about anorectal malformations in terms of the radiology. And I have some distinguished panelists. And actually Brent Adler's not here right now, but Jeffrey Avancino from Seattle. Wonderful. Greg Bates from here at Nationwide. Luis Del Torre. Is Luis here? Awesome. And Keith Jorgensen from Spokane. And then me. So let's go ahead and talk a little bit about anorectal malformations. And I just need, this is my slide going forward. Awesome. Prenatal diagnosis. So talking about the prenatal diagnosis, first of all, I want to say about the prenatal diagnosis that there are some papers that describe how you can make a prenatal diagnosis of anorectal malformation. But I have to say that in boys, it's not very good. We get a lot of boys born, and it's a surprise. They may have some obstruction of the colon. We might see something on ultrasound, but maybe not. And so it's oftentimes a surprise. When is it not a surprise? It's when we get something like this. And this is a prenatal ultrasound. And do I have a pointer on the console here? I don't. Where is that? Okay, here it is. Okay, I see it. I'm sorry. Okay. So here's an ultrasound. This is an axial image of an ultrasound. And there's these two dilated structures with fluid in them and one less dilated structure. And I think these are actually representative of hydronephrosis of both kidneys and a small bladder. So if we have the people who are going to give me an A and B, so does anybody, what do they think that this is? If this is a girl, is this just hydronephrosis due to reflux? Or could this be a patient who has a cloaca? Panelists, what do you think? How about Dr. Bates? Okay. On this axial sonographic images, if there is discreetly, if we're at the level of the kidneys, to be sure, and this is bilateral hydronephrosis, I'm not sure what that third component is at that level. If we're in the pelvis, it's potentially that this could represent a dilated bladder and or hydroculpose. If it's dilated kidneys, I don't see much in the way of rendiform tissues. You're going to want to see an image down below to see what the pelvic anatomy looks like to see if there is pathologic hydroculpose or hydrometriaculpose. Is there a dilated bladder? Is there potentially a presycle mass, et cetera, et cetera? It's hard to tell from one slice. So here's another one. So a second cross-sectional imaging, probably presumptively down in the pelvis. I'm going to assume that that's the pelvic level since I don't see anything reniform. We don't see any other solid organs down there. That one of these potentially would be a dilated bladder versus two could be dilated vaginal cavities, and you could have bilateral hydrometriose. And here's a sagittal image from the same patient. So similarly in the sagittal image, what the arrow is pointing at looks like a distended rectum extending posteriorly down toward the perineum. So certainly three of the components we look for on MRI in patients with cloacal malformations would be a cystic mass in the pelvis. There are many causes of cystic masses in the pelvis. We can see presacral masses, duplication cysts, ovarian cysts, and you always have to keep in the back of your mind dilated hydrometriose. Dilated rectum, fluid distended rectum, certainly would be in the differential, and any GU anomaly. The combination of those three components in a female should make you begin to at least consider the diagnosis of cloacal malformation. And that's by our survey. Everybody mostly got the correct answer that this would be, it was about 90 some odd percent, that this would be a patient who had a cloaca, and it indeed is. And here's an MRI. So with an abnormal ultrasound, a lot of patients in centers where you do have MRI, fetal MRI, this is a sagittal image, and it does show that there is a very dilated structure here. This is probably the bladder. This is the very dilated vagina, and there is no T1 signal necessarily that is going below the bladder base in the region of the rectum. So this indeed is a patient with a cloaca. And these are actual images from patients who are born postnatally. And as you see, when you're doing a neonatal workup, it's very important to get the spine, to look for spinal anomalies, and other associated anomalies. And if you want to comment about this ultrasound... This is a patient that was presented at our institution. This is an immediate newborn with anal atresia. We see a male. So had a plain radiograph on your right and had a pelvic ultrasound on your left. So the question is, there are transverse and longitudinal views of the bowel showing multiple echogenic foci. So A is this normal meconium, or B is it abnormal meconium? We're almost there. Slow. Can you comment on the indications for fetal MRI? Right. So fetal MRI is used especially in patients who have level 2 ultrasounds that are abnormal. And specifically if there are other anomalies as well. So fetal ultrasound brain anomalies, renal anomalies. We often do it for prognosticating for parents. Certainly if they find something that looks like abnormal GU tract and they are female and they come to a center that potentially where they either want to guide the parents on what to do or on guide the parents on what to do in terms of the actual viability of the pregnancy and for genetic counseling. Or they have a situation where they can do something prenatally. Certainly in a patient like this they would not probably do anything prenatally, but it can help the surgeons know what to do just at the time of delivery. Maybe even have the patient delivered at a center where they can take the patient right from delivery right to the surgical suite. So it can help in that respect. Do we have a result from the last question or we cancel that one out? We'll go ahead. So this is abnormal meconium. These are calcified enterolus in the GI tract. If you look carefully at the examination of the atom in the KUB, on the left atom, and you may or may not project, but there are multiple punctate radio densities extending up there. So you know that that's calcification. So you know that there is urine mixing with meconium, and that tends to calcify fairly quickly. So this patient has a rectal GU connection. It's not going to be simply a peroneal fistula. He has connection with the bladder and or urethra at some point and has retrograde filling at this point. So we know that there's going to be at least presumptively a bulbar fistula at this point, if not higher, because there is mixing with urine. And so when you're looking at these patients early on, if you get a KUB right after birth and you see multiple calcifications that tend to occur along the distribution of the colon, then you should suspect that there is some urine mixing with meconium with calcification. Good. Okay. So what about some radiographs that you would want to get? So in the neonatal period, certainly before I just go through individually these, the neonatal period you want to get certain exams, especially if you think that a patient has a hydroculpos, which is an urgency. As we saw earlier, the patients can have significant urinary compromise, and their creatinines can go up into the twos and threes in a patient who does not have a hydroculpos that is managed. And so immediate imaging in a female or male would be an abdominal ultrasound, getting