The reason to use an XML format in this challenge is that we use a well-established software[1]: CASCADE, to carry out the manual segmentation and label for carotid vessel wall images, in which the sub-pixel segmentation and smoothness of the segmentation boundaries were all well dealt with and recognized by the vessel wall imaging community. Therefore, we provide the vessel wall segmentation labels based on the format of CASCADE, which is in XML. We totally agree with you that this may be difficult to work with. To solve this problem, we provide the reference Python code https://drive.google.com/file/d/1DzWLq0mVWeoZ6f6vLXtSKN1h98T9GPUC/view?usp=sharing to illustrate how to load the XML files.