The Role of Dual Energy in Pediatrics is Fine

I'm intrigued by the title like Dual Energy CT is fine. I'm not sure if it's a question or if it's fine, but we're going to find out so we will start with dual energy and the pediatric patient. We've heard a lot about drill energy this morning and the applications in children or pretty similar, but it's a great tool and I'll show you why. Since moving. There we go, so I'm going to discuss the clinical experience in a Children's Hospital and then review a little bit about the radiation exposure. Our experience started in four of fall of 2014 and we had a flash at that time were actually getting a for sometime this summer and the pediatric side an A number of forces. I just found out maybe 10 on the adult side so we'll have a lot more experience to share with you. I think so far at least done 2000 plus dual energy CT's. Probably more than that for Neuro Siti dual energy CT is or default for routine contrast and non contrast exams. In body see T. It is our default an contrast examinations and also a non contrast renal stones CT. So the workflow and this was on the flash, but it's going to be similar on the force is we look at the 80 KVP the blended and then we send over a 50K EV to increase contrast. An increased lesion detection. We don't really use the 1:40 in children very much. So one of the applications I think these are the key applications. Bone removal is fabulous son to energy. See T so it's great for contrast enhanced CT and see T angiography, lung blood volume and lung perfusion is terrific in the chest. Will look at that monoenergetic imaging you've heard about and primarily in children. It's fabulous for artifact reduction. An then iodine mapping for tissue characterization. So let's start with some of the applications and will start with bone removal first. It's big impact, particularly in neuro radiology and contrast enhanced examinations an it's really gotta roll in a valuation of the areas of complex anatomy. The neck in the skull base, and I think we talk a lot about low dose. But we've also got to recognize that image quality is a big part of what we do into energy, ECT. Allows us to have both great image quality and low. Dose in evaluating the brain and the neck or doses are lower than the standards by the American College of Radiology. So here we have one example. I think you can see that with the skull still the bone still present. You can see the vascularity but once we remove the bone it's really easy to see the vessel so it increases your confidence, not necessarily with sensitivity sometime but your confidence in the ability to detect the lesion, the seat drive all here was 15.4 milli Grays and the American College of Radiology reference value. By the way, 4 head CT is 35, so we're staying well below the reference value. This is a neck, a CTA. It's a 14 year old girl who had neck trauma and syncope. So the issue was did she have a vertebral artery injury and with the 3D rendered image there? If I use it since working here we go. You can see the vessels and the vertebral artery. You don't really get a. Clearview of it. But once we remove the bone, it's easy to see the vessels. There's a little narrowing of the vertebral artery but its patent in this patient does not need further intervention. So when it comes to head and neck, CTA bone removal is fabulous. In the chest, I think the advantage of dual energy CT is really lung perfusion. You can use. We use it for everything, but were you going to do some postprocessing is in lung perfusion and the major applications. Congenital heart disease, particularly the post operative repair in patients who have pulmonary absence or pulmonary agenesis, pulmonary artery absence. We use in pulmonary embolism, but it's not as commonly used as it is an adults, so everything we do address is a clinical question, and when it comes to congenital heart disease, the issue here is the surgical shunt. Is it patient because patients who have absence or a hypoplastic pulmonary artery get surgery and are the lungs perfused? One thing you need to know in children is that the reference values are not the same as in adults, so the default maximum CT number of 600 -- 600 Hounsfield and adults won't work in children, particularly young ones. Their lungs are denser, so you need to decrease your default 2 -- 200 to minus 300, otherwise you'll get false perfusion defects, and if you look here and I think you can see the numbers of minus 100 to minus 600. You want to do something around minus 200 to minus 300 Hounsfield units they profusion is fairly homogeneous once you get higher, you'll notice a number of defects in the lungs that. Mimic a profusion defect, and they're not real there. An artifact in younger children. So case 1 four month old status post surgical shunt for treatment at absent pulmonary artery OK. This patient had a let's get that. Here we go. Maybe not there we go had a shunt with the superior vena cava going to the pulmonary artery. OK, first question is that patent and you can see the superior vena cava hooking up with the pulmonary artery on the CTA. So its patent. But the real issue are the lungs perfused X Hillview. Here's the shot. There is some narrowing of the pulmonary arteries an on the profusion image. The right lung is perfused. The left lower lobe is perfused in the left upper lobe has decreased perfusion, so this patient needs a stent, so dual energy CT has really had an impact for us in assessing congenital heart disease. 