OBGY AND BREAST IMAGING🗸

• Fluid present in between.
• Indicates endometrial fluid.

• Doppler should not be used in early pregnancy.
• Might cause a thermal effect on the embryo.

• FHR: M mode USG
• Surest sign of viability

• CRL → Most accurate for GA

Intradecidual sign:

• 1st sign to be seen

• 1st structure: Gestational sac

Double Decidual Sac sign:

A B (Amnion and Baby) → C (Chorion) → D (Decidua)

• Gestational sac surrounded by 2 rings:
• Inner ring: Decidua capsularis
• Outer ring: Decidua parietalis (vera)

• Obliteration of uterine cavity:
• 14-16 weeks
• (Fusion of inner and outer ring)

Yolk Sac.

• Appears within the gestational sac.

• Definitive sign of intrauterine pregnancy.

EMBRYO/Fetal Pole sign

Double bleb sign:

• Two circular structures.

• Structures are Yolk sac and Amnion.

• Amnion contains the fetal pole.

Heterotropic Pregnancy

• Ectopic + Uterine pregnancy

Confirmed sign of ectopic pregnancy:

• Gestational sac + yolk sac ± cardiac activity

• seen in fallopian tube.

Suspicion of ectopic if seen on USG:

• Adnexal mass (M/c finding on USG).

• Tubal ring / Bagel / Blob sign: (Only gestational sac +).
• Echogenic tubal ring surrounding ectopic sac.

Empty uterus.

Ring of fire appearance.

• Shows surrounding peripheral vasculature.





 

Ruptured ectopic pregnancy:

• Fluid accumulation in POD and paracolic gutters.

• Patient presents with shock.

• History of early trimester PV bleed.

• IOC for ectopic
• TVS >
• Serial β HCG

• Gold Standard
• Diagnostic Laparoscopy

Ix which may be done:

• S. progesterone.
• < 5 ng d/d
• Ectopic
• Abortion
• 20 - 25 ng
• Normal viable pregnancy

• Culdocentesis (Ruptured ectopic).

Ix never done:

• Hysteroscopy.

• HSG.

• Colpotomy (Drainage of pelvic abscess).

• Monochorionic Diamniotic:
• T sign is present.
• Mnemonic: Modi → Motti → T sign

• Dichorionic Diamniotic:
• Lambda sign / Twin peak sign is present.
• Membrane is thick.
• Mnemonic:
• Laddu → Lambda → DD
• Twin peak → twins → di di

• Dichorionic Monoamniotic Pregnancy cannot exist.
• Mnemonic: Chorion → Ch → Hc → House; Amnion → room

• USG findings:
• Multiple Cystic Spaces in the uterus.
• No fetal parts.
• Snowstorm appearance
• d/t Hydropic degeneration of placenta
• Edematous villi
• B/L Theca Lutein Cyst
• d/t Increased Beta HCG

• Placentomegaly

• Also known as Nasal bone NT scan.

• 1st Trimester screening for Down's Syndrome.

• Performed at 11 - 13 weeks + 6 days

NT should be measured:

1. Mid sagittal plane.

2. Between >11 & < 14 weeks or
   when CRL <84 mm.

3. Head should be in neutral position.

4. From inner border to inner border.

5. Amnion should be visible separately.

Combined Test:

• Dual test + USG Nuchal translucency (better sensitivity)

Findings increasing risk of Down's syndrome:

• Nuchal Translucency Thickness.
• Increase in >3mm
• Note: x 2
• 2nd trimester → Nuchal fold thickness ≥ 6mm

• Nasal Bone.
• Absence

• Finding is not specific

• Karyotyping is performed to confirm.

If NT ≥3 mm:

• Next step: Karyotyping (Diagnostic)
• In T1 material obtained by: Chorionic villi sampling

• Euploid → Fetal ECHO

• Mnemonic: Do (dual test) not (NT) cry (karyotyping)

Neural Tube Defects

• Most common congenital abnormality of neurologic system in children.

• Types
• Cranial + Caudal defect:
• Craniorachischisis
• Caudal defects:
• Meningocele,
• Meningomyelocele
• Cranial defects:
• Anencephaly
• Encephalocele (Herniation of brain tissue through a small defect covered by scalp, hair and meninges)

Diagnosis:

• Antenatal USG: Can pick up large NT defects.

• Maternal serum or Amniotic fluid markers.

• α-fetoprotein levels or Acetylcholinesterase levels.

• Neuroimaging to know extent

Anencephaly

• Failure of closure of the rostral or anterior neuropore
• By 4 weeks of life
• (the opening of the anterior neural tube).

• Brain tissue exposed to external environment

• Earliest anomaly detected on USG.

• Presents with Frog Eye Sign.

• Open calvarium is present.

• MTP needed.

Meningocele Vs Meningomyelocele

Myelomeningocele: (a type of spina bifida).

