A 40-year-old woman presented to our emergency department complaining of left hemiparesis and headache. She was awake and oriented, and her vitals were unremarkable except for a blood pressure of 180/100 without a history of hypertension. Past history and medications were negative. No trauma was reported. The optic nerve sheath diameter (ONSD) was measured and showed increased diameter of 0.47 cm bilaterally, demonstrating increased intracranial pressure (see Figure 1). Her level of consciousness decreased dramatically within 30 minutes, and she developed a right-sided gaze. She was intubated and underwent a brain CT showing intracranial hemorrhage in the right basal ganglia with midline shift and intraventricular hemorrhage (see Figure 2). She received a phenytoin loading dose and was taken emergently to the operating room. Fortunately, she survived with an acceptable neurologic outcome.
ONSD can predict increased intracranial pressure effectively. The exact measurement can be achieved by frequent practice. Thus, this approach is being described as an operator-dependent procedure.