[Opsoclonus and ocular flutter]

Ocular flutter is an ocular motor disorder consisting of involuntary back-to-back saccades in the horizontal plane without a saccadic interval. In opsoclonus, these pathological eye movements occur not only in the horizontal but also in the vertical plane. Originally, opsoclonus was described as irregular, conjugate, chaotic and partially continuous rapid eye movements. In this review, the clinical picture, differential diagnosis, etiology, natural course and therapeutic concepts for these eye movement disorders are described. It is stressed that continuous and intermittent forms of opsoclonus can be distinguished and that these differences usually correlate with the severity of the underlying disease. In contrast, the intermittent forms of opsoclonus and ocular flutter are usually only distinguished by the lack of a vertical eye movement component in ocular flutter.