ObjectiveWe report a special case to explain seizure semiology and epileptogenic network of seizure arising from ventral motor cortex, and to explore Focal cortical dycplasia (FCD) features on MR of epileptic patients with DEPDC5 mutation.MethodsA drug-resistant focal epilepsy patient with DEPDC5 mutation was underwent a detailed presurgical evaluation. The epileptogenic area(EA) was localized with SEEG and removed later by surgery. Related literatures were thoroughly reviewed.ResultsSubtle FCD of ventral branch of inferior precentral sulcus(IPv) on MR(1.5T) was noticed. With SEEG recording, seizure onset zone was detected on IPv with the probable lesion, early spreading to anterior insula, central operculum and ventral precentral gyrus. According to the architectures of ventral motor trend, seizure semiology with evolution from contralateral dystonia to ipsilateral chorea movement could be better comprehended. Seizure was controlled after totally resection on the sites of IPv, anterior insula, and central operculum. Pathological change was FCD type I. Other literatures reported that DEPDC5 mutation related FCD may be located in motor system, and seizure onset could also be in anterior insula cortex besides motor cortex in other SEEG cases.ConclusionsEarly contralateral dystonia and chorea movement could be definite figures of seizure arising from inferior precentral sulcus; DEPDC5 mutation maybe a clue to find subtle FCD in motor cortex.