imaging of abnormal placental implantation: a patient with placenta
TRANSCRIPT
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Imaging of Abnormal Placental Implantation: A Patient with Placenta Percreta
Sonya Trinh, Harvard Medical School Year IIIGillian Lieberman, MD
June 2009
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Agenda
• Patient L.S.• Menu of Tests• Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation• Differential Diagnosis • Conclusions
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Agenda: Patient L.S.
• Patient L.S.• Menu of Tests• Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation• Differential Diagnosis• Conclusions
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Patient L.S.: History of Present Illness
CC: Placenta previa with vaginal bleeding
HPI:• 32 year old female G3P2 at 18 weeks GA • Presents with episode of bright red vaginal blood
• Bleeding has subsided• Denies contractions, cramping, pain
• Bleeding episode at 5 weeks GA• Diagnosed with placenta previa by US• No bleeding since first episode
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Patient L.S.: Past Obstetrical History
Past Obstetrical History:• Cesarean section
– Arrest of descent• Cesarean section
– Repeat, twin intrauterine pregnancy
Reason for Imaging: Narrow differential diagnosis• Placenta accreta• Placenta increta• Placenta percreta
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Agenda: Menu of Tests
• Patient L.S. • Menu of Tests• Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation• Differential Diagnosis• Conclusions
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Menu of Tests: Obstetrical Imaging in 2nd and 3rd Trimester
Preferred imaging modalities:• Ultrasound (US)• Magnetic Resonance Imaging (MRI)
– Abdominal MRI, -contrast
Lesser used studies:• Radiograph• Computed Tomography (CT)
– Abdominal CT, -contrast
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Effects of Ionizing Radiation
Increased risk:• Miscarriage• Congenital anomalies• Genetic disease• Growth restriction• Developmental disorders
When imaging modality necessary:• Radiograph
– Wear lead apron to minimize fetal exposure– Fast film/screen combination or digital radiography
• Computed Tomography– Narrow collimation and wide pitch– Patient moves through scanner at faster rate
Brent, 2009
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Menu of Tests: Ultrasound
Description:• Transducer emits and receives sound waves• Spatial distribution determined by time for sound waves to return
Advantages:• No biologic effects documented• No contraindications
Limitations:• Difficult to image fetus in obese patients• Operator dependent
– Image quality depends on sonographer skill
Lieberman, Gillian. http://eradiology.bidmc.harvard.edu/primarycare/radiologicmenu.html
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Menu of Tests: Magnetic Resonance Imaging
Description:• Magnets and radiowaves causes alignment of hydrogen protons• Different electronic environments lead to different signals
Advantages:• No ionizing radiation• No reported harmful effects • Excellent images of soft tissue
Limitations:• Avoid in first trimester
– No experience with safety during organogenesis• Potential safety concerns
– Induce local electric fields and currents– Radiofrequency radiation heats tissue– Projection of metal objects
• Gadolinium contrast not recommended
Lieberman, Gillian. http://eradiology.bidmc.harvard.edu/primarycare/radiologicmenu.htmlShellock et al., 2004
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Agenda: Anatomy of Female Pelvis and Placenta
• Patient L.S.• Menu of Tests• Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation• Differential Diagnosis• Conclusions
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Anatomy of Female Pelvis: Sagittal View
http://www.rush.edu/rumc/page-1098987343902.html
Anterior Posterior
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Anatomy of Female Pelvis: Placenta
http://www.rush.edu/rumc/page-1098987343902.html
Anterior Posterior
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Anatomy of the Placenta: Close-Up
http://utdol.com/online/content/image.do;jsessionid=F77F02EF28252E1638A20B402D73CB4E.1103?imageKey=obst_pix/placen4.htm&title=Placental%20vasculaturehttp://www.rush.edu/rumc/page-1098987343902.html
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Anatomy of the Placenta: Maternal Surface
