A concussion is a mild traumatic brain injury that temporarily affects how the brain works. It results from a bump, blow, or jolt to the head, or a hit to the body that causes the head and brain to move rapidly back and forth inside the skull. This article clarifies the specific role of CT scans in concussion diagnosis.
The Nature of Concussion and CT Scan Limitations
A concussion is a functional injury to the brain. This means it disrupts the brain’s normal processes, rather than causing obvious structural damage. The brain’s function is temporarily impaired, leading to a range of symptoms.
A CT (Computed Tomography) scan uses X-rays to create detailed cross-sectional images of the head and brain. This imaging technique visualizes structural abnormalities within the skull, such as skull fractures, internal bleeding, or brain swelling.
A standard CT scan does not directly diagnose a concussion. Concussions involve changes that are not visible on a CT scan. Therefore, a person can have a concussion even if their CT scan appears normal.
Specific Situations Requiring a CT Scan
While a CT scan cannot confirm a concussion, it helps rule out more serious and potentially life-threatening brain injuries. These severe injuries can present with similar symptoms. A medical professional will order a CT scan if there are specific warning signs that suggest a more serious condition.
Indications for a CT scan following a head injury include prolonged loss of consciousness, persistent or worsening headaches, or repeated vomiting. Other symptoms are seizures, new weakness or numbness on one side of the body, and slurred speech. Increasing confusion, disorientation, or agitation also warrant immediate imaging.
Physical signs such as unequal pupil size or evidence of a skull fracture, like bruising around the eyes or behind the ears, also prompt a CT scan. Individuals taking anticoagulant medications (blood thinners) are at a higher risk for bleeding in the brain after a head injury, making a CT scan a necessary precaution. Very young children and older adults are often considered for scans due to their increased vulnerability or difficulty communicating symptoms.
The scan helps identify conditions such as intracranial hematomas (blood clots within or around the brain), brain swelling, or skull fractures that require immediate medical intervention. Detecting these structural injuries is the main purpose of a CT scan in head trauma.
Comprehensive Concussion Assessment
Since CT scans do not diagnose concussions directly, medical professionals rely on a comprehensive clinical evaluation. This assessment gathers information about the injury and the patient’s condition. It begins with a review of the injury event and the onset of symptoms.
A neurological examination evaluates various aspects of brain function. This includes checking vision, hearing, muscle strength, sensation, balance, coordination, and reflexes. Tests might assess eye movements or gait to identify any neurological deficits.
Cognitive testing assesses thinking skills. These evaluations may involve questions about memory, concentration, and attention. Such tests help determine if the brain’s cognitive functions have been affected by the injury.
The diagnosis of a concussion is made based on a healthcare professional’s judgment, considering the overall clinical picture, reported symptoms, and findings from physical and cognitive examinations. No single definitive test, such as a blood test or imaging scan, confirms a concussion.