PAEA Surgery End Of Rotation (EOR) Practice Exam

Which diagnostic imaging is part of the work-up for suspected subarachnoid hemorrhage?

1. X-ray

2. CT scan

3. MRI

4. Ultrasound

The correct answer is: CT scan

In the assessment of suspected subarachnoid hemorrhage (SAH), a CT scan is the preferred imaging modality. This is primarily due to its speed and effectiveness in detecting the presence of blood in the subarachnoid space soon after the event. A CT scan can typically visualize acute blood and is more likely to yield positive results within the first 72 hours following the onset of symptoms. These include sudden severe headaches, often described as a "thunderclap headache," which is frequently associated with SAH. While other imaging techniques such as MRI and ultrasound are valuable in other contexts, they are not the first-line choices for diagnosing SAH. MRI, for example, is more sensitive for chronic hematomas and other brain conditions but takes longer and is less accessible in emergency situations. Ultrasound can sometimes be utilized, particularly in pediatric cases or in specific clinical scenarios, but it is not routinely used for SAH work-up. X-rays are helpful for certain conditions in the head and neck but do not provide the necessary information to diagnose subarachnoid hemorrhage effectively. Therefore, the CT scan is the most appropriate and effective tool in the initial evaluation of suspected SAH due to its rapid acquisition of images and high sensitivity for acute bleeding.