Radiologic studies, or special pictures to image the urinary tract, are an integral part of the hematuria evaluation. These studies allow us to see the structure, or anatomy, of the kidneys, ureters, and bladder, giving us information as to the cause of the blood in the urine. These pictures are able to demonstrate tumors of the urinary tract, inflammation, outside masses pressing on the urinary tract, stones, as well as give an estimate as to how well the kidneys are working.
A plain x-ray of the abdomen is used to look for stones in the kidneys and ureters as well as stones within the bladder. It can also show the presence of foreign bodies in or around the urinary tract, as well as evidence of prior surgery.
Abdominal x-ray showing oval white density to left of spine--stone in left
ureter.
An intravenous pyelogram is an x-ray of the abdomen taken after an iodine solution is given intravenously to a patient. Iodine is excreted by the kidneys and appears white on an x-ray. So, if x-rays are taken several minutes after the iodine is given, the kidneys, ureters, and bladder will light up white against the black background of the x-ray, and we will be able to see the anatomy of the urinary tracts. Since most stones show up white on an x-ray, their exact location in the urinary tract can be established on an intravenous pyelogram. Masses that distort the normal anatomy of the kidneys and bladder can be visualized. A filling defect, which is an area of the urinary tract that should fill white with iodine but does not, may be suggestive of a tumor.
Iodine seen in dilated left kidney. Dilation comes right down to stone in
left ureter.
Round shadow on right side of bladder later shown to be a bladder cancer.
A CT (computerized tomography) scan is an x-ray that a computer interprets in such a way as to give a picture of the inside of the body as if we were seeing slices of the body. An analogy is slicing a loaf of bread and looking at the individual slices. We are seeing a cross-section of the body at different levels. This radiologic study is especially helpful if a mass is suspected to be causing the blood in the urine, as the relationship of the mass to the various internal organs can be appreciated. There are also certain types of stones, uric acid stones, that cannot be seen on a plain x-ray but are easily visualized on a CT scan
Mass in left kidney later shown to be a kidney cancer.
An ultrasound, or sonogram, is a picture taken using sound waves. It is used frequently in children to image the kidneys. In adults, it is most often used when a kidney mass is suspected on an intravenous pyelogram, but the nature of the mass is not known. An ultrasound can tell us whether this mass is solid, which is suggestive of cancer, or made up of fluid, which is suggestive of a cyst.