A CT dosage plan is usually performed as a preparation for all radiation treatment. For stereotactic irradiation towards brain metastases MR of the brain is performed additionally. When cutaneous metastases is being treated with electrons, the field set-up is often marked directly on the patient`s skin.
During CT dose planning it is important that the patient is optimally treated for pain and is able to remain still in a supine position. Premedication may be given. Extra dose of opiated may also be necessary.
Before the first radiation treatment to the brain, a customized plastic mask is made for the head to immobilize the patient.