Ectopic Pregnancy

Ectopic Pregnancy

Mindy M. Horrow, MD, FACR, FSRU

Director of Body Imaging

Einstein Medical Center

Professor of Radiology

December 3, 2012

Clinical Features

Incidence: 1.5 -2% pregnancies, 15% all maternaldeaths and 80% of 1st trimester deaths

–Incidence in 1948 of 0.37%

-hCG – often rises at a slower rate and/or mayplateau, but 21% of ectopics have normal rising levels

Risk related to tubal abnormalities: previous EP, tubalsurgery, PID, IUD, increased maternal age and parity,prior C-section

Classical findings < 50%

–Pain, bleeding, adnexal mass

Lin, etal Radiographics 2008;28:1661

Diagnosis

★★Transvaginal ultrasound★★

No reliable serum markers

Screening not thought to be cost effective

–With possible exception of prior tubal ligation

Progesterone: primarily an indication of viabilityrather than location.

–> 25 ng/ml has 98% association with normal IUP

–< 5 ng/ml indicates non-viable pregnancy regardless oflocation

–Most ectopic pregnancies have progesterone levelsbetween these two concentrations, limiting the usefulnessof this measurement

Sowter, Curr Opin Ob Gyn 2004;16:289

Location

Fallopian tube

–Ampullary- isthmic - 95%

–Interstitial (cornual) – 2 -3% (intramural portion oftube where it passesthrough wall of uterus toenter endometrial canal)

Extra-tubal: RARE

–Abdominal, cervical,uterine scar, ovarian

Sonography: Technique

Initial transabdominal view to look foradvanced IUP, large mass or largeamount of fluid/blood

Transvaginal

± Doppler

Sonography of Ectopic Pregnancy

Endometrium

Adnexa

Free fluid

Doppler

Endometrium

Pseudosac-

–Fluid collection, often blood in endometrial cavity

–Occurs in up to 20%

Decidual cysts

Appearance and thickness of endometrium: not veryuseful

–EMS usually thinner in patients with EP compared to normalIUP and spontaneous AB, because of lower -HCG levels

–Thin, tri-laminar EMS is specific (85 – 94%), but not verysensitive (10-38%) for EP

Hammoud, AJOG 2005;192:1370

Wachsberg J Clin US 1998;26:199

Examples of pseudosacs

Usually multiple, located at endometrialmyometrial junction, thin walled comparedto gestational sac

Examples of decidual cysts

Adnexa

Live ectopic pregnancy

Non-viable ectopic pregnancy

Tubal ring

Hematosalpinx: “mass” or“blob” separate from ovary

Study of 200 patients with surgically provenectopic pregnancy and pre-operativetransvaginal scan

57.9 % inhomogeneous blob or mass

13.2 % with embryo  cardiac activity

20.4 % hyperechoic ring in adnexa

7.2 % no IUP or ectopic visualized

1.3% heterotopic pregnancies

Sen 90.9%, Spe 99.9%, PPV 93.5%, NPV 99.8% for TVUS todetect the ectopic pregnancy

Condous Human Reprod2005;20:1404

Highly dependent on quality of scanning

Small tubal rings

Transvaginal more limited than transabdominal imaging

If scanning TA, try higher frequency transducer

Examples of hematosalpinges

Hematosalpinx with identifiable tubal ring

Hematosalpinx containing live ectopic

Tubal “Ring” vs. CorpusLuteum

Corpus luteal cyst is eccentric with rim of ovariantissue

Tubal ring has concentric echogenic rim and is oftensurrounded by a hematosalpinx

Echogenicity of tubal ring greater than ovarywhereas corpus luteal cyst is equal to or lessechogenic.

