Childhood-onset epilepsy in patients with dyskinetic cerebral palsy caused by basal ganglia and thalamic lesions

Objective: To elucidate the incidence and outcomes of childhood-onset epilepsy and associated factors in term-born patients with basal ganglia and thalamic lesion (BGTL)-induced dyskinetic cerebral palsy (DCP) caused by perinatal hypoxic-ischemic encephalopathy (HIE).

Methods: We studied 104 term-born patients with BGTL-induced DCP (63 males and 41 females, aged 2-22 years) to investigate the incidence of epilepsy and the factors related to its development. We used multivariate analysis to assess perinatal factors, gross motor function, and the extent of brain lesions. We also investigated the seizure onset, clinical course, and electroencephalography (EEG) characteristics.

Results: The cumulative epilepsy incidence was 36%. Multiple logistic regression analysis revealed that deep white matter lesions were the only independent risk factor for epilepsy. The confirmed seizure types included epileptic spasms (ES, n = 13), myoclonic seizures (MS, n = 6), and focal-onset seizures (FS, n = 24). Only patients with deep white matter lesions exhibited ES or MS. The symptoms of FS resembled those of self-limited epilepsy with centrotemporal spikes; however, only half of the patients reached remission by the time of investigation, and four patients had more than one seizure per month despite appropriate drug therapy. Focal spikes in the peri-rolandic area were detected not only in patients with FS but also in half of the patients without epilepsy.

Conclusions: One-third of term-born patients with BGTL-induced DCP caused by perinatal HIE develop epilepsy, and deep white matter lesions increase the likelihood of epilepsy. Preparation for early-onset ES, MS, and subsequent FS is beneficial.