http://utdol.com/online/content/image.do;jsessionid=F77F02EF28252E1638A20B402D73CB4E.1103?imageKey=obst_pix/placen4.htm&title=Placental%20vasculaturehttp://www.rush.edu/rumc/page-1098987343902.html
Myometrium
Endometrium
Decidua•Acts as barrier to invasion by fetal chorionic villi
Myometrium EndometriumDecidua
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Anatomy of the Placenta: Fetal Surface
http://utdol.com/online/content/image.do;jsessionid=F77F02EF28252E1638A20B402D73CB4E.1103?imageKey=obst_pix/placen4.htm&title=Placental%20vasculaturehttp://www.rush.edu/rumc/page-1098987343902.html
Chorionic villi
Umbilical cord
Chorionic villi•Can invade past decidua into maternal surface
Umbilical cord
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Anatomy of the Placenta: Maternal and Fetal Surface
http://utdol.com/online/content/image.do;jsessionid=F77F02EF28252E1638A20B402D73CB4E.1103?imageKey=obst_pix/placen4.htm&title=Placental%20vasculaturehttp://www.rush.edu/rumc/page-1098987343902.html
Myometrium
Endometrium
Decidua
Chorionic villi
Umbilical cord
Myometrium EndometriumDecidua
Chorionic villi
Umbilical cord
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Agenda: Abnormal Placental Implantation
• Patient L.S.• Menu of Tests • Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation• Differential Diagnosis• Conclusions
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Placenta Previa: Definition and Types
Definition:• Placenta overlies or lies
proximal to internal cervical os
Types:A. MarginalB. PartialC. Complete
http://myhealth.ucsd.edu/library/healthguide/en-us/support/topic.asp?hwid=aa154120http://www.aafp.org/afp/AFPprinter/20070415/1199.htmlMagann et al., 2007
A.
B.
C.
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Placenta Previa: Clinical Facts
http://myhealth.ucsd.edu/library/healthguide/en-us/support/topic.asp?hwid=aa154120http://www.aafp.org/afp/AFPprinter/20070415/1199.htmlFaiz et al., 2003Cotton et al., 1980
A.
B.
C.
Risk factors:•Endometrial scarring•Cesarean delivery•Increasing parity•Increasing maternal age•Prior curettage for abortion
Clinical presentation:•Painless vaginal bleeding after 20 weeks•Can present with uterine contractions
Diagnosis:•Straightforward by US
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Placenta Accreta: Definition and Types
Definition:• Chorionic villi attach to myometrium• Villi invade past maternal decidua layer
Types• Accreta
– Attach to myometrium• Increta
– Invade into myometrium• Percreta
– Invade past uterine serosa into organs
http://embryology.med.unsw.edu.au/Notes/images/placenta/anchoring-villi2.jpghttp://embryology.med.unsw.edu.au/Notes/placenta2.htmMiller et al., 1997
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Placenta Accreta: Clinical Facts
Risk Factors:• Previous uterine surgery• Prior cesarean delivery
Clinical Manifestations:• Profuse hemorrhage after delivery• Inability to separate placenta from uterus• Life-threatening
Diagnosis:• US and MRI• No imaging modality determines diagnosis with
absolute accuracy– US=Sensitivity 0.8, Specificity 0.95– MRI=Sensitivity 0.88, Specificity 1.00
http://embryology.med.unsw.edu.au/Notes/images/placenta/anchoring-villi2.jpghttp://embryology.med.unsw.edu.au/Notes/placenta2.htmMiller et al., 1997Warshak et al., 2006
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Agenda: Approach to OB US
• Patient L.S.• Menu of Tests• Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation
– Approach to Obstetrical Ultrasound• Differential Diagnosis• Conclusions
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Approach to Obstetrical Ultrasound EvaluationCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Check relevant structures:•Anterior abdominal wall•Uterus
•Myometrium•Placenta•Amniotic Fluid•Fetus•Cervix•Ovaries•Bladder
Placenta Location:•Anterior vs. Posterior uterine wall•Cervical status
Placenta previa?
Placenta texture:•Homogeneous vs. heterogeneous•Distinct myometrial surface?
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Approach to OB US Evaluation: Practice on Companion Patient 1, Normal Pelvic Anatomy
Companion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Analyzing ultrasound images can be difficult, especially when the orientation of the images are not apparent.
Now that we have learned an approach to obstetrical ultrasound evaluation, let’s practice on Companion Patient 1 who has normal pelvic anatomy during pregnancy.
Refer back to these normal images and the color coding of the anatomical structures when examining the US images for our patient L.S.
