Eyes

Additional findings may include the following:

• Hypermetric horizontal saccades (without nystagmus or disturbance of vestibuloocular reflex gain) in about half

• Mild hyperreflexia (typically without spasticity or extensor plantar responses) in a minority

• Postural tremor of arms with or without involvement of the head (seen in a minority; may be the first symptom)

Neuroimaging

Source: GeneReviews — "Spinocerebellar Ataxia Type 20"

Treatment of Manifestations

Affected persons should be followed by a neurologist with consultation from physiatrists and physical and occupational therapists. Although neither exercise nor physical therapy has been shown to stem the progression of incoordination or muscle weakness, individuals should maintain activity. Canes and walkers help prevent falls. Modification of the home with such conveniences as grab bars, raised toilet seats, and ramps to accommodate motorized chairs may be necessary. Speech therapy and communication devices such as writing pads and computer-based devices may benefit those with dysarthria or dysphonia. Weighted eating utensils and dressing hooks help maintain a sense of independence. Weight control is important because obesity can exacerbate difficulties with ambulation and mobility. When dysphagia becomes troublesome, videofluoroscopic swallow evaluation can identify the consistency of food least likely to trigger aspiration.

Prevention of Secondary Complications

Secondary complications are unlikely in the early years of the disease. Later, prevention of f...

Source: GeneReviews — "Spinocerebellar Ataxia Type 20"

Phenotype severity distribution: 6 common features.

Estimated prevalence: <1 in 1,000,000 (VERY_RARE).