The Spectrum of Ocular Neutomyotonia / 国际眼科杂志(Guoji Yanke Zazhi)

ABSTRACT

Objective To probe into the causes, clinical features, diagnosis and treatment of ocular neuromyotonia (ONM). Methods To deeply analyze and discuss the causes, clinical features, diagnosis an treatment of this disease by reporting 4 cases of ONM and refor a pituitary tumor. The spasms occurred in the primary position of gaze and were induced by eccentric gaze. A 72 year-old man had chronic arachnoiditis after myelography with radioactive thorium dioxide many years ago. Spasms of muscles innervated by a third nerve and a sixth nerve were produced by eccentric gaze. Treatment with carbamazepine stopped the ONM in both patients. A 47 year-old man had ONM of a lateral rectus muscle when he looked in eccentric gaze several years after irradiation for a cerebellar medulloblastoma. The spasms occurred when treatment for seizures with carbamazepine was decreased, and resolved with the dosage was increased.A 21 year-old man had recurrence of a congenital hemangioma of the neck, face and brain that caused ONM of a superior oblique muscle many years after it had been partially excised. Downward gaze cau sed the spasms, and they resolved spontaneously. Conclusion ONM begins months to years following treatment for intracranial lesions. Typically, the treatment is radiation for an intracranial tumor, but other eauses of damage to the cranial nerves can produce the syndrome. Spasm of extraocular muscles innervated by the third, fourth or sixth cranial nerves produce strabismus and diplopia, lasting from a few seconds to a few minutes. The spasms are spontaneous or induced by ecceutric gaze that stimulates the affected cranial nerve. Neuroradiologic tests might show abnormalities in or near the cavernous sinus, but usually do not show recurrence of the original tumor. The syndrome rarely resolves spontaneously, but responds well to treatment with carbamazepine.