As new hardware options emerge for deep brain stimulation, medical providers specializing in DBS have a growing responsibility to understand similarities and differences in order to provide patients with adequate information to make an informed decision about device selection prior to surgery. Device companies are one source of information about safety, proper implantation technique and use. Clinical experience is another source of knowledge to weigh the options.
Medtronic (Minneapolis, MN) is the first device company to develop DBS systems with thousands of implants providing benefit to people world-wide with FDA indication for Essential Tremor (1997), Advanced Parkinson’s disease (2002), dystonia (2003), Obsessive Compulsive Disorder (2009) and early Parkinson’s disease (2016). St. Jude Medical (Minneapolis, MN) has recently gained FDA approval for their DBS system with indication for Parkinson’s disease and Essential Tremor (2016). Boston Scientific (Marlborough, MA) is a third device company to develop a DBS system presently with approval for use in Europe. Refractory Epilepsy is under consideration by the FDA per Medtronic news release.
The FDA provides approval for use based on safety and research data. Reaching beyond FDA approval and implanting other medical conditions outside of FDA approved research studies would be equivalent to experimentation at the expense of the patient.
Benefit is measured by control of stimulation responsive symptoms while avoiding side effects while extending battery longevity, the tenants of stimulation therapy. If probe position in the brain is adequate, stimulation delivered via hardware systems noted above are known to be effective. No implanted device has shown superiority in benefit nor avoidance of side effects or reduced risk of complications. Medtronic completed research and safety testing in order to gain conditional FDA approved for brain or body MRI. Differences do exist in programming options, patient control and battery longevity, topics for another blog post.
New Issues & Threats to Patients
Mixing hardware systems has already surfaced as the latest threat to a patient seeking to improve benefit beyond what is possible, eliminate side effects or improve battery longevity. Patient beware of claims that are too good to be true as no one device is superior and mixed systems are potentially inferior as device compatibility, efficacy and safety is not known. When mixing device parts, efficacy, technical and mechanical specifications are without technical support which leads to uncertainty when troubleshooting. The FDA has not approved mixing implanted devices from different device companies and therefore considered experimentation, a situation that would break down medical ethics in treating patients.
Replacing hardware is not uncommon when systems break or misplaced in the brain. However, the evaluation to determine whether more surgery is safe or indicated requires a medical and surgical team experienced in the highest level of surgical targeting, surgical awake testing and device programming to minimize possible harm to patients. Additionally, the situation where both probes are misplaced is very uncommon and complete system removal and re-implantation is rare.
With new systems comes marketing and promotional strategies to grow market share. When positive pressure from competition remains outside the operating room, all stake holders can benefit in moving the development of neuromodulation therapy forward. However, removing a DBS system with the goal to implant a different and better DBS system or claims of superiority in reducing symptoms cannot be justified. Most common question I hear is how can a patient know if a surgery is reasonable. Best answer is to seek a second objective opinion from highly trained and experienced DBS experts.