Discussion
The rapidly evolving field of cranial nerve stimulation and neuromodulation techniques has the potential to revolutionize the management of Parkinson’s disease (PD). In this review, we have critically assessed the latest advancements in non-invasive and minimally invasive approaches, their clinical applications, and the evidence supporting their safety and efficacy. These innovative techniques offer the possibility of more targeted, less invasive, and better-tolerated treatment options for patients with this debilitating disorder [30].
Non-invasive techniques, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), have demonstrated promising results in alleviating motor and non-motor symptoms of PD [31, 34]. Repetitive TMS (rTMS), in particular, has shown consistent improvements in motor function and gait, with some studies also reporting positive effects on mood and cognition [35]. The advantage of these non-invasive approaches is the absence of surgical risks and a relatively low incidence of side effects. However, the long-term efficacy and optimal stimulation parameters of these techniques are yet to be determined, and further research is needed to establish their role in the clinical management of PD [32, 36].
Minimally invasive techniques, such as vagus nerve stimulation (VNS) and trigeminal nerve stimulation (TNS), have also shown potential benefits in the treatment of PD. VNS, a well-established treatment for drug-resistant epilepsy and depression, has been increasingly investigated for its effects on motor and non-motor symptoms in PD [25, 37]. Although preliminary studies have suggested a favorable safety profile, more extensive research is needed to confirm its efficacy and establish optimal stimulation parameters. Similarly, TNS, a novel neuromodulation technique, has demonstrated encouraging results in early studies on motor symptoms, sleep, and cognition in PD patients, but further investigation is required to validate these findings and define its role in PD treatment [28, 39].
Despite the promising results of these emerging cranial nerve stimulation and neuromodulation techniques, several challenges remain to be addressed before they can be widely adopted in clinical practice. One critical issue is the need for well-designed, large-scale, randomized controlled trials to determine the long-term safety, efficacy, and cost-effectiveness of these approaches, particularly in comparison with existing treatments [38]. Another challenge is the identification of optimal stimulation parameters and individualized treatment protocols, which could maximize the therapeutic benefits and minimize potential side effects. This will likely require a better understanding of the underlying neurophysiological mechanisms and the development of advanced computational models and personalized stimulation algorithms [40].
In conclusion, next-generation cranial nerve stimulation and neuromodulation techniques hold great promise for the treatment of Parkinson’s disease, offering the potential for more effective and better-tolerated alternatives to current pharmacological and surgical therapies. However, further research is needed to address the existing challenges, optimize treatment protocols, and validate the long-term safety and efficacy of these innovative approaches. As our understanding of the neurophysiological basis of PD continues to evolve, these novel technologies may pave the way for more targeted, individualized, and comprehensive treatment strategies, ultimately improving the quality of life for millions of patients affected by this debilitating disorder.