There are many situations in which ultrasound is performed. Perhaps you are pregnant, and your obstetrician wants you to have an ultrasound to check on the developing baby or determine the due date. Maybe you are having problems with blood circulation in a limb or your heart, and your doctor has requested a Doppler ultrasound to look at the blood flow. Ultrasound has been a popular medical imaging technique for many years.


Photo courtesy Philips Research
Ultrasound examination during pregnancy

In this edition of How Stuff Works, we will look at how ultrasound works, what type of ultrasound techniques are available and what each technique can be used for.