temporal lobe spikes on EEG

 Neurologist says that she did not see seizures on the 24 hr. EEG. but thought she saw them on a regular EEG.  Is it possible to miss seeing seizure activity on a 24 hr. EEG, but show one on a reg. EEG, (Possible Petite Mals. I don't know the other term for these type of seizures.)