Book Review

Neuromodulation techniques have rapidly transitioned from “experimental” to “accepted” to ultimately becoming an essential and commonly used modality in several fields; examples include deep brain stimulation for Parkinson's disease and essential tremor, transcranial magnetic stimulation and electroconvulsive therapy for depression, and spinal cord stimulation for chronic pain. Epilepsy would seem to be a prime candidate to join the neuromodulation revolution as a disease with a great deal of morbidity and mortality, and for which medications are often ineffective or cause adverse effects. What is the state of brain stimulation in epilepsy? How effective are different approaches in decreasing seizure frequency and improving quality of life? By what mechanism do the available therapies work? In Neurostimulation for Epilepsy: Advances, Applications, and Opportunities, the authors set out to answer the above questions and many more. The text represents a comprehensive overview of the past, present, and future of the use of neuromodulatory techniques for the treatment of epilepsy in a rapidly evolving landscape. It covers each available modality in depth including mechanisms, history, efficacy, and practical considerations and serves as both a literature review and potential reference resource given the large number of cited sources across the work (some chapters have 200+ sources). The book is organized in an intuitive fashion, starting with the physiology of brain stimulation techniques at the level of the neuron up to the network with a focus on neuroanatomy and the technical aspects of different techniques. This chapter is followed by another providing further detail on the technological background of the available devices and the underlying principles surrounding neural interfaces. These background chapters are important for anyone new to the field of brain stimulation but can be skimmed for those already working in the field. The overall approach to teaching this essential information is clear and straightforward. The book is weighted towards the implantable brain stimulation methods, allocating a full chapter to each currently available invasive modality, covering vagus nerve stimulation (VNS), responsive neurostimulation, and standard deep brain stimulation (DBS), as well as epicranial cortical stimulation. Each chapter is very comprehensive and covers the development and rationale for each treatment, results of landmark trials, current literature, future directions, and how the device is used in clinical practice. There is a single chapter dedicated to the non-invasive techniques including transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), transcranial auricular VNS (taVNS), trigeminal nerve stimulation (TNS), and transcranial focused ultrasound stimulation (tFUS), again comprehensively covering the history and evidence behind each technique and the most up-to-date research. Following this is a chapter with insights which have been gleaned from the long-term data collected by these devices and how this has been used to inform therapy. The penultimate chapter charts future directions in the field, with the concluding chapter focusing on quality of life and the effect of these devices on neuropsychiatric symptoms including cognition, depression, and anxiety. Overall, the book is approachable and easy to read. The chapters are written by leaders in the field with varied styles, and while this is occasionally slightly distracting, overall the different authorship does not significantly impact readability. The authors do sometimes repeat information especially at the introduction of a chapter, but this is typically brief and additive to the overall message of the chapter. Figures and diagrams are prolific and helpful to illustrate key points. One critique would be that while individual chapters cover each available therapy in depth, there is no chapter to “tie them together”; the book could benefit from outlining clearly which patients would qualify for which treatment, to contrast risk/benefit analysis between treatments, or to offer case examples of potential patients’ steps towards getting these therapies, including what diagnostics may be needed prior to qualifying. This textbook would be of use for readers from the level of trainee to fellowship-trained epileptologists. It provides an excellent overview of the current state of the field, and in practice it may be particularly useful to the clinician for data on average seizure reduction, risks, and benefits of treatment. It can either be read straight through for a comprehensive look at an important discipline in epilepsy management, or chapters can be read individually as reference material to answer specific questions. While it is no substitute for fellowship training and the experience of interdisciplinary evaluation of complex epilepsy patients in a dedicated refractory epilepsy conference, it serves as an excellent primer to the available possibilities for these patients with abundant resources for further self-study. After reading this text, it becomes clear that not only are neuromodulatory techniques increasingly (and appropriately) considered for patients with epilepsy given their favorable side effect profile and efficacy, but that epilepsy has joined movement disorders, pain, and interventional psychiatry as fields which have found brain stimulation techniques invaluable and irreplaceable tools, becoming the gold standard of care for select patients. As the fields of both epilepsy and neuromodulation continue to rapidly develop, Neurostimulation for Epilepsy will likely remain a useful resource for years to come. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The author would like to thank Dr. Mark George for his helpful suggestions during the writing process.