Epilepsy, commonly known as “sheep epilepsy”, is a chronic disease in which sudden abnormal discharges of neurons in the brain cause transient brain dysfunction. The prevalence of epilepsy is about 7 per 1,000, and 3.5% of the general population has one convulsive seizure in their lifetime, but a convulsive seizure does not mean epilepsy. Epilepsy is a brain disorder with recurrent fixed seizures, and there are about 9 million epilepsy patients in China, of which about 2.7 million are refractory to treatment. 70% of epilepsy patients can obtain satisfactory results through antiepileptic drug treatment, but there are still about 30% of epilepsy patients who are refractory to drug treatment. Surgical treatment of epilepsy is an intervention aimed at improving or controlling seizures using surgical procedures for people with refractory epilepsy. In patients with refractory epilepsy, appropriate surgical treatment can not only reduce, decrease or even will completely control seizures, but to some extent improve the neuropsychological function of the patient. Let us first understand the two definitions of functional brain areas and refractory epilepsy. The functional areas of the brain, as the name implies, are the locations of the higher centers that are responsible for various functions of the body. For example, the first motor area in the precentral gyrus governs limb movements; the sensory center in the postcentral gyrus and the posterior half of the paracentral lobule governs somatic sensations such as temperature, pain, touch, pressure, and position and motion perception; the motor speech center in the posterior third of the inferior frontal gyrus governs speech, and so on. Refractory epilepsy: Patients with epilepsy that is difficult to control with regular drug therapy (at least 2 or more antiepileptic drugs that can reach effective blood levels) and with frequent seizures for a long period of time (an average of one seizure per month for ≥ l8 months). Case sharing Patient, male, 3 years old. The patient was admitted to the hospital with the main reason of recurrent convulsions for more than 3 years. The patient had recurrent convulsions with no obvious cause more than 3 years ago (5 months after birth), initially showing left-sided limb shaking, flushed face, and double gaze, which lasted about 1 minute and relieved during sleep, 3-4 times/day. “Three years ago (8 months after birth), she had another seizure, which was characterized by double gaze, flexion and straightening of the limbs, lasting about 1 minute and relieved by 5-6 seizures per day, and was given phenobarbital, carbamazepine and vitamin B6. “antiepileptic” and so on, the improvement is not obvious. In the past 4 months or so, the seizures were frequent, with 6-10 seizures per day. After admission, cranial MRI was performed: abnormal signal foci in the left radiocoronal area or left frontal subcortical white matter area with mild edema in the left middle frontal gyrus, possible gliosis or low-grade astrocytoma. eeg: mild abnormality in dynamic EEG (read the map to see spike waves in the left temporal dominant whole conduction). l course l EEG results showed: 1. interictal epileptiform discharges, cerebral regional (left central parietal and middle and posterior temporal regions); left central parietal and Central-posterior temporal region limited slow wave and activity sustained long-range discharges; 2. Seizure phase: aura – froze – right limb predominantly tonic – bilateral asymmetric tonic – right upper limb Todd palsy after seizure, EEG: left side predominant origin. High-frequency EEG showed: left central parietal and middle and posterior temporal predominantly sharp slow and sharp waves mixed in restricted slow activity repeatedly in long-range. PET/CT during the interictal period showed that the left frontal lobe was lamellar hypometabolic foci. The results indicated that the foci were located in the anatomical left posterior inferior frontal gyrus and the lower left precentral gyrus, and the motor area was located in the anatomical left posterior central gyrus. After 1 week, the left lesion and part of the epileptogenic foci were resected and the functional area where the epileptogenic foci were located was cauterized. EEG monitoring was performed intraoperatively, and a large number of epileptiform waves were basically disappeared after surgery. The postoperative pathology was diagnosed as cortical heterotopia. Postoperatively, the child recovered well with no significant functional impairment. The intensity and frequency of seizures were significantly better, and there were no grand mal seizures, only manifestations such as left hand tremor and left eye blinking, 0-2 times/day, each lasting only a few seconds. The child was followed up for 2 months without any significant aggravation. This child was diagnosed as having refractory epilepsy because it was difficult to control after regular treatment with two or more antiepileptic drugs and had frequent seizures for a long time, and because the epileptogenic lesion was located in the language and motor centers, it was diagnosed as functional refractory epilepsy. The functional epilepsy surgery is difficult because the epileptogenic lesions are located in the posterior part of the left inferior frontal gyrus and the lower part of the left precentral gyrus (the higher centers that govern human language and movement). Especially in children, it is more difficult because their brains are not yet developed and the preoperative examinations are not well coordinated. After our preoperative video EEG, EEG monitoring with subdural electrode implantation, functional area determination and imaging examination, the epileptogenic focus was finally accurately localized and successfully treated, with good postoperative results and no functional impairment.