Chapter 49 Second and Third Trimester Flashcards
Fetal anatomy can accurately be assessed after _____ weeks.
18
Most common fetal position where back of fetal head to maternal pelvis.
vertex/cephalic
When the lower extremities or buttocks are found to be in the lower uterine segment and the head is visualized in the uterine fundus.
Breech
Fetus laying perpendicular to maternal long axis.
transverse
By the ____ week of gestation, the fetal bones ossify.
12
Normal fetal brain parenchyma appears ________ because of the small size reflectors and high water content in the tissue. The sulcus and gyrus are more echogenic.
hypoechoic
The _______ tissue within the lateral ventricles produces the CSF. This sponge like material is echogenic and is very prominent in early pregnancy.
choroid plexus
From the lateral ventricles, the fluid travels to the third ventricle through the ________ . From the third ventricle, the fluid travels though the _________ to the forth ventricle.
foramen of Monro, aquaduct of Sylvius
The normal atrium measures ______. If the atrium measures greater than ______, this warrants serial imaging and further evaluation.
6.5mm, 10mm
The ______ is located in the back of the cerebral peduncles within the posterior fossa. The cerebellar hemispheres are joined together by the ________.
cerebellum, cerebellar vermis
The ________ is the sonographic term that describes the Arnold-chiari malformation in which the cerebellum may be small or displaced downward into the foramen magnum.
banana sign
The ________ (a posterior fossa cistern filled with CSF) lies directly behind the cerebellum.
cisterna magna
The normal cisterna magna measures ______, with an average size of ______.
3-11 mm, 5-6 mm
The second trimester, the thickness of the _________ is measured in a plane containing the cavum septi pellucidi, the cerebellum, and the cisterna magna.
nuchal skin fold
values of skin thickness of _______ up to 20 weeks GA are normal.
5mm or less
Fetuses with thickened nuchal skin are at increased risk for _______.
aneuploidy
The apex of the fetal heart is directed toward the _____ anterior chest with the right ventricle closest to the chest wall and the left atrium closest to the spine.
left
Normal heart rhythm and rate of _____ beat per min.
120 to 160
Stomach becomes apparent as early as the _____ week and full stomach should be seen in all fetuses beyond the ____ week of gestation
11th, 16th
Beyond ____ weeks gestation, small bowel may be differentiated from large bowel.
20
The large bowel typically contains mesconium particles and may measure up to _____ in the perterm fetus.
20 mm
The kidneys are apparent as early as the ____ week of pregnancy.
13th
A renal pelvis greater that ____ beyond 30 weeks GA is considered abnormal.
10mm
The adrenals are seen as early as the _____ week of pregnancy and by _____ weeks assume a rice-grain appearance.
20th, 23th
Gender may be seen as early as _____ and become clear by the ______ week.
12-16, 20-22nd
The umbilical vein transports oxygenated blood from the _______ where as the paired umbilical arteries return deoxygnated blood from the iliac arteries of the fetus to the placenta for purification.
placenta
Amniotic fluid increases until the ____ week and then slowly diminishes.
34th
Normal cervix is ____ or longer.
3cm
