ROLE OF DOPPLER ULTRASONOGRAPHY IN

OBSTETRICS

PRESENTOR:DR.Y.RAMA CONSULTANT:DR.VEENU

SENIOR RESIDENT:DR.AJAY KUMAR

BASICS OF DOPPLER

• Pitch altered with change in relative motion b/n observer & object- DOPPLER SHIFT

• FORMULA:

fD= 2fo v cos 0/v

TYPES OF DOPPLER USG

CONTINUOUS WAVE DOPPLER PULSED DOPPLER: Brief pulses of ultrasound waves Vessels visualised on gray scale and flow

velocity patterns obtained

SAMPLE VOLUME

DOPPLER GATE

COLOR DOPPLER

Stationary targets-B-mode image

Signals from moving targets-display color

Color assigned – direction of flow

RED – TOWARDS

BLUE-AWAY

DOPPLER INDICES

PSV-peak systolic velocity-A

EDV-end diastolic velocity-B

Systolic /diastolic ratio

RI-resistive index:(A-B)

A

PI-pulsatility index:(A-B)

Mean

POWER DOPPLER

• Detects energy or amplitude of doppler signals of moving blood

• Independent of direction

• Subtle amount of flow

• Velocity –not obtained

INDICATIONS IN OBSTETRICS

• LOCALISATION OF GESTATIONAL SAC

• EARLY PREGNANCY FAILURE

• FAILED TERMINATION OR RETAINED PRODUCTS OF CONCEPTION

• PREDICTION OF PREECLAMPSIA

• INTRAUTERINE GROWTH RETARDATION

• TWIN GESTATION

• FETAL HYDROPS AND ANEMIA

• PLACENTAL AND CORD ANAMOLIES

• STRUCTURAL ANAMOLIES OF FETUS

SAFETY OF DOPPLER IN PREGNANCY

• Epidemiologic studies- association of LBW, delayed speech devn

• More research

CURRENT RECOMMENDATIONS & GUIDELINES

• Initial power setting lowest to produce adequate images-ALARA(As low as reasonably achievable) principle

Operator-color flow box small, Exposure time, non stationary probe

• Preexisting temperature elevation of mother

• Sensitive tissues-head, brain, spine,eye (esp.<8w)

• Thermal and mechanical indices

VESSELS AND NORMAL WAVEFORMS

UTERINE ARTERY:

ANATOMY:

branch of anterior division of internal iliac artery-on levator ani-isthmus-upwards on lateral sides of uterus in leaves of broad ligament

NORMAL WAVEFORMS

DOPPLER MEASUREMENT AND WAVEFORM

• At the cervico corporal junction

NORMAL WAVEFORMS

NORMAL PI<1.2 NOTCH PI>1.45

PREGNANT NON PREGNANT PREGNANT

Extravillous trophoblast from anchoring villi- into decidua-spiral artery

innervated muscular

vessels of high resis- tance--- passively dilated low resistance

Vasodilatory peptides-increase in maternal blood flow

NORMAL WAVEFORMS

COILED SPIRAL ART

UNCOILED SPIRAL ART

EXTRAVILLOUS TROPHOBLASTIC CELLS

SPIRAL ART

FETO MATERNAL CIRCULATION

UMB V

DUCTUS VENOSUS

DESC.AORTA

UMB ART

IVC

UMBILICAL ARTERY Information on perfusion of fetoplacental

unit

Measured in extraabdominal portion

NORMAL WAVEFORMS

NORMAL WAVEFORMS

Growth of placenta ; increase in Cardiac output 1. increase in systolic & diastolic velocities 2.continuous forward flow 3.decrease in impedance

3rd TM PI:1-1.5

1st TM

UMBILICAL VEIN • From extra abdominal portion

• Blood flow increases as gestation progresses-Pulsations disappear

NORMAL WAVEFORMS

1st TM 3rd TM

DUCTUS VENOSUS • Oblique section of

upper abdomen or midsagittal section

• Doppler measurements- sample volume at the initial or middle portion

• Distal portion-contaminates IVC, HV

NORMAL WAVEFORMS

Continuous forward flow throughout cardiac cycle

BIPHASIC

S wave---ventricular systole

D wave---diastole

A wave---forward flow at atrial

contraction

NORMAL WAVEFORMS

D A

S

THORACIC AORTA • Descending thoracic

aorta flow throughout cardiac cycle

NORMAL WAVEFORMS

MIDDLE CEREBRAL ARTERY

Easier to detect

Sensitive to detect IUGR

Transverse axial view- slightly caudal than for BPD measurements

Sample volume at the proximal part and the flow towards probe

High systolic and low diastolic velocities– auto regulation

NORMAL WAVEFORMS

PI>1.45

LOCALISATION OF GESTATIONAL SAC

TO DIAGNOSE ECTOPIC:

TRUE GESTATIONAL SAC

Double decidual sign-

•Oval & eccentric

PSEUDOGESTATIONAL SAC

Single echogenic layer

•central

ENDOMETRIUM

ENDOMETRIUM ONLY EMBRYO & TROPHOBLAST

Ectopic: Sac - No peritrophoblastic flow

Low velocity flow(<21cm/sec)

