In ultrasonography, what does 'acoustic enhancement' refer to?

'Acoustic enhancement' refers to an increase in the echo amplitude from structures that are deeper to an anechoic structure, such as a fluid-filled cyst, in ultrasonic imaging. When sound waves pass through an anechoic area—like a liquid-filled space—they encounter less resistance compared to surrounding tissues. This results in more sound waves being transmitted through the anechoic area, which leads to an increase in the brightness of the echoes produced from structures located deeper, enhancing their visibility on the ultrasound image.

This phenomenon is important in clinical practice as it assists in differentiating fluid-filled structures from solid masses. For instance, when a sonographer identifies a cyst, the enhanced echoes from the tissues behind it help confirm the presence of a benign fluid collection as opposed to a solid tumor, where this enhancement would not occur. By understanding acoustic enhancement, clinicians can make more accurate diagnoses and management decisions based on ultrasound findings.