4. Placental Membranes
• Chorion (outer layer)
• Amnion (inner layer)
• Layers separated by fluid until wk 14-16
• Afterwards two membranes fuse
– Occasionally, chorioamniotic fusion fails
• Has no clinical significance
• Retroplacental complex
– Network of tubular lucencies beneath placenta
Maternal surface
- Termed basal plate
- Lie congruous with the deciduas basalis
- Irregular
Fetal Surface
- Termed chorionic plate
- Smooth
- Covered by amniotic membrane
Dr/AHMED ESAWY
5. The amnion is a thin but tough sac of membrane that covers
an embryo
Dr/AHMED ESAWY
6. Normal Placenta
• First seen on US at week 8
– Focal thickening
– Periphery of Gestational Sac
Dr/AHMED ESAWY
7. Normal Placenta
• Disc-like shape by week 12
– Finely granular
– Homogenous
– Smooth chorionic covering
– Grading of Placenta begins at end of 1st trimester
Dr/AHMED ESAWY
8. Normal Placenta
• As gestation
advances
–
heterogenous
–Focal
echolucencies
–Venous lakes
–Fibrin deposits
–Covers ¼
myometrium at
20w .1/8 at term
• Normal Placenta
Dr/AHMED ESAWY
9. • Subchorionic cystic spaces 10-15% blood
filledb sinuses may extend to basal plate
• Placentones,spiral arteries after 28 wk as
round free echoes ,color doppler
• Uterine wall vascularity in 3rd trimester
confusion with haematoma .color doppler
Dr/AHMED ESAWY
11. Placental Vascularity
Very vascular – has 2 blood supplies
Blood from fetus through 2 (sometimes 1) umbilical arteries through umbilical cord
from fetal hypogastric arteries to placenta
1 umbilical vein carries blood back to fetal left portal vein
Blood from mom through branches of uterine arteries through the myometrium
(arcuate arteries) through the basilar plate (spiral arteries) into the placenta
The two circulations intertwine in the placenta but do not mix
Exchange of oxygen and nutrients occurs over the large vascular surface area
Maternal venous channels in the placenta are hypoechoic or anechoic spaces called venous
lakes (usually small, but can be large)
Anatomy on US
Inner border of placenta (materanl) against the uterine wall has the combined hypoechoic
myometrium and interposed basilar layer = hypoechoic band called the decidua basalis
(contains maternal blood vessels)
Outer surface (fetal) abutting the amniotic fluid = chorionic plate (chorioamniotic
membrane) = bright specular reflector
Placental thickness judged subjectively
But if measure at midposition or cord insertion 2-4 cm = normal
Dr/AHMED ESAWY
15. Grade 2
Late 3rd trimester (~30 wks to delivery)
Larger indentations along chorionic plate Larger calcifications
in a “dot-dash” configuration along the basilar plateDr/AHMED ESAWY
16. Grade 3
39 wks – post dates
Complete indentations of chorionic plate through to the basilar plate
creating “cotyledons” (portions of placenta separated by the indentations)
More irregular calcifications with significant shadowing
May signify placental dysmaturity which can cause IUGR
Associated with smoking, chronic hypertension, SLE, diabetesDr/AHMED ESAWY
17. Grade 0: Placental body is homogeneous. The amniochorionic plate is even throughout. Late 1st
trimester-early 2nd trimester
Grade I : Placental body shows a few echogenic densities ranging from 2-4 mm in diameter.
Chorionic plate shows small indentations. Mid 2nd trimester �early 3rd trimester (~18-29 wks).
Grade�II : Chorionic plate shows marked indentations,creating comma-like densities which
extend into the placental substance but do not reach the basal plate. The echogenic densities
within the placental also increase in size and number. The basal layer comes punctuated with
linear echoes which are enlarged with their long axis parallel to the basal layer. Late 3rd trimester
(~30 wks to delivery)
Grade III : Complete indentations of chorionic plate through to the basilar plate creating
�cotyledons� (portions of placenta separated by the indentations) . 39 wks � post dates
Dr/AHMED ESAWY
25. Placental abruption. (a, b) Computed tomographic (CT) images show placental abruption after
a motor vehicle collision at 40 weeks gestation. The amniotic fl uid is high in attenuation
because of hemorrhage (arrow in a), making the devascularized placenta diffi cult to identify.