TO DIAGNOSE ECTOPIC:

Ectopic: Adnexa- RING OF FIRE

DD:Corpus luteal cyst-low resistance ;low vel flow

Ectopic – Low resistance ;high vel flow

Cardiac activity - M mode /color /power doppler

MASS

RING OF FIRE

TO DIAGNOSE ECTOPIC:

• Interstitial & cornual ectopic-when no significant mass seen

• CDI:increased flow

TO DIAGNOSE ECTOPIC:

MONITOR METHOTREXATE THERAPY

• To assess placental flow- absent or persistent-after treatment

CERCIVAL SCAR IMPLANTATION

• Past H/O caesarean

• Sac in LUS and local myometrial thinning

• Significance:distinguish ongoing abortion dead embryo no peritrophoblastic activity

• Catastrophic hemorrhage-even bladder involvement can occur

PREDICTION OF PREECLAMPSIA

• Insufficient invasion of maternal spiral arteries by trophoblast

impaired placental

perfusion

Increase in RI or notching-dec placental flow

NOTCH

UTERINE ART

FAILED TERMINATION

• RETAINED PRODUCTS OF CONCEPTION

• large echogenic mass filling endometrial canal extending into myometrium

• CDI- mass of vessels in the myometrium &high velocity flow

• No flow-non viable –pass spontaneously

• To plan D & C

Vessels in myometrium

INTRAUTERINE GROWTH RESTRICTION

• resistance in uteroplacental circulation

• velocity in feeding arteries esp. Diastolic

• Changes in uterine, umbilical, MCA, Aorta, ductus venosus

UTERINE ARTERY • Notch

• Mean P.I. Of both uterine arteries >1.45

• placenta on one side- ipsilateral waveform reported

NORMAL PI<1.2

NOTCH MEAN PI>1.45

UMBILICAL ARTERY-PROGRESSIVE CHANGES

ABSENT EDF

REVERSAL EDF

NORMAL

MIDDLE CEREBRAL ARTERY

• Fetal hypoxia

• Chemoreceptors sense

• Inc flow to brain for oxygen(most sensitive)

• diastolic vel(dec P.I.)--REDISTRIBUTION

NORMAL PI>1.45

THORACIC AORTA

• Absent end diastolic velocity(adaptation to inc flow to brain)

• Hypoxia,distress,IUGR impedance impedance in aorta in brain absent EDV

NORMAL

DUCTUS VENOSUS

Dec cardiac function

Dec forward flow on atrialcontraction

Reverse A wave

NORMAL

PSV>50cm/s

A WAVE REVERSAL

PSV<5cm/s

ABSENT A WAVE

UMBILICAL VEIN

• Decreased forward flow;no inc diastolic flow

• Venous pulsations

PULSATIONS

NORMAL

SIGNIFICANCE OF DOPPLER

• Not for diagnosis-positive predictive value for doppler indices is low

• Prognosis and monitoring once diagnosed

• If absent or reversed end diastolic flow in umb artery– very poor –prompt delivery

• Fetal hypoxia before acidosis (CTG- changes only if acidosis)

STEROID ADMINISTRATION

• Severe IUGR with absent EDF before 32w- no lung maturity – steroids given-improves lung maturity

• CDI- assess cardiovascular response to steroids

• Improves umbilical artery waveforms in 2/3rds

• 1/3rd-deteriorate acutely-daily monitoring is imp-needs delivery

TRANSIENT EDF PERSISTENT ARED

BASELINE

>24H

INTEGRATED FETAL TESTING

• Abnormal doppler—BPS to be done

• Timing of delivery depending only on doppler—compromise by prematurity

• BPS done if abnormal doppler --combination- safe intrauterine time

TWIN GESTATION

• Monochorionic twins-single placenta--MC complication- twin to twin transfusion syndrome;Twin embolisation syndrome

• Dichorionic twins-discordant growth

• Monoamniotic twins

TWIN TO TWIN TRANSFUSION SYNDROME:

• Predominant AV anastomoses running from donor to recipient

• Volume depletion in one twin;volume overload in the other

D R

•Suspected if polyhydramnios in recipient and oligohydramnios in donor

•To identify prognostic signs:distance b/n cord insertions, AA anastomoses, umb artery PI values

•To stage c TTTS

•To evaluate treatment

STAGING : STAGE I: donor bladder still visible

D

STAGE II:donor bladder not visibe

STAGE III:( ABNORMAL DOPPLER VALUES)

RECIPIENT TWIN:

• Inc pressure and volume overload

• RV stretches; inc end diastolic pressure

• Inc end diastolic pressure of RA

• Retrograde flow on atrial systole in DV, HV,IVC

DONOR TWIN: Volume depletion-UA changes

DONOR TWIN RECIPIENT TWIN

STAGE III:( ABNORMAL DOPPLER VALUES)

STAGE IV:HYDROPS

STAGE V:DEATH OF CO-TWIN

TO EVALUATE TREATMENT

Post amniocentesis & selective laser occlusion of AV connections-look for restoration of normal doppler indices

TWIN EMBOLISATION SYNDROME

• Death of co-twin

• Transfusion of thromboplastin rich blood or embolisation of clot &debris across vascular anastomoses

• Acute hypotensive episode-MC- Ischemic brain injury

• CDI-Normal MCA doppler within 2-3d reassures normal subsequent growth

DICHORIONIC TWINS

• Cause of discordant fetal growth

• CDI rules out placental disease- avoids frequent USG monitoring

• Differences in fetal sex, growth potential, timing of fertilisation-considered.

