by Dr Antonella Macerollo
Our research paper of the month for October 2002 is Deuschl G, Antonini A, Costa J, Śmiłowska K, Berg D, Corvol JC, Fabbrini G, Ferreira J, Foltynie T, Mir P, Schrag A, Seppi K, Taba P, Ruzicka E, Selikhova M, Henschke N, Villanueva G, Moro E. European Academy of Neurology/Movement Disorder Society – European Section guideline on the treatment of Parkinson’s disease: I. Invasive therapies. Eur J Neurol. 2022; 29:2580-2595. doi: 10.1111/ene.15386. PMID: 35791766.
The fast development of new invasive therapies to treat Parkinson’s Disease (PD) raised the unmet need to have updated guidelines available for general neurologists and general practitioners taking care of PD patients. Therefore, the EAN and the Movement Disorder Society-European Section (MDS) joined together in delivering guidelines dedicated to the invasive therapeutic pathways for PD, including deep brain stimulation (DBS) and brain lesioning with different techniques, as well as continuous delivery of medication subcutaneously (apomorphine pump) and through percutaneous ileostomy (intrajejunal levodopa/carbidopa pump [LCIG]). The international panel of experts highlighted the heterogeneity in evidence for these invasive procedures since some of them (i.e., magnetic resonance imaging–guided focused ultrasound surgery [MRgFUS]) are relatively recently applied to PD, being more explored in other movement disorders.
Deuschl et al. confirmed that DBS of subthalamic nucleus (STN) continues to be the most studied and the most effective intervention (improving motor symptoms and QoL) for advanced as well as early PD with fluctuations without satisfactory improvement on oral pharmacotherapy. Of note, it should not be offered to PD patients without fluctuations.
GPi-DBS can be considered in advanced PD and it showed similar outcomes to STN-DBS. However, the opportunity to significantly reduce the l-dopa intake following STN-DBS was considered an important clinical difference that should allow STN to be prioritised as a target in PD.
LCIG and apomorphine pump can be considered for advanced PD with fluctuations not responding to oral treatments.
The most innovative part of these guidelines is the section dedicated to MRgFUS, which is a technique first developed for essential tremor. Deuschl et al stated that PD with unilateral motor symptoms might be eligible for unilateral MRgFUS of the STN but only within registries, whereas PD patients with mainly medication-resistant tremor can be considered for MRgFUS of the thalamus only within registries
Lesser used techniques such as unilateral radiofrequency thermocoagulation of the pallidum for advanced treatment-resistant PD and of the thalamus for resistant parkinsonian tremor can be recommended only if other options are not available,
Gamma radiation is not recommended by our international panel.
Further studies and, thus, further guidelines will be necessary in the near future to establish the definite role of MRgFUS in the treatment pathway of PD, since important questions are still open. In addition, infusion therapies are in rapid development with less-invasive interventions that need to be investigated in multicentre trials. Lastly, the use of DBS for psychosocial impact and non-motor symptoms in PD, as well as the possible usefulness for axial abnormalities, still need to be answered.