Ocular Neuromyotonia in Graves Dysthyroid Orbitopathy

Cyclic (alternate day) vertical deviation—possible forme fruste of ocular neuromyotonia

“…These closely resemble the episodic hypotropia caused by ocular neuromyotomia in Graves' disease described by Chung and colleagues. 24 Two of our cyclic cases in this series had thyroid eye disease.…”

Novel Case of Ocular Neuromyotonia Associated with Thyroid-Related Orbitopathy and Literature Review

“…16 The ONM that is associated with Grave orbitopathy, or thyroid-associated orbitopathy, is proposed to be compressive in nature, resulting from the inflammatory scarring and crowding of the ocular nerves and muscle cells. 19 Chung et al 19 hypothesize ''that massive inflammatory cell infiltration and mucopolysaccharide deposition into the interstitial spaces of the endomysium may cause neuronal irritability and axonal degeneration by direct compression of the neurons or by vascular compromise.'' This insult to the neuronal membrane may allow for cross talk between neurons or ephaptic transmission that is hypothesized to cause ONM.…”

Ocular Neuromyotonia Noted after Recent Botulinum Toxin Injection for Sixth Nerve Palsy Following Resection of a Posterior Fossa Skull Base Meningioma

“…1 Reported causes include prior radiation treatment, chronic cranial nerve palsy affecting ocular motility, thyroid-related orbitopathy, compressive lesions, or stroke. 2,3 There have even been a few reported cases that are idiopathic in origin. 3 The precise pathophysiology of the disorder is unknown, but is thought to be related to axonal instability.…”