Careful inspection reveals an anterior and right lateral placenta (arrowheads in b), which has
only slightly higher attenuation than the amniotic fl uid.
Dr/AHMED ESAWY
26. c) Comparison CT image,obtained in a woman with pelvic fractures after trauma, shows
amniotic fl uid (F) with the attenuation of simple fl uid and a normally enhancing placenta (P)
with much higher attenuation. No retroplacental hemorrhage is seen, a fi nding consistent with
lack of abruption.
(d) US image shows placental abruption in another patient. A crescenteric collection of
predominantly hypoechoic fl uid lifts the edge of the placenta (P) away from the underlying
myometrium (M). The fl uid collection contains layering high-attenuation material (arrowhead),
a fi nding consistent with blood.
Dr/AHMED ESAWY
33. Placental hematoma. (a) US image shows a rounded collection of mixed-echogenicity material
(arrowheads) deep to the chorion along the lateral margin of the placenta. There is no internal
Doppler signal to suggest blood fl ow. This appearance is consistent with a subchorionic
hematoma
Dr/AHMED ESAWY
34. . (b) Axial T2-weighted SSFSE MR image shows a low-signal-intensity mass (H) along
the margin of the placenta (P). (c) Axial T1-weighted MR image shows the predominantly
intermediate-signal-intensity mass with internal areas of increased signal intensity (arrow). The
signal intensity characteristics and the location of the mass are consistent with a subchorionic
hematoma with hemorrhage of varying age.
Dr/AHMED ESAWY
36. Chorioamniotic separation. Transverse (a) and sagittal (b) images from obstetric US performed
at 20 weeks gestation show a free-fl oating membrane (arrowheads) surrounding the fetus (F).
This membrane is the amnion, which is completely separated from the underlying chorion; there
is even separation (arrow) over the surface of the placenta (P). This was a sporadic case of
chorioamniotic separation that caused no complications. The fetus was carried to term and was
found to be normal at birth. Dr/AHMED ESAWY
37. Subchorionic Hemorrhage
• Common < 20 wksGA
• Hemorrhage beneath
Chorion
– Separates easily from
Myometrium
• Caused by:
– Venous Blood
– Marginal Separation of
Placenta
Dr/AHMED ESAWY
39. Implantation Bleeding
• Non-specific Term
• Refers to Small Blood Collections
• Chorion attaches to Endometrium
• Essentially an early subchorionic bleed
• US to assess progression
Dr/AHMED ESAWY
44. Normally, the lower placental edge should be at least
2-3 cm from the margin of the internal cervical os.
Dr/AHMED ESAWY
45. Spectrum of placenta previa. (a) Transvaginal
US image obtained at 27 weeks gestation
shows a posterior placenta (P) without previa.
The most caudal tip of the placenta is nearly 5
cm (cursors) from the internal cervical os.
Distances greater than 2 cm are considered
normal.
(b) Transvaginal US image obtained
at 20 weeks gestation shows a low-
lying placenta (P). The placental
margin comes to within 0.7 cm of the
internal
cervical os
Dr/AHMED ESAWY
46. . (c) Transvaginal US image obtained at 19
weeks gestation shows marginal placenta
previa.
The placental tip (T) is located immediately at
the internal cervical os (O) but does not cover
it. P = body of the placenta
. (d) Transvaginal US image obtained at 19
weeks gestation shows complete placenta
previa.
The placenta (P) entirely covers the internal
cervical os (O). (e, f) Transabdominal US
image obtained at 18 weeks gestation
Dr/AHMED ESAWY
47. (e) and sagittal SSFSE MR image obtained at
29 weeks gestation
(f) show central placenta
previa. The placenta (P) entirely covers the
internal cervical os (O in e). In the case shown
in the US image,
the umbilical cord (C in e) inserts immediately
above the os. C in f = uterine cervix.
Dr/AHMED ESAWY
50. Incomplete/ partial placenta previa
The above ultrasound and color Doppler images show the lower margin of the placenta partially
covering the internal os, suggesting partial placenta previa.
Dr/AHMED ESAWY
51. One point to be noted is that placenta previa
is diagnosed in the 2nd and 3rd trimester of
pregnancy, and that normal uterine
contractions can cause the placenta to be
"pushed" lower down its normal position,
creating an appearance of placenta previa (a
false positive diagnosis of placenta previa).
