Epileptic nystagmus: A case report and systematic review

Abstract

PurposeWe aimed to define the characteristics of epileptic nystagmus and correlate those with other clinical findings in a large number of patients.MethodsWe report a patient with epileptic nystagmus and additionally reviewed the reported clinical features of 36 more patients through a systematic literature search. We analyzed the characteristics of epileptic nystagmus and attempted correlations of those with alertness of the patients and epileptic foci on EEG.ResultsAll 33 patients with unilateral horizontal nystagmus showed nystagmus beating away from the side of ictal discharges. Epileptic nystagmus was preceded by gaze deviation in 21 patients, with contraversive in 19 and ipsiversive in 2. Seizures associated with epileptic nystagmus were mostly focal (25/29, 86.2%) with or without loss of awareness. Ictal discharges originated from the occipital (n = 16), parietal (n = 9), temporo-occipital (n = 6), frontal (n = 4), and temporal (n = 3) areas, and two patients had multiple epileptic foci. Seizures were usually symptomatic (24/37, 64.9%). The presence of preceding gaze deviation and midline crossing of the nystagmus did not correlate with the ictal onset zone or alertness of the patients. Recording of epileptic nystagmus was available only in 6 patients, and the epileptic nystagmus could be localized to the saccadic areas in two and to the smooth pursuit areas in another two. Two patients showed the features of epileptic nystagmus from both areas.ConclusionEven though the localizing value of epileptic nystagmus seems limited in previous reports, the fast phase of epileptic nystagmus was almost always directed away from the epileptic focus that mostly arose from the posterior part of the cerebral hemisphere.

Conjugate Eye Deviation on CT Associated With Worse Outcomes Despite IV Thrombolysis

“…2 Conjugate eye deviation (CED) can localize to multiple areas including the medial frontal gyrus, the parapontine reticular formation, and other cortical areas involved in spatial neglect, [3][4][5] and may be associated with other acute neurological events such as seizure, postictal states, and systemic mimics of stroke such as hyperglycemia. [6][7][8] Ipsilateral CED on brain CT (CT-CED) has been associated with worse outcomes in patients with stroke 9 but has not been evaluated as a tool in identifying acute endovascular therapy candidates. The CED suggests cortical frontal lobe involvement in most cases and may indicate large vessel occlusion.…”

Ipsiversive ictal eye deviation in inferioposterior temporal lobe epilepsy—Two SEEG cases report

“…Epileptic eye deviation in seizure originated from the parieto-temporo-occipital region had been reported previously [ 8 – 16 ]. The underlying mechanisms of lateralized eye deviation during epileptic stimulation had been presumed as below: contralateral eye deviation is attributed to the involvement of cortical saccadic areas, and the stimulation of smooth pursuit cortical areas during epileptic seizures causesipsilateral ocular deviation [ 8 , 9 , 14 , 33 ]. However, actual case of epileptic ipsiversion, manifesting as eyes conjugate deviation to the ipsilateral side of the epileptic focus, was rarely reported [ 33 ], and empirical evidence on the presumed mechanisms underlying the ipsilateral eye deviation has not been documented in details.…”

Okzipital- und Parietallappenepilepsien – Klinische Anfallssemiologie und Elektrophysiologie

“…Allerdings ist die Verlässlichkeit der Lateralisation des Nystagmus unklar, da auch ipsiversive okuloklonische Muster beschrieben wurden. Der Anfallsbeginn wird in den rostralen Teilen des Okzipitallappens (Brodmann-Areal 19) angenommen, aber auch im Brodmann-Areal 7 des Parietallap-pens können diese Anfälle generiert werden [16,21].…”