Stereotatic radiosurgery for the treatment of motor symptoms in Parkinson's disease: A systematic review

Stereotaxic Radiosurgery (SRS) is a non-invasive lesioning technique for movement disorders when patients cannot undergo DBS due to medical comorbidities. To describe and summarize the literature on SRS's application and physical parameters for Parkinson's disease (PD) motor symptoms. The MEDLINE/PUBMED and EMBASE databases were searched in July 2022 following the PRISMA guideline. Two independent reviewers screened data from 425 articles. The level of evidence followed the Oxford Centre for Evidence-Based Medicine. Pertinent details for each study regarding participants, physical parameters, and results were extracted. Twelve studies reported that 454 PD patients underwent Gamma KnifeⓇ (GK). The mean improvement time of the treated symptoms was three months after GK. Tremor is the most common symptom investigated, with success rates ranging from 47.5% to 93.9%. Few studies were conducted for caudatotomy (GKC) and pallidotomy (GKP), which presented an improvement for dyskinesia and bradykinesia. Physical parameters were similar with doses ranging from 110 to 200 Gy, use of a 4-mm collimator with an advanced imaging locator system, and coordinates were obtained from available stereotactic atlases. GK thalamotomy is a good alternative for treating tremor; however, its effects are delayed, and there are cases in which it can regress after years. The outcomes of GKC and GKP seem to be promising. The existing studies are more limited, and effects need to be better investigated. La radiochirurgie stéréotaxique (RCS) est une technique de lésion non invasive alternative pour les troubles du mouvement lorsque les patients ne peuvent pas subir de stimulation cérébrale profonde (SCP) en raison de comorbidités médicales. Décrire et résumer la littérature sur l'application de la RCS et les paramètres physiques pour les symptômes moteurs de la maladie de Parkinson (MP). Les bases de données MEDLINE/PUBMED et EMBASE ont été consultées en juillet 2022 en suivant la ligne directrice PRISMA. Douze études ont rapporté que 454 patients atteints de la maladie de Parkinson avaient subi un traitement par scalpel Gamma (GK). Deux examinateurs indépendants ont passé au crible les données de 425 articles. Le niveau de preuve a été déterminé conformément à l'Oxford Centre for Evidence-Based Medicine. Les détails pertinents de chaque étude concernant les participants, les paramètres physiques et les résultats ont été extraits. Le délai moyen d'amélioration était de trois mois après l