Hence it is advisable to repeat the ultrasound
scan after 30 minutes to exclude a false
diagnosis of this condition.
Dr/AHMED ESAWY
52. Complete placenta previa
This ultrasound image shows the placenta completely covering the internal os (INT OS), thus
diagnostic of complete placenta previa.
Dr/AHMED ESAWY
53. Follow up ultrasonography is advisable
in all cases of placenta previa, to look
for ascent of the placenta to a higher
position due to the growth of the
uterus. Such cases of placenta previa
(both partial and complete) are in
danger of hemorrhage (antepartum)
and are advised rest to prevent this
Dr/AHMED ESAWY
55. Vase Previa
• Vasa previa refers to the presence of abnormal
fetal vessels within the amniotic membranes
that cross the internal cervical os. These
vessels are unsupported by Wharton jelly or
placental tissue and are at risk of rupture
when the supporting membranes rupture
Dr/AHMED ESAWY
56. Vasa Praevia
• Rare - 1 in 3000
• Fetal vessels run in the membrane below the presenting fetal
part, unsupported by placental tissue or umbilical cord
• Spontaneous or artificial rupture of membranes - rupture
these vessels - fetal exsanguination.
• Hypoxia if the vessels are compressed between baby & birth
canal.
• Fetal mortality 33-100%, if not diagnosed prenatally.
Dr/AHMED ESAWY
57. Pathology
• Unknown cause.
• Trophotropism - tendency of a plant to lean towards sun
to get light to survive. Lower segment not nourishing -
placenta grows upwards to reach more nourishing tissue.
• Risk factors
Low lining placenta
bilobed or succenturiate placenta
Velamentous insertion of cord
Multple pregnancies
IVF pregnancies
Dr/AHMED ESAWY
58. Vasa Previa
• Associated with velamentous insertion of the
umbilical cord (1% of deliveries)
• Bleeding occurs with rupture of the amniotic
membranes (the umbilical vessels are only
supported by amnion
• Bleeding is FETAL (not maternal as with
placenta previa)
• Fetal death may occur with trivial symptoms
Dr/AHMED ESAWY
61. Vasa previa. Transvaginal power Doppler US image obtained at 18 weeks gestation shows an
anterior placenta (P). There is vascular flow in a vessel (V) that is closely applied to the internal
cervical os (O). Follow-up US at 32 weeks gestation showed resolution of the vasa previa, thus
allowing subsequent uneventful vaginal delivery.
Dr/AHMED ESAWY
62. Velamentous insertion of cord
• 1% - singleton pregnancies, 8.7% - twin pregnancies, higher
in early pregnancy & spontaneous abortion.
• Umbilical cord usually inserts on placental mass - 99% cases.
• Velamentous - cord inserted on chorioamniotic membrane.
• Variable amount of cord unprotected by Wharton’s jelly.
• Vasa praevia coexisting in 6% singleton pregnancies with
velamentous insertion.
Dr/AHMED ESAWY
65. Velamentous insertion of umbilical cord into placenta:
These ultrasound and color doppler images
show the umbilical cord inserting into the
placental membranes before reaching the
placental tissue proper. This is the typical
appearance on sonography, of velamentous
insertion of the umbilical cord
Dr/AHMED ESAWY
67. Placenta implantation abnormalities
During the process of placenta development and
implantation, a defect in the normal decidua basalis from
prior surgery or instrumentation allows abnormal adherence
or penetration of the chorionic villi to or into the uterine wall
. The extent of adherence to and invasion of the
placental tissue varies:
1-Superfi cial invasion of the basalis layer is termed placenta
accreta (approximately 75% of cases);
2-deeper invasion of the myometrium is termed placenta
increta;
3-deeper invasion involving the serosa or adjacent pelvic
organs is termed placenta percretaDr/AHMED ESAWY
68. Placenta accreta
• Abnormal attachment of the placenta to the
uterine wall (decidua) such that the chorionic
villi invade abnormally into the myometrium
• Primary deficiency of or secondary loss of
decidual elements (decidua basalis)
• Associated with placenta previa in 5-10% of
the case
• Proportional to the number of prior Cesarean
sections
Dr/AHMED ESAWY
69. Placenta Accreta
• Abnormal Adherence to Uterine Wall
• US Findings
– Retroplacental Complex absence of
vascular channels