images of the spine, the sacrum, and potentially imaging other associated anomalies. And so one of the things that we look at significantly is the sacrum. Sure. Before we move on, I just asked one question about fetal MRI. Sure. Diagnosing interectal malformations, not necessarily in a cloaca patient, but in general, the utility of that. So, again, the utility in male babies is not as good as you would like. You would like to know, if you do a test, is it going to be positive? How accurate is it? And if it's going to be negative, how much you can tell that it's not going to be an anorectal malformation? And by MRI, it's not very good. I mean, if it's not as good as a coin toss, then I wouldn't rely on it. Now, in females, that's a different story from the findings that we just described. But if you think about even ultrasound, when you see echogenic bowel. Echogenic bowel is a very nonspecific finding. You might see it in a patient with cystic fibrosis. You might see it in a patient who has bowel obstruction for some other reason. And so, it's not very good for males. It's better for females. There are a couple findings in MR, though, that are important to look for. One, after about 20 to 24 weeks, is the T1 hyperintensity on T1-weighted sequences within the colon, which is the meconium. Meconium tends to be bright on T1-weighted sequences. Before about 20 to 24 weeks, it's difficult to determine whether that meconium actually is in the colon or not. It's too difficult to determine what's small and which large. After about 20 to 24 weeks, you should begin to see on T1-weighted sequences bright meconium within the colon. Other thing you could look for, if you're in the sagittal plane, you can identify the distal component of the rectum. It should extend to a minimum of 10 millimeters below the bladder neck. If it is not, that suggests a high position of the rectum. The other component of that, if there is urine mixing with meconium, you will lose the T1 hyperintensity within the distal colon on T1-weighted sequences. It will become bright on T2-weighted sequences because now it's distended with urine. So, seeing T1 hyperintensity on the MR is important to show that there's no mixing of urine. Loss of T1 hyperintensity and suddenly bright fluid in the rectum on T2-weighted sequences suggests that there's urine in the colon. So, that's a key component as well. So, position of the rectum in relationship to the bladder neck should be at least 10 millimeters below the bladder neck. I believe in the second trimester, extending up to around 20 to 24 millimeters below the bladder neck in the third trimester. If it's below that or high for the age, that should suggest it. And seeing fluid in the bowel in a male should suggest mixing of urine. Otherwise, associated GU anomalies. Anything you might see with bladder association, cardiac anomalies. You might see dilated bowel more proximally. You might see spinal anomalies, etc. All those put together may add up to that. Don't let me think that you can't. But I think the accuracy is really what the challenge is. In males. In females, it's not as bad with cloaca. But there are other anomalies that are much lower. That the meconium does get down below. And those are the ones that are going to be challenging. Right. Particularly just a simple rectoperineal fistula. It may look normal on MR because the T1 hyperintensive meconium does sit low. And you're not going to have any urine mixing. You're probably not going to have any obstruction or any other potentially anomalies. If that's the isolated anomaly, it may be difficult. So a comment on this sacrum. So this is a patient who had an anorectal malformation. And as you can see, is this abnormal or is it normal? A, B. Abnormal. A. Normal. B. And our survey said. Well, I'll assume that everybody got this right. And that this is abnormal. In fact, well, actually some people said it was normal. Okay. Well, if you look carefully, then you can see that there's a normal looking right sacrum. But there's a hole on the left. And so this is what we term a hemisacrum. It used to be called a scimitar sacrum sometimes in the radiologic literature. And this is denoted of a mass. There's a mass. It's a long-term mass. It's eroding that part of the sacrum. And if you did an ultrasound, you potentially would see a sacral mass. A lot of times we were talking earlier about the spine ultrasound. The spine ultrasound is done from posterior. It evaluates the spine. Many times turning the patient over and actually doing an ultrasound through the abdomen will show you the actual mass. But this is a hemisacrum. And there's an associated mass. It could be a teratoma. It could be an anterior meningocel. It could be multiple elements of both. And actually having neurosurgery around at the time might not be a bad idea to see, especially if there are elements of neurologic tissue as well as a teratoma. Yeah, I think the important point from this is that we see a lot of sacral dysplasia in our cloaca and arm patients. Most of them, as you can see, if you come down from the lumbar spine, there are normal pedicles. And this one goes off to the right where it would be a sickle cell, or a sickle tight sickle cell, sickle sacrum. Most of them we begin to lose the coccyx, the lower sacral segments. But it comes up in a symmetric fashion. When you see a hemisacrum, you have to start thinking about curavenous triad. And you have to presume that there is a presacral mass there. In a patient with an anal malformation, that triad has to be assumed. And you have to look hard for a presacral mass. As we say, teratoma and anterior myelomeningocele are the two most common masses associated with the classic curavenous triad. There are other duplication cysts and rare anomalies, presacral masses, but those are going to be the most common. But if you see a scimitar or half of a sacrum there, think mass, make sure you get it evaluated for. Spine ultrasound early on, MR if you're a little bit later on. And these are probably some of the more common patients that are missed early on. They may have a perineal fistula that is not the, quote, anterior anus. It's a perineal fistula. But they get missed early on. They come in when they're four or five years old, having constipation. And you see a finding like this on an abdominal radiograph. Greg, can you comment on two things? For the trainees in the room, do you need to have a specific sacral set of films? Or can you look at the sacrum and evaluate it on an abdominal plane film in two views? That's question number one. And number two is, can you just quickly give us a very systematic way in which we can read the films ourselves quickly? A KUB? A KUB? Yeah, a KUB or an isolated sacral film. The fellows know what to look for. What are they actually looking for in that image besides the pelvis? Most of the time, in this institution, certainly, if the patient presents with an anal rectal malformation, we're going to get ordered sacral films. We stopped doing sacral films for one reason. Because in a standard AP view of the sacrum, it's an angled view of the sacrum to get the full sacrum into view. If you're going to be measuring the sacral index, as we'll talk about in a little bit and we've discussed before, that throws off your AP view. The best