CT scan--the fundamental modality of investigation in head injury.
D001930:Brain Injuries / Q000000981:diagnostic imaging*; D006407:Hematoma, Epidural, Cranial / Q000000981:diagnostic imaging; D006408:Hematoma, Subdural / Q000000981:diagnostic imaging; D006801:Humans; D013353:Subdural Effusion / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed