The two kidneys are shown by the upper arrows. The bladder is at the lower arrow. The urine reached the kidney by flowing backwards. Once the tube is in place a salt-water solution and radiopharmaceutical mixture is administered via the tube into the bladder. If reflux is present, the monitoring device, a gamma camera, can detect it.
Computers make it possible to determine the degree of reflux as well.
While similar tests are available in diagnostic radiology, the amount of radiation administered to the patient may be 100 times that administered during a nuclear medicine examination. Because of the low radiation dose children can be monitored periodically to see whether the reflux is resolving spontaneously. No specific patient preparation is required. The patient is not required to perform any particular maneuvers during the examination. It is often beneficial for the patient and parent to remain together during the study.