Neuro-ophthalmologic assessment and investigations in children and adults with cerebellar diseases.

In this chapter, we present the bedside assessment and laboratory tests that are available for the neuro-ophthalmologic evaluation of children and adults with cerebellar diseases. In the evaluation of a patient with cerebellar dysfunction, recognizing the pattern of ocular motor and / or vestibular impairment is often a key step to the correct diagnosis. The cerebellum is very important in processing a wide range of different eye movements, including angular vestibulo-ocular reflexes, otolith-ocular reflexes, fixation and gaze holding, smooth pursuit eye movements, saccadic eye movements, optokinetic response, ocular alignment, and vergence. Quantitative eye movement recording is now widely available in specialized clinics and medical practices, especially for testing the vestibulo-ocular reflexes. We describe the approach for assessing specific eye movements linked to cerebellar function, discuss appropriate eye movement laboratory tests, and summarize recent related research findings. In addition, for each laboratory test, we discuss its advantages, disadvantages, indications, and interpretations. Furthermore, we provide differential diagnoses for specific ocular motor and vestibular abnormalities such as slow saccades or impaired vestibulo-ocular reflexes.