Hi, Everybody! I'm moderating this week! Whatcha got? :]

Evaluating the placenta is very serious in reference to location. With being such a beginner I am still trying to figure out viewing the internal cervical os. If the bladder is fully distended it will be inaccurate measurements. For example > 5cm, have the pt post void. When in doubt, do EV to confirm the cervix measurement accurately. Should be 3-4 cm. (Make sure to not include the isthmus because this could compromise the length as well.)

In addition differentiating Gestational Trophoblastic Disease: Chorioangioma (benign) versus choriocarcinoma (malignant). With chorioangioma displays some flow. Choriocarcinoma is super vascular. Always use color flow to help differentiate. 

Lastly, I think Morbidly adherent placenta is serious of patient risk: Placenta increta and percreta are serious because mortality rate is high with these abnormalities. Understanding the difference "Increta" chorionic villi is deep into the myometrium, whereas "Percreta" penetrates through the myometrium and causes severe blood loss. Understanding the location of the placenta to correctly identify what type of invasion. 

Placenta abruption is definitely one of the more serious pathologies in terms of patient risk factors due to the high mortality rate and extreme symptoms that mom may go through when this occurs. 

Definition of placenta abruption: separation of a normally implanted placenta before delivery of the fetus. 

Signs & symptoms (maternal): rigid/painful uterus w/ vaginal bleeding, acute renal failure, shock

Signs & symptoms (fetal): distress/demise (20-60%), IUGR, hydrops, anemia, preterm labor

I couldn’t imagine going through the pain of the placenta ripping off the uterine wall, and then having the (very high) possibility the baby dying. That must be such an emotional draining experience one has to go through, especially after carrying the little babe for so many weeks. 

I think the placenta is often overlooked because we are so focused on baby’s anatomy and checking for anomalies that we forget to really assess mom’s anatomy, not just take the required images. When evaluating the placenta, we are mostly looking for location (to rule out previa) and cord insertion to make sure it is centrally located (& rule out marginal insertion). We rarely ever put color flow on the whole placenta, and after today’s lecture it makes me want to do it on every routine survey to rule out vasa previa, circumvallate placenta, placental hemorrhage, etc.

When scanning OBs, I find myself under a lot of pressure to get all of these images done in an hour (and that’s with no anomalies found). Sometimes I wish we had more than an hour for these exams. I think this is mostly because I am still a student and don’t have that scanning  speed yet. Can anyone else agree?

Hey All, 

I had so much fun in class today learning about all the different placenta anomalies. Getting in groups really helped me understand the difference of each one better. One that has been hard for to identify is marginal, partial and complete placenta previa. I get the concept, but visualizing it on gray scale makes me nervous that I am not seeing it correctly. Nonetheless, placenta previa is a very serious issue when diagnosed with complete previa. Granted, we know the placenta normally moves away from the cervix as the pregnancy progress, however when complications arise, it can be harmful to both the fetus and the mother. 

According to MedinceNet, "studies have shown a reduction in fetal growth associated with placenta previa, bleeding of placenta previa can increase the risk for preterm premature rupture of the membranes and placenta previa can have a significant emotional impact on the pregnant woman" I believe it is so important to have an eye for such previas so we can accurately document for future follow ups. 

https://www.medicinenet.com/pregnancy_placenta_previa/article.htm

Here some images that I have chosen from a goggle search on placenta previa, to help train my eye. Correct me if I am wrong on these! 

Complete Previa? 

Low Lying?

Marginal Previa? 

It gets missed because I'm too overwhelmed chasing a fetus around the womb to obtain my 100 or so images for the radiologist :). The placenta location typically such an easy task to check off the list. Location, distance from cervix, cord insertion and DONE. From the reading a common cause of placenta bleeding that end in fetal demise about 50% of the time are placental hematomas. These will be bleeds behind the placenta caused by the frondosum detaching. If the area of detachment is too large this will have a negative impact on the developing fetus getting all of the oxygen and nutrients it needs to progress. This does not always cause vaginal bleeding since the bleed can be contained behind the placenta so the mother may not have many symptoms for us to key in on. This is also a super common occurance which makes them something we need to take seriously. The risk for fetal demise increases with the size of the bleed. A differential would include a subchorionic hemorrhage which is the most common cause of first trimester bleeding, often associated with normal implantation. 

There are some serious pathologies that involve the placenta. I think that the most dangerous pathologies are placenta acreta, velamentous insertion, and placenta abruption. Placenta accreta, increta, and percreta are dangerous because the chorionic villi start attaching to the myometrium or in severe cases penetrate the uterus into the bladder. This is bad because after delivery because the mother can bleed out. According to American pregnancy association about 75% of all cases end up being placenta accreta which is less severe. The next placental pathology is a velamentous insertion of the placenta because the cord is not covered in Wharton’s jelly. Another important pathology is placenta abruption because the placenta can detach before the baby is born causing a demise due to lack of oxygen and nutrients.

