Ocular Neuromyotonia Associated with Chronic Inflammatory Demyelinating Polyneuropathy

Abstract

Ocular neuromyotonia (ONM) is a neuro-ophthalmic disorder characterized by episodic diplopia caused by contraction of one or more ocular muscles due to spontaneous excitation of the respective ocular motor nerve. We report a patient whose ocular neuromyotonia arose in the setting of a subacute demyelinating polyneuropathy consistent with chronic inflammatory demyelinating polyneuropathy (CIDP) and subsequently resolved following the initiation of intravenous immunoglobulin (IVIg) for her neuropathy. Our patient provides additional evidence towards the role of demyelination and ephaptic neurotransmission in ocular neuromyotonia and also represents the first reported case of ocular neuromyotonia associated with a systemic neurological condition.

Ocular neuromyotonia: a review of diagnosis and treatment

“…Other causes of ONM as reported in the literature include hypovitaminosis D [3], congenital [22], alcohol ingestion [23], Paget disease of bone [24], myelogram with thorium toxicity [25], cavernous sinus thrombosis secondary to mucormycosis [26], intramedullary stroke [27], chronic inflammatory demyelinating disease [28], botulinum toxin injection [29], brainstem demyelination [30], Tolosa–Hunt syndrome [31], idiopathic [32], intracranial tumor [33], and as a presenting sign of meningioma [34].…”

Ocular neuromyotonia caused by a recurrent sphenoidal ridge meningioma

“…Neuromyotonia is a condition of spontaneous and continuous muscle fiber activity of the peripheral nerve origin. [ 7 ] Ocular neuromyotonia (ONM) is a rare ocular motility disorder characterized by paroxysmal and involuntary extraocular muscle contractions,[ 1 ] occurring due to radiation therapy of the parasellar region,[ 11 ] inflammatory or autoimmune disease,[ 6 ] or nerve compression by the vascular structure. [ 2 , 3 , 5 , 9 , 12 , 13 ] However, no cases have been reported in which ONM occurred due to an intracranial tumor.…”