The reversal sign on CT of hyper-acute diffuse traumatic brain swelling in an infant

Reiichi Ishikura, Kumiko Ando, Masayo Ogawa, Yoshihiro Takada, Shozo Hirota
Department of Radiology, Hyogo College of Medicine

Abstract
　　We present the case of a 6-month-old boy who underwent brain CT and MR imaging within 90 minutes after traumatic injury. CT image obtained within 1 hour of trauma showed the so-called reversal sign on CT, with reversal of the relatively greater density of the cerebellum compared to that of the cerebrum. The diffusion weighted images (DWI) of MRI obtained 90 minutes after onset showed pan-cerebral restricted diffusion, whereas T2-weighted and FLAIR image findings were normal. In our case, the image finding of the reversal sign on CT was equally diagnostic as DWI of MRI for diffuse traumatic brain swelling in the hyper-acute state.

Keywords： Reversal sign on CT, Diffusion weighted image on MRI, Infant, Traumatic diffuse brain swelling