Which statement correctly describes compliant balloons?

• A. Soft and flexible
• B. Very stiff and rigid
• C. Do not expand with increased pressure
• D. Always provide precise diameter control

Answer: (A)

Compliant balloons are designed to be soft and flexible, so their diameter increases as you inflate them. This makes them mold to the vessel and lesion contours, allowing gradual dilation at lower pressures and reducing the risk of abrupt, uncontrolled sizing. Because they expand with pressure, you can’t rely on a fixed, precise diameter with a compliant balloon—overexpansion can occur if pressure rises too much. In contrast, noncompliant balloons are stiff and maintain a nearly fixed diameter even at higher pressures, providing more precise sizing. So the statement that best describes compliant balloons is the soft and flexible one.