What should you know about SBRT for the brain?

Brain SBRT delivers carefully focused radiation to a selected brain target while limiting exposure to nearby healthy tissue. It is planned from detailed brain imaging and may be considered when a target is small, clearly defined, or difficult to reach with surgery. The suitability of treatment depends on the target's position, size, number, symptoms, previous treatment and overall health.

A planning scan maps the target and nearby structures such as the optic nerves and brainstem. A treatment machine, often a [Linear Accelerator](/technology/linear-accelerator/), sends radiation from several directions so the beams meet at the planned target. The treatment team checks positioning carefully at each visit. SBRT is a form of [Stereotactic Body Radiotherapy](/treatments/radiation-oncology/stereotactic-body-radiotherapy/), although the brain may be described separately from treatment of other body sites.

You may have a mask or another positioning aid to help keep your head still. Radiation itself is not felt, but the planning process and lying in one position can be tiring. Effects may include temporary headache, nausea, scalp irritation, tiredness or swelling around the treated area. Your team may prescribe medicine if swelling is a concern.

Bring a current list of medicines and tell the team about seizures, blood-thinning medicines, implanted devices and any previous brain treatment. Ask whether you should take your usual medicines on treatment days, arrange transport, and plan for rest afterwards. Follow instructions about food, fluids and steroid or anti-seizure medicines. Follow-up scans are used to assess the treated area and guide the next decision; imaging changes can sometimes need careful interpretation rather than an immediate conclusion.

Contact your oncology team promptly for worsening headache, repeated vomiting, new weakness, increasing confusion, a seizure, new vision or speech changes, or difficulty staying awake. Seek emergency help for a seizure that does not stop, sudden severe weakness, or a sudden loss of consciousness. Do not stop prescribed steroids or anti-seizure medicine without instructions, because abrupt changes can worsen symptoms.

Ask what the target is, why SBRT is being considered, what nearby brain structures need protection, how many visits are planned, and which symptoms should trigger a call. You can also ask how prior surgery, whole-brain treatment or medicines affect the plan, and when your next scan will be reviewed.