– Increased echogenicity of tissues deep to
the placenta
– Visualization of RP Vessels w/in bladder
lumen
– +/- also seen placenta previa
• Risk Factors
– Prior C-section
– Prior Placenta Accreta
– Prior Placenta Previa
• Two Categories
– Placenta Increta: Invades wall
– Placenta Percreta: Penetrates wall
• Missing Decidua Basalis and RPComplex
Dr/AHMED ESAWY
70. Placenta Accreta
• Placenta accreta
– Accreta = adherent to endometrial cavity
– Increta = placental tissue invades myometrium
– Percreta = placental tissue grows through uterine
wall
Accreta caused by faulty development
of NITABUCH’S LAYER
Dr/AHMED ESAWY
71. Warning Signs of Placenta
implantation abnormalities
• 1-loss of retroplacental clear space
• 2-reduce myometrail thickness (less than 3
mm)
• 3-exaggerated placental lacunae
• 4-abnormal color doppler imaging patren
• If any signs seen warning us
Dr/AHMED ESAWY
72. Ultrasound signs of Placenta
implantation abnormalities
• 1-disrupted retroplacental clear space
• 2-myometrail thining or invasion
• 3- 1-disrupted retroplacental blood flow
• 4-moth eaten or swiss chees appearance
• 5-abnormal vascular channels
Dr/AHMED ESAWY
78. Spectrum of placenta accreta. (a) US images show disruption of the normal hypoechoic
myometrium (black arrowheads) by invading placental tissue (white arrowheads). B = bladder,
P = placenta.
Dr/AHMED ESAWY
79. (b) Sagittal SSFSE MR image shows
intermediate-signal-intensity placental tissue
(arrowhead) invading the normal dark
myometrium (M) in the lower uterine segment,
fi ndings consistent with placenta accreta.
(c) Sagittal SSFSE MR image shows
obliteration of the normal dark myometrium
(M) posteriorly, with placental tissue of
heterogeneous signal intensity (arrowheads)
penetrating the full thickness of the uterine
wall. This appearance is indicative of placenta
percreta.
Dr/AHMED ESAWY
82. Hydatidiform Mole
• Hydatidiform mole is classified as complete or partial molar
pregnancy on the basis of cytogenetic, morphologic, and clinical
features.
• Complete molar pregnancy is thought to arise as a result of abnormal
fertilization (of an empty ovum). In this condition, the normal
placenta is replaced by hydropic villi, which are seen at US as multiple
tiny cystic spaces, giving a "snowstorm" appearance . In complete
moles, a fetus is absent except in the rare event of a coexistent twin
pregnancy. This is most likely to occur when there is fertilization of
multiple ova, one of which was empty.
• At US, if a hydatidiform mole is seen in association with a fetus, it can
be difficult to distinguish a twin complete mole–normal fetus
combination from a singleton partial mole with a triploid fetus
(resulting from fertilization of a normal ovum by two haploid sperm).
However, identification of a separate normal placenta would help
exclude a partial mole with a triploid fetus
Dr/AHMED ESAWY
83. Vesicular mole (also called Molar pregnancy
or Hydatidiform mole) in 1st trimester
• Sonography of the uterus was
done in this 1st trimester
pregnancy. a) Hyperechoic
mass in the uterine cavity
with multiple cystic spaces
within it. b) Uterus is enlarged
(bulky) c) The myometrium is
hypoechoic compared to the
contents of the uterine cavity.
These appearances can be
likened to a "snowstorm"
Dr/AHMED ESAWY
84. Complete mole. (a) Longitudinal US image of the uterus
shows distention of the uterine cavity by echogenic material
(M). The echogenic material has the classically described
snowstorm appearance of a complete mole. The normal
hypoechoic myometrium (U) can be seen at the periphery.
C = internal cervical os
Dr/AHMED ESAWY
85. .US image shows a multicystic structure within the uterus,
a finding consistent with a complete mole. No identifiable
fetal tissue was present. Molar tissue can be variable in
morphology Dr/AHMED ESAWY
86. CT image of a patient with a β-hCG level of 620,000 mIU/mL shows a predominantly low-
attenuation mass in the uterus with heterogeneous foci of internal enhancement. Pathologic
examination demonstrated a complete mole without myometrial invasion. The multicystic
structure posterior to and to the right of the uterus is an enlarged ovary with theca lutein cysts.
