Automated Segmentation of Knee Cartilage from Ultra-High Resolution 7 Tesla 3D bSSFP MRI Using Transfer Learning

7T 3D knee MRI shows great promise for the quantification of cartilage volume and thickness to assess osteoarthritis, but manual segmentation is time consuming. Segmented 7T 3D knee datasets to train machine learning techniques are limited. Here, we trained a network on a larger dataset of segmented 3T 3D knee MRI scans and used transfer learning to create an automatic segmentation network of 7T MRI knee cartilage using a small number of segmented 7T images. The resulting network constructed demonstrated vastly improved automatic segmentation of the knee cartilage at 7T compared to the network trained with limited 7T data only.