Midbrain ataxia: an introduction to the mesencephalic locomotor region and the pedunculopontine nucleus.

Department of Radiology, Geffen School of Medicine, University of California-Los Angeles Medical Center, Los Angeles, CA 90095, USA.
American Journal of Roentgenology (Impact Factor: 2.9). 04/2005; 184(3):953-6.
Source: PubMed

ABSTRACT OBJECTIVE: Although gait ataxia is usually associated with cerebellar lesions, we review a less familiar cause. We present three patients with dorsal midbrain lesions and correlate these presentations with recent findings in the functional anatomy of the midbrain. CONCLUSION: We suggest that these lesions involve a well-studied but generally unfamiliar area of the dorsal midbrain known as the mesencephalic locomotor region. More specifically, we hypothesize that involvement of the pedunculopontine nucleus, a major component of the mesencephalic locomotor region, may be at least partially responsible for producing midbrain ataxia.

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