Lingual epilepsia partialis continua: a detailed video‐EEG and neuroimaging study

Abstract

Motor epilepsia partialis continua (EPC) is a frequent and widely described variant of simple focal motor status epilepticus. However, lingual EPC is an unusual epileptic condition. We present a case of lingual EPC secondary to low‐grade glioma in which the EEG and neuroimaging features were particularly remarkable. The video‐EEG showed lateralized periodic discharges with superimposed rhythmic activity and frequent recurrent focal epileptic seizures. Moreover, brain magnetic resonance imaging showed a right temporo‐insular cortico‐subcortical lesion which was hyperintense on FLAIR, suggestive of low‐grade glioma. In addition, diffusion‐weighted imaging and arterial spin labelling series showed restricted diffusion in the right temporo‐insular and parietal cortex and increased cerebral flow, respectively. All these findings are in keeping with changes related to persistent focal status epilepticus. Finally, we review the literature and discuss the differential diagnosis of this rare epileptic entity. [Published with video sequence].

Lingual and Facial Myoclonus Associated with Early Corticobasal Syndrome

“…Lingual myoclonus is itself a very rare phenomenon, to date described sporadically as either a primary essential phenomenon, often rhythmic, 8 , 9 or as a secondary phenomenon, including various cortical and subcortical causes. 10 , 11 , 12 The lack of response to antiseizure medications in our case is noteworthy, as previously reported cases of lingual myoclonus of other etiologies have responded at least in part to, for example, clonazepam, 8 , 12 valproate, 9 lacosamide, levetiracetam, phenytoin, 10 and topiramate. 11 …”

First description of lingual focal motor status epilepticus due to acute ischemic stroke

“…Lingual SE reflects an underlying epileptic activity involving the cortical area of tongue representation in the contralateral primary motor cortex (epileptogenic zone) 9 . In this condition, clonic movements are usually not associated with a clear ictal pattern in the EEG: in most reports, the ictal EEG recordings are normal or only show muscle artifacts; in other reports lateralized (periodic) discharges can be seen 9 . We can only speculate about the reasons why an epileptogenic zone involving the tongue area does not correlate with EEG alterations.…”

“…9 In this condition, clonic movements are usually not associated with a clear ictal pattern in the EEG: in most reports, the ictal EEG recordings are normal or only show muscle artifacts; in other reports lateralized (periodic) discharges can be seen. 9 We can only speculate about the reasons why an epileptogenic zone involving the tongue area does not correlate with EEG alterations. Although the tongue area is located rather superficially within the primary motor cortex, unlike the hand area, it does not lie below the central electrodes C3/C4, but they are close to the temporal T3/T4 electrodes, which-however-are prone to recording muscle artifacts (even those originating from the tongue movements themselves) that could mask an undergoing ictal activity.…”