The Beam Uniformity Coefficient (BUC) is a measure of the uniformity of the ultrasound beam as it travels through tissue. It is a dimensionless ratio that compares the maximum intensity of the beam to the average intensity. A BUC value of 1 indicates a perfectly uniform beam, while a value less than 1 indicates a non-uniform beam.
The BUC is calculated by dividing the maximum intensity of the ultrasound beam by the average intensity. The maximum intensity is typically determined by the peak amplitude of the ultrasound wave, while the average intensity is calculated by taking the average of the intensity measurements at multiple points along the beam.
BUC is important in ultrasound imaging because it affects the quality and accuracy of the images produced. A non-uniform beam can result in uneven image brightness and distortion, making it difficult to accurately interpret the images. BUC also plays a role in the safety of ultrasound procedures, as a non-uniform beam can lead to areas of high intensity that may cause tissue damage.
The BUC typically decreases with depth in tissue due to the attenuation of the ultrasound beam as it travels through the tissue. This means that the beam becomes less uniform as it travels deeper into the tissue. Factors such as tissue composition and wave frequency can also affect the BUC at different depths.
The BUC can be improved by using techniques such as focusing the ultrasound beam, using higher frequency waves, and using different transducer designs. These methods can help to reduce the effects of attenuation and produce a more uniform beam. Additionally, regular maintenance and calibration of ultrasound equipment can also help to ensure a more uniform beam and improve the BUC.