LAUSR

Deep brain stimulation (DBS) is a well-established treatment for movement disorders. Recent industrial competition has led to unprecedented new technologic implementation. Nextgeneration implantable pulse generators (IPGs), henceforth defined as FDA-approved devices after 2015, include Abbott InfinityTM, Boston Scientific Vercise GenusTM and Medtronic PerceptTM. These IPGs provide enhanced technical capabilities, and may be inter-compatible with old Medtronic DBS leads (“hybrid” systems). Several case series have demonstrated safety and utility of such hybrids. However, there are technical nuances that may not be immediately apparent. Additionally, there are DBS systems yet to be FDA-approved, including PINS and SceneRay in China, as well as CE-approved Newronika and Aleva. This letter focuses discussion on the decision strategy in selecting the best FDA-approved replacement IPG in patients who hitherto have in-situ DBS systems. Abbott and Boston Scientific have independently manufactured IPGs that fit Medtronic extension wires 37085/37806. Devices manufactured before 2010 (pre-ActivaTM), however, employed Legacy extension wires (7482/7483/7495), which are only compatible with Medtronic (via adapter 64001/64002) or Abbott IPGs (with/without adapter). The Boston Scientific B26-adapter for legacy extensions is not currently FDA-approved. Abbott and Boston Scientific devices are not inter-compatible with each other. Therefore, it is important to note the initial system that was implanted to determine hybrid-compatibility. Another consideration is the overall MRI-conditionality of the system, which is determined by individual DBS components. While MRI checklists are often used, special attention should be paid when an adapter is required as this often results in loss of fullbody MRI-compatibility. An exception is the Medtronic-Boston Scientific hybrid system using a 15/55 cm M8-adapter (full-body 1.5 T MRI-conditional). Additionally, when consolidation of bilateral to unilateral hardware is desired using a dual-channel IPG, this may require trans-sternal routing of extension wire, which is currently only head-only 1.5 T MRI-conditional using a full Medtronic system. The need to re-site IPGs to new locations may also form large loops (eg, transabdominal routing) which loses MRI conditionality due to electromagnetic interference. To further strategize the decision process, we leverage the strengths of each device. Of the predefined next-generation IPGs, only Boston Scientific offers rechargeability. Rechargeable IPGs offer compelling advantages, including increased longevity (at least 10–15 years), reduced surgical complications, and overall longterm savings. They are better poised to support novel programming strategies where energy requirements remain undefined. However, patients with limited social support or cognitive obstacles may not be suitable. All next-generation IPGs allow low pulsewidth (<60us) stimulation, which expands the therapeutic window. To further optimize stimulation, devices utilizing independent current control (Boston Scientific and Medtronic Percept) for precise current shaping may be considered. Anodic stimulation is also possible in Boston Scientific IPGs. Local field potential (LFP) sensing capability (Medtronic Percept) may allow practitioners to correlate LFP changes to clinical status in an effort to optimize therapy. Abbott offers the only FDA-approved synchronous remote tele-programming system (NeurosphereTM Virtual Clinic). This may benefit patients who live afar or are homebound. Other remote-capable DBS systems (PINS and SceneRay) are currently only available in China. Figure 1 illustrates a simplified decision workflow in consideration of the above factors.