Characteristic embryological finding: the head is more rounded and constitutes almost half of the embryo. The hand and feet approach each other. The upper limbs develop faster than the lower limbs, and toward the end of the 9th weeks, the fingers are almost entirely formed. The intestines are in the umbilical cord (Physiological midgut herniation).
3D ultrasound finding: Merz and coworkers were able to provide sticking images of the fetal face at this gestational age. They reported cases in which transvaginal 3D ultrasound produced remarkably well-defined facial image as early as 9 weeks gestation. Sometimes even the external ear can be depicted using 3D surface imaging. Hernation of the midgut is still present as it is a consequence of the rapid growth of the bowel and liver before closure of the abdominal wall. Although this is a physiologic phenomenon, it does not appear in each fetus. Possibly, we cannot, visualize it, or else its size may vary. At 10 weeks, the bowel undergoes to turn of 180 degrees, returning to its original position, at the same time that closure and development of the abdominal wall end. Cerebral hemispheres continue to develop during the 9th and 10th weeks of pregnancy. Visible are lateral ventricles containing hyperechoice choroid plexuses. The head is clearly divided from the body by the neck. External ear is sometimes depicted in the 3D surface image. Herniation of the midgut is present. Dorsal column, the early spine, can be examined in its whole length. The arms with elbow and legs with knees are clearly visible. Feet can be seen approaching the midline.
The size of the lateral ventricles increases rapidly. While the third ventricles is still relatively wide at the beginning of this week, its anteromedial part narrows due to the growth of the thalami. In the fetuses of 25 mm CRL and more, there is a clear gap between the rhombenchepalic and the mesencechepalic is narrow and in most cases, it is not visible in its complete length. The cavity of the dienchepalon decreases in the larger fetuses (CRL = 25mm), and become narrow, especially at its appear anterior part. The spine still characterized by two echogenic parallel lines.
3D power Doppler finding: Fetal structures are now clearly discernible and they are represented by distinct parts of the fetal body-head trunk and limbs. The head measures two-third of the entire body and becomesa distinct anatomical structure. The common and internal carotid arteries may be visualized at the end of the eighth gestational week and the beginning of the ninth week. A cerebral circulation (circle of willis and its major branches) can be documented at eight weeks in the form of discrete pulsation can be detected on tranverse section, lateral on the mesencephalon and chepalic flexsure.
3D ultrasound finding: Merz and coworkers were able to provide sticking images of the fetal face at this gestational age. They reported cases in which transvaginal 3D ultrasound produced remarkably well-defined facial image as early as 9 weeks gestation. Sometimes even the external ear can be depicted using 3D surface imaging. Hernation of the midgut is still present as it is a consequence of the rapid growth of the bowel and liver before closure of the abdominal wall. Although this is a physiologic phenomenon, it does not appear in each fetus. Possibly, we cannot, visualize it, or else its size may vary. At 10 weeks, the bowel undergoes to turn of 180 degrees, returning to its original position, at the same time that closure and development of the abdominal wall end. Cerebral hemispheres continue to develop during the 9th and 10th weeks of pregnancy. Visible are lateral ventricles containing hyperechoice choroid plexuses. The head is clearly divided from the body by the neck. External ear is sometimes depicted in the 3D surface image. Herniation of the midgut is present. Dorsal column, the early spine, can be examined in its whole length. The arms with elbow and legs with knees are clearly visible. Feet can be seen approaching the midline.
The size of the lateral ventricles increases rapidly. While the third ventricles is still relatively wide at the beginning of this week, its anteromedial part narrows due to the growth of the thalami. In the fetuses of 25 mm CRL and more, there is a clear gap between the rhombenchepalic and the mesencechepalic is narrow and in most cases, it is not visible in its complete length. The cavity of the dienchepalon decreases in the larger fetuses (CRL = 25mm), and become narrow, especially at its appear anterior part. The spine still characterized by two echogenic parallel lines.
3D power Doppler finding: Fetal structures are now clearly discernible and they are represented by distinct parts of the fetal body-head trunk and limbs. The head measures two-third of the entire body and becomesa distinct anatomical structure. The common and internal carotid arteries may be visualized at the end of the eighth gestational week and the beginning of the ninth week. A cerebral circulation (circle of willis and its major branches) can be documented at eight weeks in the form of discrete pulsation can be detected on tranverse section, lateral on the mesencephalon and chepalic flexsure.
No comments:
Post a Comment