Table 1.
Findings in patients with paroxysmal downbeat central positional nystagmus.
| Pt | Etiology | Sex/Age | SN fix | SN non-fix | GEN | HSN | Manual | Rotatory chair | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Max SPV | TC | Max SPV | TC | |||||||||||||||
| Slow | Fast | Slow | Fast | 10° /s | 20° /s | 30° /s | 40° /s | 10° /s | 20° /s | 30° /s | 40° /s | |||||||
| 1 | SCA 6 | M/56 | - | D | - | R+D | 0.0 | 14.5 | - | 3.4 | 8.7 | 14.6 | 14.7 | 16.5 | 7.1 | 7.8 | 6.3 | 4.5 |
| 2 | ACM | F/66 | D | R+D | +(REB) | R → L+D | 0.0 | 30.0 | - | 4.3 | 6.7 | 11.2 | 15.8 | 21.9 | 7.7 | 4.1 | 4.3 | 4.3 |
| 3 | SCA | F/45 | D | R+D | +(REB) | R+D | 0.0 | 16.0 | - | 7.4 | 11.4 | 16.4 | 20.3 | 18.2 | 2.9 | 4.0 | 3.8 | 4.1 |
| 4 | CA | F/70 | - | L | +(REB) | - | 10.4 | 25.7 | 1.3 | 1.4 | 8.0 | 16.5 | 22.1 | 23.3 | 2.3 | 2.8 | 1.5 | 1.1 |
| 5 | CA | F/72 | - | - | +(REB) | R → L | 12.3 | 23.1 | 3.7 | 6.2 | 9.2 | 12.1 | 12.1 | 13.5 | 3.0 | 4.9 | 4.3 | 5.7 |
| 6 | SCA 1 | M/62 | - | D | - | R → L+D | 0.0 | 16.2 | - | 2.0 | 6.4 | 11.3 | 14.2 | 18.5 | 2.9 | 1.9 | 1.5 | 1.5 |
| 7 | EA2 | F/22 | D | R+D | - | L → R+D | 0.0 | 19.8 | - | 2.0 | 0.0 | 6.5 | 17.4 | 24.1 | - | 3.0 | 2.6 | 2.4 |
| 8 | CA | M/48 | - | - | + | D | 0.0 | 11.6 | - | 5.3 | 15.7 | 23.8 | 22.8 | 16.3 | 4.0 | 3.2 | 4.6 | 5.9 |
| 9 | CA | F/43 | - | D | - | R+D | 0.0 | 19.5 | - | 4.5 | 8.5 | 14.0 | 16.5 | 19.5 | 2.6 | 4.0 | 4.2 | 3.7 |
| 10 | CA | M/72 | - | L+D | - | L+D | 0.0 | 26.7 | - | 3.5 | 5.5 | 8.0 | 8.4 | 6.7 | 3.1 | 3.1 | 3.2 | 3.8 |
| 11 | CA | M/47 | - | U+OF | + | - | 0.0 | 35.9 | - | 2.7 | 16.8 | 17.0 | 19.4 | 22.4 | 1.0 | 2.8 | 2.7 | 2.7 |
| 12 | CVUE | M/67 | D | D | + | D | 0.0 | 19.4 | - | 3.7 | 0.0 | 13.9 | 16.3 | 19.1 | - | 1.4 | 3.4 | 2.3 |
| 13 | EA2 | M/16 | D | D | +(REB) | L+D | 0.0 | 26.1 | - | 3.5 | 7.6 | 8.3 | 10.4 | 13.8 | 3.6 | 3.3 | 5.7 | 2.0 |
| 14 | EA | M/48 | - | D | - | D | 0.0 | 4.6 | - | 6.8 | 0.0 | 0.0 | 3.8 | 4.1 | - | - | 6.5 | 6.8 |
| 15 | CA | F/55 | - | - | +(REB) | - | 0.0 | 23.6 | - | 1.1 | 0.0 | 23.2 | 27.4 | 35.1 | - | 0.8 | 1.4 | 1.3 |
| 16 | SCA | M/66 | D | D | + | R → L+D | 0.0 | 22.2 | - | 4.7 | 10.8 | 24.7 | 25.6 | 28.8 | 2.8 | 3.6 | 4.4 | 4.2 |
| 17 | SCA | F/48 | - | - | +(REB) | D | 0.0 | 17.5 | - | 2.7 | 13.8 | 21.2 | 26.0 | 30.2 | 2.3 | 2.4 | 2.1 | 1.9 |
| 18 | OPCA | F/56 | - | - | - | D | 0.0 | 9.3 | - | 6.5 | 6.5 | 9.5 | 9.7 | 9.8 | 3.7 | 4.2 | 4.1 | 4.4 |
| 19 | EA | M/63 | - | - | + | R+D | 0.0 | 6.8 | - | 3.3 | 0 | 0 | 0 | 0 | - | - | - | - |
| 20 | CVUE | M/55 | D | D | + | R | 0.0 | 56.7 | - | 1.8 | 0 | 20.9 | 21.7 | 34.1 | - | 1.8 | 1.8 | 1.9 |
| 21 | SCA | M/65 | D+SWJ | D+SO | +(REB) | L → R+D | 0.0 | 65.6 | - | 2.7 | 16.9 | 32.5 | 44.6 | 55.2 | 1.4 | 2.7 | 2.9 | 2.7 |
ACM, Arnold-Chiari malformation; APAN, aperiodic alternating nystagmus; CA, cerebellar ataxia; CVUE, central vertigo with unknown etiology; D, downbeat nystagmus; EA, episodic ataxia; F, female; GEN, gaze-evoked nystagmus; HSN, head shaking nystagmus; L, left beating nystagmus; M, male; Max, maximum; MSO, macro saccadic oscillation; OF, ocular flutter; OPCA, olivopontocerebellar atrophy; Pt, patient; R, right beating nystagmus; REB, rebound; SCA, spinocerebellar ataxia; SPV, slow phase velocity; SN, spontaneous nystagmus; SN fix, spontaneous nystagmus with visual fixation; SN non-fix, spontaneous nystagmus without visual fixation; SO, saccadic oscillation; SWJ, square wave jerk; TC, time constant; +, present or plus; −, normal or absent; →, change to.