Rosh Emergency Medicine Practice Test 2025 - Free Emergency Medicine Practice Questions and Study Guide

The primary imaging modality used to diagnose aortic dissection is a chest CT scan. A CT scan is highly effective in quickly and accurately identifying the presence of an aortic dissection due to its ability to visualize the entire aorta and surrounding structures in great detail. It provides comprehensive information about the dissection, including the location, extent, and whether there is any involvement of branch vessels, crucial for determining the appropriate treatment strategy.

While other imaging modalities such as X-ray and ultrasound may provide some information, they are not as definitive or detailed as a chest CT when it comes to diagnosing aortic dissection. X-rays can sometimes show indirect signs of dissection but lack specificity. Ultrasound can be used in specific scenarios, particularly in unstable patients or when a quick evaluation is needed, but it is limited in its ability to visualize the full aorta compared to CT. MR angiography is also a possible option for evaluation but is less commonly used in emergency settings due to time constraints and its availability. Overall, the chest CT scan stands out as the most reliable and widely utilized imaging method in this context.