A method for determining an anatomical landmark of a brain includes determining a first region in image data of the brain by segmenting the image data, aligning slices of the image data based on the first region, determining a skeletonized line in the determined first region, and extracting a mid-sagittal plane based upon a sagittal plane formed by the plurality of skeleton lines in the plurality of slices.The anatomical landmarks can be used to determine anatomical targets of a patient.