MONOAMNIOTIC TWINS

• identifies cord entanglement

• Common due to close insertion of cords

• Intermittent cord occlusion is detected by serial umb artery doppler

FETAL HYDROPS

• IMMUNE HYDROPS: Rh incompatibility hemolysis anemia & cardiac fail inc blood flow velocities for Oxygen inc PSV IN MCA Prevents unnecessary invasive amniocentesis or

fetal blood sampling

NON IMMUNE HYDROPS

• Causes:fetal, maternal,placental

• Monitoring for fetal welfare

• CDI- Indicates anemia, Cardiac fail

• UV pulsations or DV a wave reversal-cardiac diastolic dysfunction

• Abnormal UA &MCA waveforms

PLACENTAL & CORD ABNORMALITIES

CORD INSERTION:

Insertion if not found on placental disc-l/f velamentous insertion & marginal insertion

Marginal & velamentous cord-IUGR

MARGINAL AND VELAMENTOUS INSERTION

Vasapraevia:vessels across os

• TVS/ transperineal doppler

• to prevent inadvertent rupture of vessels in membranes at labour

• to plan caesarean

PLACENTA PERCRETA - INVASIVE PLACENTATION • >1/3rd of

Myometrium infiltrated with blood vessels-pathological

• Apparent loss of myometrial layer

• DOPPLER:Vessels in the space b/n basal plate & serosa

• TVS:Extent into bladder, pararectal & pelvic tissues

BLADDER VESSELS

SIGNIFICANCE:

• mode of delivery

• Perinatal management-By intervention radiology -uterine artery embolisation

• Goal to retain intact placenta—later sheds

SINGLE UMBILICAL ARTERY

• Umbilical cord cross section 2 Umb A

1 Umb V

Plane of transverse section of free floating loop of cord

Early diagnosis of SUA is difficult on gray scale

CDI- UAs seen around fetal bladder & cord insertion

NUCHAL CORD

• Seen as multiple echoes in nuchal region

• b/n 11-14w important to demonstrate cord in color to avoid interpretation of inc nuchal translucency

STRUCTURAL ANAMOLIES OF FETUS

OMPHALOCOELE

• Cord insertion at apex of herniated mass & course of umb vein thru defect- important

• To differentiate from gastroschisis

RENAL AGENESIS

• Oligohydramnios after 16w

• Lying down adrenal sign-discoid flattened in renal bed- mistaken

• Urachal cyst, cystic pelvic mass-mistaken for bladder

• Empty bladder may dec renal function

ROLE OF DOPPLER

• Renal arteries not seen esp on power dop

• Bladder localised by intraabd umb arteries

DIAPHRAGMATIC HERNIA

• To identify the herniated liver

• Difficult to distinguish echogenic lung lesion and herniated liver

• CDI- identifies portal vein & intrahepatic umb vein-liver

• Hydrops –compression of grave prognosis

HEART

L PORTAL V

LIVER

• Intrathoracic liver –influences prognosis

• LIVER UP-POOR PROGNOSIS

• Management differs

BRONCHOPULMONARY SEQUESTRATION:

• Abnormal lung tissue separate from rest of lung

• extralobar- congenital (intralobar-acquired-infection)

• CDI-systemic supply

• Sig- to differentiate pulmonary lesions CCAM,CDH,bronchial atresia,lobar emphysema -pulmonary blood supply-Management differs

Vessel can be occluded by USG guided laser fibre

Vessel from aorta

ANEURYSM OF VEIN OF GALEN

• single or multiple arteries/parenchymal AVM drain –single dilated midline fluid filled structure – in posterior 3rd ventricle region

• CDI- differentiates midline fluid structures- arachnoid cysts,cysts asso with agenesis of corpus callosum, porencephaly

• Heart failure

• Embolisation therapy

CDI-Confirms the diagnosis;pulsed dop-turbulent bidirectional flow, arterial flow

CONCLUSION

• Useful in screening high risk pregnancies & prevention can be given

• Diagnose conditions – differs management

• As adjunct to gray scale imaging

• Avoids unnecessary invasive procedures BASED ON SCIENTIFIC EVIDENCE OF ULTRASONICALLY

INDUCED BIOLOGICAL EFFECTS TO DATE, THERE IS NO REASON TO WITHHOLD SCANNING FOR ANY CLINICAL APPLICATION, INCLUDING ROUTINE SCANNING OF EVERY WOMAN DURING PREGNANCY-ECMUS-European committee for medical ultrasound safety