American Board of Internal Medicine (ABIM) Certification Practice Exam

Which imaging study is recommended for patients with TBI who have certain risk factors?

1. Magnetic resonance imaging

2. Ultrasound

3. Noncontrast head CT

4. X-ray

The correct answer is: Noncontrast head CT

In the context of traumatic brain injury (TBI), the recommended imaging study for patients exhibiting specific risk factors is a noncontrast head CT. This imaging modality is particularly valuable because it provides rapid assessment of potential intracranial hemorrhages, skull fractures, and other acute changes following the injury. Noncontrast head CT is preferred due to its speed and availability, making it crucial in emergency settings where timely diagnosis can significantly impact patient management and outcomes. This imaging captures detailed images of the brain and helps identify urgent conditions that may require intervention, such as subdural or epidural hematomas. While magnetic resonance imaging (MRI) can offer superior soft tissue contrast and is useful in evaluating more subtle injuries or diagnosing secondary complications later on, it is not typically the first-line imaging in acute TBI scenarios due to longer acquisition times and less availability in emergency settings. Ultrasound can be beneficial for certain assessments, particularly in pediatrics, but it lacks the comprehensive details provided by CT in the adult population with suspected TBI. X-rays primarily serve to evaluate bony structures and are not specific enough for assessing intracranial injuries, making them an unsuitable choice for the initial evaluation of TBI in the context outlined.