CT can be used to assess for invasion by gestational trophoblastic disease
Dr/AHMED ESAWY
87. Partial mole. US image shows echogenic material filling the majority of the uterine cavity.
Adjacent to this material is a gestational sac containing an embryo (arrowhead). These findings
were due to a pathologically proved partial mole. The differential diagnosis for this appearance
includes a large subchorionic hemorrhage. These two entities can be distinguished on the basis
of the β-hCG level and the presence of vascular flow within the molar tissue. No flow would be
expected in a hemorrhage.
Dr/AHMED ESAWY
88. • Complete hydatidiform mole with a coexistent fetus at 13
weeks gestation. (a) Axial transabdominal US image of the
uterus shows a large posterior hydatidiform mole (M), a
separate anterior placenta (P), and a live fetus (F).
Dr/AHMED ESAWY
96. What Is The Recommended Subsequent Test ?
β subunit hCG
Dr/AHMED ESAWY
97. What Is The U/S Differential Diagnosis?
US scanning revealed
Dr/AHMED ESAWY
98. What Is The U/S Differential Diagnosis?
Complete mole with a coexisting normal twin
Partial mole
Other placental abnormalities
Rtroplacental hematoma
Degenerating myoma
Dr/AHMED ESAWY
99. Vesicular mole (also called Molar pregnancy or
Hydatidiform mole) in 1st trimester
Dr/AHMED ESAWY
100. Magnified transverse sonogram
shows a complete hydatidiform
mole (CHM
Sagittal endovaginal sonogram of a complete
hydatidiform mole (CHM) at 12 weeks of
menstrual age demonstrates an enlarged
endometrium containing an anembryonic
gestational sac with adjacent hyperechoic
Transverse endovaginal sonogram of a
second-trimester complete hydatidiform
mole (CHM) demonstrates a distended
endometrial cavity containing
innumerable, variably sized
Transverse endovaginal sonogram of a
second-trimester complete hydatidiform
mole (CHM). Note that retained products of
conception may mimic a hydatidiform mole
complete
hydatidiform
mole
Dr/AHMED ESAWY
101. Invasive mole versus choriocarcinoma
MRI may be needed to confirm myometrail invasion
Malignant GTD
Dr/AHMED ESAWY
102. Increase intratumoural blood flow
Focal areas of myometrail invasion seen as
increase in myometrail vascularity focally
Malignant GTD
Invasive mole versus choriocarcinoma
Dr/AHMED ESAWY
103. Invasive mole versus choriocarcinoma
Presence of extrauterine gestational disease ,poved by
doppler
Malignant GTD
Dr/AHMED ESAWY
104. Invasive mole in a patient with an elevated β-
hCG level. B = bladder, R = rectum. (a) Axial
T2-weighted MR image shows a bright mass in
the uterine fundus. The mass disrupts the
normal dark myometrial line (M) in the left
lateral uterus (arrowheads), a finding
consistent with invasion. Pathologic
examination demonstrated invasive gestational
trophoblastic disease
. (b) Gadolinium-enhanced MR image shows
avid enhancement of the mass (arrowheads).
Dr/AHMED ESAWY
105. Choriocarcinoma. (a) Sagittal T2-weighted
MR image shows a mass of
heterogeneous signal intensity (white
arrowheads) in the uterine fundus; the
mass invades into the posterior uterine
wall. The internal foci of low signal
intensity (black arrowhead) are fl ow voids,
which are suggestive of marked
vascularity. (b) Contrast-enhanced T1-
weighted MR image shows avid
enhancement of the mass (white
arrowheads). The low-signal-intensity
flow voids are seen in the posterior
uterine wall, and the mass has central low
signal intensity (black arrowhead), which
represents necrosis. The mass was a
pathologically proved choriocarcinoma.
(c) Contrast-enhanced CT image obtained
2 years later shows a low-attenuation
lesion in the liver (arrowhead), a fi nding
consistent with metastatic disease. There
were also metastases in the pancreatic
head and lungs.
Dr/AHMED ESAWY
107. RPOC. (a, b) Transverse gray-scale (a) and power Doppler (b) US images show echogenic
material in a fl uid-fi lled distended endometrial canal (arrowheads). There is no evidence of
internal vascularity. In a patient with vaginal bleeding and a history of pregnancy, these fi ndings
are consistent with RPOC.
