What does the Doppler effect measure in sonography?

The Doppler effect in sonography measures the change in frequency of sound waves as they reflect off moving objects, such as blood cells. This principle is crucial for evaluating the flow of blood through vessels. When sound waves are emitted towards a moving object, like red blood cells, the frequency of the waves changes depending on whether the object is moving towards or away from the ultrasound transducer. If the object is moving closer, the frequency increases, resulting in a higher pitch, whereas if it is moving away, the frequency decreases, leading to a lower pitch. This frequency shift can be quantified and used to assess blood flow direction, velocity, and characteristics, providing valuable information for diagnosing various cardiovascular conditions.

Understanding the Doppler effect helps clinicians interpret how fast blood is moving and whether there are any obstructions or abnormalities in the blood flow, which is vital for effective patient management.