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Companion Patient 1: Orientation of Sagittal View on US Companion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
In these ultrasound images:
•The transducer was placed on anterior abdominal wall
•For sagittal views, patient’s legs are always to the right
Anterior
Posterior
Caudal
http://www.rush.edu/rumc/page-1098987343902.html
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Companion Patient 1: Location of Cross-Sectional ViewsCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
MU
Anterior
Posterior
Caudal
CX
For these sagittal views, the transducer was placed in the following locations:
•Mid-uterus (MU)
•Cervix (CX)
http://www.rush.edu/rumc/page-1098987343902.html
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Companion Patient 1: Normal Anterior Abdominal WallCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
http://www.rush.edu/rumc/page-1098987343902.html
Anterior abdominal wall
Hyperechoic structure with striations
Most anterior
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Companion Patient 1: Normal UterusCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
http://www.rush.edu/rumc/page-1098987343902.html
Uterus, Myometrium
Hypoechoic structure under anterior abdominal wall
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Companion Patient 1: Normal PlacentaCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
PlacentaHomogeneous hypoechoic structure lining uterine wall
Usually located on anterior uterine wall
http://www.rush.edu/rumc/page-1098987343902.html
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*
* *
* *
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Companion Patient 1: Normal Amniotic FluidCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
Amniotic FluidAnechoic area in uterine cavity, surrounding fetus
http://www.rush.edu/rumc/page-1098987343902.html
**
* * *
*
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Companion Patient 1: Normal FetusCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
FetusIn uterine cavity, surrounded by anechoic amniotic fluid
http://www.rush.edu/rumc/page-1098987343902.html
* **
**
*
*
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Companion Patient 1: Normal CervixCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
CervixAnechoic
Linear
Posterior to bladder
http://www.rush.edu/rumc/page-1098987343902.html
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Companion Patient 1: Normal BladderCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
BladderAnechoic
Inferior to uterus
http://www.rush.edu/rumc/page-1098987343902.html
*
**
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Companion Patient 1: Normal Pelvic Anatomy SummaryCompanion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
Anterior
Posterior
Caudal
Anterior abdominal wall
Uterus, Myometrium
Placenta
Amniotic fluid
Fetus
Cervix
Bladderhttp://www.rush.edu/rumc/page-1098987343902.html
*
**
* **
**
** * *
* * *
** * *
*
* *
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Companion Patient 1: Obstetrical US Evaluation Companion Patient 1, Normal
Transabdominal US, Mid Uterus, Sagittal View
Transabdominal US, Cervix, Sagittal ViewPACS, BIDMC
* * *
* * *
Now that we have reviewed the normal female pelvic anatomy on US, let’s make some impressions:
Placenta Location:•On anterior uterine wall•Placenta does not extend to internal cervical os
•No evidence of previa
Placental texture:•Homogeneous•Distinct interface between uterus and placenta
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Approach to Ultrasound Evaluation: Fetus
Number of gestations• Single or multiple
Position• Cephalic or breech
Fetal Heart Rate• Normal is >100 bpm
Dating by fetal measurements• Head size
– Biparietal diameter (BPD)– Head circumference (HC)
• Abdominal circumference (AC)• Femur length (FL)
Amniotic fluid volume
Umbilical cord structure
Morphologic AbnormalitiesTransabdominal US, Sagittal View, BreechPACS, BIDMC
Our Patient L.S.
Transabdominal US, Axial View, Heart
Transabdominal US, Sagittal View, Fetal HR Transabdominal US, Sagittal View, BPD, HC
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Agenda: Film Interpretation
• Patient L.S. • Menu of Tests• Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation
– Patient MV• Differential Diagnosis• Conclusions
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Our Patient L.S.: Placenta Previa on US
Transabdominal US, Sagittal View, Cervix
Transabdominal US, Sagittal View, PlacentaPACS, BIDMC
* **
Film Findings:1. Placenta located on
anterior uterine wall
2. Placenta extends overinternal cervical os
Impression 1:Placenta previa
Our Patient L.S.
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Our Patient L.S.: Placenta Previa on US, Labeled
Transabdominal US, Sagittal View, Cervix
Transabdominal US, Sagittal View, PlacentaPACS, BIDMC
* **
Film Findings:1. Placenta located on
anterior uterine wall
2. Placenta extends overinternal cervical os
Impression 1:Placenta previa
Our Patient L.S.