Dr/AHMED ESAWY
108. (c, d) Sagittal T2-weighted (c) and contrast-enhanced spoiled gradient-recalled acquisition in
the steady state (d) MR images, obtained in another patient, show a mass in the uterine fundus
(arrowheads) that invades the myometrium. The mass has heterogeneous signal intensity on the
T2-weighted image and is isointense on the T1-weighted image with uniform enhancement, fi
ndings consistent with RPOC.
Dr/AHMED ESAWY
109. The above ultrasound images show a post partum uterus on
transabdominal sonography. There is a hyperechoic mass within the
endometrial cavity measuring 8 x 5 cms. The color Doppler ultrasound
image shows poor vascularity of the mass and the endometrium.
Transverse section ultrasound image of the post partum uterus shows
that the mass is located more towards right half of the uterine cavity;
also note that the endometrial mass is eccentric within the cavity- the
anterior myometrium is thicker whilst the posterior wall of the uterus is
thinner. The placenta was not expelled at the time of delivery. Thus this
eccentric, markedly thick, inhomogenous mass is the retained placenta
with a certain degree of placenta accreta being present. Absence of
vascularity or poor flow does not rule out retained products of
conception/ retained placenta. The single most important sign of
retained products of conception is the large endometrial mass. Other
signs of retained placenta or products include complex fluid or
thickened endometrium (more than 10 mm.).
Dr/AHMED ESAWY
110. subchorionic cyst of the placenta. Also
known as membranous cyst, chorionic cyst
cystic lesion of the
placenta, just below
the placental surface.
Few mobile echoes
were seen within the
lesion. This finding is
generally considered
to be clinically of little
significance .
Dr/AHMED ESAWY
113. Placental calcification
• This 3rd trimester
pregnancy shows extensive
calcification of the basal
plate (uterine or maternal
surface) of the placenta.
Clinically and pathologically,
calcific changes of placenta
have no significance .
Dr/AHMED ESAWY
115. SUBJECTIVE
FACTOR
CALCIFICATION associations
with………….
1. Fetal distress in labor
2. Poor perinatal outcome,
3. Maternal smoking
4. First-time mothers
5. Preeclampsia,
PLANE OF THE VIEW.
GAIN FACTORS
SETTINGS
EXPERIENCE OF THE
OBSERVER.
TEXTURE OF PLACENTA
INEDNTATIONS OF THE
CHORIONIC PLATE
CALFICATION
INTERPRETATION.
Dr/AHMED ESAWY
116. Sonography of the placenta in this 16 week pregnancy shows a large, solid mass, that
is non calcific and shows mild vascularity on Power Doppler imaging. The mass is
inhomogenous and shows many cystic spaces within it. This tumor of the placenta lies
close to the cord insertion site. Flow seen on Power Doppler image suggests that this
placental tumor is vascular and excludes placental hematoma. Ultrasound images of
this type of placental mass are highly suggestive of placental chorioangioma. The
other diagnostic possibility can be a hamartoma of the placenta. Chorioangioma of
placenta is the commonest tumor of the placenta and is benign in nature. This mass
measures 12 x 8 cms., an unusually large size for a chorioangioma, and can signify
poor prognosis for this pregnancy. Images courtesy of Jaydeep Gandhi, MD, India.
These ultrasound images were taken with a Toshiba Nemio-30 Ultrasound system
Dr/AHMED ESAWY
117. Placental cyst. Doppler US image shows an anechoic spherical structure (arrowhead) on the fetal
surface of the placenta. The structure is immediately adjacent to the insertion of the umbilical
cord. There is no internal fl ow, a fi nding consistent with a placental cyst.