• Basic defect:
• Protrusion of neural components
• along with a sac formed by meninges
• through a midline vertebral defect.

• Spinal part and nerve roots present in sac.

• Black nerve roots seen going with the sac.

• Myelomeningocele pull downwards causing:
• Lemon Sign:
• frontal bones become concave.
• Banana sign:
• cerebellum becomes curved.

Meningocele:

• Herniation of meninges +/- brain tissue (meningoencephalocele) into the nasal cavity.

• Improper bone fusion during development creates a gap for herniation.

• Bones of nose roof:

Position	Bone
Anteriorly	Frontal bone
Middle	Cribriform plate
Posteriorly	Sphenoid bone

• Swelling is soft.

• Compressibility test: Positive.

• Reducibility test: Positive.

• Cough impulse test: Positive.
• Furstenberg test + → Cry/cough → ↑ Mass size
• Frustration - cry

• Transillumination test: Positive.

On spine

• On T1, appears dark.

• On T2, appears uniformly white.

• There is a protrusion of a meninges sac
• containing only clear fluid
• no neural components.

• Treatment:
• Excision of herniated mass.
• Reconstruction of defect.

Feature	Meningocele	Glioma	Dermoid
Cause	Improper fusion of bones of base of skull or roof of nasal cavity	No fusion → herniation → delayed fusion	Hamartoma: A congenital anomaly at line of bone fusion.
Consistency of swelling	Soft / Cystic	Firm	Variable
Compressibility test	Positive	Negative	Positive D- Compressible
Reducibility test	Positive	Negative	Negative
Cough impulse test	Positive	Negative	Negative
Transillumination test	Positive	Negative	Negative
Treatment	Excision + Reconstruction	Excision	Excision

 

Omphalocele

 

• Failure of reduction of physiological hernia.

• Sac present
• Cord attached to it.
• Comes through the midline
• Covering membrane of sac is present.

• Defect through umbilicus, (Sac → Central)
• Large defects (liver can herniate)

• Chronic

• Associated with congenital anomalies
• Beckwith Wiedemann syndrome
• Trisomy 13, 18, 21

Gastroschisis

 

• Defect is due to incomplete folding of embryo.

• Most common and acute and life threatening
• Risk of atresia, infection/perforation

• Split in the Anterior abdominal wall.
• Herniation from the defect
• Adjacent to the cord.

• Paraumbilical
• Defect adjacent to umbilicus

• Sac absent → Contain only intestinal loops
• (can get dry/shriveled)

• Fewer congenital anomalies

Management (Both): 

• Surgical (gradual closure to avoid abdominal compartment syndrome)

• Spalding Sign:
• Overlapping of fetal skull bones.

• Robert sign:
• Earliest sign.
• Intracardiac gas.
• Gas shadow in great vessels (Aorta, heart: 12 hrs).

• Assesses
• Umbilical Artery,
• Uterine Artery,
• Middle Cerebral Artery.

• Performed in 3rd trimester (32 weeks).

Umbilical Artery Doppler:

Uterine Artery Doppler

• Uses
• Predicts PIH
• Diagnosis of IUGR

• Done: 22-24 weeks POG

• Normal:
• Low resistance
• high diastolic flow.

• ↑ Risk of PIH:
• PI > Diastolic notch
• Increased Pulsatility Index
• 11-13 weeks
• Higher PI → Higher resistance.
• Persistence of diastolic notch
• Suggestive of high resistance.
• Normal upto 22 weeks
• After 22 weeks → suggest Preeclampsia
• Indicates high risk of
• Preeclampsia
• Uteroplacental insufficiency,
• IUGR
• PIH.

• Diagnoses early onset preeclampsia

• Indications: PIH, uteroplacental insufficiency, IUGR

Pulsatility Index (PI)

• For diagnosis of
• IUGR
• Early PIH

• PI = Peak Systolic Velocity – End Diastolic Velocity
  Mean Velocity

• Higher PI → Higher resistance.

• Normal Values
• Middle cerebral artery (MCA): increases with gestational age.
• Umbilical artery: decreases with gestational age.
• Uterine artery: normally decreases as pregnancy advances.

PI Value	Meaning	Example / Significance
Low PI, MCA	↓ Resistance in brain	fetal hypoxia → brain-sparing effect
High PI, Uterine A (> 95th percentile)	↑ Resistance	IUGR, preeclampsia, placental insufficiency

Abnormal MCA Doppler – Implications

• Brain-sparing effect
• Compensation for fetal hypoxemia
• ↑ Diastolic flow
• ↓ Pulsatility Index (PI)

• ↑ PI
• Indicates worsening oxygen deficit
• May suggest cerebral edema

• Reversal of MCA flow
• Severe abnormality
• Suggests cerebral edema / impending fetal demise

SD Ratio

• S/D Ratio = Peak Systolic Velocity / End Diastolic Velocity

• Reflects resistance to blood flow in a vessel.

