['To investigate the factors which influence the persistence of interictal epileptiform discharges (IED) after epilepsy surgery.', 'In this retrospective study we included patients with intractable medial temporal lobe epilepsy (MTLE) who underwent presurgical evaluation including high-resolution MRI and video-EEG monitoring with seizure registration prior to an anterior temporal lobe resection. The postsurgical outcome was assessed by our team 6 months and 2 years after the surgery.', 'One hundred and forty-seven patients fulfilled the inclusion criteria. The mean age of the patients was 31.8 (range 16-59 years). In 22 patients (15%) interictal epileptiform discharges were present on the postoperative routine EEG. We found that both the preoperative spike frequency ( P < 0.001 ) and postoperative seizures ( P = 0.04 ) were independently associated with the presence of IED on the postoperative routine EEG. The preoperative spike frequency was not associated with the postoperative outcome. The extent of resection showed no influence on the presence of postoperative IED.'] Are spikes on the postoperative EEG related to preoperative spike frequency and postoperative seizures?