Dr/AHMED ESAWY
118. Amniotic Band Syndrome
• Disruption of Amnion
• Fetus enters Chorion
• Fetus entangles
• Amputation
deformities
Dr/AHMED ESAWY
120. Chorioangiomas
• Hemangiomas or Hamartomas
• Common on pathologic placental examination
• Rare finding on Ultrasound
• Unpredictable masses: follow-up needed
• Sonographic Findings
• Focal,encapsulated
• usually round
• well-defined
• increased color Doppler perfusion differentiated it from haematoma
• contour change is seen on fetal surface of placenta
• May mimick placental hematomas
Dr/AHMED ESAWY
121. placental chorioangioma
• Sonography of the placenta in
this 16 week pregnancy shows a
large, solid mass, that is non
calcific and shows mild
vascularity (vascular) and
excludes placental hematoma.
and shows many cystic spaces
within it. This tumor of the
placenta lies close to the cord
insertion site. Ultrasound images
of this type of placental mass are
highly suggestive of placental
chorioangioma.
Dr/AHMED ESAWY
123. Placental mass (mass in placenta - Chorioangioma of placenta or Placental Chorioangioma):
Dr/AHMED ESAWY
124. Chorioangioma. (a) Power Doppler image shows a heterogeneous mass on the fetal surface of
the placenta with internal vascularity and a large feeding vessel (arrow). (b) Gray-scale US image
shows the large, well-circumscribed mass arising from the surface of the placenta (P)
immediately adjacent to the insertion of the umbilical cord (C). This is the classic location for a
chorioangioma.
Dr/AHMED ESAWY
125. large chorioangiomas may associated with A-V shunting
Heart failure,polyhydramnios
Dr/AHMED ESAWY
126. Other Placental Vascular Issues
• Venous Lakes
• Commonly found on ultrasound
• No sinificance in normal fetuses
• Helpful finding in placenta accreta-percreta
• Velamentous Cord Insertion
• Vasa Previa
• Associated with Velamentous CI, or
• Succenturiate lobe
Dr/AHMED ESAWY
127. Placental venous lake
This placenta, in a 28 week pregnancy shows a large
hypoechoic (almost anechoic), measuring 5 x 3.5 cms. in size.
Some particulate matter was seen flowing through this area,
which was closer to the fetal surface of the placenta. These
ultrasound images suggest a typical appearance of a large
venous lake in the placenta. Color Doppler image showed no
major flow pattern within this placental lake. The fine,
echogenic strands within the lesion appear to be nothing
more than artefacts produced by slow flowing blood within
the lesion..
Dr/AHMED ESAWY
131. Normal placenta.
(a) US image shows a placenta (P) that is relatively homogeneous in echotexture.
The retroplacental clear space is hypoechoic (arrowheads).
(b) Sagittal single-shot fast spin-echo (SSFSE) T2-weighted MR image shows a placenta (P) with
intermediate signal intensity. The dark line represents the retroplacental clear space
(arrowheads).
Dr/AHMED ESAWY
134. BILOBED
• Equal size
• Central cord insertion
• Lobes are attached by chorionic tissue
• May be asscicaited with velamintous cord
insertion
Dr/AHMED ESAWY
135. Bilobed placenta. (a) Diagram shows a bilobed placenta. (b) US image shows
a bilobed placenta. The two lobes of the placenta (P1 and P2) are separated by a thin bridge of
placental tissue that covers the internal os. In this case, the umbilical cord (arrowhead)
inserts into the bridge of tissue. Dr/AHMED ESAWY
137. Succenturiate placenta
• Different size lobes
• Eccentric and velamintous cord insertion
• Lobes are attached by membranes
Sequelae
velamintous cord insertion
RPOC
haemorrhage
Dr/AHMED ESAWY
138. Succenturiate placenta. (a) Diagram shows a placenta with a succenturiate lobe. (b) US image
shows a placenta (P) with a succenturiate lobe (S). The main body of the placenta is located
along the posterior uterine wall. A second soft-tissue structure of the same echogenicity but
located anteriorly is the succenturiate lobe. (c) Sagittal SSFSE MR image shows a normal
placenta (P) with a succenturiate lobe (S). The main body of the placenta is located along the
posterior uterine wall. A second soft-tissue structure with similar signal intensity is seen along
the anterior uterine wall and represents the succenturiate lobe.
Dr/AHMED ESAWY
139. Succenturiate placenta
Synonyms: bilobed or bilobate placenta
This was a 3rd trimester pregnancy showing part of the placenta along the anterior wall of the
uterus (SUCCENT PL), and the main part of the placenta along the posterior wall (PL). The
sucenturiate lobe of placenta is connected to the main placenta by a string of blood vessels (see
Color Doppler image on right). Both images taken on a GE, Logiq-3 ultrasound system.
