What are the two settings for ultrasound?

• A. Continuous and pulsed
• B. Thermal and nonthermal
• C. High and low
• D. Static and moving

Answer: (A)

Ultrasound therapy is delivered in two main modes you set on the unit: continuous and pulsed. In continuous mode, the transducer emits energy without interruption for the entire treatment, producing more tissue heating. That thermal effect can help increase tissue extensibility, reduce stiffness, and improve blood flow when warming is beneficial. In pulsed mode, the energy is emitted in on/off cycles with a duty cycle less than 100%, so the average energy delivered is lower and heating is minimized. This mode emphasizes nonthermal mechanical effects, such as microstreaming and cavitation, which can support tissue healing and edema reduction without significant heating. The choice depends on goals and patient comfort: use continuous for thermal effects, use pulsed for nonthermal effects or when heating should be avoided. The other options describe outcomes or characteristics rather than the actual delivery settings.