Clinical Dilemmas-a pictorial essay and open ended discussion
This is a series that will present images of clinical dilemmas with a brief supporting write up. The focus is to encourage thinking of several diagnostic possibilities.
In this case, we follow a anonymized conversational transcript of discussions between Dr. Rijo Mathew, Dr. Krishna C, Dr. Bavaharan and Dr. Neelam Jain; members of Fetal Radiology India SIG.
Case submitted by Dr. Rijo Mathew, AMMA Scans, Kochi, Kerala
A Rh negative lady with a prior LSCS, lady with 14 weeks pregnancy with 10 x 4 cm focal mixed echogenic lesion in the lower part of anterior placenta, covering the internal os, with multiple tiny cystic spaces simulating the appearance of hydatidiform mole.
Since she was an Rh negative mother with previous LSCS, I was worried about placental adhesive disorders. On a transvaginal scan, the lesion was covering the internal os, there is mild thinning of myometrium at LSCS region, but placental outline is sharp. I thought the chances of percreta is out. Increta less likely. In this case, uterine and umbilical doppler PI values were predictive of FGR/SGA. Even the power doppler within placenta at the low sensitivity settings at 3cm/sec, show reduced vascularity with paucity of vessels crossing the placental thickness.
Transcript of conversations
Member 1: Now what is the pathology of the placental focal lesion? Is it from the placenta? Is it a placental pathology? Can it be a partial mole? Can it be low laying placenta with placenta accreta /increta from LSCS region? Can it be a placental organised hematoma or placental chorioangioma or tumours? The choriodecidual degenerative changes that we come across in blighted ovum or missed abortion if left alone can it assume similar appearance?
Member 2: This can be a Hydropic degeneration, normal varient. But can hydropic degeneration be a sequelae to a retroplacental hemorrhage?
Member 3: Is there a formed fetus ? Molar pregnancy?
Member 1: Yes. 14wks. Fetal growth, structure, liquor, uterine dopplers normal.
Member 4: Partial mole can be like this, do HCG values
Member 2: HCG will be Normal. Please observe. The fetal side is affected. Not the maternal side.
Member 1: In this case, Uterine doppler PI percentile. Right 55th, Left 99th, Umbilical PI percentile 99
Member 3: Is there a separate placenta ? The multicystic lesion is in the lower part of placenta.
Then it could be Focal placental mesenchymal dysplasia, do a maternal serum AFP.It will be high
Close dd will be twins with one complete mole, In complete mole afp values will be normal. It’s not related to bleeding PV or retrochorionic bleed. This pregnancy may be uneventful or may have few complications like preterm or fgr in the second trimester. Watch for cysts in liver or visceromegaly or omphalocele. Rule out Beckwith-Wiedemann syndrome.
Hydropic degeneration cannot be associated with normal growth pattern.
Member 2: Depends on how much of normal placenta remains. If 30 percent or more of placenta is degenerated then yes. If 80 to 90 percent is normal, whose pregnancy is still progressing, then why FGR should occur?
Member 3: Hydropic degeneration cannot be focal involvement of placenta since it’s a pathological process that involves the placenta in its entirety. More over in hydropic degeneration.. bhcg has to be in declining trend or low.
Member 2: This case. Imagine there was a cotwin. Demise of cotwin Could have resulted in complete hydropic degeneration of placenta of cotwin. Not the other placenta.
Member 3: That’s possible. It may be twin. The question here is are there two placentas or single placenta ?. Bleeding may be a completely independent phenomenon. Hydropic degeneration cannot be focal .. if we say simple hydropic degeneration— it means a failing pregnancy.
Member 2: This case appears they are separated from main placenta. They may be lying together. There is a clear gap. So pregnancy has failed and complete hydropic degeneration has occurred in cotwin placenta. But we have not seen the 6 weeks image or video. So that doubt remains.
Most important take home point in this case is do not panic.
Follow up every month. If focal mesenchymal dysplasia also why panic.
Second important thing, do not do double marker. Please do first trimester quad . Invasive placental pathology is such a confusing aspect in first trimester. If AFP is normal in such cases in first trimester, this gives a lot of relief. Also retrospective analysis. If AFP is high in first or second trimester, call the patient again , if everything is normal re-examine the placenta. Also on first trimester quad we do plgf. A important marker of FGR especially in abnormal first trimester placenta
Member 1: What we need to prove in these cases is the presence of a twin sac or missed abortion, or it can give a confusing picture when presented with bleeding. A thorough evaluation of the subchorionic hemorrhage during early pregnancy scans may throw some light into it.
The beta hcg values of the case discussed has come. 3,10000 at 14wks.. High (done elsewhere so could not MoM).
Leaving these for the inputs of the team, let me move forward with the management challenges involved in these cases.
If Beta hcg and AFP values within normal range, are we justified not to advise placental biopsy?
How do you proceed?
How do you counsel? How do you delineate the presentation of risks based on evidence and fear?
How do you incorporate the evidence and prognostic value of each sign and test to proceed further? Essentially, we have to figure out if this is a finding of no relevance to the continuation of pregnancy, a finding of something that has already happened and is unlikely to further affect pregnancy. Or, is this a finding that reflects an ongoing process and may or may not affect continuation of pregnancy. We also have to build an idea of estimates for adverse events during pregnancy and counsel accordingly. Counseling based on an understanding of evidence can be the difference between continuation of pregnancy and termination.
The obstetrician’s concerns are important in this case. The increased chance of severe antepartum hemorrhage that can even result in hysterectomy or uterine artery embolization is a concern. Other risk is the increased risk of choriocarcinoma which has to be monitored. There are risks for preterm birth, FGR, PE, and IUFD. At the same time, these are risks that can be monitored and properly managed in a good secondary and tertiary centre.
This mother was counselled elsewhere and opted for termination.
We are also providing links to two case reports for additional reading
We welcome presentations of clinical dilemmas and conversations around it. These can be in a conversational style and aim to encourage thinking of different possibilities. Please send a transcript to firstname.lastname@example.org (Please anonymized images and conversations).