* *
*
* **
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Our Patient L.S.: Placenta Previa on US, Labeled
Transabdominal US, Sagittal View, Cervix
Transabdominal US, Sagittal View, PlacentaPACS, BIDMC
* **
Film Findings:1. Placenta located on
anterior uterine wall
2. Placenta extends overinternal cervical os
Impression 1:Placenta previa
Our Patient L.S.
* *
*
* **
* *
http://myhealth.ucsd.edu/library/healthguide/en-us/support/topic.asp?hwid=aa154120
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Our Patient L.S.: Increased Vascularity in Myometrium with Linear-Array US
Linear-array transducer• Fine image resolution• Sound waves cannot penetrate as deep
Transabdominal US, Low Uterus, Sagittal View Transabdominal US Doppler, Low Uterus, Sagittal ViewPACS, BIDMC
Our Patient L.S.
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Our Patient L.S.: Increased Vascularity in Myometrium on Linear-Array US, Findings
Film Findings:1. Loss of the myometrial and placental interface anteriorly2. Increased vascularity extending into myometrium
Transabdominal US, Low Uterus, Sagittal View Transabdominal US Doppler, Low Uterus, Sagittal ViewPACS, BIDMC
Our Patient L.S.
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Our Patient L.S.: Increased Vascularity in Myometrium on Linear-Array US, Labeled
Film Findings:1. Loss of the myometrial and placental interface anteriorly2. Increased vascularity extending into myometrium
Transabdominal US, Low Uterus, Sagittal View Transabdominal US Doppler, Low Uterus, Sagittal ViewPACS, BIDMC
Our Patient L.S.
* * *
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Our Patient L.S.: Increased Vascularity in Bladder Wall on US, Labeled
Film Findings:1. Hypoechoic tubular structure representing placental vein extending
into myometrium
2. Increased vascularity in bladder wall
Our Patient L.S.
Transvaginal US, Bladder, Sagittal View Transvaginal US Doppler, Bladder, Sagittal ViewPACS, BIDMC
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Our Patient L.S.: Increased Vascularity in in Bladder Wall on US, Labeled
Film Findings:1. Hypoechoic tubular structure representing placental vein extending
into myometrium
2. Increased vascularity in bladder wall
Our Patient L.S.
Transvaginal US, Bladder, Sagittal View Transvaginal US Doppler, Bladder, Sagittal ViewPACS, BIDMC
* **
*
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Our Patient L.S.: Increased Vascularity in Bladder Wall on US, Labeled
Impression 2: Differential DiagnosisPlacenta accretaPlacenta incretaPlacenta percreta
Our Patient L.S.
Transvaginal US, Bladder, Sagittal View Transvaginal US Doppler, Bladder, Sagittal ViewPACS, BIDMC
* **
*
http://embryology.med.unsw.edu.au/Notes/placenta2.htm
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Our Patient L.S.: Fetal Examination on US
Number of gestations•Single
Position•Breech
Fetal Heart Rate•Normal 154 bpm
Dating by fetal measurements•BPD=3.45 cm•HC=13.63 cm•Age by US=17 weeks
Amniotic fluid volume•Normal
Umbilical cord structure•Normal
Morphologic Abnormalities•None
Our Patient L.S.
Transabdominal US, Mid Uterus, Sagittal View, Breech
Transabdominal US, Fetal Heart Rate
Transabdominal US, Upper Uterus, Transverse ViewPACS, BIDMC
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Our Patient L.S.: Follow-Up
Impression:1. Placenta previa2. Placenta accreta, possible placenta percreta3. Normal survey of fetus
Recommendations:• Follow-up with US and MRI closer to delivery
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Our Patient L.S.: Loss of Placental Myometrial Interface on F/U US
Film Findings:1. Loss of normal placental myometrial interface anteriorly2. Increased vascularity extending to bladder wallImpression:• Suggestive of Placenta Percreta
Transabdominal US, Low uterus, Transverse View Transabdominal US Color Doppler, Low uterus, Transverse View
PACS, BIDMC
Our Patient L.S.
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Our Patient L.S.: Loss of Placental Myometrial Interface on F/U US, Labeled
Film Findings:1. Loss of normal placental myometrial interface anteriorly2. Increased vascularity extending to bladder wallImpression:• Suggestive of Placenta Percreta
Transabdominal US, Low uterus, Transverse View Transabdominal US Color Doppler, Low uterus, Transverse View
PACS, BIDMC
Our Patient L.S.
