department of Child Neurology and Psychiatry, University of Pavia, Italy.
Dev Med Child Neurol. 2008 Apr;50(4):311-5. doi: 10.1111/j.1469-8749.2008.02044.x. Epub 2008 Feb 28.
Plasticity of visual systems after early brain damage has been extensively studied in animal models but poorly documented in children after visual pathway lesions. This report describes the visual recovery of a male child who had a bilateral occipital lobe infarction at the age of 2 years 6 months, 10 days after colon resection for Hirschsprung disease. In the acute phase he had severe visual impairment without visual response. Some weeks later he could perceive movement. Since then, progressive recovery of his visual acuity and oculomotor abilities has been accompanied by a progressive reduction of the visual field defect. At 6 years 8 months, visual recognition acuity was 10/10 in both eyes and neuro-ophthalmological examination was normal, except for persistence of the visual field defect in the upper hemifield and a selective impairment of higher visual functions (recognition of object presented in a hard-to-decode way [e.g. overlapping figures], or use of complex visuospatial skills). The functional recovery observed in this patient confirms the adaptive plasticity of developing visual systems after early brain lesions. It suggests that in humans, as in animal models, processes related to cerebral plasticity may take place years after a brain lesion has been sustained.
早期脑损伤后视觉系统的可塑性在动物模型中已得到广泛研究，但在视觉通路受损的儿童中记录较少。本报告描述了一名男童的视觉恢复情况，该男童在2岁6个月时因先天性巨结肠症接受结肠切除术后10天发生双侧枕叶梗死。急性期时，他有严重的视力障碍且无视觉反应。几周后，他能感知运动。从那时起，他的视力和动眼能力逐渐恢复，同时视野缺损也逐渐减轻。在6岁8个月时，双眼的视觉识别视力均为10/10，除了上半视野的视野缺损持续存在以及较高视觉功能（识别以难以解码方式呈现的物体[如重叠图形]或使用复杂视觉空间技能）存在选择性损害外，神经眼科检查正常。该患者观察到的功能恢复证实了早期脑损伤后发育中的视觉系统具有适应性可塑性。这表明在人类中，如同在动物模型中一样，与脑可塑性相关的过程可能在脑损伤发生数年之后才会出现。
