Resting-state functional magnetic resonance imaging of the subthalamic microlesion and stimulation effects in Parkinson's disease: Indications of a principal role of the brainstem.

Abstract:

During implantation of deep-brain stimulation (DBS) electrodes in the target structure, neurosurgeons and neurologists commonly observe a "microlesion effect" (MLE), which occurs well before initiating subthalamic DBS. This phenomenon typically leads to a transitory improvement of motor symptoms of patients suffering from Parkinson's disease (PD). Mechanisms behind MLE remain poorly understood. In this work, we exploited the notion of ranking to assess spontaneous brain activity in PD patients examined by resting-state functional magnetic resonance imaging in response to penetration of DBS electrodes in the subthalamic nucleus. In particular, we employed a hypothesis-free method, eigenvector centrality (EC), to reveal motor-communication-hubs of the highest rank and their reorganization following the surgery; providing a unique opportunity to evaluate the direct impact of disrupting the PD motor circuitry in vivo without prior assumptions. Penetration of electrodes was associated with increased EC of functional connectivity in the brainstem. Changes in connectivity were quantitatively related to motor improvement, which further emphasizes the clinical importance of the functional integrity of the brainstem. Surprisingly, MLE and DBS were associated with anatomically different EC maps despite their similar clinical benefit on motor functions. The DBS solely caused an increase in connectivity of the left premotor region suggesting separate pathophysiological mechanisms of both interventions. While the DBS acts at the cortical level suggesting compensatory activation of less affected motor regions, the MLE affects more fundamental circuitry as the dysfunctional brainstem predominates in the beginning of PD. These findings invigorate the overlooked brainstem perspective in the understanding of PD and support the current trend towards its early diagnosis.

LHA-ID: 7Q6RC653X4-0

PubMed ID: 26509113

Projects: LIFE Adult

Journal: Neuroimage Clin

Human Diseases: Parkinson's disease

Citation: Neuroimage Clin. 2015 Aug 21;9:264-74. doi: 10.1016/j.nicl.2015.08.008. eCollection 2015.

Date Published: 29th Oct 2015

Authors: S. Holiga, K. Mueller, H. E. Moller, D. Urgosik, E. Ruzicka, M. L. Schroeter, R. Jech

Help
help Creator
Activity

Views: 346

Created: 9th May 2019 at 09:38

Last updated: 9th May 2019 at 09:42

help Attributions

None

Related items

Powered by
(v.1.9.1)
Copyright © 2008 - 2019 The University of Manchester and HITS gGmbH
Institute for Medical Informatics, Statistics and Epidemiology, University of Leipzig