Bedside ultrasound of the optic nerve sheath accurately predicted elevated intracranial pressure after head injury, according to a study published in Annals of Emergency Medicine. Researchers reported that the use of ultrasound accurately identified all eight (out of 59) adult patients who had CT findings of elevated intracranial pressure for a sensitivity of 100 percent. In comparison, clinical assessment by treating physicians identified only two of the patients with elevated intracranial pressure. Both optic nerve sheath diameter and clinical assessment has similar levels of false-positive results. The researchers emphasized that this use of ultrasound is still investigational.