What are the possible side effects of CT scans?

Because CT scanning uses x-rays to obtain pictures, you will be exposed to some radiation which you would otherwise not receive. However, the dose of x-rays used for the screening CT scan is less than you normally receive in a year from the natural surrounding environment and the risk of it causing harm is therefore very low. If an abnormality is detected, you may need follow-up CT scans and if lung cancer is strongly suspected, further tests will be required. The radiation dose for follow-up CT scans would be higher than for the first but the risk is still low and the benefits of detecting lung cancer at an early stage must be considered.