A negative long-range video EEG does not rule out epilepsy, it only means that no epileptic discharges were detected at the time of the test. Long-range video EEG consists of an EEG monitoring system and a video recording system, which compensates for the low positive rate of regular EEG and allows simultaneous recording of images of the patient during a seizure and the EEG changes during the seizure. The typical testing time is 24 hours. Although long-range video EEG can improve the chances of detecting epileptic discharges during the test, it is true that some patients with epilepsy have consistently normal long-range video EEG in the clinic, so a negative long-range video EEG simply means that there are no epileptic waves present during the long range procedure. Although a negative long-range video EEG does not rule out epilepsy, the detection of epileptic discharges is significant in the diagnosis of epilepsy, and for this reason the EEG is considered to be the most important adjunctive test for epilepsy.