view for looking at the sacral index is the lateral view. No question. You get a little bit of angulation on the AP view. So, yes, you can do it on a sacral series. It is better to look at the true sacrum on a KUB because that is a direct AP view. So here, when we're doing films for measuring sacral index, it is a true AP. We don't do a full KUB, but we do a true AP pelvis and a true lateral view of the pelvis, as opposed to an AP view of the sacrum and a lateral view of the sacrum for, say, trauma. They're different views, different projections. We need the best AP and the best lateral that we can get. Now, absolutely, the lateral view is the best view for measuring your sacral index. There is less alteration. On the AP view, it always tends to be a little bit smaller than it does on the lateral view. You'd be surprised. A slight little tilt will throw it off considerably. To read a KUB, oftentimes, obviously, in a newborn, there's not a lot of fecal material. The little bit older you get, you begin to lose visualization of the sacrum because of overlying stool-filled bowel. It can be difficult to say whether there's a very mild sacral dysplasia or not. And, again, the lateral view always helps you. You know, the thousands of VCUGs we do every day. One of the key components I try to look at is looking at the sacrum. Does this patient have an unknown sacral dysplasia and a neurologic disorder that no one has picked up on and is having voiding dysfunction for that very reason? So even I look at the sacrum on the AP view. If I can't see it, I generally turn them lateral to see that it has all five components of the sacrum and the coccyx. So anybody with voiding dysfunction, make sure you look at the spine. So when you're looking at a KUB, you want to look from whatever bony architecture you have and look at each individual vertebral body all the way down, see if you can identify five sacral segments and whether they have a coccyx. Now, they're not going to have an ossified coccyx at birth, but they should have five ossified sacral segments. Other than that, soft tissues of the abdomen, you always want to look at the lung bases to make sure there's nothing opacifying the lung bases. You want to see if the heart's on the left is a key component. Make sure that always is looked at. Your stomach is on the left when you look at a KUB. Right upper quadrant should be liver. Should not generally extend down to the iliac crest. Should be above if we're talking about hepatomegaly. Similarly, there should be a spleen in the left upper quadrant, and it should not generally extend below the 12th rib. Stomach should be in that left upper quadrant, not squished, not displaced. Outside of that, look at the biogas pattern. Again, normal distribution of biogas, depending on when you shoot the film, the baby pops out and you shoot a film, there's not going to be a lot of biogas that's already been swallowed. So most of the gas will be very proximal. You may only see biogas in the small bowel. It takes, as I say, about 24 hours for biogas to get all the way through to the rectum. General width of bowel is about the width of the L2 vertebral body in a newborn. If you had to have a mark, if you say, is that bowel dilated with air or is it not? If you look at the L2 vertebral body, the height of the L2 vertebral body, not width, height of the L2 vertebral body, that's a pretty standard normal. So use that as a quick judge. If bowel is stacked on top of each other, always abnormal. The bowel gas pattern in a normal newborn baby is very polygonally shaped, and you should never be able to pick out an individual loop of bowel in the abdomen. They just look like polygonal air collections scattered throughout the abdomen. If you can pick out an individual loop in a crocantic fashion, it is almost always abnormal. So that's another simple point to look at if you're just briefly looking at it. Other things you're looking for, mass effect, soft tissue masses. You're not going to be able to often distinguish them, so you have to look for their secondary mass effect, and obviously calcifications. You should never see any pathologic calcifications in the abdomen. Look for the hip position as well, and bony pelvis. Is that about covering a KUB? Yeah. Does that answer the question? Anything else I can... Specifically in this patient, though, it is the spine, the heart, the position of the organs, situs, and calcifications. I mean, that's a good summary. Probably about as best you can get. Yeah. And important to look at the spine like in patients like this. And to calculate the sacral ratio, this kind of tells you how to do it. You can drop a line straight down the spine in the center. And then if you take perpendiculars at the iliac crest, at the lowest point of the sacroiliac joints and at the tip of the spine, you can create this ratio of BC, which is basically a degree of sacral hypoplasia. Is it normal or is it too short? And if you make that ratio in the frontal view, as Greg described, you often have a tilt of the sacrum, which kind of... If it is tilted a lot, it erroneously makes the BC seem too short. So that's why the lateral view is so helpful. You can draw a line down the axis of the sacrum, which you can see it is tilted, and you can draw the same lines actually perpendicular to that axis, the new axis, and do the same ratio. And usually the lateral view, I can't say it from literature, but the lateral view is much more accurate. And so this is the way you calculate the sacral index or the sacral ratio. And those two numbers at the bottom of each of those screens are the normal sacral ratios on both the AP and the lateral view. I had a question. Mostly we measure this sacral ratio in the newborn, correct? We do. We do. Exactly. From the radiology point of view, this ratio changes by the aging of the child or no? I say yes. Suppose you got a two-year-old. Well, that's the question, because you say, yes, we use the sacral ratio in a newborn presenting to your institution for the first time with an anal rectal malformation. The problem is we see so many redos here that are coming in from outside institutions that are varying age. And we get sacral ratios on all of them. I find it interesting in talking to Dr. Levitt. It's called sacral ratio. I don't, in the older patient, I don't personally believe it's a sacral ratio because you measure always to the most inferior ossified segment than you can see. If you have a normal sacrum, you're measuring all three coccygeal segments as well once they become ossified. So I do think there's some variance with age because it depends on what's ossified and what's missing. I think as a general rule, I think if you have five sacral segments, you're going to be pretty much normal. It really becomes more of a significant component when you begin to lose your lower half of your sacrum, S3 through S5. And you're talking about predicting, as Dr. Levitt talks about, one of the predictors for continence later on is what is that ratio. We use that ratio as a potential predictor. If you're particularly under 0.3, the likelihood of continence is very low. So somewhere in that range between 0.3 and 0.5, you know, I don't know exactly what percent in the literature those patients will be continent. But if you're up around 0.6, 0.7 