ATYPICAL ABSENCE SEIZURE

An atypical absence seizure has less abrupt onset and offset of loss of awareness than typical absence seizures. They are often associated with other features such as loss of muscle tone of the head, trunk or limbs (often a gradual slump) and subtle myoclonic jerks. Atypical absence seizures often occur in individuals with intellectual impairment.The loss of awareness may be minimal with the patient continuing an activity, but more slowly or with mistakes.

CAUTION These seizures can be difficult to recognize in a patient with ongoing generalized slow (<2.5Hz) spike-wave on EEG, careful correlation between EEG and clinical state is recommended.