Placenta Accreta: Symptoms, Risks and Treatment. (2019, October 10). Retrieved from https://americanpregnancy.org/pregnancy-complications/placenta-accreta/.

The placental pathology that stood out to me the most is the placental abruption - the concealed type. Placental abruption is a premature separation of the implanted placenta before delivery of the fetus. Our textbook states that mortality rate is 20-60% in these cases and placental abruption account for 15-25% of perinatal deaths. The mother may present with problems like vaginal bleeding, pain, preterm labor and a “board-like” abdominal tone. Causes are many, including history of abrupitons, short umbilical cord, placenta previa, tobacco & cocaine use, pre-eclampsia, thrombophilia. In 50% of abruptions resulting in fetal death, mothers experience hypertension.

 A concealed abruption is one that doesn’t present with obvious symptoms of bleeding, but is silent and bleeds between the placenta and uterus. This results from the rupture of spiral arteries. Sonography is not very sensitive in showing this because the hemorrhage may look isoechoic to the placenta, may be smaller or may appear as thickening of placenta.

 Placental abruptions are treated with an induced labor or a caesarean or if the abruption is only a small part of the placenta then the patient may be monitored closely.

 I think placental pathologies are often missed because it is not given enough time, it appears as an easy evaluation and if the rest of the fetal anatomy looks ok the sonographer may not be alarmed to look closer. As a student, I think it is because there are so many pictures we need to take that we just rush through to obtain them and then sweep more slowly to check for pathology. Today I completed a limited growth on a 3rd trimester, but the only picture I couldn’t get was the placenta! It appeared sooo different from what I was “used” to seeing. It had so many calcifications and uneven curvy contour that completely distorted the whole shape and echogenicity of the placenta. I”m glad I was exposed to this placental presentation:)  

I feel that the highest risk placental abnormalities are percreta, placenta previa, vasa previa, and retroplacental abruption.

Percreta: A placenta that has invaded beyond the uterus and into the bladder carries a high risk of premature delivery, which can be dangerous for baby. There is also high likelihood of maternal hemorrhage before, during, or after labor and often must either have a hysterectomy or methotrexate therapy to stop the hemorrhage.

Complete Previa: The thinning and spreading of the placenta to accommodate for an impending birth can separate the placenta and cause maternal hemorrhage, shock, possible c-section/hysterectomy. The baby could suffer complications from loss of oxygen, face premature delivery, and lose blood.

Vasa Previa: Due to the velamentous cord insertion and contact with the cervix, the dangers to the fetus are hemorrhage, exsanguination, or death.

Retroplacental Abruption: Due to the fact that the placenta breaks away from the uterus, it can lead to maternal hemorrhage & shock, need for blood transfusion, failure of kidneys or other organs resulting from significant blood loss, and even hysterectomy to stop bleeding. The baby can face restricted growth from not getting enough nutrients, loss of oxygen, premature birth, or even being stillborn.

Some of these abnormalities can be challenging to diagnose due to visualization issues, not thoroughly imaging the placenta in its entirety, or rushing through maternal anatomy in order to examine fetal structures. Additionally, several types of bleeding can be isoechoic to the placenta itself.

Hello friends,

To me the most serious of all the pathologies in the placenta is a vasa previa. I've seen some if my preceptors put color on the cervix and on the placenta for the cord insertion, however, without putting the color just in front of the cervix, vasa previa can be easily missed. It can especially be missed because even though it can be seen with velamentous cord insertion, it's not always. With a normal cervix and a normal cord insertion, there may not be any clear red flags.

Without finding this, the patient's doctor wouldn't be able to direct the her with the safest practices for her situation (bed rest for instance). Without knowing this, the cervix could open to prepare for the baby's birth and the fetal membranes overlying the cervix could rupture. Depending on how far mom is from the nearest hospital, she could bleed out and there could be serious consequences for her and the baby.

To prevent something like this from happening, I think the best idea is to put a color box on the image from internal cervical os to the placental tip. This shows that there are no fetal membranes that are going to cause problems down the line. 

It my opinion, it's so easy to overlook the placenta (and it's importance) because there are really one three images that we get of it (at least at my site). We get Placenta Long, Trans, and Placental CI. We don't spend too much time focusing on it, so it's easy to forget all the things that could go wrong. And if you think about it, if there is something wrong with the placenta, the chances of there being something wrong with the baby or mom is pretty high. 

From now on I'm really going to take a bit more time to appreciate and thoroughly check out that placenta!

To help with recognizing placenta pathology. 

