Intracranial Pressure ( ICP ) monitoring is an essential component of traumatic brain injured ( TBI ) patients management. The clinical signs of raised ICP may be unreliable and may reflect relatively late cerebral decompensation. ICP may be monitored by invasive or non invasive techniques. While invasive techniques show the real time values of ICP, they are associated with many complications like, intracranial bleeding and infection, occlusion of the catheter tip by blood, debris and difficult to locate ventricle in presence of cerebral oedema. All these drawbacks of invasive methods can be averted by employing non invasive techniques of ICP monitoring. Although they do not show a real time value but are excellent tools to detect presence or absence of raised ICP. Elevated ICP can be detected by Computarised tomographic scan (CT) or Magnetic resonance imaging (MRI) but , these techniques are time consuming and require transportation of a patients who may be unstable .The quick and non invasive nature of ultrasonography is fast becoming popular for rapid detection of elevated ICP at bedside in emergency and ICU by monitoring the optic nerve sheath diameter ( ONSD ). Its limitations notwithstanding, ultrasonographic ONSD monitoring is likely to be more reliable than clinical assessment in the diagnosis of intracranial hypertension especially, when patient is under sedation which precludes proper clinical examination. Therefore, in recent years ,among non invasive methods, bedside ocular ultrasonography to monitor ICP has gained popularity.