X-rays for the USMLE: Exam Questions and Preparation
How X-rays are tested on the USMLE, the findings to know, a preparation approach and original practice questions with explained answers.
Plain radiographs, mostly of the chest and abdomen, appear often and reward a calm, systematic read. Several findings call for immediate action, so recognizing them quickly matters.
Image-based questions appear on every Step: an ECG tracing, a radiograph, a photograph of the skin, a view of the retina, or a microscopic slide. The skill is the same each time: describe what you see in a fixed order, name the finding, then use it to answer the clinical question. This site does not host exam images, so each finding below is described in words, as many exam stems also do. Practice with an image-rich question bank and the official USMLE sample items to build your pattern recognition. The practice questions here are original and are not real exam items.
How X-rays is tested
Stems give an image or describe one and ask for the diagnosis or the next step, which is sometimes to treat before further imaging.
High-yield topics
- A chest radiograph routine: airway, breathing (lungs and pleura), cardiac and mediastinum, diaphragm and bones
- Pneumothorax and tension pneumothorax, pleural effusion and pneumonia
- Heart failure signs: cardiomegaly, vascular redistribution, Kerley B lines and effusions
- Free air under the diaphragm, bowel obstruction and other abdominal findings
- Widened mediastinum and aortic injury
- Fractures, foreign bodies and lines and tubes
Preparation approach
- Use the same order for every film, and describe the abnormality before naming it.
- Learn which findings are clinical emergencies that should not wait for another image.
- Compare normal and abnormal examples side by side in an atlas.
- Link each finding to the likely cause and the next step in management.
Practice questions
Question 1
A man has acute shortness of breath, hypotension and absent breath sounds on the left. His trachea is deviated to the right, and the left hemithorax is hyperlucent. What is the most appropriate next step?
- A. Chest radiograph before treatment
- B. Immediate needle decompression
- C. CT scan of the chest
- D. Observation and oxygen only
- E. Thoracentesis
Answer: B. This is a tension pneumothorax, a clinical diagnosis. Treat immediately with needle decompression and then place a chest tube. Do not delay for imaging.
Question 2
A woman has sudden, severe abdominal pain and a rigid abdomen. An upright chest radiograph shows free air under the right hemidiaphragm. What is the most appropriate management?
- A. Observation with oral intake
- B. Surgical exploration
- C. Barium enema
- D. Colonoscopy
- E. Oral antibiotics only
Answer: B. Free air under the diaphragm indicates a perforated hollow organ and peritonitis. Resuscitation, antibiotics and surgery are required.
Question 3
A stable man involved in a high-speed car crash has a widened mediastinum on a chest radiograph. What is the most appropriate next step?
- A. Discharge with observation
- B. CT angiography of the chest
- C. Barium swallow
- D. Echocardiogram in 1 week
- E. Repeat the chest radiograph in 24 hours
Answer: B. A widened mediastinum after blunt trauma suggests traumatic aortic injury. In a stable patient, CT angiography is the next test.
Make it a plan
Add a short daily image block to your study routine. See our Step 1 and Step 2 CK preparation timelines for schedules and weekly milestones. This article is general educational guidance and not an individualized study plan.
Educational content only. Confirm current exam requirements with USMLE.