You might be most familiar with sonography's role in the field of obstetrics to produce an ultrasound image of an unborn baby. Sonography is also used to analyze tissues and organs of the body, such as the heart, eyes and abdomen.
Etymology: Pierre S. de Laplace, French physicist, 1749-1827. a principle of physics that the tension on the wall of a sphere is the product of the pressure times the radius of the chamber and the tension is inversely related to the thickness of the wall.
Pressure at which a blood vessel collapses and blood flow stops. Laplaceâs Law. Force acting on blood vessel wall is proportional to diameter of the vessel times blood pressure. Measurement of BP. Blood pressure cuff is inflated above systolic pressure, occluding the artery.ressure at which a blood vessel collapses and blood flow stops. Laplaceâs Law. Force acting on blood vessel wall is proportional to diameter of the vessel times blood pressure. Measurement of BP. Blood pressure cuff is inflated above systolic pressure, occluding the artery.