Dr/AHMED ESAWY
142. Diagram shows a placenta membranacea.
Velamentous insertion of the umbilical cord. Doppler US image shows insertion (I) (white
arrow) of the umbilical cord into a thin membrane of tissue extending from the margin (black
arrow) of the placenta (P).
Dr/AHMED ESAWY
148. Placenta fenestrata ; central area of placenta
atrophied to leave only membrane . Central
portion of a discoidal placenta is missing
In some instances, there is an actual hole in
the placenta but more often the defect involves
only villous tissue with the chorionic plate
mistakenly considered to indicate that a missing
portion of placenta
• Aetiology unknown
Dr/AHMED ESAWY
155. Twin gestations
• T sign in a Monochorionic-
diamniotic Twin Gestation
• Twin peak sign in DICHORIONIC-
DIAMNIOTIC TWIN GESTATIONS.
Dr/AHMED ESAWY
156. (8) Twin peak sign in dichorionic-
diamniotic twin gestations. (a) US
image of an early twin gestation shows
the separate placentas converging at
the insertion of the amniotic
membrane (arrowhead), forming the
so-called twin peak that is
characteristic of a dichorionic-
diamniotic gestation.
(b) Sagittal SSFSE MR image shows
similar fi ndings, with the twin peak (*)
formed by the two placentas.
Arrowhead = intertwin
membrane. (9)
Dr/AHMED ESAWY
157. T sign in a monochorionic-diamniotic twin gestation. US image of an
early twin gestation shows the amniotic membrane (arrowhead) separating the amniotic
sacs of twins A and B. The membrane has a fl at interface with the single placenta (P).
Dr/AHMED ESAWY
158. Placental Abnormalities
- Circulatory Disturbances-
Placental Vessel Thrombosis
When a stem artery from the fetal circulation in the placenta is
occluded, it produces a sharply demarcated area of avascularity
Single a thrombosis : 5% of placentas in normal pregnancies
10% of diabetic woman
Thrombosis of a single stem artery will deprive only 5% of the
villi of their blood supply
associated with fetal growth restriction and stillbirth
- Benirschke and Kaufmann, 2000 -
Dr/AHMED ESAWY
159. Placental Abnormalities
- Hypertrophic Lesions of the chorionic villi -
skriking enlargement of the chorionic villi is commonly seen in
association with
severe erythroblastosis
fetal hydrops.
maternal diabetes
fetal CHF
maternal-fetal syphilis
Dr/AHMED ESAWY
160. Placental Abnormalities
-Placental Inflammation-
Changes that are now recognized as various forms of degeneration
and necrosis were formerly described under the term placentitis
e.g.) Small placental cysts with grumous contents were formerly
thought to be abscesses.
Nonetheless, especially in cases of preterm and prolonged
membrane rupture, bacteria invade the fetal surface of the placenta
→ chorioamnionitis
Dr/AHMED ESAWY
161. Placental Abnormalities
-Tumors of the Placenta-
Tumor Metastatic to the Placenta
Malignant tumors rarely metastasize to the placenta
Melanoma (1/3), leukemias and lymphomas 1/3
Tumor cells usually are confined within the intervillous space
- the fetus : metastases (¼)
Malignant cells seldom proliferate to cause clinical disease
Embolic Fetal Brain Tissue
Fetal brain tissue occasionally is seen embolized to the placenta or
fetal lungs
Usually has been described with “traumatic” deliveries
This phenomenon is not without precedent because brain tissue has
been found in pulmonary veins following head trauma in older
children and adults
Dr/AHMED ESAWY
162. Abnormalities of the Membranes
- Chorioamnionitis-
Imflammation of the fetal membranes is usually manifestation of
imtrauterine infection
Associated with prolonged membrane rupture and long labor
Characteristic
: clouding of the membranes
foul odor (depending on bacterial species and concentaraion )
Definition
: mono-and polymorphonuclear leukocytes infiltrate the chorion,
the resulting microscopical finding - cells origin : maternal
Leudocytes are found in amnionic fluid (amnionitis) or the umbilical
cord(funisitis) - cell origin : fetus
< 20 wks almost all polymorphonuclear leukocytes : maternal origin
> 20 wks: Inflammatory response : maternal & fetal
Preterm deliveries : m/c
Dr/AHMED ESAWY