Can everyone post ultrasound images of different placenta pathology? And then write the answer to what it is backwards below the images, so we see the images first before the answer?

For example:

Answer: noitresni suotnemelev

I think the succenturiate placenta is the most serious in terms of patient risk factors. It develops as a result of non-involution of the chorionic leave that supposed to become smooth as soon as chorionic frondosum will attach to the decidua basalis to form a primitive placenta. As a result, usually one or sometimes more small accessory lobes of different sizes are developed in the membranes at a distance from the periphery of the main placental mass. The succenturiate lobes connected to the main placental mass via vessels of fetal origin. Because it is a rare placental anomaly (3% - 8%), it might be overlooked by a sonographer thinking that it is  intrauterine contractions, a fold in the placenta, and some fibroids. Umbilical cord insertion with this type of placenta most commonly is seen into the main lobe. However, not recognizing the succenturiate placenta and determining locations of all lobes can lead to serious outcomes and complications, such as increased risk  of placental infarction, placenta previa, vasa previa, heavy postpartum hemorrhage associated with retained product of conception and perinatal mortality. For instance,

• When the accessory lobe is implanted over the internal cervical os, it should be considered as a placenta previa. If underdiagnosed, cervical dilation during delivery will result in profuse hemorrhage and perinatal mortality rate can be as high as 100% because hemorrhaging can lead to fetal anemia and shock.
• Retention of the accessory lobe(s) after expulsion of the main placental mass will definitely result in serious hemorrhage.
• Hemorrhage may occur from the vessels within the membrane, which connect the succenturiate lobe to the main placental mass, because they are not protected by Warton’s jelly.
• If vascular connections between the main placental lobe and an accessory lobe go over the cervix, vasa previa is diagnosed.

Hello Sonosistas, 

You all did a great job with the most dangerous placenta anomaly that could happen I was going to pick placenta abruption, but seems you all have that one down. Another placenta anomaly we will encounter is placentomegaly and small placenta the normal placenta should be around 5cm, so once we do our initial scan we should use our subjective assessment and check location and placenta size. Having a placenta that is too large can cause fetal hydrops, maternal anemia, gestational trophoblastic disease these were from our recent quiz. Having a placenta too small can lead to placental insufficiency and IUGR. Overall having small placenta or placentomegaly will less likely lead to fetal demise. Here is an image of placentomegaly

Having placenta percreta is another serious condition of the placenta that can arise. It happens as a final stage. The placenta accreta is the first to arise only to the myometrium. Then second stage the placenta increta the placenta grows into the myometrium. Then it goes into the final stage placenta percreta where the placenta grows outside the uterus possibly as far as  the bladder I remember someone asking for an ultrasound image in class so I have posted one for those visual learners. Placenta percreta is rare, but it can happen. With placenta percreta being the most severe and life -threatening for mother and baby we need to assess the borders of the placenta as well.

https://www.marchofdimes.org/complications/placental-accreta-increta-and-percreta.aspx 

Hello! 

I think all placenta abnormalities are to be taken seriously and follow up to ensure fetal well being as well as moms and ensure a safe delivery. However  I believe vasa previa would be most of concern. 

what is vasa previa ? vasa previa is rare, its when the fetal vessels within the run across or close the cervical os. why might you say this is of concern ? its due to the fact that these vessels are bound to rupture and cause a life threatening hemorrhage. Per our Hagen Ansert book there is two reasons that may cause vasa previa 

1. due to the velamentous insertion of the umbilical cord to the placental membranes which cross over the cervix 
2.  when a succenturiate lobe is present and the connecting vessels transverse the cervix

Dr.Wilson had a great drawn picture illustrating the vessels near the cervix, this image is the closest I could find to hers 

as you can see the fetal vessels so very closely placed near the cervix is not good and concerning !

Evaluating the placenta is just as important as evaluating the baby because without the placenta there is no baby to evaluate. The placenta is the conduit by which the baby receives its nutrition and oxygen so it makes sense that we need to take time and care in evaluating it. I feel like we can get so wrapped up in baby and his/her growth development that the placenta and its health get neglected.

In my opinion the placental abruption is the most serious of the conditions. It carries a fetal mortality rate of 20-60% which twice that of previa. Placental abruption is the premature separation of the placenta from the uterus. Maternal signs and symptoms can include pain, vaginal bleeding, acute renal failure, shock, and preterm labor. Fetal symptoms include IUGR which can lead to hydrops, anemia, and even death. 

