Placental Mass-Like Lesions



Placental Mass-Like Lesions


Roya Sohaey, MD



DIFFERENTIAL DIAGNOSIS


Common



  • Acute Placental Abruption


  • Placental Implantation on Myoma


  • Focal Myometrial Contraction (FMC)


  • Chorioangioma


  • Complete Hydatidiform Mole


Less Common



  • Placental Teratoma


ESSENTIAL INFORMATION


Key Differential Diagnosis Issues



  • Routinely evaluate the whole placenta



    • Sagittal views



      • Midsagittal (with lower uterine segment)


      • Right and left parasagittal


    • Axial views



      • Upper, mid, lower


  • Identify location of mass



    • In the placenta



      • Chorioangioma


      • Extension of abruption


      • Teratoma (rare)


    • Behind the placenta



      • Abruption


      • Myoma


      • FMC


    • Replaces the placenta



      • Complete hydatidiform mole


  • Interrogate mass with Doppler



    • Masses with flow



      • Chorioangioma


      • Complete hydatidiform mole


    • Masses with little or no flow



      • Abruption


      • FMC


    • Characterize pattern of flow



      • Peripheral flow with myoma


      • Linear contiguous flow with FMC


Helpful Clues for Common Diagnoses



  • Acute Placental Abruption



    • Identify abruption location



      • Marginal (most common)


      • Retroplacental


      • Preplacental (most rare)


    • Retroplacental abruption can mimic mass



      • Thick placenta may be only finding


      • Acute blood isoechoic to placenta


      • Blood becomes hypoechoic with time


    • Doppler shows no flow in hematoma


    • Look for signs of fetal distress



      • Assess fetal heart rate


      • Fetal tone and movement


      • Cord Doppler evaluation


    • Assess amount of placenta detached



      • < 30% associated with good prognosis


      • > 50% associated with > 50% fetal death


  • Placental Implantation on Myoma



    • Myoma appearance



      • Hypoechoic to uterus and placenta


      • Calcifications are common


    • Degenerating myomas



      • Central cystic change


      • Decreased blood flow


    • Retroplacental myomas are associated with abruption



      • Use Doppler to differentiate blood from myoma


    • Rarely associated with intrauterine growth restriction



      • Large amount of placenta implanted on myomatous uterus


  • Focal Myometrial Contraction (FMC)



    • Normal finding throughout pregnancy


    • Uterine wall contraction


    • Inner contour affected most



      • Inner uterine bulge


      • Outer contour relatively preserved


    • FMC tends to be isoechoic to uterine wall


    • Will resolve or change with time



      • May take more than 30 minutes


      • May need to reassess on follow-up exams


  • Chorioangioma



    • Benign, vascular placental tumor



      • Most < 5 cm


    • Common location is on fetal side of placenta, near cord insertion site


    • Ultrasound features



      • Well-defined mass


      • Generally hypoechoic


      • Heterogeneous if hemorrhage, infarction or degenerating


      • Variable amount of blood flow


  • Complete Hydatidiform Mole



    • Most common type of gestational trophoblastic neoplasia



      • 100% paternal genetic makeup


    • Variable ultrasound appearance



      • Placental cysts


      • Anembryonic gestational sac



      • Associated perigestational hemorrhage


    • Doppler findings



      • ↑ Flow between cysts


      • High-velocity, low-impedance flow


    • Associated theca lutein cysts



      • Bilateral, multiseptated ovarian cysts


      • Seen in 50% of cases


Helpful Clues for Less Common Diagnoses



  • Placental Teratoma



    • Extremely rare


    • Benign mature teratoma


    • Calcifications suggest diagnosis


    • Differentiate from demised twin next to placenta


    • Histogenesis theories



      • Twin incorporated in placenta


      • Primitive gut tissue grows in placenta


Other Essential Information

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Aug 10, 2016 | Posted by in OBSTETRICS | Comments Off on Placental Mass-Like Lesions

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