* *
* ** *
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Our Patient L.S.: Increased Vascularity in Bladder Wall on F/U US
Film Findings:1. Irregular superior bladder wall2. Increased vascularity in bladder wallImpression:• Suggestive of Placenta Percreta
Transvaginal US, Low Uterus, Transverse View Transvaginal US Color Doppler, Low Uterus, Transverse View
Our Patient L.S.
PACS, BIDMC
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Our Patient L.S.: Increased Vascularity in Bladder Wall on F/U US, Labeled
Film Findings:1. Irregular superior bladder wall2. Increased vascularity in bladder wallImpression:• Suggestive of Placenta Percreta
Transvaginal US, Low Uterus, Transverse View Transvaginal US Color Doppler, Low Uterus, Transverse View
Our Patient L.S.
PACS, BIDMC
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Our Patient L.S.: F/U Fetal US Examination
Film Findings:• Fetal Heart Rate
– Normal 158 bpm• Normal growth
– BPD=7.01 cm– HC=9.08 cm– Age by US=28 weeks, 1 day
PACS, BIDMC
Transabdominal US, Axial View, Fetal Heart Rate Transabdominal US, Axial View, BPD, HC
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Approach to Obstetrical MRI Evaluation
• Check relevant structures:– Anterior abdominal wall– Uterus
• Myometrium– Placenta– Amniotic Fluid– Fetus– Cervix– Ovaries– Bladder
• Placenta Location:– Anterior vs. Posterior uterine wall– Cervical status
• Placenta previa?
• Placenta texture:– Homogeneous vs. heterogeneous– Distinct myometrial surface?
Companion Patient 2, Normal
Abdominal T2 Weighted MRI, Sagittal ViewPACS, BIDMC
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Approach to MRI Evaluation: Fetus
Number of gestations• Single or multiple
Position• Cephalic or breech
Morphologic Abnormalities• Better soft tissue contrast
• Head, face, heart, outflow tracts, stomach, kidneys, cord insertion site, bladder, spine, extremities
• Congenital abnormalities
Companion Patient 2, Normal
Abdominal T2 Weighted MRI, Coronal ViewPACS, BIDMC
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Our Patient L.S.: Marginal Placenta on MRI
Film Findings:1. Placenta location
• Low anterior position• Extends more posterior on left
2. Placenta extension• Margin of the internal cervical os• But does NOT cover os
Impression 1:Marginal Placenta
Our Patient L.S.
Abdominal T2 Weighted MRI, Coronal View
PACS, BIDMC
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Our Patient L.S.: Marginal Placenta on MRI, Labeled
Film Findings:1. Placenta location
• Low anterior position• Extends more posterior on left
2. Placenta extension• Margin of the internal cervical os• But does NOT cover os
Impression 1:Marginal Placenta
Our Patient L.S.
Abdominal T2 Weighted MRI, Coronal View
PACS, BIDMC
***
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Companion Patient 2: Normal Interface between Myometrium and Placenta on MRI
Companion Patient 2, Normal
Abdominal T2 Weighted MRI, Sagittal View
PACS, BIDMC
Before examining the placenta on MRI in our patient L.S., let’s first examine the placenta in a normal pregnancy.
When examining a normal pregnancy on MRI,there is a distinct interface between the placenta and uterus.
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Our Patient L.S.: Loss of Interface between Myometrium and Placenta on MRI
Film Findings:1. Anterior loss of normal myometrium overlying the placenta2. Prominent intramural vessels in anterior wall of uterus
Companion Patient 2, NormalOur Patient L.S.
Abdominal T2 Weighted MRI, Sagittal View Abdominal T2 Weighted MRI, Sagittal View
PACS, BIDMC
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Our Patient L.S.: Loss of Interface between Myometrium and Placenta on MRI, Labeled
Film Findings:1. Anterior loss of normal myometrium overlying the placenta2. Prominent intramural vessels in anterior wall of uterus
Companion Patient 2, NormalOur Patient L.S.
