OB normal anatomy and measurements (Correct
answers)
Fetal biometry= correct answers fetal measurements
transition from 1st to second trimester (wks) correct answers 12-13 weeks
start of 2nd trimester is time to transition from CRL to (4) correct answers BPD, HD, AC and FL
What view are HC and BPD measured in correct answers thalamic view
when is the BPD most accurate? correct answers 17-26wks
in 95% of the population, how accurate is BPD? correct answers +or- 11 days
what anatomy is found in the thalamic plane? (5) correct answers thalami, 3rd ventricle, falx
cerebri ant and post, CSP and choroid plexus
Is the cerebellum in the thalamic view? correct answers no
in BPD and HC, are scalp and skin included? correct answers no, just bone
how is BPD measured? correct answers outer to inner edge (leading to leading edge/near to far)
measurement of parietal bone (or, indicative of skeletal displasias) correct answers <3mm
common growth pattern of BPD correct answers 1st 2 trimesters: rapid growth, then slows down
3rd semester
how accurate is HC? correct answers +or- 2-3 wks
not including skin in ellipse, how do you measure the HC? correct answers outer edge to outer
edge of the cranium
Dating by HC is uneffected by_____________________________ correct answers head shape
what is EDC correct answers Estimated Date of Confinement
when HC more accurate than BPD? correct answers near EDC when head is in the pelvis
What is OFD? correct answers Occipital Frontal Diameter
What is the Cephalic Index? correct answers ratio of BPD to OFD of skull
(BPD/OFD x 100 = CI)
, how is the OFD measured? correct answers mid bone to mid bone
What should the CI be? correct answers 0.72 - 0.86
If the CI is higher than the normal range the head is wider than average...this is called correct
answers brachycephaly (Charlie Brown)
if the CI is lower than the normal range the head is narrower than average correct answers
dolichocephaly (Alien)
When is the HC used for? correct answers dating pregnancy when the CI is abnormal
Vertical Cranial Diameter (VCD) utilizes the coronal view which is
______________________________ to the ___________________________ view correct
answers perpendicular, thalamic
What is the 3D-BPD? correct answers the averageof the OFD and VCD (vertical cranial
diameter)
how accurate is the 3D-BPD (equivical to BPD on normal head shape) correct answers + or - 1 to
2 wks
Brachycephaly is often associated with correct answers platycephaly
Dolichocephaly is associated with correct answers oxycephaly (conical top)
What head measurement is not really used often. It can be a gestational measuring tool, because
the cerebellum is not effected by growth disturbances correct answers transcerebellar
this measurement is the distance between the lateral orbital rims for predicting gestational age
correct answers Binocular Distance(BD)
BD (binocular distance) is strongly related to correct answers BPD
IO and OD are measurements that are helpful in identifying (4) correct answers hypotelorism,
hypertelorism, anopthalmia and microphthalmia
Where is the AC measured? correct answers transversely at the level of where the umbilical vein
branches into the left portal sinus
What is the candy cane/hockey stick sign? correct answers (in AC plane) where the left and right
PVs form a "J" shape
Why is the AC measurement the least accurate? correct answers because it is indicative of
growth disturbances mainly LIVER influence
answers)
Fetal biometry= correct answers fetal measurements
transition from 1st to second trimester (wks) correct answers 12-13 weeks
start of 2nd trimester is time to transition from CRL to (4) correct answers BPD, HD, AC and FL
What view are HC and BPD measured in correct answers thalamic view
when is the BPD most accurate? correct answers 17-26wks
in 95% of the population, how accurate is BPD? correct answers +or- 11 days
what anatomy is found in the thalamic plane? (5) correct answers thalami, 3rd ventricle, falx
cerebri ant and post, CSP and choroid plexus
Is the cerebellum in the thalamic view? correct answers no
in BPD and HC, are scalp and skin included? correct answers no, just bone
how is BPD measured? correct answers outer to inner edge (leading to leading edge/near to far)
measurement of parietal bone (or, indicative of skeletal displasias) correct answers <3mm
common growth pattern of BPD correct answers 1st 2 trimesters: rapid growth, then slows down
3rd semester
how accurate is HC? correct answers +or- 2-3 wks
not including skin in ellipse, how do you measure the HC? correct answers outer edge to outer
edge of the cranium
Dating by HC is uneffected by_____________________________ correct answers head shape
what is EDC correct answers Estimated Date of Confinement
when HC more accurate than BPD? correct answers near EDC when head is in the pelvis
What is OFD? correct answers Occipital Frontal Diameter
What is the Cephalic Index? correct answers ratio of BPD to OFD of skull
(BPD/OFD x 100 = CI)
, how is the OFD measured? correct answers mid bone to mid bone
What should the CI be? correct answers 0.72 - 0.86
If the CI is higher than the normal range the head is wider than average...this is called correct
answers brachycephaly (Charlie Brown)
if the CI is lower than the normal range the head is narrower than average correct answers
dolichocephaly (Alien)
When is the HC used for? correct answers dating pregnancy when the CI is abnormal
Vertical Cranial Diameter (VCD) utilizes the coronal view which is
______________________________ to the ___________________________ view correct
answers perpendicular, thalamic
What is the 3D-BPD? correct answers the averageof the OFD and VCD (vertical cranial
diameter)
how accurate is the 3D-BPD (equivical to BPD on normal head shape) correct answers + or - 1 to
2 wks
Brachycephaly is often associated with correct answers platycephaly
Dolichocephaly is associated with correct answers oxycephaly (conical top)
What head measurement is not really used often. It can be a gestational measuring tool, because
the cerebellum is not effected by growth disturbances correct answers transcerebellar
this measurement is the distance between the lateral orbital rims for predicting gestational age
correct answers Binocular Distance(BD)
BD (binocular distance) is strongly related to correct answers BPD
IO and OD are measurements that are helpful in identifying (4) correct answers hypotelorism,
hypertelorism, anopthalmia and microphthalmia
Where is the AC measured? correct answers transversely at the level of where the umbilical vein
branches into the left portal sinus
What is the candy cane/hockey stick sign? correct answers (in AC plane) where the left and right
PVs form a "J" shape
Why is the AC measurement the least accurate? correct answers because it is indicative of
growth disturbances mainly LIVER influence
