At their core, human beings are visual beings, and this is evidenced by the fact that most of the human brain is devoted to the visual system. The visual sensory or afferent pathways not only include the retina, optic nerve, chiasm, optic tract, lateral geniculate nucleus, optic radiations, and primary visual cortex, but also the parietal and temporal lobes, which are involved in processing visual information to produce a rich and vibrant sensory experience. The motor or efferent visual system, which directs eye movement to optimize target-specific viewing of the object of interest and capture visual information, requires extraocular muscles, cranial nerves, and their nuclei, which are found in the midbrain, pons, and brainstem. However, they also require the supranuclear network found in the frontal eye fields, parietal lobe, supplementary eye fields, superior colliculus, basal ganglia, and reticular formation.
In human development, there is a dynamic interplay between the sensory and motor visual pathways, which depend on each other at critical periods to establish normal vision. Moreover, abnormalities in development and/or childhood-acquired dysfunction in either motor or sensory domains can ultimately disrupt development of both areas. Disorders of vision and ocular motility in pediatric patients can impede other areas of normal development and later affect a child’s independence, education, social interactions, and daily function.
In this chapter, we focus on disorders of subnormal vision and ocular dysmotility by reviewing pediatric neuro-ophthalmic history and examination. Furthermore, this chapter is intended to serve as a framework to approach the child with abnormal visual behavior and abnormal eye movements.
PEDIATRIC NEURO-OPHTHALMIC HISTORY
History in our complex neurologic patients can be quite time consuming. To expedite data collection during the interview, patients and their families are often requested to bring neuroimaging, prior ocular or neurologic exams, and any testing (eg, laboratory workup, ocular imaging) to the office visit.
History of Present Illness
History taking ought to be open-ended and general so as not to bias responses from the child or the parents. Below is a framework for organizing questions to cover the principal aspects of functional vision in a new pediatric patient:
Introductory questions: “Do you have any concerns about your child’s vision?” and “What do you think your child can and cannot see?” are some examples of introductory questions. The answers to these general questions can help direct the interview to focus on specific domains of vision and ocular motility.
Peripheral vision: Asking how the child navigates their environment can reveal localizable visual field deficits such as hemianopsias. Example questions include “How does your child get around the room or house?” and “Does your child bump into things?” It should be noted that unusual head movements or postures might not always implicate visual field defects but may rather suggest ocular motility disorders such as nystagmus or diplopia.
Central vision ...