This dataset contains pre-operative MR and intra-operative ultrasound data from 23 patients with low-grade gliomas (brain tumors). The dataset also contains homologous landmarks for validation of image registration methods. The image data are available in NIFTI and MINC formats. DATASET GUIDE: The landmarks of the data are in MINC tag file format with the extension ".tag". The easiest way to visualize the MINC image pair with the homologous landmarks is to use the software 'register' that comes with MINC Toolkit (https://bic-mni.github.io). To view the images, please use the following command in your terminal: "register image1.mnc image2.mnc landmarks.tag" Each row of the landmarks with six data entries represents a landmark pair. In each row, the first 3 columns are the x-, y-, and z-coordinate of landmarks belonging to image1 in world coordinates (unit = mm), and the latter 3 columns are the x-, y-, and z-coordinate of landmarks belonging to image2 in world coordinates (unit = mm). The reference MRI volume is always put as image1. In the RESECT database, this is the ultrasound before resection. The world coordinates of the corresponding MINC and NIFTI files are the same. You can find more information on the dataset at: https://yimingxiao.weebly.com/data-repositories.html