radcards ultrasound
Terms
undefined, object
copy deck
- when should you see the stomach at OB US
- by 16 weeks during 1 hour of scanning
- when should you see the bladder at OB US
- by 16 weeks
-
what measurement do you use to estimate age in the:
1st trimester
2nd
3rd -
1st trimester: CRL
2nd trimester: BPD
3rd trimester: FL or combination - what is a normal amniotic fluid index
- 7-25
- what is normal nuchal skin thickness
-
6mm or less measured at post fossa between 16-22 weeks
*pearl* >3mm anytime during 1st trimester is abnormal - what are the soft signs of down's syndrome
-
double bubble
endocardial cushion defect
nuchal skin thickness > 6mm
echogenic papilla
pyelectasis
echogenic bowel - where do you measure the uterine artery for resistive measurements, the umbilical artery
-
uterine artery: uterine wall
umbilical artery: the cord - what is a normal uterine artery resistance
-
low resistance system: changes from 2.0-1.7 over time
>3 at any time is abnormal - what is normal umbilical artery resistance
- changes from 4.3 (at 16w) to 2.5 (term) on average
- what is normal placental thickness
- 2-4 cm
- what percentage of cords with a single artery have fetal anomalies
- 50%
- ddx: thick umbilical cord
-
DM
polyhydraminios
urachal remnant tumor (cyst, carcinoma) (focal)
hemangioma (focal) - ddx: thin placenta
-
DM
vasculitis
HTN - ddx: thick placenta
-
hydrops fetalis
gestational diabetes
choriocangioma
oligohydramnios
TORCH - what percentage of fetuses with open spina bifida have elevated AFP, closed spina bifida
-
open: 90%
closed: 10% - what enzyme may be elevated in amniotic fluid of fetuses with spina bifida
- acetylcholinesterase
- ddx: elevated maternal AFP
-
A MINOR
atresia (espophageal)
multiple gestation
incorrect dates
neural tube defect
omphalocele/gastroschisis
renal anomaly - describe features of sacrococcygeal teratoma
-
graded as 1 thru 4 based on degree of intrapelvic extension
arise from hensen's node at the coccyx
are associated with hydrops and CHF
after 4 months malignant degeneration increasingly occurs (operate early!) - with what are cystic hygromas associated
-
turner's syndrome
trisomy
hydrops (virtually all) - what is the significance of ventriculomegaly in the fetus
-
virtually all have anomalies
*pearl* 10% have down's; 80% of down's have ventriculomegaly -
how often do trisomy 13 fetuses have holoprosencephaly
vice versa -
80%
50% - ddx: microcephaly
-
destruction (TORCH, anoxia)
subnormal growth (IUGR)
syndromic (meckel-gruber, trisomies)
CNS abnormalities - when is a choroid plexus cyst worrisome
-
associated with other abnormalities
large (>1cm)
bilateral - what is the triad of meckel-gruber
- polydactyly, large kidneys, encephalocele
- ddx: fetal cystic chest mass
-
CDH - bochdalek type
CPAM - type 1,2
bronchogenic cyst - ddx: fetal solid chest mass
-
CDH - morgagni type
sequestration
CPAM - type 3 - ddx: fetal small chest size
-
pulmonary hypoplasia
jeune syndrome
ellis van creveld
dwarf - how often is a double-bubble associated with duodenal atresia
- 40%
-
how often do fetuses with down's syndrome have double bubble
vice versa -
33%
20% - ddx: fetal/neonatal ascites
-
MUSHH
meconium peritonitis
urine ascites
storage disease (glycogen)
hydrops
hepatitis - what are causes of bilateral ovarian cysts
-
hormonal therapy
molar pregnancy
stein-levinthal syndrome
bilateral cystic neoplasm - what is normal thickness of the endometrial stripe
-
postmenopausal = 5mm
premenopausal - depends on phase of menstrual cycle - ddx: postmenopausal thick endometrium
-
carcinoma
polyp
hyperplasia - how can a thick endometrium in a postmenopausal woman be managed
-
5-8mm - hysterosalpingography, close f/u or Bx
>8mm - Bx - ddx: complex adnexal mass
-
CHEETA
cystadenoma/adendoca
hemorrhagic cyst
endometrioma
ectopic pregnancy
teratoma
abcess
hematoma - what features of an adnexal cyst are suspicious for malignancy
-
solid components
doppler flow in solid elements - ddx: enlarged ovary in young woman
-
functional cyst
ovarian torsion
polycystic ovary syndrome
ovarian mass - what are the features of stein-levinthal syndrome
-
oligomenorrhea
hirsutism
obesity
aka polycystic ovary syndrome - what findings suggest ovarian torsion
-
large ovarian size
peripheral follicles
cul-de-sac fluid
*pearl* there are no specific signs for ovarian torsion - what are the classic signs of ovarian teratoma
-
dermoid plug (focal echogenic shadowing nodule)
tip of the iceberg (can't see through it)
*pearl* you can mistake these for bowel! - what are the features you should evaluate in first trimester US
-
gestational sac
yolk sac
embryo
cardiac activity
CRL
uterine anatomy
placental location -
what are the parts of the double decidual sac sign
what does it indicate -
decidua parietalis
decidual capsularis
decidual basalis
it is highly associated (98%) with IUP - ddx: positive beta HCG without IUP
-
early IUP
ectopic
spontaneous abortion
molar pregnancy - what are features suggestive of ectopic pregnancy
-
no IUP
complex adnexal mass
complex cul-de-sac fluid
tubal ring
single decidual layer