Sonographic Imaging of the Sonographic Imaging of the Female Patient with Pelvic Female Patient with Pelvic

Pain/ BleedingPain/ Bleeding

Sarah A. Stahmer MDCooper Hospital/University

Medical Center

Case PresentationCase Presentation

24 yo female presents with missed period, cramping, midline abdominal pain and spotting

VS: BP 120/80 HR 110Pelvic:

– Cervical os is closed with minimal bleeding– No CMT, adenexa symmetric

Urine hCG is +

Case presentationCase presentation

A bedside ultrasound is performed

The US reveals an IUP The patient is

discharged to home with threatened abortion precautions

LOS = 30 minutes Applies to 60% of pts

Role of Bedside SonographyRole of Bedside Sonography

Identify an IUP

Establish fetal viability

Secondary IndicationsSecondary Indications

Hemodynamic instability in a female pt

Trauma and pregnancy

Localization of IUD/foreign body

Identify sources of pelvic pain in non-

pregnant patients

Imaging: TransabdominalImaging: Transabdominal Uses a lower frequency transducer: 3.5 –5 mHz Better penetration, larger field of view It should be the initial imaging window to assess

for– Advanced IUP– Fibroids/masses– Pelvic fluid

The bladder should be full to provide an acoustic window

EndovaginalEndovaginal

Uses a higher frequency transducer: 6.0-7.5mHz Provides optimal imaging of:

– Endometrium– Myometrium– Cul-de-sac– Ovaries

A full bladder is not necessary for this approach Is usually better tolerated by patients

Scanning Protocol: TransabdominalScanning Protocol: Transabdominal

Image the patient before obtaining a urine

sample

Can fill the bladder via foley and instill 300

cc NS but…

If the bladder is empty, go directly to TV

imaging after the pelvic exam

Probe Probe SelectionSelection

“Workhorse”probe3.5 to 5.0 MHzMulti-frequency probeGood for most

cardiac/abdominal applications

UterusUterus

An oval organ located superior to the full bladder

The maximum size of the non-gravid uterus is 5-7 cm x 4-5 cm

The endometrial stripe is the opposed surfaces of the endometrial cavity

Transabdominal / Transverse viewTransabdominal / Transverse view

Right Left

Cul-de-sacCul-de-sac

Located posterior to the uterus and upper vagina

A small amount of fluid may be seen in mid cycle

A small amount of fluid in the posterior cul-de-sac may be the only sonographic finding in EP

Bladder

uterus

Probe SelectionProbe Selection

Endovaginal Probe5 to 8 mHz variable

frequency probeUp to 180 degree angle

of view

Endovaginal ExaminationEndovaginal Examination Best performed immediately following the pelvic

exam An empty bladder is required for an optimal

endovaginal (EV) exam A full bladder:

– Displaces the anatomy beyond the focal length of the transducer

– Will create artifacts that will compromise imaging

Before Performing a TV Exam:Before Performing a TV Exam:

Explain that the EV exam is better for seeing ovaries and early pregnancy

Show the patient the probeAllow her the option of inserting it herselfInform her that it is usually more

comfortable than the TA exam which requires a full bladder

The transducer probe should be covered with a

coupling gel followed by a protective probe

cover

Non-medicated/ non-lubricated condoms are

recommended as a probe cover

Patients with latex allergies will require an

alternative barrier

Air bubbles within the sheath may increase

artifacts and compromise imaging

Longitudinal viewLongitudinal view

Coronal viewCoronal view

The UterusThe Uterus

Early in the menstrual cycle – endometrium measures 4-8mm

Secretory phase– endometrium measures 7-14 mm

Post-menopausal patient– endometrial stripe usually less than 9 mm

Endometrial Stripe (ES) Endometrial Stripe (ES) MeasurementsMeasurements

In the post-partum patient, a thickened ES is suggestive of retained products of conception

In the pregnant patient, an ES measurement of < 8 mm in

the absence of an IUP is suggestive of EP

Thickening of the endometrial stripe in the post-menopausal patient with vaginal bleeding should raise suspicions for endometrial carcinoma

OvariesOvaries

Lie posterior/lateral to the uterus

Anterior to the internal iliac vessels and medial to the external iliac vessels

Identified by a ring of follicles in the periphery

OvariesOvaries

After ovulation a corpus luteal cyst may be present– Observed in approximately 50% of ovulating

females– Should not be seen beyond 72 hours into the

next cycle Small amount of fluid in the rectouterine pouch

may be seen during ovulation

Ovarian CystsOvarian Cysts

Follicular cyst (2.5 –10 cm)– Thin, round, unilocular

Functional corpus luteum cyst– Normal up to 16 weeks GA– Appears as a unilateral, unilocular 5-11 cm cyst– Appearance can be highly variable– Hemorrhage inside the cyst not uncommon

Assessment of the Pregnant PatientAssessment of the Pregnant Patient

Identify gestational sac

Demonstrate a myometrial mantle in the transverse view

Identify yolk sac and/or fetal pole

Note if there is fluid in the cul-de-sac

Gestational SacGestational Sac

Anechoic area within the uterus surrounded by two bright echogenic rings – Decidua vera (the outer ring) – Decidua capsularis (the inner ring)