or above, most of the time you're going to do fine in terms of your sacral ratio. But I have a little bit of, the wording sacral ratio always throws me a little bit because I'm always, in the slightly older patient, measuring coccyx as well. It's included in the ratio because it is the lowest ossified point that you can find. We're not measuring, and I say a three-year-old, the five sacral segments to use as the ratio. You are measuring the lowest component. And that's why I have a little bit of a problem with the wording of sacral ratio versus sacral cuspid geo ratio, depending on the age. For the surgeons on our panel, do you routinely calculate these ratios in your patients with ARM? And if you do, do you use them to prognosticate on continence with the families? We've recently started doing it because, again, there are a lot of things that are there are some data to suggest that it's the prognostic value of it. So, you know, it is definitely helpful to have that number. Also, you know, a lot of us, I think, in the past have eyeballed it as well. I mean, you know, it's what we've been doing up here is the sacral normal or abnormal. You know, adding a quantitative number to it is helpful. But, again, it's something we're just starting to do. Keith? I don't know. Yeah, I've always looked at whether or not you had intact sacral elements down through S3. If you're down through S3 and they're all intact and normal appearing, then I think the outcome is often good. I think the looking at the ratio is just part of that. Yes, the sacral ratio is more accurate and more objective to evaluate the size of the sacrum. And we use it every day with our patients. You know, especially as I think we're moving towards objectifying criteria for who has good potential for bowel control, this number will become very helpful and it creates a common language for all of us to speak as opposed to us saying, yeah, it looks good or it's not good or it goes down to S3 or, you know, the sacrum tilts a little dorsally. Did you just diss Dr. Jorgensen? No, no, I'm not dissing him. I'm just saying. He trained us. I'm just saying that we all have different definitions of what we consider to be good or not good. But once we all get on the same page as a community, we'll both, you know, when we were talking about standardizing care, looking at, it's going to give us that opportunity to do it if we can all say, okay, the sacral ratio is X, Y, or Z. And just to be clear, I think it's a good idea. Well, also remember, too, that it's not just the sacral ratio which really determines whether this patient's going to be continent or not. It has to do with the spine. It has to do with the tethered cord. There's a lot of other criterion that go into deciding that, a good repair, et cetera. As Dr. Levitt has said earlier, he's trying to come up with an arm index with four major components. You know, what does the perineum look like? What malformation do you have? What is the sacral index? And do or do you not have a tethered cord? Those four components, from my understanding in talking with him, are going to have a potential for identifying the patients who have future continents or not have continents, but also to compare between institutions. If at this institution, everyone below 0.4 on the sacral index is incontinent, but at your institution across the seas, everybody above between 0.3 and 0.4 is continent, then we're doing something wrong. Something is happening at our institution where you're doing a better job. So I think a common lingo amongst all institutions with repair and a common understanding of how to measure this and how to report that will help institutions compare how they're doing with the rest. And we should all try to achieve the same component. So I have a quick question for our radiology colleagues. So how do you standardize this amongst your colleagues in the radiology department? Because, you know, the people who are dedicated to doing it, they do it all the time, but then there's the ones, even though they may educate their fellow colleagues, don't routinely do it. So that's been one of our challenges. So I'm just curious about how do you guys build it into your standard work? So we do have a standard template built in for this on our PAC system. It's a standard voice dictation system. It's a standard template of what to do. Dr. Levitt has come and given us many morning lectures to reinforce that, and we reinforce it at new lectures on how to measure these. These come across as orders as specific. Dr. Levitt, sacral index. There is a very specific way of what is ordered and how it's measured, and everyone in our department, every radiologist in our department knows how to do that. And everyone is reported identically the same. The three measurements, it's parallel to the sacrum. And for non-colorectal patients, are you guys calling this out as well and say if you're reading a plain film with the AP lateral? No, we generally don't. We've built into the system that there are certain words in the clinical history which... So if ARN pops up... Correct, because the difference between an AP and a lateral view of the pelvis and an AP and lateral view of the sacrum are two totally different studies and done different ways. So our techs know, and it's built in throughout the system, that if you see the word Dr. Levitt and sacral ratio, it automatically falls into an AP and lateral pelvis as opposed to an AP and lateral sacrum. So anyone without that wording in our system will not get an AP and lateral view, a true AP and lateral view. And that's been reiterated over and over. It has to be that way if we're going to report these in the accurate measure. And hospitals that have a lot of patients coming through that are like this, as does ours and here at Nationwide, we do have those templates built for all... ...for radiographs, for MRI, for ultrasound, etc. I'd like to invite Brent Adler to come up here and join us on the panel. He was a... Because of the difference in timing, he wouldn't be able to be there, but he's here now. Welcome Brent, and we'll have some more things for you to comment on. The ratio of radiologist to surgeon. There we go, there we go. Equal it out. So here's how the lateral view is calculated. This is a patient who we saw earlier today. There's the lines that are drawn along the axis of the sacrum at three different levels. And of course, this one was 12 over 18, which is 0.6, which is a normal. And we had an interesting... Can you go back real quick? Sure. It's interesting on the lateral view at the level of the inferior most portion of the sacrum. Because we know from lateral chest, the side closest to the film is larger than the side furthest away. So when you take a lateral view of the sacrum, there'll be a side closer to the film and a side closer away. So one of the sides of the pelvis will be magnified compared to the other one. So never will you get a perfect overlap of the inferior SI joints. One will always be bigger than the SMAR. And I know Dr. Levitt made reference to this earlier. We have decided to pick the middle component between the two as our second line. So between the two. Between the two. Right. The average of the two, that's going to be our second. And if you see here, these are a little bit off. You can