Physics of Breast Ultrasound/Misc. Questions and Answers Latest Version Already Passed

Physics of Breast Ultrasound/Misc. Questions and Answers Latest Version Already Passed What is the main reason for using high-frequency transducers in breast ultrasound? They provide better resolution for superficial structures. What is the role of tissue impedance in ultrasound imaging? Tissue impedance affects how much sound is reflected back to the transducer, helping to create an image. Why is it important to adjust the gain during a breast ultrasound exam? To ensure the image contrast is optimized and important structures are visible. How does sound wave frequency impact penetration in breast ultrasound? Higher frequencies provide better resolution but less penetration, while lower frequencies penetrate deeper but with lower resolution. What does the term "acoustic impedance" refer to in breast ultrasound? 2 It refers to the resistance a tissue offers to the passage of ultrasound waves, influencing reflection and transmission. What is the function of the gel used in breast ultrasound? The gel serves to eliminate air between the skin and transducer, improving sound wave transmission. What effect does tissue density have on ultrasound imaging? Denser tissues tend to reflect more sound waves, appearing brighter (hyperechoic), while less dense tissues appear darker (hypoechoic). How does posterior acoustic enhancement occur in breast ultrasound? It occurs when an anechoic or fluid-filled structure transmits sound waves effectively, leading to increased brightness behind the structure. What is the primary function of a Doppler ultrasound in breast imaging? To evaluate blood flow within a lesion, helping to assess whether it is benign or malignant. How does the angle of insonation affect Doppler ultrasound results? 3 If the ultrasound beam is not aligned with the blood flow, it can lead to inaccurate flow velocity readings. Why is a linear array transducer typically used in breast ultrasound? Its high frequency allows for excellent resolution of superficial tissues, which is ideal for breast imaging. What role does the "beam profile" play in breast ultrasound? The beam profile determines the shape of the ultrasound beam, affecting how sound waves interact with tissues and influencing image quality. Why is tissue stiffness assessed in breast ultrasound elastography? Because malignant tissues tend to be stiffer than benign tissues, providing additional diagnostic information. How does frequency affect the axial resolution in breast ultrasound? Higher frequencies improve axial resolution, allowing for better differentiation of closely spaced structures. 4 What is the significance of the "focus" in an ultrasound image? The focus determines the area of the beam where the highest resolution occurs, improving image quality in that region. How does refraction affect breast ultrasound imaging? Refraction can cause distortion or misplacement