ABSTRACT
I. Introduction 133
II. Anatomic Pathology (CT and MRI) 134
III. Functional Imaging 134
A. Resting State 134
B. Physiologic Activation 135
IV. Neuroimaging of Therapeutic Interventions 136
A. Effects of Drugs 136
B. Effects of Neurosurgical Lesions 137
C. Effects of Deep Brain Stimulation 137
V. Future Directions 140
Acknowledgments 141
References 141
I. INTRODUCTION
Essential tremor is one of the most common neurologic movement disorders with
a prevalence between 0.3% and 4% in the United States (1) and may affect the
limbs, head, neck, voice, or various combinations. About half of the patients
have an autosomal dominant pattern of inheritance (2,3) but only two different
gene loci have been linked to essential tremor in different pedigrees (4,5).
The underlying pathophysiology remains elusive with no clear findings on patho-
logic examinations of brains (6,7). Neuroimaging, however, has provided several
clues to the pathophysiology of essential tremor and mechanisms of action of
therapeutic interventions.
