[MUSIC] Hello, my name is Diane Reyes, I'm a nurse practitioner at Johns Hopkins. I take care of men with metastatic prostate cancer and in addition to that I participate in the research activities in Dr. lab and in his clinical practice. I would like to welcome you to my talk about Imaging in Oncology. I'll be presenting Lecture number 5 in the series, introduction to cancer biology. And that will be about how imaging is used in the management of patients with cancer. My objectives for you at the end of this lecture will be able to understand the orientation of imaging views, and that you'll be able to describe the major types of imaging. That you'll be able to list the ways imaging are used in the management of cancer and finally that you'll be able to explain how imaging supports a new theory which is oligometastasis. So we'll begin with a brief introduction to imaging. I would like to define medical imaging. Discuss a little bit about how imaging is oriented so that you can understand the view that's taken and I'll talk about density and contrast media. When we talk about imaging, what we actually mean is medical imaging, and that's defined as the technique and process of creating visual representations of the inside of the body for clinical analysis, and medical intervention. Or, more simply, it's to take pictures of the inside of the body, and one or two, diagnose, and treat disease. Here, we see an image on the right which is a chest radiograph which is a representation of the internal anatomy what you see on the left. Imaging orientation does important so that you can understand the view that's taken. The first consideration is whether or not you are looking at a two dimension image or a three dimension image. On the left, we see an example of a two dimension image. It's a plain radiograph. And what we see in those images are the length and the width of structures. And that would be in comparison to a 3D image, which is seen on the right, which is also called a cross sectional image. And here you see length and width, and as well as depth so that allows you to see the relationship between structures. In this slide, we're looking at the most common projections that you would see into the imaging. On the left, you'll see a schema of what we call a PA projection. You have the X-ray tube, and out of the X-ray tube is the X-ray beam, and it comes through the patient from behind, or the posterior, and the beam exits the anterior side of the patient. Which is termed a PA view. And what that means is when you actually look at the completed product, it'll be in reverse. It'll be as if you were facing the patient. So the heart, which we know is on the left, will appear on the right on the image. The other common projection that is taken in two dimension images, is the lateral view which is seen on the right and then in that position we're just looking at a side view. And a lateral chest X-ray is shown on the right-hand side. And then, next we're going to talk a little bit about 3D image projections which are also called cross sectional imaging. And that’s what we tend to see most of when we look at images now. The 3D image projections are based on the anatomical planes of the human body. We have, first of all, the transverse plane, which separates the head from the feet. It is also called an axial view. And then, next, we have the frontal plane, which is also termed the coronal. And the frontal separates the front from the back. And then, lastly, we have the lateral view, which is also called sagittal, and that separates the right from the left. Here, we have an example of an axial or transverse view of the body. It was taken at the mid chest level, and it's separating the head from the feet. So noted here, I have labeled the lungs, and the lung on the right, we see that a mass is pointed out. However, we need to remember the images on reverse so the mass is actually in the left long. Also, noted are several bones. We can see the sternum on the top of the image and the spine is in the bottom and then to the right and left the spine we see the scapula and the ribs. Here, we have an example of a coronal or frontal view of the abdomen. It's separating the front from the back of the body. So on the left side of the image we see the liver and the gallbladder, and then on the top right-hand side we see the spleen, also noted are several bones. You can see the spine and the ribs and the hips. And then, finally, we have an example of a sagittal view of the body which is along the lateral anatomical plane, separating the right from the left. Starting at the top of the image we can see the heart and the the liver and kidney, bowel and bladder. And then, we see the spine along the right-hand side. We've talked a little bit about how to understand the view of the image. Now, we want to talk a little bit about density. The reason why we can see different structures of the internal anatomy is because they have different thicknesses. So bones are the thickest tissues. Therefore, I know the most dense, so they'll show up. White on the images, and then thin tissues like lungs that are filled with air, are less dense so they show up as dark. And then, the soft tissues in the body like the heart, and the great vessels, and the abdominal organs that are pointed out here. They're moderately dense, so they look gray on the imaging. On the left, we have a PA view of the chest. And on the right-hand side, we have the axial view of the chest taken at the level of the dotted line on the PA test. And something to notice on the axial image is that the vessels that are close to the heart, are showing up white, similar to the bones. So normally since they're soft tissue they would be the same as the heart. And they would not be standing out so much. The reason why they're standing out, is because they have been enhanced, which is what we're going to talk about next. On this slide, I'm showing you a contrast agent. So when we want to differentiate structures of similar densities, we use contrast agents, also called contrast media, or it's simply known as X-ray dye. And the contrast agents, they are usually given orally or injected through a vein or an artery. And the more common X-ray dyes are iodine and barium. On the left, we have a picture of a radiograph of the abdomen, and X-ray dye was given through a vein in order to enhance the urinary system. So you can see the outline. It's a little bit difficult to appreciate, but you can see the outline of the kidneys and the ureter and the bladder. In the middle image, again, we have a radiograph of the abdomen, but this patient was given a different type of contrast media. This patient was given barium to drink, and that has enhanced the stomach and the small bowel, which are pointed out. And then, on the right, is an axial view of the abdomen. This patient was given both oral and IV iodine contrast so that allows us to see almost all the soft tissues of the abdomen. We have here pointed out the colon and pancreas, the aorta, and the kidneys. When we come back, we'll be talking about the different types of imaging.
