Troubles neurologiques

Advanced Radiological Investigation of Levodopa-Induced Dyskinesia in Parkinson’s Disease Patients: Assessment of Blood Brain Barrier Function

Abstract

Ophir Segal, David Guez, David Last, Yael Mardor, Gilad Yahalom, Lior Orbach, Oren S Cohen, Sandra Benizri, Simon Israeli-Korn, Chen Hoffman and Sharon Hassin-Baer

Background: To explore changes in blood-brain barrier (BBB) function and volumetry associated with Parkinson’s disease (PD) levodopa-induced-dyskinesia (LID). Methods: 26 PD patients [13 with LID (LID+) and 13 without (LID-)], matched into pairs, performed high resolution 3D FSPGR MRI, applying a methodology based on delayed contrast extravasation developed for calculating delayedenhancement subtraction-maps, exploring contrast clearance or accumulation, representing BBB function. Segmentation software calculated volumes of pre-determined brain structures and the mean signal intensity was calculated, reflecting each structure’s BBB function. Comparisons between the LID+ and LID- paired patients and within patient, between the more and less affected hemisphere (MAH, LAH) and correlation tests with lateralized UPDRS motor scores were performed. Results: There were no significant differences in volumetric or BBB map characteristics between the matched LID+ and LID- patients regarding most brain areas except for the inferior parietal cortex (IPC) of the MAH that displayed a less negative signal suggesting slightly higher BBB disruption in LID+ vs. LID- patients. A positive correlation was found with the motor score of the side contralateral to the MAH (r = 0.58, p<0.038) among the LID+ patients. Within-patient comparison of the MAH and LAH failed to reveal asymmetry in BBB function or volume in any of the brain areas studied. Conclusion: We demonstrated an association between slight BBB disruption in the IPC and LID in patients with PD using a new MRI methodology. Further studies to explore BBB functioning in the various stages of PD and its motor complications are needed.