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[Is benign childhood paroxysmal eye deviation a non-epileptic disorder?]
M Merino-Andreu1, J Arcas, E Izal- Linares
1Servicio de Neurofisiología Clínica, Hospital Universitario La Paz, Madrid, Spain. amartinez.hulp@salud.madrid.org
Insights
Benign childhood paroxysmal eye deviation (BCPED) can present with epileptic anomalies during sleep. Nocturnal polysomnography is crucial for diagnosis, though BCPED has a favorable prognosis.
Area of Science:
- Neurology
- Pediatrics
- Sleep Medicine
Background:
- Benign childhood paroxysmal eye deviation (BCPED) is conventionally classified as a non-epileptic paroxysmal disorder.
- Distinguishing BCPED from other paroxysmal disorders in children is clinically significant.
Observation:
- Four pediatric patients (6 months–2 years) experienced brief, recurrent upward conjugate gaze deviation episodes, exacerbated by fatigue.
- Standard neurological exams, imaging, and awake EEG-video monitoring were normal.
- Nocturnal polysomnography revealed focal or generalized paroxysmal discharges during non-REM sleep.
Findings:
- Nocturnal polysomnography identified epileptic anomalies in patients with BCPED, contradicting previous diagnostic assumptions.
- Sleep analysis showed shortened REM sleep latency, though its clinical significance remains unclear.
Implications:
- Nocturnal polysomnography is essential for diagnosing BCPED, revealing underlying epileptic activity.
- BCPED should be reclassified as a 'benign idiopathic epilepsy of childhood' due to its favorable prognosis.
- This reclassification impacts diagnostic approaches and treatment considerations for childhood paroxysmal disorders.
Introduction:
Benign childhood paroxysmal eye deviation (BCPED) is classified as a 'non-epileptic paroxysmal disorder'.
Case Reports:
We report the cases of four patients aged between 6 months and 2 years, who suffered brief episodes of upward conjugate gaze deviation, with no clonic movements or associated cognitive deterioration. These episodes, which lasted several seconds, appeared in short repeated bouts that became worse with fatigue. Results of the neurological exploration, laboratory examinations, neuroimaging (CAT, MRI, brain ultrasonography) and a neurophysiological study, which included EEG-video monitoring and EEG performed during the waking state, were all normal. A nocturnal polysomnographic study was later conducted for 7-8 hours and EEG, EMG and EOG readings were recorded. The trace showed focal or generalised paroxysmal discharges during non-REM sleep in the form of polyspike-wave and spike-wave complexes. Sleep analysis (Reschstaffen and Kales) showed only a shortened REM sleep latency, with no clear clinical meaning. Several cases have been reported in the literature with identical symptoms and normal results in the diagnostic tests, including daytime polysomnography.
Conclusions:
The appearance of these epileptic anomalies in the nocturnal study makes it necessary to perform a complete nocturnal polysomnography. In spite of these findings, BCPED courses favourably and has a benign prognosis both with and without antiepileptic treatment. We therefore believe that BCPED should be classed within the group of 'benign idiopathic epilepsies of childhood'.
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