see that the femurs are not right superimposed on each other. And that would be your internal control. If these are not superimposed, then it's not quite lateral. And you do get that overlap. But he's 0.67 even with that. So why not? Sure. Just a small comment. From the level of evidence we were talking about before, there's just one study by Warren from London who studied the sacral ratios and looked at the inter-observer variability. And she shows that in the normal sacrum there's no variability. It's OK. But particularly in the abnormal sacrum, there is an amount of variability which makes the x-rays a little bit less valid. So this is a problem if you have three or four radiologists. It's not as clear in every picture as we think. But if you try to use the exact same technique as best we can, there's inter-observer variability on scoliosis films. We know that. At least, you know, 9 to 10 degrees on any film that you measure. Everybody's eye is slightly different. But the technique is as best you can with the film that you have. And we try. But this study was done in great armistice. They have good radiologists. They had very good pediatric radiologists look at it. And there was a... They could see that it was abnormal. But the ratio, the exact value, the number you give, is not as accurate as we think. I do think if we get a low ratio, it is, of course, you can do something with the prognosis. But I don't think the...I mean, it's not as exact as we think it is. That's the only issue. Yeah. It is not an exact science. That is true. Sorry, just a comment on that. We keep talking about how it's predictive, but it's never been shown to be predictive to long-term continents. We're studying that. There's not really good robust multicenter data. There's very few single-center data looking at that. So we're in the process of studying that. So here's an abdominal film. And also, again, there's an abnormal sacrum. Very often they have dysplasia. They have sacrums that are not symmetric. Not necessarily a hemisacrum, but just dysplastic. So this is an example of one of those. And just another example of a sacral ratio, which actually, if you count, there's the right number of segments, and it is normal. And the normal sacral ratio does vary significantly. It can be from 0.6 all the way up to 1. And again, it also varies depending on the positioning. So positioning is very important. And this one is right on. You can see there's really a superimposition of all the structures on the lateral view. And they have patients with almost a very, very little amount of sacrum below the SI joint here. So this is almost literally a zero on the frontal view. And remember, on the lateral view it may be a little bit more accurate because you can see this patient probably has a very slanted sacrum posteriorly. And this is a newborn. And in newborns you don't have the coccyx that's ossified. So the valid point, that is a valid point that in the newborn your sacral ratio may be a little different than in the older child. But again, correct me if I'm wrong, Brent and the surgeons, this is an estimate. Again, it's not a hard science. It's an estimate. When you have a sacral ratio that's below 0.3, you would assume that there are absent segments. And one of the things that we always, we were trying to toy with in Cincinnati is why isn't an ultrasound just as good as something like this? If you see on the ultrasound that there are only three segments, then clearly there's going to be an abnormality in the sacral ratio and it will be abnormal. So looking at the spine ultrasound to make sure that it is abnormal, is normal and that there are five sacral segments is a very good predictor as well. I suspect on this film too, this may have been shot as a crossfire lateral view because you can see air distending the rectum down to about the S3-4 level. So when do you acquire your sacral films? Do you shoot different sets of films or if you were getting a crossfire view of the abdomen in this situation and get a true lateral view, you could use this as part of your sacral study as well. At least a lateral view, not an AP view if you're looking for extent of air containing colon and distance from the anus. I'm not sure exactly why he had this in here, but I'm going to skip by this. We've seen so many examples. Now you can see other anomalies. Absence of the lumbar, almost from the lumbar all the way through the sacrum, so-called caudal regression. So you can see there's complete fusion of the iliac wings and absence of the lumbar sacral spine for the most part. No fusion of the lower extremities. This patient will have an obvious smile anomaly on MRI as well. These are the same patient frontal and lateral views. This is what we saw before. And as you can see here, it looks like there's an absence of the sacrum below here. But as you see, there is some here. There is some sacrum. And actually the sacrum ratio in this patient is borderline, probably on the borderline side. So what about the cross table lateral x-ray? The surgeons, when do you get cross table laterals on patients in the newborn period to decide when to do a colostomy? If you ever use it. Do you ever use it? I mean, I personally have moved away from it. I mean, you know, after 24 hours, if we're not seeing meconium at the bottom, usually those will deserve a diversion. Unless they have like a really well defined and developed perineum, and you have suspicion that there might be a low-lying rectum, then in those instances I might consider it. But it's, we've moved away from doing it where we used to do it before. It didn't really change our practice, so we stopped doing it. Are you talking about the prone cross table? The prone cross table. Yeah. I still use it because it's easy to get and it gives me a little more information. So I think it's helpful, although I think what was pointed out this morning is sometimes you can get meconium jammed in the distal rectum and you can be confused by that in terms of how close to the skin it is. It looks like the OR is ready. Okay. We need to go back live. So I think we're going to pause on our discussion right now. Come back to it after this. So we were talking a little bit about the cross table lateral view and when to do. How about a vote about the surgeons in the room? A, get a cross table lateral in very clinically unclear cases of what to do. So clinically it should be apparent when to get a colostomy and when not to get a colostomy, but sometimes those clinical markers are not present. And that really is the time to get the cross table lateral view, this so-called invertogram. And at least in our practice, it's about 5% of the time. It's really not very often at all. And there are some pitfalls as we described earlier. So A, do we have a person who's a, oh here we go, great. So A, I use the cross table lateral. B, I don't use the cross table lateral. And here's an example of it. So let's see what the survey said. So we use a cross table lateral about two thirds of the time. So some people still rely on this and I think it actually is a good way to do it. This is the way it's done and of course there is that bird's beak or that twitter appearance that you see here and the patient who has a rectum that's fairly far away from the BB which is denoting the area of