I think this is the most serious because it is a condition that happens suddenly and without warning. There are risk factors that make it more likely to happen such as hypertension, drug use, and trauma, however, it can also occur spontaneously. I think that along with the spontaneity and pain, the fact that the baby could be born prematurely and or die makes it the most serious. Unlike the previa (which is another serious placental problem) it is not detected on the ultrasound months in advance where one can prepare accordingly for the birth. I think also about the mental health of these women who are late in their pregnancy and have a sever abruption that leads to fetal demise because of a prolonged period of oxygen deprivation. 

The pathology that stood out to me the most was placental abruption, when the placenta prematurely detaches from the uterine wall depriving the fetus of its blood (oxygen/nutrient) supply. The larger the the abruption is the greater the likelihood of fetal demise. This can also cause maternal blood loss and stimulate premature contractions. When a moderate-severe abruption is detected the baby needs to be delivered right away typically by c-section. A previous placental abruption increases the risk for future pregnancies (19-20%) which is why it is important to get the patient’s clinical hx pertaining to previous pregnancies before starting an exam. The placenta gets somewhat skipped over because some anomalies are hard to see with ultrasound and because we have so many other standard images pertaining directly to the fetus during routine ultrasound examinations that it gets taken for granted.

Source: https://www.marchofdimes.org/complications/placental-abruption.aspx

Source: https://radiopaedia.org/articles/placental-abruption?lang=us

Hi, Everybody.

To wrap up this week's discussion on placenta I've attached pictures and a link to the chart I made for placental pathology. Go to the link for a larger view: https://docs.google.com/document/d/1VIymKHHTiloJCAalSi7kOqJ2IpYhvK6K6riMaQl2GZA/edit?usp=sharing

It's a lot, so I figured I'd just put it all together with the images instead of writing it all in the DB.

From our discussions it seems like the easiest thing we can do to avoid missing placenta pathology would be to put color on the placenta and the surrounding area. If we were to miss pathology it would be because we are not taking the time to appropriately assess echogenicity and surrounding structures. Just this past week I saw an emergency OB, 12 weeks. She had been to emergency 4 times. On the 2nd time the sonographer had written down perigestational hemorrhage. On the 3rd exam the sonographer had written negative for abnormality. I witnessed the 4th exam and it was obvious there was a large perigestational or subchorionic hemorrhage. OBVIOUS. However, when we were talking to the patient she said that the last sonographer had been grumpy and didn't spend too much time with her or even let her see the screen. It was apparent to us that the third sonographer had missed the hemorrhage even though it had grown in size from the 2nd exam. Perhaps the other sonographer really didn't see it. But it makes me wonder if he even checked the priors. 

This story is just an example of how much influence we have over patient and pregnancy outcome. And a lot of factors can go into whether an abnormality is missed or not. The quality of the transducer, the type of exam, bladder fullness, patient's gas, patient's health, sonographer's attention, equipment available, fetus postition...all of these factors play a role in finding evidence of pathology. 

Of all the placental pathologies discussed thus far I think the two most severe in terms of patient risk factors are abruption and percreta.

I am choosing to focus on percreta though as I feel it is definitely the most severe. Placental percreta is a condition in which the placenta invades the uterine wall. In placenta percreta, the vascular processes of the chorion, a fetal membrane that enters into the formation of the placenta, can invade the full thickness of the myometrium. This can cause an incomplete rupture of the uterus. The chorionic villi can go right on through both the myometrium and the outside covering of the uterus, causing complete and catastrophic rupture of the uterus. From there it can start to invade other organs and cause a complete and catastrophic mess.  In fact, mortality rate is correlated to the extent of involvement of surrounding structures, which could potentially include the bladder and rectum.

When placenta percreta is complicated by bladder invasion, mortality rates have been estimated as high as 9.5% and 24% for mother and child, respectively. Knowledge of this condition and expectant management are especially important, as the incidence is on the rise—an estimated 50-fold increase in the last 50 years—attributed to the increased frequency of Caesarean deliveries. That is crazy, y'all! So keep those eyes peeled.

To get a better idea of how severe the problems can be when dealing with percreta I found a case study of of a 38-year-old woman who presented at 24 weeks gestation with vaginal bleeding and was found to have complete placenta previa with placenta percreta invading the urinary bladder. Her hospital course was complicated by bilateral pulmonary emboli. She underwent an exploratory laparotomy, repeat Caesarean section, and total abdominal hysterectomy. Because of placental invasion into the bladder, the procedure was complicated by bladder and ureter damage for which urology carried out repair.

In this case, it is amazing that the mother survived, but also a great example of how previa and percreta can often coexist and allow for invasion into the bladder. I have included and image from the case study.

Source:

Smith, Z. L., Sehgal, S. S., Arsdalen, K. N. V., & Goldstein, I. S. (2014). Placenta Percreta With Invasion into the Urinary Bladder. Urology Case Reports, 2(1), 31–32. doi: 10.1016/j.eucr.2013.11.010