الفهرس 
Traumatic Brain InjuryOnly 14 pages are availabe for public view
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Abstract
Traumatic brain injury (TBI) is defined as brain damage resulting from external mechanical force leading to physical, cognitive, emotional and behavioral symptoms and outcome can range from complete recovery to permanent disability or death. TBI is a major cause of morbidity and mortality worldwide, mainly in children and young adults (1). Increased intracranial pressure (ICP), defined as sustained pressure greater than 20 mm Hg, is associated with poor clinical outcomes in patients with neurologic injury (2). Raised intracranial pressure (ICP) can cause secondary ischemic injury by decreasing cerebral blood flow, which would result in lessened cerebral oxygen delivery (3, 4). Measurement of ICP requires placement of an invasive monitor by a neurosurgeon, which may not be available in all hospitals. Brain CT are traditionally used for indirectly detecting raised ICP such as the presence of a midline shift of 5 mm and basal cistern and sulcal effacement. None of these methods is considered reliable in predicting raised ICP (5, 6). Measurement of optic nerve-sheath diameter (ONSD) on ocular ultrasonography (US) is considered as an indirect measurement of raised ICP and demonstrate it to be a reliable and useful tool (7). Because the optic nerve sheath connects to the dura mater that surrounds the brain and cerebrospinal fluid (CSF), a fluid-filled cavity is present between the optic nerve and the optic nerve sheath. Raised ICP will tend to inflate the sheath, leading to increasesin the ONSD (8).