[Motorocular syndromes due to neurogenic hyperactivity and their treatment]

In this chapter we describe a variety of rare but clinically identifiable ocular motor syndromes, including ocular neuromyotonia, superior oblique myokymia, ocular motor synkinesis, third nerve palsy with cyclic spasms, and paroxysmal manifestations of multiple sclerosis. These syndromes share many characteristics. They result from neurogenic hyperactivity, causing episodic spasms of one or several extraocular muscles. The pathophysiology is not fully understood, but it usually includes both a focal and partial lesion of one of the ocular motor nerves and a central rearrangement of neuronal activity in the ocular motor nuclei. Treatment with membrane-stabilizing agents, such as carbamazepine, is usually effective to reduce the symptoms. The above-mentioned syndromes result from a number of different diseases. A proportion of apparently idiopathic cases may be related to a neurovascular compression syndrome.