Traumatic Brain Injury (IMAGE) Radiological Society of North America Caption A, gradient-recalled-echo (GRE), B, susceptibility-weighted imaging (SWI), and, C, quantitative susceptibility mapping (QSM) images in a patient with traumatic brain injury. The arrows indicate a cerebral microhemorrhage (CMH) that is visible on SWI, GRE, and QSM images. The arrowheads indicate another CMH that is visible on SWI and QSM images, but not the GRE image. ppb = parts per billion. Credit Radiological Society of North Aurora Usage Restrictions May use with credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.