What is the purpose of a coupling cushion in ultrasound therapy?

The purpose of a coupling cushion in ultrasound therapy is to facilitate effective transmission of ultrasound waves from the transducer to the skin surface without the use of water. The coupling cushion serves as a medium that reduces air gaps, thereby enhancing the efficiency of ultrasound therapy. This is particularly useful for treating irregular surfaces, as the cushion can conform to the skin's contours and ensure consistent contact.

In scenarios where water is not practical — such as treating areas of the body that are difficult to keep submerged or when specific equipment setups are necessary — the coupling cushion provides an effective alternative. It allows for the therapeutic ultrasound to penetrate the tissue without losing energy due to air pockets that would normally occur between the transducer and skin.

Other options don’t describe the role of a coupling cushion accurately. For instance, enhancing electrical conductivity generally relates to different therapeutic modalities. Treating submerged surfaces does not apply here since the purpose of the coupling cushion is specifically to avoid submersion. Measuring pulse rates is unrelated to the function of ultrasound therapy or the coupling cushion altogether.