*2.9.5 Multicontrast frameworks*

The sensitivity to detect lesions undetectable by conventional MRI has been shown to increase proportionally to the number of techniques employed, suggesting that each contrast interrogates specific aspects of tissue structure. The combined sensitivity of various contrasts can be assessed by multivariate framework [69]. This can be used in subtyping of FCD. This method showed that FCD type IIB was characterized by abnormal morphology, intensity, diffusivity, and function across all surfaces, while type IIA lesions presented only with increased FLAIR signal and reduced diffusion anisotropy close to the gray-white interface. This multimodal MRI profiling method shows that normalappearing cortex surrounding the lesion presents with alterations resembling those found at the lesion center [100]. This may help inform proper estimation of lesion extent.
