Paroxysmal tonic upgaze accompanied by occipital discharge on electroencephalography: a case report and literature review

Abstract

Background Paroxysmal tonic upgaze (PTU) is an infantile-onset paroxysmal neurological disorder that is characterized by episodes of sustained conjugate upward eye deviation. The paroxysmal abnormal eye movements need to be differentiated from seizures. We report a case of PTU with occipital discharge on electroencephalography (EEG), which made the diagnosis more complicated. Case presentation A 6-month-old girl presented with paroxysmal upward deviation or left strabismus of the eyes, with a bowed head, lowered jaw, raised eyebrows, closed lips, and slight grin. Each episode lasted for a few seconds, and episodes occurred multiple times per day. EEG showed spike waves in the right occipital region, and the girl was initially misdiagnosed with epilepsy. After further analysis using video EEG, we corrected her diagnosis as PTU and stopped the administration of an antiepileptic drug. Conclusion PTU accompanied by discharge on EEG may lead to a misdiagnosis. Video EEG monitoring, and especially the analysis of EEG traces synchronized with attacks, can provide evidence to distinguish between seizures and non-epileptic events.