Deep brain stimulation is a complex treatment that requires time and attention beyond the typical medical appointment, especially when there are DBS problems. Decisions about stimulation changes are based on patient reporting of symptoms, medication dosing, examination and reporting from the care partner. In some circumstances, I also use brain imaging as a factor when selecting stimulation settings. The following data is helpful to have when adjusting stimulation and I frequently ask my patients about most of these at each appointment:
- Three day symptom diary that includes the time of each medication dose.
- Medication list that is accurate in how medications are taken. (This may not match how the medication was prescribed)
- Pre-surgical work up including symptom testing or examination off and on medication.
- Brain imaging.
- Time-line from the patient’s perspective that includes benefit, side effects, problems. (Critical to sort out problems)
- All past stimulation settings and corresponding effects. (Some of my patients keep a running list of settings and response)
- Comprehensive notes from the care partner or home video of symptoms.
- Open discussion about sources of stress that may interfere with or hinder benefit from stimulation.
- Reporting of other unrelated medical problems, new medications or non-prescribed substances.
- Lastly and potentially the most important is the patient’s comments on how things are going and if not going well, what could be the source of the problem.
Read about an unusual second opinion from my troubleshooting files.
Case Study (from my troubleshooting files)
A new patient was seen for a second opinion about a funny sensation on their scalp and occasional tingling, heat sensation and minor shock-like sensation in the neck. The person had been having the sensations for about 6 months and told several times by their programmer that nothing was wrong and to ignore the sensations. On review of the history, the person had DBS for about 6 years and had experienced a very good outcome. Lately, tremor had been showing up in the hand occasionally and when the tremor came on it was quite bothersome and then would go away. Medications and general health was unchanged over the past year. There was one wedding and one funeral, but no undue stressors that persisted. No falls, no new hobbies and the Parkinson’s was otherwise stable. The stimulation had not been changed over the past year and the electrical checks were reported to be normal.
During the exam, the person did not have tremor and the stimulation appeared to be working properly. Touching the wires gently did not reproduce any shocks. The skin over the wires and battery was well healed. The electrical system check was normal. The person also appeared to be taking adequate medication. Based on the patient’s reports of odd sensations and occasional breakthrough tremor, I ordered a complete set of x-rays to examine the wires.
The x-ray was conclusive. The wire insulation was damaged and needed replacement surgery.
The main learning points from this case example is the patient knew something was wrong. Following the historical information can solve most DBS problems in one or two appointments. The odd sensations were very near the damaged wire and a simple x-ray revealed the problem. The wire was not completely broken so stimulation could still travel down the wire, but some of the electrical current could leak out into the tissue and cause tingling, heating and minor shock sensations. On more discussion, the patient’s care partner remembered a bump of the head several months ago.
The outcome of the second opinion: We replaced the damaged wire and the person regained good tremor control and no longer experienced odd sensations.
This story is one example from hundreds of patients I have seen for troubleshooting DBS problems. Most people (about 60%) require only a change in their stimulation settings. Hardware problems are not common (about 10%) but can cause a decline or loss of benefit that can be restored after an accurate diagnosis.