STRUCTURAL AND FUNCTIONAL MAGNETIC RESONANCE (MR) GUIDED FUNCTIONAL NEUROSURGERY FOR MOVEMENT DISORDERS

Inglese

Movement disorders are a group of central nervous system conditions characterized by abnormal increased movements, which may be voluntary or involuntary. Common types of movement disorders include Parkinson’s disease, essential tremor and dystonia. Functional neurosurgery, including both neurostimulation and ablative therapies, involves precise surgical targeting of the involved anatomical structures in order to modulate neurologic function. They have become well-established therapies for movement disordersand few treatments are as effective as those for controlling the troubling motor symptoms and quality of life. The efficacy of functional neurosurgery in these clinical syndromes is determined by the severity of extrapyramidal involvement, the interactionbetween cortico-pallido-thalamic and cerebello-thalamo-cortical circuits and motor network reorganization. Evenwith established indications to surgery, key questions remain unanswered. It is not yet clear, in fact, how the clinical benefit with surgical proceduresis achieved, why some symptoms (e.g., tremor) respond more quickly than others, and why the therapeutic benefits of surgerystill vary among patients.Advances in the field of functional neurosurgery and neuroradiology are expanding our knowledge of the areas and circuits underlying the clinical expression of several neurologic movement disorders in the recent years. In this dissertation, I have applied advanced magnetic resonance imaging (MRI) techniques to patients with Parkinson’s disease in order toi)identify movement disorders-related functional and structural brain connectivity patterns with the goal of expanding our understanding of the abnormalities in motor circuit dynamics and structural abnormalities in these patients; ii)support clinical indication to surgery and to predict which patients would be eligible for functional procedures in the earlier stages of disease; iii) improve effectiveness of the neurosurgical approaches through a better identification of the brain targets and their connections;iv)understand how targeted nuclei connectivity changes after surgery. Furthermore, I have also extended advanced MRI analysis techniques in patients affected by pain disorders, like trigeminal neuralgia, due to the recent hypotheses of central nervous system involvement in the pathophysiology of disease. Our findings support a crucial role of structural and functional MRI in understanding movement and pain disorders brain networks and in providing new tools to refine targeting and patient selection, as well as to better understand the treatment mechanisms of action and disease pathophysiology.