placental pathology Flashcards
Fibroid versus contraction
Equivalent sonographic appearance
Braxton-Hicks relaxes with time
what is cervical incompetence
Painless spnataonous dilation of the cervix
cervical incompetence can cause what
second trimester preganncy failre
nomral cervix
at least 30mm
cervical incompetnce meaurement
less than 25mm at 24 weeks
what are risk factors for cervical incompetence
history of preterm labour or borth
PROM
uterine abnormalities
multiple gestations
what is cord prolapse
presentation of the umbilical cord in advance of presenting fetus during labour and deverlivery
cord proplase may lead to what
Sono detection is clinically important b/c it may lead to cord compression and fetal vascular compromise
1st trimester umbilcal cord cysts
defined as echolucent area within the umbilical cord with YS separate
if cystic cord masses are seen between 7 and 13 weeks
20% are associated with chromosal strctural defects
when is fetal abnormality more likley (cystic cord masses)
more likley if a cyst is close to the placenta or close to the fetus or if it persists beyond 12 weeks GA
what does vasa previa result in
fetal hypoxia or fetal blood loss
what can occur in vasa previa during labour
Can be easily compressed or rupture when uterine contractions or membrane rupture occurs
vasa previa is associated with what
bleeding
fetal morbidity
what is vasa previa
Condition where umbilical vessels run within membranes near or across the internal cervical os
what is velamentous insertion
umbilical vessels separate and course b/t the amnion and chorion at a distance from the placental margin surrounded only by a fold of amnion
velamentous insertion is asscoiated with what
Devoid of Wharton’s jelly Associated with cord compression Poor fetal growth Thrombosis Miscarriage Prematurity Lowe birth weight Fetal malformation Perinatal death Low apgar scores Placenta previa Vasa previa Retained placenta
what is marginal insertion known as
Battledore placenta
in marginal/battledore placenta
CI is within a cenitmere of the placental margin
what is umbilical vein vanix
focal dilation of the umbilical vein
usually seen intraabdominal
umbilcal vein varnix diameter
greater than 9mm
umbilcal vein varnix outcome
usually normal
what anomalies can be associated with umbilcal vein varnix
Aneuploidy
Perinatal death
Hydrops
fetusues with SUA have a high rate of structural anomaies
Cardiovascular Malformations CNS Gastrointestinal Genitourinary defects MSK Malformations
what chromosomal abnormalities can be associated
trisomy 13 and trisomy 18
SUA is asscoiated with
Growth restriction
prematurely
increased perinatal mortality rate
what is PMD
relatively recently recognized, rare placental vascular anomaly characterized by mesenchymal stem villous hyperplasia.
placentomegaly
often clinically mistakenly as partial hydatidiform mole
Fetus may be completely normal or have intrauterine growth restriction (IUGR)
Sono appearance of choriocarcnoma
Focal, hemorrhagic nodule within endometrium
Secondary masses to cervix or vagina
Metastasis to liver
symptoms of choriocarcinoma
cough
hemoptysis
neurologic disturbances or hemorrhage
what is choriocarcinoma
Abnormal tissue beyond the myometrium that is capable of mets
when does choriocarcinoma occur
50 % arise after a molar pregnancy
25 % arise after abortion
25 % after a normal pregnancy
invasive mole sonographic appearacne
focal areas of increase echogenicity
what is invasive mole
characterized by proliferation of trophoblats and presence of chorionc vill within the endometrium and myoetrium
what can invasive mole sometimes cause
This focal invasion can, on rare occasions, penetrate through the myometrium and blood vessels, causing uterine rupture and potential death from severe intraperitoneal hemorrhage.