the anal sphincter. So this is the way we do it. We put the patient prone. But remember too that you really can't do this and get an accurate knowledge or an accurate representation of where that distal rectum really is unless you do this after 24 to 36 hours. Because you really have to have enough time for some of the air to develop and cause pressure to build up and show you that that is the true level of the distal rectal pouch. I think that's very similar. I think that's very, are we on? We should be on. I think it's very similar to looking for meconium on the perineum. You have to give it 24 hours. And same with the cross lateral view. You have to have enough pressure to get air all the way down to the colon in order to do that. What number do most people use to think, well the question is on these inverted grams, can you do primary repair or do you do a stage repair? I may not be using those terms appropriately, but can you not have to do an ostomy? And when can you go in and do a primary? What level or what closeness to that marker, that BB, do you feel comfortable doing a primary repair in an inverted gram? So our panelists. Well it depends. For me, it's not a precise number. Anything that's within a centimeter I think you're very safe to do. But then you have to look at the perineum. If there's no fistula, then I think you have to be very careful. Unless it truly is close. About one centimeter is kind of what we would use radiographically. The question is, how many people are using inverted grams versus how many people are actually using perineal ultrasound? So A, B. A? At your institution, do you tend to use ultrasound or do you tend to use cross table lateral radiographs? A, ultrasound, B, inverted gram. Is there an option for both? Are they usually? Got to make a commitment. No, no. Only now. Only now. Dr. Levitt didn't leave us with a C. What I would like to know though is, how do they compare? Do you feel the ultrasound is more reliable than say this cross table? Well, having done several of the ultrasounds, but also not garnering a lot of support from the surgeons, because I don't think that they saw the value of them. I personally believe the ultrasound is more accurate. I think I'm right on the perineum. I don't have to worry about the position of the BB. I don't have to worry about air. And in several instances, I can actually see the fistula to the urethra. I think, personally, I'm in favor of the ultrasound. I just don't think, I don't think that this particular test or the ultrasound by itself is a measure, you know, has a measurable difference. I think it's, as you say, the clinical features of the perineum and the patient. So, it would be nice if pediatric radiologists developed a protocol that could then be disseminated so that it could be a valuable tool to all of us. I agree. You know, we've approached Mark about doing ultrasound. A lot of his patients are beyond that point when they get to us. So, we haven't, he hasn't voted in favor of it. For example, right now, a protocol is out there for the use of ultrasound for appendicitis, for example. And, you know, it's very specific and very helpful. And if you had something like that, then I think it would become much more commonplace in practice. I agree, and I agree with Dr. Krauss about using ultrasound to look at the sacrum. And I think, you know, you would get a one-stop, no radiation exam to look at the sacrum, count the segments, look at the quality of the segments, look at the position of the cord, and look for a mass. One of the questions, though, to me is, you know, how often is this actually going to change what you're going to do? Right. Because, I mean, even if a perineal fistula was identified, there are many surgeons that don't feel comfortable doing a primary repair in the newborn period. I'm not saying that people necessarily hear, but a lot of people aren't going to feel comfortable with that. So, who's going to feel comfortable taking a kid to the operating room in the newborn period to do a primary PSARP when there's no perineal, there's no meconium present at the perineum. So, you know, I think this crowd here is a very sophisticated crowd, so we're talking about this. But even in those instances, I don't think a lot of times this study is going to change what you're going to do in many instances. So, if I have a strange looking perineum and a fistula, I often will cannulate that fistula and ask for a little gastrographin or some water soluble to be put in there. Is that valuable to you? I mean, how do you view that as a cardiologist? Well, personally, having done that on a few patients that have come down with what I think is a small dimple and gentle probing with a 24-gauge angiocath, I have popped through very easily a small, simple membrane, and then I inject water soluble contrast and descend it out and show the anatomy. So, similar to you, I think, looking at the perineum, making a very clear judgment on whether you think it's a low... Because the point is, we don't want to bungle into the urethra, particularly in the male. If they have... And we also want to avoid the complications of a colostomy, which are many. If you do a colostomy, the incidence of complications doubles in that patient. And so, we'd like to avoid that, but again, we want to be safe. Right, and I guess what we need to do is identify the patient who you would do the primary repair on and determine if we're giving you enough information. And I don't think we know that. And I would be... I think most radiologists would be pleased to have a protocol and have a multicenter study to see if we were allowing you to predict the future. Yeah, there is literature, and there's some literature on ultrasound, and ultrasound is pretty good. And there are some really elegant articles from Europe showing that you can see the fistulae, etc. The problem is, a lot of times, the ultrasound timing... When you do the ultrasound, it's the same thing as the plain film. Because if you don't have distension there, it's going to look like it's a really far distance. And if you have distension with air and with fluid, then it's going to overcome that rectal sphincter. Because when the sphincter is closed, there's a big gap. And when the sphincter is open and distended, it's going to be much shorter. So it really is timing. And if you wait 24 to 36 hours, you can do either technique, and you're going to be able to see it. Ultrasound is very elegant, but you have to have the experience. It's an experience thing. So, I mean, I think ultrasound is a lot of potential, but there has to be centers that want to do it. And you have to vary the standard technique, as we talked about. You can't put too much pressure on the perineum. The baby has to be quiet, so they're not valsalving, because your distance measurements are going to be off, etc. So it has to be a very specific thing. Steve? And are you doing that in prone or lithotomy? I've actually done it in lithotomy. Just before you ask the question, this is a patient who has what looks like a higher or a patient with a rectourinary fistula, most likely if it's a boy. Here's a patient who has, at the same kind of timing, 24 to 36 hours, a marker marking the anus. And you can see the rectum coming all the way up, very close to the anal sphincter. And