This is referred to as the double decidual sac sign (DDSS)

Yolk SacYolk Sac

First embryonic structure that can be detected sonographically

Visualized approximately 5-6 weeks after the last menstrual period

Bright, ring like structure within the GSShould be readily seen when the GS sac is

greater than 10 mm (using EVS)

Fetal PoleFetal Pole

Can be first seen on EV when the fetus is approximately 2 mm in size

A thickened area adjacent to the yolk sacThe CRL is the most accurate sonographic

measurement that can be obtained during pregnancy

A Fetal Heart Beat A Fetal Heart Beat

An important prognostic indicator

The rate of spontaneous abortion is extremely low (2- 4%) after the detection of normal embryonic cardiac activity

The normal fetal heart rate in early pregnancy is 112-136

Definite IUPDefinite IUP A gestational sac

with a sonolucent center (greater than 5 mm diameter)

Surrounded by a thick, concentric, echogenic ring

GS contains a fetal pole or yolk sac, or both

Abnormal IUPAbnormal IUPA GS larger than 10-13 mm diameter(TV)

or 20mm (TA) without a yolk sac

A GS larger than 18 mm (TV) or 25mm (TA) without a fetal pole

A definite fetal pole without cardiac activity after 7 wks GA

Empty gestational sacEmpty gestational sac

Fetal demiseFetal demise

Sonographic Spectrum of EPSonographic Spectrum of EP

Ruptured ectopic pregnancy

Definite ectopic pregnancy

Extrauterine empty gestational sac

Adenexal mass

Pseudogestational sac

Empty uterus

Definite Ectopic Pregnancy Definite Ectopic Pregnancy

A thick, brightly echogenic, ring-like structure located outside the uterus with a gestational sac containing an obvious fetal pole, yolk sac or both.

Ruptured Ectopic PregnancyRuptured Ectopic Pregnancy

Free fluid or blood in the cul-de-sac or the intra-peritoneal gutters (hemoperitoneum)

This finding and a positive pregnancy test essentially makes the diagnosis!

Clot/fluidclot

Extrauterine Gestational SacExtrauterine Gestational Sac

Extra-uterine mass containing a thick, brightly echogenic ring surrounding an anechoic area

Brightly echogenic appearance may be helpful

Tubal ring

Adenexal MassAdenexal Mass

Pseudogestational SacPseudogestational Sac

Stimulation of the endometrium Decidual breakdown results in a central

anechoic areaCan be confused with “early IUP”Does not have double decidual sac signCorrelation with ß hCG helpful

Pseudogestational sac

Ectopic

Interstitial Ectopic PregnancyInterstitial Ectopic Pregnancy

Implantation near the insertion of the fallopian tubes

Highly vascular areaSuspect when GS is not centrally locatedDemonstration of endometrial mantle is

critical to the diagnosis

Empty UterusEmpty Uterus

Correlation with ßhCG critical

ßhCG >discriminatory zone and empty uterus is EP until proven otherwise

Discriminatory HCG ZoneDiscriminatory HCG Zone

5 weeks since last normal LMP– ß hCG value = 1800 mIU

TAS landmarks– 5 to 8-mm GS

TVS landmarks– 5 to 8-mm GS– With or w/o yolk sac

Discriminatory HCG ZoneDiscriminatory HCG Zone

6 weeks since last normal LMP– ß hCG = 7200

TAS landmarks– Yolk sac

TVS landmarks– Yolk sac and

embryo– Possibly FHM

Discriminatory HCG ZoneDiscriminatory HCG Zone

7 weeks since last normal LMP– ß hCG = 21,000

TAS landmarks– 5 to 10-mm embryo

with FHM TVS landmarks

– 5 to 10 mm embryo with FHM

Rule - in IUP ProtocolRule - in IUP Protocol

Clinically stable females with: Clinically stable females with:

(1)(1) Lower abdominal painLower abdominal pain

(2)(2) Vaginal bleedingVaginal bleeding

(3)(3) OrthostasisOrthostasis

(4)(4) Or risk factors for EPOr risk factors for EP

Positive urine preg Ultrasound

Rule - in IUP ProtocolRule - in IUP Protocol

Ultrasound

Definite IUP

Can DC to home with f/u

Definite EP

OB consultation

Rule - in IUP ProtocolRule - in IUP Protocol

Ultrasound

No IUP but…

+ Adenexal tenderness or CMT

Free fluid in the cul de sac

And/or hCG > discriminatory zone

OB Consultation

Rule - in IUP ProtocolRule - in IUP Protocol

Ultrasound

No IUP

Benign exam

ßhCG > discriminatory zone

DC to home

F/u exam and ßhCG w/in 48 hrs

Rule-In IUP ProtocolRule-In IUP Protocol

Sixty percent of patients will have IUP– “Rules out” ectopic pregnancy by “ruling

in” IUPWhat about heterotopic pregnancy?

– Increased in patients undergoing ovulation induction consult OB

– Risk is 1/30,000 in non-induced pregancy

PitfallsPitfalls

Diagnosing intrauterine fluid collections as “early” IUP

Low hCG does not mean “low risk” for EPFailure to determine the exact location of a

gestational sac Cul-de-sac fluid may be the only sonographic

finding of extrauterine pregnancy