Task: Answer Verification
Input (English): Question: Is the imaginary line method reliable for identification of prosthetic heart valves on AP chest radiographs?
Answer: The well known imaginary line method is of limited value when identifying prosthetic valve positions on supine AP CXR's. We advocate the use of the "valve orifice" method or the "perceived direction of blood flow" method to gain valuable information regarding the presence and position of prosthetic heart valves.
Output (English): no