When a corpus luteum was visualized,  80% hadipsilateral ectopic pregnancy

Anechoic or complex ovarian cyst most likely acorpus luteum because ovarian ectopics are < 1%of all ectopic pregnancies

Frates, JUM 2001;20:27

Condous, Human Reprod 2005;20:1404

Corpus luteum versus ectopic tubal ring

Right Interstitial (Cornual) Ectopic

Interstitial Ectopic Pregnancy

Because of intramural location, rupture may belater than usual EP, but cause massivehemorrhage with higher mortality.

Myometrial thinning and sac eccentricity notalways reliable

“Interstitial line sign” – a thin echogenic linefrom EMS to cornual sac or echogenic massseen in 92%

Treatment: laparotomy with cornual resection,methotrexate (local or systemic)

Ackerman, Rad 1993;189:83

Trans-abdominal view

Trans-vaginal views

Non-viable interstitialectopic pregnancy

Free Fluid

Pelvic and abdominal

If complex, indicates hemoperitoneum

Presence or absence of fluid does not necessarilyindicate rupture (Significant bleeding can occurfrom fimbriated end of tube, without rupture)

Transvaginal sonography has virtually replacedculdocentesis

Small amounts of simple fluid are physiologic

Frates, Rad 1994;191:769

Ruptured ectopic, clotted bloodobscures uterine borders

Ruptured ectopic, large amount of bloodbetter appreciated transabdominally

If clinically unstable, can terminate examwithout demonstrating ectopic pregnancy

Sagittal Transverse

R Adnexa: Transverse Sagittal

Ruptured Right Ectopic Pregnancy

Color Doppler helps locate EP

-HCG 890

Images of “Mass” in cul-de-sac

At surgery fallopian tube was intact,with EP aborted into cul-de-sac

Acute pain, - HCG 22

Ruptured left ectopic pregnancy

Sent by ER and OB to confirmdemise

Where is uterus?

Ruptured ectopicpregnancy

42 yo with acute pain and hypotension

Acutely bleeding, ruptured EP

Doppler Analysis

Low impedance placental(trophoblastic) flow

–Extrauterine

–Corpus luteal

Bizarre waveforms: very high andvery low resistive indices

Use of color Doppler slightlyincreases ability to detect the EP

Atri. JUM 2003;22:1181

Left-Transverse

Left Sag

Left ectopic pregnancy

Left corpus luteum

Similar low resistance flow in corpusluteum and ectopic pregnancy

7mm “donut” separate

from left ovary

L corpus luteal flow

Flow in “mass” near ovary

7mm left ectopic

Color Doppler aids

visualization

Value of Doppler

Presence of extra-uterine trophoblastic flowhas sensitivity of 48% for EP

Doppler has lower sensitivity and NPV than2D imaging.

May have benefit for directing therapy. Ifvascular, surgery or medical therapyindicated. If avascular with dropping HCGlevels, ectopic tissue is being aborted.

Hypervascular ring of low resistance flow more likelyindicates corpus luteum than ectopic pregnancy

Management of Ectopic Pregnancy

Surgery- usually laparoscopy with eithersalpingotomy or salpingectomy

Spontaneous resolution- more common forstable patients with declining -HCG.Success rates near 70% in select group

Medical - methotrexate

Yao, Fertil Steril 1997;67:421

Methotrexate Therapy

Systemic vs. local

 hCG levels at presentation predictoutcomes:  92.5% success if  hCG < 4000IU/l

Criteria:

1. Stable patient

2. Growing EP ( -hCG)

3. No findings of rupture

4. EP < 3.5 cm

Stovall, Am J Obstet Gyn 1993

Tawfiq, Fertl Steril 2000; 74:877

Gamzu, Fertl Steril 2002; 77:761

Methotrexate vs. Surgery

Saraj, etal Ob Gynec 1998; 92:989

–78% success single dose methotrexate

–92% success laparoscopic surgery

Sowter, etal BJOG 2001; 108:192

–65% success single dose methotrexate

–93% success laparoscopic surgery

Sowter, etal BJOG 2001; 108:204

–Medical treatment associated with reduced directand indirect costs although at hCG levels > 1500IU/l benefits were lost due to need for prolongedfollow-up and surgical intervention

Methotrexate Therapy

Sonography

–Initially may increase in size or vascularity, free fluid.

