Also, Doppler can detect abnormal blood flow within the heart, which can indicate a problem with one or more of the heart's four valves. Color Doppler. Color Doppler is an enhanced form of Doppler echocardiography. With color Doppler, different colors are used to designate the direction of blood flow.
Quick Answer. The age at which people grow armpit hair varies, but for boys it is often between the ages of nine and 14. Girls typically begin to grow this hair between eight and 13 years of age. Keep Learning.
Male Growth Patterns. Boys generally hit their growth spurt about two years after girls, according to KidsHealth.org. Most boys grow most quickly between ages 12 and 15 and stop growing by age 16, but this depends on when they reach puberty. Boys usually continue developing muscles and gaining weight after they stop growing taller. The average adult male in the United States is about 69 inches tall, according to the CDC.