Ataxia is an abnormality in the coordination of movement associated to disorders in a large number of anatomic regions. Knowledge of the anatomy of regions related to ataxia, and the use of an appropriate algorithmic approach for radiological evaluation is essential for diagnosis. The purposes of this exhibit are: 1. Describe the different types of ataxia 2. Illustrate neuroanatomy of the motor coordination ways 3. Review different causes of ataxia and their imaging appearances.

Ataxia definition The term ataxia refers to poorly coordinated movements. It is a disorder of motor coordination that affects the amplitude and direction of movements with altered gait and associated disequilibrium. Usually results from lesions of the cerebellum and/or cerebellar connections, but in addition to cerebellar ataxia there are also cases of sensory or vestibular ataxia caused by lesions of spinal proprioceptive pathways or the vestibular system, respectively. The different types of ataxia have specific clinical features (table 1), depending on the nature and location...

Classification of Disorders Causing Ataxia in Adults Cerebellar Ataxia: Cerebellar ataxia is the result of disorder affecting the cerebellum, or its afferent or efferent tracts. - Long Duration or Gradually Progressive Cerebellar Ataxia: Chronic ataxia is the largest group and includes ataxia associated with intracranial mass lesions, paraneoplastic syndromes, congenital and hereditary disorders, multiple sclerosis, idiopathic degenerative processes, nutritional deficiencies, toxins and drugs. Mass lesions: (Fig 8 - 12) The exclusion of posterior fossa masses is usually one of the first steps in chronic cerebellar...

The imaging evaluation of ataxia can be complex and confusing. Ataxia can be divided according to its clinical presentation in cerebellar, sensorial and vestibular ataxia. The most frequent form of presentation in all types of ataxia is the slowly progressive or long duration form, in which the most appropriated imaging procedure is head magnetic resonance. The acute presentation can be secondary to stroke, infection or head trauma. In suspected stroke or infection the preferred imaging procedure is again head magnetic resonance, if the treatment is...

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