Abdominal T2 Weighted MRI, Sagittal View Abdominal T2 Weighted MRI, Sagittal View
PACS, BIDMC
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Our Patient L.S.: Placenta Extending to Roof of Bladder on MRI
Film Findings:1. Loss of normal myometrial signal at lower uterine segment2. Placental tissue extends to roof of the bladder3. Vessels contiguous with placenta extend into bladder roof
Abdominal T2 Weighted MRI, Sagittal View Abdominal T2 Weighted MRI, Sagittal View
Our Patient L.S. Our Patient L.S.
PACS, BIDMC
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Our Patient L.S.: Placenta Extending to Roof of Bladder on MRI, Labeled
Film Findings:1. Loss of normal myometrial signal at lower uterine segment2. Placental tissue extends to roof of the bladder3. Vessels contiguous with placenta extend into bladder roof
Abdominal T2 Weighted MRI, Sagittal View Abdominal T2 Weighted MRI, Sagittal View
Our Patient L.S. Our Patient L.S.
PACS, BIDMC
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Our Patient L.S.: Placenta Extending to Roof of Bladder on MRI, Labeled
Impression 2:Placenta percreta involving inferior aspect of lower uterine
segment, tissue extends into roof of bladder
Abdominal T2 Weighted MRI, Sagittal View Abdominal T2 Weighted MRI, Sagittal View
Our Patient L.S. Our Patient L.S.
PACS, BIDMC
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Companion Patient 2: Normal Fetal Examination on MRI
Abdominal T2 Weighted MRI, Coronal View
Companion Patient 2, Normal
PACS, BIDMC
Before examining the fetusin our Patient L.S. on MRI, let’s first examinethe fetus in a normal pregnancy.
In a normal pregnancy, the fetus is usually in a cephalic position, with the head pointing towards the cervix.
66
Our Patient L.S.: Fetal Examination on MRI
Film Findings:1. No gross fetal abnormality2. Footling breech
Abdominal T2 Weighted MRI, Coronal ViewAbdominal T2 Weighted MRI, Coronal View
Companion Patient 2, NormalOur Patient L.S.
PACS, BIDMC
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Our Patient L.S.: Fetal Examination on MRI, Labeled
Film Findings:1. No gross fetal abnormality2. Footling breech
Abdominal T2 Weighted MRI, Coronal ViewAbdominal T2 Weighted MRI, Coronal View
Companion Patient 2, NormalOur Patient L.S.
PACS, BIDMC
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Use of Imaging in Abnormal Placental Implantation
Impression:1. Marginal Placenta2. Placenta Percreta
Recommendations:• Prevention of life-threatening delivery• Prepare Urology, Gyn/Onc, Interventional Radiologist Consult• Prepare for Cesarean Hysterectomy, Partial Cystectomy• Prepare fluids, RBC, FFP availability at delivery
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Our Patient L.S.: Cystogram after Partial CystectomyOur Patient L.S.
KUB Cystogram with Contrast: Scout, Filling, Frontal View, Right Oblique View. PACS, BIDMC
At 29 weeks GA, presented with progressive bleeding and contractionsProceeded with deliveryCesarean delivery, supracervical hysterectomy, partial cystectomy
Estimated blood loss: 4500ccReceived 5 liters IV fluids, 6 units of packed RBC, 2 units of FFP
Cystogram after partial cystectomyIrregular contour consistent with partial cystectomyNo evidence of bladder leak
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Our Patient L.S.: Epilogue
• Baby girl was born at 31.1 weeks– Liveborn female weighing 1550 grams– APGARs of 2 and 8– Admitted to NICU
• Last progress report indicates: – The baby was still in NICU at 37 weeks– She would go home at 39 weeks– She has been successfully breastfeeding
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Agenda
• Patient L.S.• Menu of Tests• Anatomy of Female Pelvis and Placenta• Abnormal Placental Implantation• Film interpretation• Differential Diagnosis• Conclusions
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Conclusions
• US and MRI are preferred imaging modalities during pregnancy to avoid fetal exposure to ionizing radiation
• Abnormal placental invasion can lead to life-threatening hemorrhage
• No imaging modality diagnoses abnormal placental invasion with absolute accuracy
• US and MRI can help make pre-operative plans to prevent life-threatening emergencies
73
Acknowledgments
• Gillian Lieberman, MD• Tejas Mehta, MD, MPH• Kei Yamada, MD• Shayna Roberts-Klein, MD• David Li, MD, PhD• Aaron Hochberg, MD• Maria Levantakis
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