same here. But look at this case. Not this one, but this one. And look at this one. This one, actually, is the case I wanted to show. This is a patient from Italy. It was Dr. Pena's patient. He tells the story all the time about this very important person. Of course, it was a doctor's son who was born, and they got the radiographs. This radiograph was done right after birth. And as you can see, the rectum comes way, way above the so-called pubococcygeal line, which they actually drew on this film. And so they said immediately, oh, this is going to be a patient with a high or a relatively complex malformation. So they got a colostomy. And this patient, in fact, there was no meconium. There was no meconium at the tip of the penis. There was no meconium at the perineum. But when they did the colostogram, when Dr. Pena got there to help out with the repair, the colostogram showed a perineal fistula. It went all the way down to the perineum. So what happened was this film was done at a couple of hours of age instead of waiting the 24 to 36 hours. So that's the pitfall. If you do these tests too early, then you're going to erroneously think that it's a higher or more, a higher rectal pouch, when indeed it could be very, very far down towards the perineum. So as far as waiting is concerned, there was an article recently in the Journal of Pediatric Surgery about perforations that occur if you wait too long. Right. And what is too long? This journal article suggested it was 48 hours. Yeah. So the recommendation for this is 24 to 36. Certainly you can't wait too long. Absolutely. Your question? Well, we're just going to, we're talking a lot about the decision of whether to do an anoplasty or a colostomy. Right. And I think that there are a lot of young people in the audience. And if you don't see meconium on the perineum and you're just getting started, you don't want to do too many blind perineal explorations. Sure. It would be very encouraging if there's an invertogram that looks really low. I mean, I think that's a really rare film. Right. Honestly. I'm sorry, it's the same film. So I don't think that that happens. Well, actually, this is a different, this, yeah. It's actually, in practice, I can say in the last several years, I've seen a couple. Yeah. A couple. With no meconium on the perineum. With no meconium on the perineum. Yeah. So it's pretty unusual. It's, yeah, it's not very common. So, I mean, you might occasionally see an x-ray like that and then maybe you'd get an ultrasound to see if you can prove that there is the rectum really close to the perineal skin. And in those cases, I did one where there was no meconium and I did the bad thing of putting a needle in because it looked so much like, where's the fistula? It looked, the perineum looked so normal. And I think you want to select your patients very, very carefully. But I don't think we should give people the message that just because there's no meconium on the perineum, you should go searching for it and if you think you see it, do a perineal exploration. I think that's the wrong message to send. Yeah. And I think it's never wrong to do a colostomy if you're unsure. And that's probably the message that we should leave. Over, there's a question. One more question here. Again, these are selected cases. We don't do, we do not do invertegrams in most patients. The one special situation is the Downs patient. And I've had, I think, three in the last couple of years. They just, they came, they come in waves like that. But three girls who, who did not have a perineal fistula. But we did these, I usually do both. And had evidence that the rectum was very close to the perineal skin. So when, you know statistically because they're Downs that they are much more likely to not have a fistula than have a fistula. So, so those three kids managed without a colostomy. Where without those studies to reassure me that, that it was a very low rectum, they would have ended up with a colostomy. And the ones with Down syndrome that we've seen, that I've seen personally, have, some of them have been very, very close. But some of them have been kind of, especially in boys, sort of at the level of the ball bar urethral level, but without a fistula. And in those, it might not be so easy to get from the perineum to them. So. I think, you know, this is just one of many tools that's potentially to take into the armamentarium. Physical exam, clinical history, and some very quick imaging that may give you an idea. You know, I think one of the possibilities, if it's very, very low, it may give you some reassurance. But if it's high, I don't think you can be 100% predictive of whether it's low or not. I think that's probably the best take away message. So, distal colostrograms. Distal colostrogram is probably one of the most important tests, especially in boys, to get prior to your definitive repair. And so here's a couple of examples of distal colostrograms. And if you want to comment on some of these, Greg. Sure. So these are two views from my lateral colostrogram. Some important things you want to look at. A, we cannulate the ostomy. You want to inject from a very proximal point. You don't want to put your Foley catheter way down into the rectum, because the surgeons are going to want to know what the length of the remaining colon is. Number two, you need to pressurize the colon. And sometimes these take a lot of pressure, and you think you're going to rupture it. Injecting these. The thought going in is that, in general, as Dr. Levitt has said previously, that outside of Down syndrome, the large majority of patients have a fistula. 95% in general. So your goal is to try and demonstrate that. And you need to feel comfortable that you've pressurized this to the point that you've actually seen that. The ones that don't have fistulas, I think when it's fully pressurized, if you look at the inferior part of the rectum, it is completely spherical in my experience. Look for that beak. If there's a little tiny beak coming off the base of that rectum, that points to where the fistula is going to come off, and you've got to try and demonstrate that. Can you get impacted meconium down there? It's possible. Most of it floats away. But feel comfortable administering contrast. You don't want to walk away not having pressurized this colon and saying there's no fistula. It's your job to demonstrate the fistula, if it's that common. Pressurize it enough. Look for that little fistula. Look for the contrast to extend into either the proximal or distal urethra. Obviously, there are four types we've talked about already. If it's recto-bladder-neck, the ones I've done with recto-bladder-necks, you put in the contrast, it immediately fills the bladder. There's almost no resistance to filling of the bladder. It fills almost immediately. The recto-prostatic and the recto-bulbar fistulas, it depends on how narrow the fistula is, but look for a thin amount of contrast, filling the prostatic and the bulbar urethra. Once you've done that, there's always been some discussion, do you continue on and try to fill the bladder and do a VCUG-type exam from that point. I have found that relatively difficult in the lower fistulas. When they're high in the bladder neck, it's relatively easy to extend the bladder and get them to void