3D Brain Midline Delineation for Hematoma Patients

Brain midline delineates the boundary between the two cerebral hemispheres of the human brain, which plays a significant role in guiding intracranial hemorrhage surgery. Large midline shift caused by hematomas remains an inherent challenge for delineation. However, most previous methods only handle normal brains and delineate the brain midline on 2D CT images. In this study, we propose a novel hemisphere-segmented framework (HSF) for generating smooth 3D brain midline especially when large hematoma shifts the midline. Our work has four highlights. First, we propose to formulate the brain midline delineation as a 3D hemisphere segmentation task, which recognizes the midline location via enriched anatomical features. Second, we employ a distance-weighted map for midline aware loss. Third, we introduce rectificative learning for the model to handle various head poses. Finally, considering the complexity of hematomas distribution in human brain, we build a classification model to automatically identify the situation when hematoma breaks into brain ventricles and formulate a midline correction strategy to locally adjust the midline according to the location and boundary of hematomas. To our best knowledge, it is the first study focusing on delineating the brain midline on 3D CT images of hematoma patients and handling the situation of ventricle break-in. Through extensive validations on a large in-house dataset, our method outperforms state-of-the-art methods in various evaluation metrics.