• With advancing gestation → S/D ratio decreases
• (because placental resistance falls as more villi develop).

• Normal: <3

• In Uteroplacental insufficiency
• Increases
• ≥ 3 → ≥ 28 weeks
• Mild PIH → TOP ≥37 weeks

Findings	Meaning	Clinical Significance
MCA S/D ratio ↓	Fetal hypoxia	Brain-sparing effect
PI ↑↑(>95th percentile)	↑ Vascular resistance	Placental insufficiency, IUGR, Preeclampsia
Absent end-diastolic flow (AEDF)	Severe placental disease	Terminate > 34 weeks
Reversed end-diastolic flow (REDF)	Impending fetal death	Terminate > 32 weeks
Late decelerations / Loss of beat to beat variability	ㅤ	Immediate TOP

Abnormal Waveforms:

 

• IOC

• "Necklace pattern / String of pearls"

• Most specific
• ↑↑ Stromal volume/echogenicity
• Volume of ovary: ≥ 10 cc.

• Follicles:
• ≥ 12 follicles per ovary (or in both ovaries)
• Size: ≤9 mm.
• Arranged in periphery
• No dominant follicles

OHSS or Theca Lutein Cyst.

• Large follicles present throughout the ovary
• OHSS (Ovarian Hyperstimulation Syndrome):
• Seen in patients on infertility treatment.
• Theca Lutein Cyst:
• Seen in molar or twin pregnancy.
• Increase in Beta HCG is observed.

Additional Information:

• HSG is not a good investigation for these anomalies.

• Ideal Investigations:
• Hysteroscopy + Laparoscopy.
• Then MRI.
• Then 3D USG.

Differentiation between Bicornuate and Septate Uterus (by MRI):

• Echogenic mass in endometrium.

• Doppler: Feeding vessel sign
• vessel supplying mass
• (most common in endometrial polyp).

• Saline infusion sonography:
• Saline surrounds polyp

• Hyperechoic
• made of endometrial gland tissue

• Lies outside endometrial cavity.

• Hypoechoic.

• Popcorn calcification seen in pelvis.

USG Findings in Teratoma Ovary

• Tip of iceberg appearance

• Dot & dash appearance

• Rokitansky protuberance visualization

CT Scan of Pelvis Teratoma ovary

• Mass with Calcification (white) + Fat (dirty black)
• indicates a Teratoma/Dermoid.

• Popcorn calcification: Fibroadenoma

• Spiculated mass: Malignancy.

• Breast X-ray.

• Radiation exposure: 0.1-0.2 cGy.

• Machine identified by compression plates.
• Compression is a must.
• Makes breast density and thickness uniform.
• Improves penetration.
• Prevents overlapping of tissue.
• Allows for better screening.

• Contraindicated in acute painful conditions.
• Mastitis.
• Breast abscess.

Views:

Breast Abscess

• Hypoechoic area.

• Peripheral vascularity.

• Patient is a lactating mother with fever and pain.

BIRADS Score (Breast Imaging Reporting and Data System)

• Modalities → USG, MRI, Mammogram

Microcalcification:

• Highly suspicious of cancer.

• Needs biopsy.

• Corresponds to BIRADS 5.

• In decreasing order of risk of malignancy-
• Cluster microcalcification (maximum risk)
• Linear microcalcification
• Segmental microcalcification
• Diffuse microcalcification (minimum risk)

• Note
• Microcalcification → Suggests Malignancy
• Popcorn calcification → Fibroadenoma

Q. Benign or malignant?:

• Malignancy:
• Irregular/spiculated margins.
• Taller > Wider.

Benign lesion/Fibroadenoma → Imaging

• Phyllodes and fibroadenoma
• Intralobular stroma -MED12 mutation
• common origin

• Wider > Taller

• Macrocalcification

• Chunky / Popcorn calcification

• Corresponds to BIRADS 2.

Other benign calcifications

FibroadenomaLipoma / Hamartoma

• Breast in breast appearance

• Kinetic Curves can be performed.

Type 2

• Mnemonic: 2 → Plateau

Type 3 curve:

• Rapid Wash in and Rapid Washout.

• Suggestive of Malignancy.

Simple breast cyst

• Fluid-containing lesion.

• Exhibits Posterior Acoustic Enhancement.

Indications:

• Screening for young > 25 years & high-risk patients.

• Imaging of choice (IOC) for breast implants.

• Detection of recurrence vs. scar tissue.

• Most sensitive for Ductal Carcinoma In Situ (DCIS).

Torsion:

• Twist in vascular pedicle.

• Absent blood supply.

Epididymo Orchitis:

• Inflammation.

• Increased vascularity.

Doppler is IOC

• Image shows a Twisted Pedicle.
• Known as the Whirlpool Sign of Torsion.