and show more or less a voiding view. And look for reflux if it's present. At this institution, I said we do a combination. I tend to do the high-pressure colostogram first, demonstrate the fistula, take the contrast out of the rectum, and generally catheterize them from that point and do the VCUG concomitantly to satisfy our urology colleagues and get answer of both. Sometimes the fistulas are very minimal or very poorly demonstrated. Sometimes doing the VCUG and seeing a little dimple, you can match up and you can get a fairly accurate position of where you think the fistula is. Other things to obviously look for is look at the sacrum and look for any evidence of a presacral mass. So those are kind of the four things to look for. But the key is making sure that you have very good pressure and you have a good length of colon there for the surgeons. So this is a, looks like a recto, probably prostatic. Right, and when you see this, as you said, when you see this little extension here, almost like a beak, there's going to be a fistula and it's just your job to demonstrate it. Can I have an A and B? In A, radiology does the colostograms and B, the surgeons do the colostograms. Let's see what they, let's see what people do here. Good, so most, a lot of radiologists do them, but the surgeons do them too. And so this is important when you see these, when you see a little nipple here, there's going to be a fistula. If it's all nice and round and you don't see this, then it's most likely that there's not going to be. But again, 95% of boys are going to have a fistula approximately. So it's your job to show that. And it's always important on this lateral view to include the full sacrum on the view. Because as Dr. Pena has, or Dr. Pena, Dr. Levitt has said, you want to see the relationship of where the fistula is in relationship to the very tip of the sacrum. So that, you don't want to cone too much, you want to include the full sacrum on that view. Here's an example of a colostrogram as well, a really large distal segment. And you can see again, a very, actually a more narrow fistula and a longer one that is going into the region of the prostatic urethra. Certainly if you see that bend in the urethra, Mark likes to use that bend as a junction of what may be prostatic and bulbar. I don't think on these studies that there really is a good radiologic correlate where the bulbar urethra starts and the prostatic urethral tissue ends. It's very difficult to tell. And I think a lot of times when it comes to that bend, I'm a little bit more prone to say either a low prostatic or a high bulbar. I think it is very difficult to tell in all honesty. Any questions? Is this a VCUG or...? No, this is a... I'm sorry. I guess this is a... I think this is a high pressure colostrogram. This is a high pressure colostrogram. The problem is... Actually the catheter in the ostomy. There's a catheter in both. You can't see real well because it's so dark, but the catheter is coming in here. When I see a colostrogram like that, my fingers start itching like crazy because it's such a nice case to do laparoscopically. Yeah. Oh, and also these are actually more at risk. When you get a really big distal clonic segment like this that's really patchless, these are ones that are more prone to perforate. And that's because of Laplace's Law. When they have a really big dilated segment and you put a lot of pressure on it, the wall gets very thin. And of the patients who had perforation, there's about three in our series. One of them had a really big patchless segment like that. So I think you have to be very careful when you're injecting them. You know, this also illustrates another point though, and that is that just because you see a narrowing, you shouldn't stop dissecting. You want to keep dissecting until you get down to the T where it goes in. Because if you tied that off high, you'd leave a little diverticulum, which you don't want to do. We'll show some examples of those where they cut off a little too high and you get a diverticulum. How was those three perforations during your colostagrame management? So I can only comment on one of them because it's the one that happened to me. And it was one like this where we just showed the fistula and right after the fistula was shown, the segment perforated. And it was with a contrast that was a little hyperosmotic. It's called cystoconrite. It's the same kind of contrast we use for cystograms. But it's important because the osmolality of that contrast is about 400 milliosmoles as opposed to the body fluids. And so when it got into the peritoneum in which it flooded the peritoneum, the patient actually went into extremis. I mean they were fluid shifting immediately and the patient's only three months, four months old. So their body fluids are limited. And so I brought him right to the emergency room and he got IV fluids right there and the surgeon was called. And basically the patient went right up to the OR to get fixed. So it's not something, it's not a moot point. It's actually a very, it wasn't a very comfortable situation. But as soon as it did happen, I knew it happened. I have a slide that I don't have here, but I have a slide. The whole peritoneum is filled with contrast. It's a nice invertegram of the liver and the spleen and all the other organs. Okay. But realistically, those patients have to be managed immediately because of the fluid shift and the peritonitis and their heart rate shoots up. It's not a moot point. It has to be managed immediately. I'm interested in how you might manage that. I mean these are diverted patients. One of my thoughts might be to just suck out all that contrast and then see what happens. I'm not sure you need to operate on that patient unless it's a huge rent. In any event, the patient did well. The patient did fine. But it is not one of those situations where you want to just kind of let them sit there for a while. We took them right to the ER. The other thing too is the contrast agent we use now where we are is a isosmotic contrast. As a result of that, we changed. And we use a contrast agent that's very dense, but it's isosmotic to body fluids. So if it were to get into the perineum, there would not be any fluid shifts. It's a change in practice that resulted from that. In any event, this is another colostogram. And as you can see here, there's a flattening of the rectum. And there is a little bit of a nipple there. So there is, and there's a little bit of contrast going through. But you can see here the segment isn't very well distended. So if you distended more, you'd be able to get more contrast into the urethra, into the bladder, and then show exactly where the connection is. I suspect that if the bladder neck is here, this is probably more of a ball bar, but it could be pretty close. Comments? No, it looks like a barium study. Just the density of that contrast. Yeah. I'm not sure what Mark wanted to show by this, but I think what he wanted to show was getting the picture in the frontal view also gives you an idea of the length. Because in the lateral view, you may superimpose all this, and it may look very short from year to year. But when you get the frontal view, you can see how long it is. And actually, this one is plenty of length to mobilize and bring down to the anus.
