A cystogram is a radiology procedure to examine the bladder. The procedure is performed by a radiology doctor with the help of a technician. The procedure involves placing a catheter into your bladder while you lie on the X-ray table. The bladder is than filled with contrast. The procedure will usually take under an hour. It is safe with few complications. Allergies to contrast dye, urinary tract infection and pregnancy are a few contraindications.
X-ray pictures are than taken as the bladder is filled. Sometimes pictures will be taken while you empty your bladder as well. The bladder will be filled until it is full. I usually fill the bladder until the patient has to void. I will take pictures while you turn to both sides and flat. I also take X-ray pictures as you void.
X-ray pictures are taken, with attention to the bladder and ureters which drain into the bladder from the kidneys. If the ureters have contrast in them, than this is called reflux and is abnormal. I also look for anything inside the bladder like a mass or stone. In some cases, we are looking for leaks. A leak will mean that the contrast in the bladder will be outside the wall.
Some common reasons to do the test include urinary reflux. This occurs when urine goes into the ureters. This can happen while filling the bladder, emptying it, or both. The urine can go as high up as the kidneys. Patients with reflux may have frequent urinary tract infections, scarring of the kidneys and even loss of function.
We do cystograms when we look for leaks either from trauma or after surgery. Leaks will be seen as contrast extending outside the bladder wall. The contrast usually increases over time. The exact site of the leak can also be identified. Leaks of urine can also be diagnosed with a dedicated CT. This can be a less invasive means of diagnosis since no bladder catheter is involved.
I rarely do cystograms for bladder polyps, stones or masses. On cystogram, these will look like filling defects. That means that there will be a defect in the white contrast throughout the bladder. Cystograms will not be as good at telling what a filling defect is compared to CT or cystoscopy. A cystoscopy is done by a urology doctor. He will look directly at abnormalities and can biopsy.
Cystograms are done to look at the bladder. It is better than CT for some indications like reflux since we can observe in real time. Most commonly, I see this test being done for reflux and bladder leaks. CT has replaced many prior indications. Cystoscopy done by a urology doctor is also a common test of the bladder which allows direct visualization and biopsy of abnormalities.