MRI Diagnosis of Focal Cortical Dysplasia

Objective To discuss the MR findings of focal cortical dysplasia(FCD).Materials and Methods MR findings of 23 patients with FCD confirmed by operation and histopathology were reviewed retrospectively.Sagittal,axial and tilted coronal(perpendicular to the long axis of hippocampus)scan.T1-weighted,T2-weighted and fluid attenuated inversion recovery(FLAIR)images were obtained.Results All lesions were local and localized in unilateral hemisphere.MR images showed thick cortices in 18 patients,blurring of the gray/white matter junction in 20 patients,abnormal signal intensity in the subcortical white matter in 22 patients,broad gyri and abnormal sulci in 14 patients,focal enlargement of the overlying subarachnoid space in 4 patients.T1-weighted,T2-weighted and FLAIR images showed blurring of the gray/white matter junction in 6,20 and 18 patients,abnormal signal intensity in the subcortical white matter in 3,16 and 19 patients,abnormal gyral/sulcal patterns in 12,10 and 11 patients respectively.Conclusion MR imaging abnormalities such as increased cortical thickness,blurring of the grey/white matter junction,hyperintensity signal in subcortical white matter on FLAIR and T2-weighted images and abnormal gyral/sulcal patterns,which suggest the presence of FCD.T2-weighted and FLAIR images are superior to T1-weighted images for detection interface of the grey/white matter,abnormal signal in the subcortical white matter.T1-weighted images are suitable for delineating abnormal gyral/sulcal patterns.