A radiotherapy planning CT scan is slightly different to a regular diagnostic CT scan. It allows radiographers to obtain 3D images of the area being treated in order to create individualised radiotherapy plans.
The scan itself will normally take between 10 to 15 minutes. However, sometimes there may be additional preparation for your scan which can mean that the appointment may last up to 2 hours. A few patients will require an injection of a contrast agent (IV contrast) and some patients will need to drink a liquid before the scan (oral contrast), these help highlight important areas the doctors may want to treat or avoid.
During the planning procedure, measurements will be taken for your radiotherapy record. During this process it will be necessary to place small marks, on your skin using a felt tip-type pen. At the end of the process, these marks will be made permanent, with your permission, by tattooing a small dot. This is so that prior to and during treatment you will be able to wash as normal without losing the marks.