Measurement of Optic Nerve Sheath in Traumatic Raised Intracranial Pressure

Trauma patients are at risk for serious head trauma. The consequences of serious head trauma are often life altering. Currently, the only method available to rapidly assess the severity of head injury and need for neurosurgical intervention is the CT scan. This time consuming test requires transportation of a potentially unstable patient to the CT scanner.

The investigators goal in traumatic brain injury is to identify early those patients who may require neurosurgical intervention. Brain swelling (elevated intracranial pressure) is transmitted to the eye and this can be measured with ultrasound. The investigators hypothesis is that this test will rule out significant elevations in intracranial pressure and perform as well as CT scan in doing this.

The investigators study aims to demonstrate that ultrasound of the optic nerve is as good as CT scan in ruling out clinically significant elevations in pressure within the brain. After consent has been obtained, any trauma patient who has an indication to undergo CT scan of the brain will also undergo ultrasound of the eye. A radiologist will then review the CT scans to determine if signs of elevated intracranial pressure are present. The investigators hope to demonstrate that a bedside ultrasound performed in the trauma suite is reliable for ruling out the possibility of elevated intracranial pressure.

**Update August 2009** Currently, deferred consent has been obtained from our REB allowing us to defer consent for this intervention of minimal risk. As well, REB has also approved phone consent in the interim.