Fetal Diagnostic Imaging: Cincinnati Fetal Center

Uh, we will be starting the next session on fetal diagnosis imaging with some of the key markers that we'll be looking for, the things that will help us predict which babies would be most, um, applicable for intervention. And I wanted to start, uh, with just showing you a couple of the things that I think are important as we do these evaluations. When we look at fetuses that have bladder outlet obstruction that are have oligohydramnios as a presenting part of their presentation, we look at pictures similarly to this, where we'll have posterior placentas, uh, we have hands and feet that are up in front of the face. We'll see a compressed chest. Often it's difficult to see the stomach, and you can see the bladder at the base of the picture in the lower right. Where the umbilical cord and the hypogastric arteries are bifurcating around it, it doesn't allow you really to have much opportunity to evaluate the anatomy to find associated anomalies. What is our practice here is to do an amnio infusion, which we know is going to be needed if the patient is a candidate for a shunt in order to place the shunt properly. We start with this amnio infusion. It gives us the opportunity in many cases, as Doctors Johnson and Ryan talked about getting a karyotype. We can usually get a karyotype from uh a washing of the amniotic sac by doing this amnio infusion. It allows us to see very clearly the uncompressed chest, so that we can look at the size of the chest, compare it to norms, which can help us predict pulmonary hypoplasia. We can look at the heart in its relative size, and some of those ratios are very critical in those prognoses. We can also look for associated anomalies of the heart which are not. Common in fetal genital urinary disease. You can see the hands when we're looking for complex genetic syndromes. Sometimes the posturing of the hands and feet are part of that diagnosis. And so, in the upper right, you'll see an expanded hand with fluid that we've placed into the sac. Lower left, you can see the foot. We can see the placental cord insertion site to make sure that these are not velamentous insertions, which could complicate shunt placement. And we can do the same thing while we're treating babies as well. After intervention, if the fluid volume drops off again because of end-stage fetal renal disease, we can repeat those kinds of infusions through several different techniques, allowing us to have a better access to the fetuses, um, to the view of the fetus, so that we can make clinical decisions. What I'm gonna do now is uh switch over to Doctor Jaco uh on our faculty here in maternal fetal medicine, and he will be discussing genitourinary imaging and some of the key findings that are critical in the evaluation. Good morning. Uh, I, I would like this part of the presentation to be more interactive because I assume many of the people on the uh conference have already been doing this, uh, for an extended period of time. And so if there's questions, please feel free to, to log in and we'll answer as we can. Uh, with Bladder outlet obstruction and with other genitourinary abnormalities, we start out with problems like this first image, which is just profound oligohydramnios, which makes it difficult to make the diagnosis and as I, as Bill just talked about, amnio infusion becomes very handy in our in our workup. When we're looking at these babies, our challenge is trying to determine exactly what the etiology is, and in this picture, we've got a problem of fairly dilated and tortuous ureters, and sometimes we've had referrals in that the referring physicians just got confused about whether this was a big bladder or big ureters, and I think it's important from a family counseling standpoint to make sure we keep that straight. Um This, this, uh, image is kind of goes back to what's already been said twice this morning, and that is this diagnosis when I was young, which was 1000 years ago, was a condition that we diagnosed in the mid-trimester to early 3rd trimester, and in this circumstance we see a big bladder that's already all the way up to the diaphragm in a pregnancy just outside of the first trimester. So we're now able to begin to make this diagnosis very early in gestation. You're going to see this picture probably another 100 times during this conference. This is a keyhole configuration of the bladder that we see so commonly with posterior urethral valves or the other obstructive neuropathies. Uh, in this circumstance. What we really need to do is help parents understand what we think the renal function is going to be. Because we've got some other strategies for the pulmonary outcomes. And so when we're looking at the kidneys, we want to look at the echogenicity of the of the parenchyma, we want to look at the orientation of the renal cysts, and that allows us a better opportunity to to have an assessment of postnatal renal function. In this, in this image, what we've really got is uh uh we, we'd see that their kidneys, we see that the renal prankum are uh echogenic and irregular, uh, but more importantly, it's just not normal looking. Uh, I know I've got a short time, so I'm gonna try to keep up. In, in these, in these images, again, you can imagine that there are going to be practitioners not as experienced as many of the members of this audience who wanna believe that those are big dilated um uh kidneys, but in fact, that could easily be dilated ureters, especially given the fact that it's tortuous and, and extends down below the lower pole. Uh, I kind of give away things at times with my images, but, uh, with, with, uh. With these, we've really got issues of uh irregular configuration. We've got uh inconsistent echogenicity and a distribution, uh, a wide distribution of cyst size. Anybody have any questions? We're doing OK with that? Doing OK. Um, Early in the disease process, what we've got is the renal cysts can be distributed around the outer pole of the kidney. And then as the process progresses, you begin to see things become more disoriented and distorted. The other challenge is making sure that we really do have 2 kidneys. In this particular case, we saw the large multicystic dysplastic kidney, but it took us a little bit of time to come back and notice that that right renal fossa didn't contain normal kidney tissue or any kidney tissue at all. Uh The need to make sure you look for other abnormalities and and associated anomalies is is well established. In this circumstance. I just threw this in here as a kind of reminder to myself to, to remind you guys that this is a condition that's not just isolated to the genital urinary system, but you've got to make sure you look for a variety of other abnormalities. And then finally, as Bill was pointing out, with oligohydramnios, the problem really comes back to pulmonary hypoplasia. And in that circumstance, you really need to help the parents understand that. If you've got pulmonary hyperplasia in place, it's going to be very difficult to correct that. In this image, as you guys, I'm sure have seen before, we've got a bell-shaped thorax with the lower ribs being pushed out. That's because the pulmonary circuit is just not developing normally and the bladder itself is, is very dilated. So I think I've used up, yeah, and it really pertains to this. We talk about pulmonary hyperplasia with oligohydramnios, and I'm wondering if, uh, in your counseling, in your experience, if the size of the kidneys and elevation of the diaphragm is a further discriminator of risk of hypoplasia. I, I think that's a very important point to make. If you've got the kidneys. It high enough or big enough that they are impairing diaphragmatic excursion, you're gonna have a bigger problem and a more likely diagnosis of pulmonary hypoplasia. Look back at the data on frantic nerve dissection and, and the loss of diaphragmatic movement as a primary reason for pulmonary hypoplasia. Big kidneys can cause your diaphragm to stop moving just as well and create the same crisis for pulmonary development. And another question from the audience, do you think that ultrasonography is a, uh, alone is an acceptable diagnostic modality, or does fetal MRI, uh, need to be done in this day and age? Well, actually, I've got a whole series of slides. I have to admit that, uh, although I do ultrasound for a living and I really need to be committed to ultrasound because that's how I do this, the reality is from a parent's standpoint. I think that MRI provides a very real opportunity uh to give them a visual image that they can uh uh better, get a better handle on the diagnosis. So I don't think for this condition, ultrasound alone, I, I think it, it, for me, it works great for the parents, MRI is a, a very important uh discriminator because it gives a big picture of the baby and. The images are pretty clear for parents to see when you're dealing with a renal abnormality.