Clinical and electrophysiological characteristics of startle epilepsy in childhood.

OBJECTIVE

Startle epilepsy is one syndrome of reflex epilepsies. We studied its clinical and EEG characteristics.

METHODS

Analysis of the clinical and EEG characteristics of startle epilepsy.

RESULTS

Of 11 patients, five were female. Age of onset ranged from 5 months to 7.5 years. Abnormal etiologies were found in seven patients, as a result of perinatal and postnatal factors. Neuroimaging showed abnormalities, commonly focal atrophy, in nine patients. Spontaneous seizures preceded or followed the startle seizures and were present in all patients. Startle seizures experienced included tonic, myoclonic, tonic-myoclonic, tonic-atypical absence, asymmetric tonic motor seizure and tonic-clonic seizure. Diffuse electrodecremental pattern was the most common ictal EEG pattern seen. The triggering stimuli of the startle seizures were sound in seven patients, touch in three and both sound and touch in one. Interictal EEG revealed abnormalities in 10 patients including generalized, multifocal or focal discharges. Many different anti-epileptic drugs were often unsatisfactory.

CONCLUSION

Startle epilepsies were often symptomatic reflex epilepsies and there were several types of startle seizure. The ictal EEG often showed a diffuse electrodecremental pattern. This disease has a bad prognosis.

SIGNIFICANCE

We delineated the clinical and EEG characteristics of startle epilepsy in childhood.