4D Ultrasound (also known as 3D/4D Ultrasound) is the most advanced technology used by sonographers during pregnancy to evaluate the unborn fetus. This process provides physicians and expecting mothers with the clearest images of the fetus available. For over 35 years, obstetricians have used 2D ultrasound technology during pregnancies but are quickly shifting to the upgraded technology^{[citation needed]}. Sonographers are medical professionals who operate ultrasonic imaging devices to produce diagnostic images and scans, videos, or 3D volumes of anatomy and diagnostic data. ... A human fetus A fetus (or foetus, or fœtus – see below) is a developing mammal after the embryonic stage and before birth. ... This article needs cleanup. ...

2D ultrasound works by directing ultrasound waves (high frequency sound waves) straight down on the area being examined. These waves are reflected back up and recorded, providing the viewer with a "flat" black and white, 2-dimensional picture of the fetus. A fetus in its mothers womb, viewed in a sonogram (brightness scan) A fetus, aged 29 weeks, in a 3D ultrasound Ultrasound is sound with a frequency greater than the upper limit of human hearing, this limit being approximately 20 kilohertz (20,000 hertz). ...

3D ultrasound works in a similar fashion except that the ultrasound waves are directed from multiple angles. These waves are reflected back and captured, providing very detailed 3-dimensional images of the fetus including its hair, lips, eyes, nose, and other facial features. Placement of the placenta and umbilical cord can also be seen. 3D Ultrasound, which is the basis for 4D acoustical imaging, was first developed by Olaf von Ramm and Stephen Smith at Duke University in 1987^{[citation needed]}. The placenta is an ephemeral (temporary) organ present only in female placental vertebrates during gestation (pregnancy). ... In placental mammals, the umbilical cord is a tube that connects a developing embryo or fetus to its placenta. ...

4D ultrasound is the process of streaming 3D images into live, real-time video of the fetus. This allows viewers to see real-time motion. If the fetus re-adjusts its position within the womb, moves an arm, or even yawns, this can all be seen while using the 4D ultrasound technology. Female internal reproductive anatomy The uterus or womb is the major female reproductive organ of most mammals, including humans. ...

The 3D/4D ultrasound imaging should utilize ultrasound energy subject to the same limits as conventional (2D) ultrasound to create the Three- and Four-Dimensional images. If the system is used only in the Obstetrics Application, the ultrasound energy is limited by the manufacturer below FDA limits for obstetrical ultrasound, whether scanning 2, 3 or 4 Dimensionally. (The FDA limit for obstetrical ultrasound is 94 mw.cm^-2.)

Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ...

Ultrasounds can be used to determine:

• the sex of the fetus
• the age of the fetus
• the size of the fetus
• multiple pregnancies
• abnormal bleeding
• placental abnormalities
• placental location
• ovarian abnormalities
• Cleft lip and palate

Identical triplet brothers Quadruplet, quintuplet, etc. ... Cleft palate is a condition in which the two plates of the skull that form the hard palate (roof of the mouth) are not completely joined. ...

External links

• Web Site for individual certifications by the American Registry for Diagnostic Medical Sonography
• 3D ultrasound 4D Ultrasound Samples of 3D/4D Ultrasound Pictures as well as Multiple studies
• About the discovery of medical ultrasonography
• History of medical sonography (ultrasound)
• RadiologyInfo - The radiology information resource for patients: Ultrasonography