Traumatic brain injury (TBI) is defined as a structural injury to the brain or a disruption in the normal functioning of the brain as a result of a blunt or Penetrating head injury. Head injury refers to trauma to the head that may or may not be associated with TBI, soft tissue injury, or skull fractures. Primary brain injury occurs as an immediate consequence of head injury at the time of the trauma.Secondary Brain Injury is indirect and results from physiological changes triggered by the initial impact and/or acute management measures; it is preventable to a certain degree. TBI is most frequently seen in young children, teenagers, and individuals older than 65 years, with falls and Motor vehicle collisons being the leading causes. The Glasgow Coma Scale is a commonly used scoring system used to assess the severity of TBI and guide management. Clinical Features of TBI depend on the severity, type, and location of brain injury. Impaired consciousness is common in severe TBI whereas patients with mild TBI may only present with transient confusion and headache.Neuroprotective measures to prevent or minimize secondary brain injury should be the main focus of initial management of all patients with TBI. Patients with moderate TBI or severe TBI should be transferred to a neurocritical care unit at the earliest. After initial resuscitation, a head CT without contrast should be obtained to identify the type and extent of injury. Definitive management varies depending on the type and severity of injury.

Intracranial epidural hematoma (EDH) refers to bleeding between the dura mater and the calvarium. Most cases of EDH are traumatic, resulting from a head injury with an associated skull fracture that ruptures or tears the middle meningeal artery, which lies in close proximity to the skull and dura mater. EDH is more common in individuals 20–30 years of age, as the dura mater is not yet densely adherent to the calvarium at this age. The classic manifestation of EDH is an initial loss of consciousness, followed by a lucid interval in which the patient gains normal or near-normal consciousness, followed by rapid neurological decline. An ipsilateral dilated pupil (anisocoria) and contralateral hemiparesis are manifestations of transtentorial uncal herniation and signal imminent neurological decline. Neuroprotective measures to prevent secondary brain injury take precedence over diagnostic tests. Diagnosis is confirmed on a noncontrast CT head, on which EDH appears as a biconvex, hyperdense lesion, typically in the temporal or temporoparietal region. Surgical decompression with craniotomy is indicated in patients with large EDH, GCS ≤ 8, and evidence of neurological deterioration. Small, asymptomatic EDH in patients with GCS > 8 can be managed conservatively with close observation and serial CT scanning. The prognosis depends on several factors, including the GCS at presentation, size of the EDH, and, crucially, the time from the onset of brain herniation to decompressive surgery. Early intervention in patients with signs of brain herniation is associated with good neurological outcomes and lower mortality rates.

Subdural hematoma (SDH) refers to bleeding into the intracranial subdural space that is typically caused by a rupture of the bridging veins. Trauma, including minor falls, cerebral atrophy, and conditions that increase the risk of bleeding (e.g., coagulopathy, hypertension) are common etiologies of SDH. According to the onset of symptoms, SDH can be classified into acute SDH, subacute SDH, and chronic SDH. Acutely symptomatic SDH typically manifests with altered mental status, focal neurological signs, and signs of increased ICP, and it can progress to brain herniation and death if not treated. Chronic SDH manifests gradually with cognitive deficits, impaired memory, personality changes, and focal neurological signs. Subacute SDH can manifest with features of acute and/or chronic SDH. In patients with acutely symptomatic SDH, neuroprotective measures to prevent secondary brain injury take precedence over diagnostics. Diagnosis is confirmed with a noncontrast head CT, which would show a crescent-shaped (concave) lesion that may cross cranial sutures typically located in the supratentorial region. Surgery is recommended in SDH that is symptomatic, ≥ 10 mm in size, or causing ≥ 5 mm shift in the midline. Conservative management can be considered for small asymptomatic SDHs in patients with no signs of increased ICP.