LGI: Cortical Shape-Adaptive Local Gyrification Index

[Software]

The amount of cortical folding, or gyrification, is typically measured within local cortical regions covered by an equidistant geodesic or nearest neighborhood-ring kernel. However, without careful design, such a kernel can easily cover multiple sulcal and gyral regions that may not be functionally related, resulting in the smoothing out of details of cortical folding and blurring local gyrification measurements. We propose a novel kernel shape for locally quantifying cortical gyrification within sulcal and gyral regions. We adapt wavefront propagation to generate a spatially varying kernel shape that encodes cortical folding patterns, including neighboring gyral crowns, sulcal fundi, and sulcal banks. To achieve this, we perform anisotropic wavefront propagation that runs quickly along gyral crowns and sulcal fundi by solving a static Hamilton–Jacobi partial differential equation. The resulting kernel adaptively elongates along gyral crowns and sulcal fundi, while maintaining a uniform shape over flat regions such as sulcal banks. We then measure local gyrification within the proposed spatially varying kernel. 

• Lyu, I., Kim, S., Girault, J., Gilmore, J., Styner, M., A Cortical Shape-Adaptive Approach to Local Gyrification Index. Medical Image Analysis, 48, 244-258, 2018 [link]

• Lyu, I., Kim, S., Bullins, J., Gilmore, J., Styner, M., Novel Local Shape-Adaptive Gyrification Index with Application to Brain Development. Medical Image Computing and Computer Assisted Intervention (MICCAI) 2017, LNCS10433, 31-39, 2017 [link]

Applications: Brain Disorder/Disease Studies

• Stoebner, Z., Hett, K., Lyu, I., Johnson, H., Paulsen, J., Long, J., Oguz, I., Comprehensive shape analysis of the cortex in Huntington's disease. Human Brain Mapping, 44(4), 1417-1431, 2023 [link]

• Zoltowski, A., Lyu, I., Failla, M., Mash, L., Dunham, K., Feldman, J., Woynaroski, T., Wallace, M., Barquero, L., Nyugen, T., Cutting, L., Kang, H., Landman, B., Cascio, C., Cortical morphology in ASD: findings from a cortical shape-adaptive approach to gyrification indexing. Cerebral Cortex, 31(11), 5188-5205, 2021 [link]