Ultrasound is used in pediatric patients and in cirrhosis with portal hypertension.  It is fast and can be done without sedating.
Encephalopathy echocardiography or ultrasound
Epilepsy echocardiography or ultrasound
Cerebral venous sinus thrombosis physical examination
Bacterial meningitis physical examination
Encephalopathy other diagnostic studies
Brain abscess physical examination
Viral encephalitis physical examination
Epilepsy other diagnostic studies