Editorial. An ethical framework for deep brain stimulation in children.

Deep brain stimulation (DBS) is increasingly considered for the treatment of refractory neurodevelopmental conditions affecting children.25 In 1999, Coubes and colleagues were among the first to report on the use of pediatric DBS for primary dystonia.9 Since then, pediatric DBS has gained considerable traction, with several case series reported.25,29 Although dystonia remains the most common indication for pediatric DBS, the technology has also been applied to treat epilepsy44 and Tourette syndrome.38 More recently, DBS of the nucleus accumbens and amygdala have been reported for self-injurious behaviors.34,41 The majority of the evidence for DBS in children has been derived from the adult literature, in which the procedure has been shown to be safe and effective for an increasing number of indications.37 However, pediatric DBS has many substantial differences, with important bioethical, social, and legal considerations. First, patients and their caregivers represent a uniquely vulnerable population. Second, given biological differences between adults and children, the procedure in pediatric populations can be considered a surgical innovation and is still investigational for all indications. Third, the natural history of a disease within the context of a child’s neuromuscular and cognitive development must be factored into treatment decisions. Furthermore, the surgical risks and technical nuances of DBS differ from those in adults. Thus, evidence from the adult DBS literature may not be readily translatable to pediatric populations. With the exception of DYT1 dystonia (for which there is level II-2 evidence45), all indications for DBS in pediatric patients are in the early stages of investigation; thus, the procedure represents a surgical innovation, i.e., a procedure that “departs in a significant way from standard or accepted practice.”11 Surgical innovations are characterized by evolving techniques, outcome measures, and patient selection.31 Three systematic reviews and metaanalyses (two manuscripts currently under review and one paper in press10) have described the conduct of DBS in pediatric populations (Table 1), all emphasizing significant heterogeneity and the need for prospective studies to guide patient selection. The framework we describe here is intended to be applied to DBS in children in all settings, most of which are presently experimental or under the realm of surgical innovation. Ultimately, the most basic ethical principles protecting research subjects flow from the Nuremberg Code (1948), the Declaration of Helsinki (1964), and the Belmont Report (1979); however, in children with a medically complex condition who may benefit from novel investigational treatments, a more targeted framework is needed.11,14,43 Herein we expand on differences in the conduct of DBS between adults and children and the unique ethical challenges they pose. First, we describe ethical issues raised by the vulnerability of the patient population, the novelty of the application of DBS for expanding indications in children, and the conduct of the procedure in children despite limited evidence. We then propose a bioethical framework for the evaluation of children for DBS. Although ethical issues may figure more or less prominently depending on the individual patient and the indication, the framework we put forth may be generalized to shape personal, institutional, and social policies regarding DBS in children. It is not our intention to prescribe the steps and thought process for carrying out pediatric DBS, but rather to advance dialogue regarding the ethical underpinnings of this promising technique in children.

Field of study: Medicine