A referral is not a commitment to surgery
A DBS evaluation is a structured conversation and assessment. It gives you and the specialist team a clearer picture of which symptoms might improve, which may not, what the risks are and whether another treatment may fit better.
You can complete an evaluation and decide not to proceed. The team may also recommend waiting, adjusting medication, trying another advanced therapy or gathering more information.
Asking for a referral means you want informed options. It does not mean you have agreed to brain surgery.
Three situations when asking may make sense
An international Parkinson Study Group panel reached consensus that people with a well-supported Parkinson's diagnosis should be considered for DBS evaluation when one of these situations is present:
- Troublesome motor fluctuations or dyskinesia interfere with daily functioning or quality of life despite optimized medical treatment.
- Disabling tremor remains uncontrolled after an adequate levodopa trial, even without motor fluctuations or dyskinesia.
- Levodopa produces a clear benefit but cannot be tolerated even at low maintenance doses because of significant side effects.
The panel also warned against delaying or denying referral based only on age, disease duration, Parkinson's stage or a single movement-test score. Those factors matter, but none should decide candidacy by itself.
It means DBS should be discussed when meaningful motor complications appear, not automatically saved until every other option has failed or medication no longer works at all.
Why medication response matters
DBS most reliably improves motor symptoms that improve when levodopa is working, such as rigidity, slowness, motor fluctuations and dyskinesia. Tremor can be an exception because some medication-resistant tremor may still respond to DBS.
A medication-response assessment helps the team compare your movement when medication is not working with your movement after levodopa. The amount of response is useful information, but the consensus recommendations say it should not be the only candidacy test.
A whole-person evaluation
A responsible evaluation looks beyond movement. It should include neurological, neurosurgical and neuropsychological assessment, along with a direct discussion of your goals and your family's expectations.
| Area | Why it belongs in the conversation |
|---|---|
| Cognition | Testing helps identify strengths, impairment and individual risk. There is no single evidence-based cognitive score that decides candidacy by itself. |
| Mood and behaviour | Depression, anxiety, hallucinations and impulse-control problems require careful assessment and may need treatment before surgery. They do not all automatically exclude referral. |
| Speech and swallowing | DBS is unlikely to improve speech, and speech can worsen with stimulation. Existing speech and swallowing concerns should be documented before surgery. |
| Gait and balance | Freezing may improve when it responds to medication, remain unchanged or rarely worsen. Balance usually does not improve reliably, but balance problems do not automatically prevent DBS for other motor goals. |
| Apathy and other non-motor symptoms | These should be measured before surgery and monitored afterward, but they are not primary reasons to pursue DBS. Medication changes after DBS may also affect motivation and mood. |
| Support and follow-up | Surgery is followed by programming, medication adjustments and recovery. The team needs to understand what support is available and what the care partner needs. |
Turn hopes into specific goals
“I want to feel better” is real, but it is difficult to measure. A useful goal connects a symptom to life: “I want fewer unpredictable off periods so I can make lunch safely,” or “I want enough tremor control to use a keyboard.”
Ask the team to place each goal into one of three groups: likely to improve, uncertain, or unlikely to improve. That helps uncover hidden expectations before surgery rather than disappointment afterward.
Build my DBS conversation sheetQuestions to bring to your specialist
- Which of my symptoms make you think an evaluation is or is not appropriate now?
- Which symptoms improve when levodopa is working?
- Which of my goals could DBS realistically address?
- How might DBS affect my speech, swallowing, balance, cognition, mood or apathy?
- What alternatives should I compare with DBS?
- Who would be part of the evaluation and what tests would I complete?
- What would make your team recommend waiting or not proceeding?