After 10 – 15 minutes, almost all of the radiation should be in the bladder.
The gamma camera takes readings every few seconds for 20 minutes.
The computer adds up the radioactivity in each kidney and the bladder.
This can be shown as a graph of activity versus time – a time-activity curve.
A Normal Renogram
An Abnormal Renogram
Radiation not only kills cells, it can also kill germs or bacteria.
Nowadays, medical instruments (e.g. syringes) are prepacked and then irradiation using an intense gamma ray source.
This kills any germs or bacteria but does not damage the syringe, nor make it radioactive.
Ionising radiation is used in radiotherapy to treat cancer and to sterilise medical equipment because it destroys cells.
Radioactive tracers are used in nuclear medicine because the ionising radiation it emits is easy to detect.
There are 3 main uses of ionising radiation in medicine: treatment, diagnosis and sterilisation.
Radiotherapy is used to treat cancers by irradiating them with ionising radiation.
Radioactive tracers are used to diagnose and investigate several medical conditions.
Ionising radiation is used to sterilise medical equipment as it kills germs and/or bacteria.