–May take as long as 5 months for EPresolution

–Rupture may occur, causing pelvic pain and ahemorrhagic mass on sonography.

Atri et al, Radiology 1993

Pregnant patient with right sided pain and prior left

Salpingectomy for ectopic pregnancy

Dx: Right Ectopic

Pregnancy (2/23)

Treatment: Methotrexate

3/2 tubal ring visible 3/16 smaller

6 months later- hysterosalpingogram

Free spill right tube

Increasing size of tubal “mass”with methotrexate therapy

Right ectopic pregnancy treated with methotrexate on6-6-07, returns with pain on 7-3-07

Increased size of ectopic pregnancy, leakingblood, required surgery

Failed methotrexate

Other Issues

Unusually located ectopic pregnancy

Uterine and adnexal abnormalities

Ectopic pregnancy mimics

Advanced ectopic pregnancy mistaken forintrauterine pregnancy

Chronic Ectopic Pregnancy

Heterotopic pregnancy: high risk patients (IVF)or IUP with suspicious mass

R OV

Mono-mono twin ectopic pregnancy

Diamniotic dichorionicTwin ectopic pregnancy

Stable pregnant patient with slight bleeding

Chronic Ruptured EctopicPregnancy

Had D&C after “miscarriage”, persistent spotting, -HCGstill positive, left pelvic pain

Chronic EctopicPregnancy

Chronic Ectopic Pregnancy

Repeated small ruptures cause hematoceleconsisting of clots, gestational tissue, adhesions

Surgery often difficult 2° adhesions

Patients often mildly symptomatic, sometimes withlonger duration of symptoms

Study of 305 EPS, found 20.3% (62) cases whichfit this description, 5 with negative -HCG (Uqur)

Bedi Eur J Radiol 1987;7:46

Uqur Aust NZ J Ob Gyn 1996;36:186

ER scan shows “ectopic pregnancy”

6.5 weeks IUP displacedby large fibroid

Live pregnancy growingin C-section scar

2 days later after systemic methotrexate

Surgery required to treat ectopicpregnancy

Caesarean Scar Implantation

Appears to be increasing in incidence

–5% of ectopic pregnancies in women with at least oneprior Caesarian section

History of painless vaginal bleeding and priorcaesarian section(s)

Pregnancy cannot continue because trophoblast willextend beyond uterus to bladder resulting incatastrophic hemorrhage and need for hysterectomy

May have similar appearance to an abortinggestational sac in the lower uterine segment, checkvascularity.

Jurkovic, US Ob Gynec 2003;21:220

Caesarean Scar Implantation

Gestation is completely surrounded by myometriumand fibrous scar and separate from endometrial cavityor fallopian tube

Probable mechanism is invasion of myometriumthrough a microscopic tract. Similar to interstitialpregnancy.

US Findings: empty uterine cavity, empty cervicalcanal, sac in anterior lower uterus

No consensus on treatment: Can try medical therapy,but only surgery will allow removal of the pregnancyand repair of the defect

Fylstra, Obstet Gyn Survey 2002;57:537

Pregnant patient with

Bleeding, 4-30

Interpreted asspontaneous abortionin progress

Still bleeding 6-06

Retained products ofconception of scar ectopic

Abortion in progress or ectopic pregnancy?

Patient A

Patient B

Live Cervical Ectopic Pregnancy

Patient B 10 days later

Cervical Ectopic Pregnancy

Occurs in 0.15% of all ectopic pregnancies

If sac is within endocervical canal and embryodemonstrates cardiac activity and/or trophoblasticflow, more likely a cervical ectopic than an abortionin progress

Surgery may lead to significant hemorrhage soconservative treatments include: US guided localinjection methotrexate or KCl or preoperative uterineartery embolization before dilation and evacuation

Levine Radiology 2007;245:385