Complete hydatifiform mole
molar pregnancy
what is the sono appearance of a moLar poregancy
Distention of the uterine cavity with a heterogenous echogenic mass “snow storm appearance”
complete mole
Absence of amniotic fluid and a fetus
partial mole
presence of co-excistng fetus along wuth an enlarged thickened placenta with mutlple cystic spaces
what abnormaloty is noted in most molar pregnancies
triploidy
Severe IUGR and fetal anomalies
Complete hydatidiform mole characterization
Characterized by chorionic villi that are markedly hydropic, swollen and proliferation of the trophoblast cell
Results in excessive production of b HCG
signs of molar pregnany
Uterine enlargement
Hyperemesis gravidarum
Vaginal bleeding
gestational trophoblastic disease
encompassses disease processes that originate within the placenta
can be benign or malignant
what is gestational trophoblastic neoplasia
complciation of pregnancy results from an abnormal proliferation of trophoblastic tissue
benign trophoblastic disease
hydatiform mole (complete or partial mole)
malignant trophoblastic disease
invasive mole
choriocarcinoma
PSTT
ETT
chorioangioma sonographic appearance
Well circumscribed hyperechoic or hypoechoic ovoid mass protruding form the fetal surface of the placenta
Near cord insertion
May see necrosis or calcifications
Increased vascularity
what is chorioangioma
benign vascular malformation
what is chorangioma assciated with
Elevated maternal AFP or bHCG
what fetal complications can chorioangioma lead to
Anemia Heart failure Nonimmune hydrops Thrombocytopenia Polyhydramnios IUGR Prematurity Placenta abruption
Placenta abruption prognosis
Depends on degree of placenta detachment and gestational age Fetal growth restriction Oligohydramnios PTD (preterm delivery) Fetal Demise
Placenta abruption symtptoms
Acute abdominal and pelvic pain
Vaginal bleeding
Uterine tenderness
Fetal distress
placenta abruption risk factors
Maternal HTN (hypertension) Drug use Smoking Trauma Uterine anomalies PROM (Premature rupture of mebranes)
what is placental abruption
Premature separation of all or part of the placenta from the underlying myometrium
Occurs in 1 in 120 pregnancies
Bleeding in decidua basalis occurs with separation
how is placenta abruption classified
Classified according to the location of separation
Occurring hemorrhage:
Retroplacental
Intraplacental
Marginal
Subchorionic blood clot (may be at a distance from the placenta with or without vaginal bleeding).
placenta infarcts sono appearance
Evolve through acute, subacute, and chronic stages
Majority hypoechoic in acute stage; ultrasound may be unable to distinguish them from intraplacental hemorrhages
Calcification may occur over time.
what is placental infarction
Placental infarction occurs as a result of obstruction of the spiral arteries and is usually found at the periphery of the placenta.
what is a placental lake
Placental infarction occurs as a result of obstruction of the spiral arteries and is usually found at the periphery of the placenta.
what is a finding of placental lakes during second semester indicative of
A finding of placental lakes during the second-trimester ultrasound scan does not appear to be associated with uteroplacental complications or an adverse pregnancy outcome.
q
placental invasion
Abnormal penetration of placental tissue beyond endometrial lining of uterus
placenta accreta
Chorionic villi attach to myometrium without muscular invasion.
placenta increta
is further extension of the chorionic villi into the myometrium.
placenta percreta
penetration of the chorionic villi through the uterus.
what is placenta increta the result of
Placenta increta results from underdeveloped decidualization of endometrium.
what is the best way to idnetify lower uterine segment
transvag
complications of placental previa
Preterm delivery Maternal hemorrhage Increased risk of placental invasion Increased risk of postpartum hemorrhage IUGR
factors associated with placenta previa
Advanced maternal age Smoking Cocaine abuse Prior placental previa Multiparity Prior cesarean section Uterine surgery
Placenta previa
implantation of the placenta completely crosses the internal os
marginal (partil previa)
edge of the placenta is abut or covering the os
low lying placenta
edge of the placenta is near but not abutting the os
< 2.0 cm from Internal os
amniotic bands sonographically
collapsed amnion images, multiple linear wavy echoes
amniotic bands are linear echoes transversing the amniotic cavity
in most cases amniotic bands
Do not disturb the fetus
amniotic band syndrome can result in what
feral entanglement
Can result in limb deformities, spine and facial abnormalities, amputation
what may abnormal membranes present as
without complications or with vaginal bleeding
Circumvallate placenta
Attachment of the placental membranes to the fetal surface of the placenta rather than to the underlying villous placental margin
what does circumvallate placenta result in
Results in placental villi around the border of the placenta that are not covered by the chorionic plate. Rim forms (Fibrinoid tissue) Most cases have no clinical significance
what ay circumvallate placenta be associated with
Maternal bleeding Placenta Abruption Preterm loss Oligohydramnios Involved in amniotic band syndrome
Bilobed placenta
Two lobes that are similar size
Separated by membranes with some vascular connation between the lobes
Communication of placental tissue between the lobes (chorionic bridge).
The cord commonly attaches to a thin connecting rim of chorionic tissue which bridges the two lobes.
Succenturiate lobe
Visu: 6 % of cases
Connected to main placenta by – vessels with in a membrane or by a bridge of membranes
Main Placenta- larger & is where Umb. Cord inserts
Visu. of Accessory Lobe –clinical relevant b/c of increased risk of infarction, placenta previa, vasa previa, postpartum and hemorrhage assoc. with retained accessory lobe
