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.
While each male adolescent is different, the following are average ages when puberty changes may occur: Beginning of puberty: 9.5 to 14 years old. First pubertal change: enlargement of the testicles. Penis enlargement: begins approximately one year after the testicles begin enlarging. Appearance of pubic hair: 13.5 years old. Nocturnal emissions (or wet dreams): 14 years old. Hair under the arms and on the face, voice change, and acne: 15 years old. Girls also experience puberty as a sequence of events, but their pubertal changes usually begin before boys of the same age.