Ocular Flutter in Parainfectious Meningoencephalitis: A Case Report

Ocular flutter is a rare, horizontal eye movement disorder characterized by intermittent bursts of conjugate horizontal saccades without intersaccadic intervals. It can occur in various clinical conditions such as metabolic dysfunction, infection and paraneoplastic syndrome. Herein, a 50-year-old male showed ocular flutter in parainfectious meningoencephalitis and immunoglobulin therapy led to an improvement of symptoms. This case can improve the understanding of the pathological mechanisms of ocular flutter.

Ocular Flutter in Hyperosmolar Hyperglycemic State during Treatment of Malignant Cerebral Edema

Ocular flutter (OF) is a rare eye movement disorder with horizontal saccadic oscillations without inter-saccadic intervals. The OF can occur in various clinical settings. A 83-year-old female showed the OF in hyperosmolar hyperglycemic state (HHS) following malignant cerebral infarction. The pathophysiology of the OF is still unclear, but this case provides a new information that the OF can occur in the context of toxic-metabolic state such as HHS.

Ocular flutter in acute doxylamine intoxication

Ocular flutter consists of bursts of high-frequency, low-amplitude, conjugate saccadic oscillations without normal intersaccadic interval and confined to the horizontal plane. Ocular flutter can be present during sleep, eyelid closure, attempted fixation, and volitional eye movements. Cerebellar fastigial nuclei disinhibition and/or inhibition of pontine omnipause cells disturb the excitatory/inhibitory balance of brainstem saccadic burst neurons, ultimately leading to saccadic oscillations including ocular flutter.1 The most common causes of ocular flutter in adults are paraneoplastic and parainfectious. Toxic metabolic etiologies are rare and include medications such as phenytoin and venlafaxine. Cerebellar and brainstem lesions have been reported, but the etiology remains unknown in approximately half of these patients.1,2 We present a case of ocular flutter in the setting of acute doxylamine intoxication. Doxylamine is a first-generation antihistamine widely available over the counter (OTC) as a sedative sleep aid, often combined with antitussives and decongestants.