Table 1.
Eye movement abnormalities in spinocerebellar ataxias.
| Type of SCA | SWJs | Gaze evoked nystagmus | Downbeat nystagmus | Hypometric saccades | Supranuclear gaze palsy | Decreased saccade velocity | Hypermetric saccades | Impaired smooth pursuit | Hypoactive VOR |
|---|---|---|---|---|---|---|---|---|---|
| SCA 1 | − | + | − | − | − | ++ | + | − | + |
| SCA 2 | − | − | − | − | − | +++ | − | − | − |
| SCA 3 | + | ++ | − | ++ | ++ | + | − | ++ | ++ |
| SCA 6 | − | +++ | +++ | + | − | − | ++ | +++ | − |
| SCA 7 | − | − | − | − | ++ | +++ | − | − | − |
| SCA17 | − | − | − | ++ | ++ | − | − | ++ | − |
| FA | +++ | − | − | − | − | − | + | ++ | +++ |
Abbreviation: FA: Friedrich's ataxia; SCA: spinocerebellar ataxia; SWJs: Square wave jerks; VOR: vestibule-ocular reflex.