Clinical characteristics analysis of focal cortical dysplasia with negative MRI

Objective To comparative analysis of clinical characteristics, pathological types, and prognosis of focal cortical dysplasia (FCD) with positive and negative MRI. Methods and Results A total of 96 patients with FCD who underwent epileptic foci resection surgery at Xuanwu Hospital, Capital Medical University from January 2015 to June 2021 were selected. According to the presence of abnormal imaging findings in preoperative FLAIR imaging, patients were divided into MRI positive group (n = 39) and MRI negative group (n = 57). The proportion of FCDⅡA in the MRI negative group was higher than that in the MRI positive group (χ2 = 8.370, P = 0.004); there was a statistically significant difference in the types of epileptic seizures between the 2 groups (Fisher's exact probability: P = 0.037). Among them, the MRI negative group had a higher proportion of complete loss of consciousness seizures (Fisher's exact probability: P = 0.036) and multiple types of seizures (Fisher's exact probability: P = 0.036) than the MRI positive group, with a higher proportion of patients with focal perceptual seizures. The MRI negative group had a higher proportion of complete loss of consciousness seizures (adjusted χ2 = 4.728, P = 0.030) and multiple types of seizures (adjusted χ2 = 4.728, P = 0.030) than the MRI positive group, with a higher proportion of patients with focal perceptual deficit seizures. The proportion of postoperative epileptic seizures in the MRI negative group was higher than that in the MRI positive group (χ2 = 9.013, P = 0.003). Conclusions The proportion of epileptic seizures in MRI negative FCD patients 2 years after surgery is higher than that in MRI positive FCD patients. The proportion of FCDⅡA in MRI negative FCD patients is higher than that in MRI positive FCD patients. MRI negative FCD patients mainly have complete loss of consciousness seizures and multiple types of seizures.