Monitoring of the neurocritical in the perioperatory is in constant evolution. There are essentially two ultrasonographic application of neuromonitoring: the diameter of the sheath of the optic nerve and transcranial Doppler. Ultrasound-guided neuromonitoring can detect stenosis or occlusion of intracranial arteries, monitor the evolution of patients with vasospasm after subarachnoid hemorrhage, detect cerebral embolism, evaluate the cerebral collateral system, determine brain death, calculate indirectly Intracranial pressure and cerebral perfusion and helps in clinical decisions and early therapeutic interventions in neurocritical care. The purpose of this review is to present the applications of ultrasonography to the head of the patient in neuromonitoring.