Exploring New Horizons in Treatment: The Potential of Radiation-induced Neuromodulation to Enhance Psychological Therapies in Refractory Obsessive Compulsive Disorder

Abstract

Obsessive-compulsive disorder (OCD) poses a significant challenge in psychiatric treatment, with a considerable number of patients exhibiting limited response to conventional therapies. As a result, neuromodulatory and neuroablative approaches for treatment-resistant OCD are gaining popularity. Stereotactic radiosurgery (SRS) presents a minimally invasive neuroablative approach that targets specific brain regions and has some advantages over other neuromodulatory strategies. This narrative review examines the promise of radiosurgical neuromodulation, focusing on Gamma Knife SRS. Due to its non-invasiveness and excellent focal precision, SRS neuroablation techniques have drawn significant interest for the treatment of refractory OCD, mainly when targeting the anterior limb of the internal capsule through a technique referred to as capsulotomy. Capsulotomy studies have shown encouraging results for treating refractory OCD, however, most of them report the risk of severe adverse effects such as development of brain cysts related to higher radiation doses. Thus, the concept of radiation-induced neuromodulation with repeated lower, sub-ablative doses is explored in this paper. Additionally, Personalized Ultra-fractionated Low-dose Stereotactic Adaptive Radiotherapy (PULSAR) is introduced as a novel radiotherapy approach to combine with SRS capsulotomy for achieving radiation-induced neuromodulation without neural tissue ablation. Based on a careful evaluation of literature evidence, the historical growth and improvements in psychiatric radiosurgery are highlighted, emphasizing the possibility of noninvasive, radiation-induced neuromodulation approaches in modulating aberrant brain circuits in treatment resistant OCD. The key impact of this research is to provide a strong foundation for creating future protocols designed to test the effectiveness of PULSAR-induced neuromodulation-assisted psychological treatment for refractory OCD patients.