~1% to 2% of all epilepsies; 22.5% among focal epilepsies in community studies; second, after temporal lobe epilepsy (TLE) in neurosurgical series.

Age at onset
Any age.

Males = females.

Neurological and mental state
Depends on etiology.

Symptomatic, cryptogenic, and idiopathic. In neurosurgical series, 2/3 of patients are symptomatic from malformations of cortical development (57.4%), tumors (16.4%), traumatic and other lesions (26.2%). Autosomal dominant nocturnal frontal lobe epilepsy is genetic.

Clinical manifestations
Motor manifestations are most common and most characteristic ictal symptom (90%). Frontal lobe seizures: (1) manifest with prominent motor manifestations (tonic, clonic, or postural); show frequent complex gestural automatisms at onset; (2) last usually for several sec; (3) progress to rapid secondary generalization (more common than in TLE); (4) show no or minimal post-ictal confusion; and (5) are frequent (several times a day and mainly during sleep).

See types of frontal lobe seizures according to main localization.

Diagnostic procedures
MRI often determines structural causes in ~60%. Functional neuroimaging is important for localization.

Inter-ictal EEG
Often normal; if abnormal, there may be background asymmetry, frontal spikes, or sharp waves (either unilateral or frequently bilateral or unilateral multilobar).

Ictal EEG
Usually normal. Ictal patterns consist of (1) frontal or multilobar, often bilateral, low-amplitude fast activity, mixed spikes, rhythmic spikes, rhythmic spike waves, or rhythmic slow waves or (2) bilateral high-amplitude single sharp waves followed by diffuse flattening. Uncommonly, the EEG abnormality precedes the seizure onset, providing important localizing information.

Usually unfavorable with regard to seizure frequency and response to drug treatment.

Differential diagnosis
Hypermotor seizures are frequently misdiagnosed as psychogenic movement disorders, familial paroxysmal dystonic choreoathetosis, paroxysmal kinesigenic choreoathetosis, or episodic ataxia.

Symptomatic frontal lobe absences may have similar clinical and EEG features of some typical absence seizures.

Management options
Drug treatment is the same as that for focal epilepsies. Seizures are usually resistant to AEDs. Their use is usually to protect the patients for secondarily generalized tonic-clonic seizures (GTCS).

Neurosurgery has limited success.

This page was adapted from:

The educational kit on epilepsies: The epileptic syndromes By C. P. Panayiotopoulos Originally published by MEDICINAE 21 Cave Street, Oxford OX4 1BA
First published 2006 and reprinted in 2007

Authored By: 
C. P. Panayiotopoulos MD, PhD, FRCP
Authored Date: 
Reviewed By: 
Steven C. Schachter MD
Sunday, June 1, 2008