Overview
From Transient Dysfunction to Expanding Brain Injury
A head injury can produce a temporary change in how the brain functions, a bruise within brain tissue, or bleeding that progressively compresses the brain.
A head injury can produce a temporary change in how the brain functions, a bruise within brain tissue, or bleeding that progressively compresses the brain. The first assessment may look reassuring even when the injury is evolving, so the patient’s trajectory matters as much as the initial finding. A concussion results from rapid acceleration–deceleration forces that cause neuronal metabolic dysfunction and transient functional impairment without structural injury. The patient may have headache, confusion, amnesia, dizziness, nausea, impaired balance, or visual change. A loss of consciousness is not necessary. A concussion diagnosis follows a head-impact event accompanied by at least one of these symptoms and a Glasgow Coma Scale (GCS) score of 13–15. A contusion is different: it is a bruise to brain tissue. Local bleeding and swelling can produce a focal deficit or worsen over time. An epidural hematoma is usually an arterial collection between the skull and dura, classically associated with temporal bone trauma and middle meningeal artery injury. A patient may briefly lose consciousness, appear to recover, and then deteriorate during a so-called lucid interval. That interval is...