12 year old boy. Same issue absent pulmonary artery. Now he is surgery is superior vena cava, inferior vena cava hooked up to the pulmonary artery. the CTA inferior vena cava, superior vena cava hooked up to the pulmonary artery. So first thing the shunts intact. Second thing, his lungs are incredibly well perfused. There's a little defect in the right middle lobe. It's not significant. This patient does not need further intervention. So for lung perfusion, just like in adults, this is terrific. Different application, congenital heart disease, and at a very low dose one pulmonary embolism. You saw a lot this morning, same and children 13 year old girl with right chest pain. She has a pulmonary embolism protocol. And she has PE on the right and she had some pulmonary embolus on the left and you can see on the profusion that she has some scattered defects in the lungs. A large defect here. Here is an infarct, the Hamptons hump, few defects there. She's going to be treated anyhow, but this gives the clinician. An idea of how significant this disease is and our job is to communicate with the physician. So this is important information. In the abdomen, number of rolls, but I think the important ones again, or CTA, particularly the bone removal ability of dual energy CT characterizing lesions. We do renal stones with CT. I won't review that because it's the same as in adults, so six month old girl with hypertension. An one of the causes of hypertension in children is narrowing of the aorta aortic Cork tatian. This is a 6 month old who was not sedated. We did a CTA. The vessels or normals. Nice example and you can see the renal arteries. We remove the bone. The aorta is normal, branching is normal and you can see the renal arteries. This patient does not have corrugation very easy study to do and provides incredible information to the clinician. This is a 5 month old boy with the same history. An in this case, here's the order and it tapers just below the superior mesenteric artery and the iliac vessels. Are incredibly small, so this patient will need some type of a bypass graft, but the thing about dual energy, it provides additional information so we can look at the iodine map and see that the kidneys have flow to them in their normal. Lesion characterization one example 7 year old boy with bone marrow transplant complicated by a trapping hemoglobin. An in this setting. The two things that concern us is is this. Just there's a lesion there? Is that a hematoma or is this patient developing a second malignancy, which can happen in immunocompromised patients. So you see a solid mass. We strip the iodine virtual non con. It's high density and then on the iodine map it has no flow. So we can increase our confidence that this is a hematoma. And this is one of my favorite cases. Some of the group is probably seen this, but it's a 9 year old girl with severe abdominal pain and she had an ultrasound and there was a large mass there and it was difficult to really interrogate the whole mess. So we did a CT and here is a huge bowel loop that is an incest inception. This is the lead point which was a hammer Toma an on the. Iodine map there's no flow that was totally ischemic bowel. An interception with ischemic bowel. You will notice normal flow in some of the small valves. So this is a very good technique. It's not necessarily going to increase your sensitivity, but the ability to make a specific diagnosis can be altered with dual energy CT, and it can increase your confidence. Mono energetic imaging is fabulous and it can improve contrast, but major advantage is artifact reduction as we've heard, but our artifacts are different in Pediatrics. We see a lot of scoliosis, and as you know, scoliosis is repaired with rods and nails, and that's a problem to image and we need to know if the rods in the correct place, an if there any complications, such as a loosening around the rod or infection. 15 year old boy with dual energy CT and at 140 KVP routine. It's difficult to know exactly where those nails are in the vertebral bodies. There a lot of artifacts. If you use your monoenergetic imaging and a high K EV, you can really see the rods in the screws very well and you can do your 3D rendering and strip all the bone away and get great images of the rods. So we did a study to see which K EV level was best for viewing the spine an we sort of graded it from one severe artifacts to four no artifacts. We did subjective reads and we did regions of interest and I think you can see here. The bottom line is if you choose a dual energy CT OK EV around 1:30 or 1:20. And call higher. You're going to really reduce those artifacts and you can see the spinal cord. So this is a Jenna fabulous tool for artifact reduction. Well, I'm going to keep us on time and the last issue is what's the exposure? So we did this. The one of the first articles on dual energy, CT and radiation exposures. I did this with Juan Carlos. She's one of the Siemens people we looked at 79 children. We did to energy see T and we compared it to cure cavey an auto MA we. Estimated that the console before we scanned and we found that the see T dose index and the size specific dose estimate were really comprable or lower with dual energy CT. As you can see by the numbers. OK, so we were even getting less radiation exposure and our conclusion was in pediatric body CT the use of dual energy CT results in radiation exposures that now are great equal to or less than single energy. So it's become our default study in Pediatrics. So in conclusion, the new energy ECT does not require additional radiation dose compared with conventional imaging. Image quality is maintained an it really is the you know that duo is what we need is one thing to reduce radiation. We're getting much lower, but we've got to maintain image quality and we couldn't do that with dual energy CT. So bottom line, it's a win win scenario, so thank you.

90keV Impact of Lung PVB threshold: Dose: Results Dual-energy CT of the Pediatric 12 year old boy with absent main 5-month-old boy with hypertension Monoenergetic Imaging Pulmonary Embolism Conclusion From -100 to -600 HU 6 month old girl hypertension AJR 2016; 207:1-10 Patient 2017: How I Do It Marilyn J Siegel, MD, Juan C. Ramirez-Giraldo, PhD 9-year-old girl with severe abdominal pain 79 children (12 days to 18 years) Mallinckrodt Institute Of Radiology DECT scans vs CARE kV (Estimates) Monoenergetic Imaging Marilyn J. Siegel, M.D. SIEMENS .. disease Washington University School of Medicine Mallinckrodt Institute Of Radiology Mallinckrodt Institute of Radiology CTDI and SSDE were comparable or lower with DECT Washington University School of Medicine st. Louis, MO -100 HU -600 HU -300 HU 150keV Healthineers st. Louis, MO St. Louis, MO Pulmonary Embolism (mGy) (mGy) Washington WVashington CTD1v0115.44 mGy DECT 3.7 5.9 < .01 University in St.lIouis University in St.louis Uniwersity in St.louis University in St. Inui s Bone SCHOOL OF MEDICINE SECT 4.4 7.5 HU MIR of Iodine Map CTD1v016.10 mGy CTD1v0115.44 mGy CTD1v011.44 mGy CTD1v010.61 mGy CTD1v01 0.61 mGy CTD1v016.610 mGy CTD1v010.610 mGy CTD1v010.614 mGy I-year-old CTD1v011.24 mGy SIEMENS .. CTD1v012.32 mGy CTD1v012.14 mGy CTD1v016.14 mGy CTD1v012.10 mGy Healthineers