Clinical, Radiological, and Electroencephalographic Evaluation of Children with Headache: A Cross-Sectional Study.

OBJECTIVE: This study aimed to evaluate the clinical, electroencephalographic (EEG), and magnetic resonance imaging (MRI) findings of pediatric patients presenting with headache to a pediatric neurology outpatient clinic, and to determine the diagnostic utility of EEG and MRI across different headache subtypes. METHODS: A total of 751 children aged 2-18 years who presented with headache between 2013 and 2024 were analyzed. Demographic characteristics, seizure history, headache classification (ICHD-3), neurological examination findings, EEG results, and MRI findings were reviewed. Only patients who had undergone both EEG and brain MRI were included in the study. Statistical analyses used the Mann-Whitney U-test, chi-square test, and Fisher's exact test. RESULTS: A total of 751 patients (median age 12 years; 53.7% female) were included. Electroencephalographic and brain MRI were performed in all included patients (n=751). Primary headaches accounted for 632 patients (84.2%): tension-type headache 315 (41.9%), migraine 255 (34.0%), unclassified headache 59 (7.9%), and cluster headache 3 (0.4%). Seizure history was most frequent in the unclassified headache group (14/59, 23.7%), compared with 4/255 (1.6%) in the migraine group, 11/315 (3.5%) in the tension-type group, 0/3 (0%) in the cluster headache group (P < .001). Abnormal EEG findings were detected in 105 of 751 patients (14.0%). Among these, 74 patients (70.5%) had focal epileptiform activity, 25 (23.8%) had generalized epileptiform activity, and 6 (5.7%) exhibited abnormal background rhythm. Of the 105 patients with abnormal EEG findings, 35 (33.3%) had a clinical history of seizures. Abnormal EEG activity was most common in the unclassified headache group [25/59 (42.4%)], compared with migraine [23/255 (9.0%)] and tension-type headache [38/315 (12.1%)] (P < .001). Magnetic resonance imaging abnormalities were present in migraine [113/255 (44.3%)], tension-type headache [141/315 (44.8%)], unclassified headache [39/59 (66.1%)], and secondary headache [109/119 (91.6%)]. Magnetic resonance imaging was normal in (349/751, 46.5%) of cases, while the most common MRI abnormality/incidental finding was sinusitis and/or chronic mucosal thickening (171/751, 22.8%). CONCLUSION: Electroencephalographic and Magnetic resonance imaging are not routinely indicated for typical primary headaches but may be useful for patients with unclassified headaches, abnormal neurological findings, or suspected seizure-related symptoms. Unclassified headaches represent a heterogeneous group requiring closer follow-up and selective diagnostic evaluation. An overlap between headache and epilepsy may be particularly notable in certain subgroups.