Patient | Nystagmus characteristics | Neuroimaging | ERG | VEP | Horizontal OKN | Diagnosis | ||||||
1 | Circumrotatory in primary, vertical in lateral gaze | no | poor cone mediated ERGs | att pattern VEPs to all check sizes | present | cone dysfunction | ||||||
2 | Upbeat in primary and upgaze, horizontal in lateral gaze | MRI: N | poor cone mediated ERGs | att pattern VEPs to all check sizes | absent | cone dysfunction | ||||||
3 | Fine vertical pendular | MRI: N | poor cone mediated ERGs | att pattern VEPs to all check sizes | present | cone dysfunction | ||||||
4 | Fine vertical pendular | no | poor cone mediated ERGs | att pattern VEPs to all check sizes | not tested | cone dysfunction | ||||||
5 | Asymmetric fine horizontal pendular mainly in LE | MRI and CT: N | poor cone mediated ERGs | pattern VEPs to medium and large checks (50′–400′) | present | cone dysfunction | ||||||
6 | Fine vertical pendular | no | poor cone mediated ERGs | pattern VEPs to medium and large checks (50′–400′) | not tested | cone dysfunction | ||||||
7 | Fine vertical pendular and circumrotatory, head shake | CT: N | poor cone mediated ERGs | pattern VEPs to medium and large checks (50′–400′) | present | cone dysfunction | ||||||
8 | Fine vertical pendular | no | poor cone mediated ERGs | att pattern VEPs to all check sizes | not tested | cone dysfunction | ||||||
9 | Vertical pendular, worse in LE, horizontal in lateral gaze | MRI and CT: N | poor cone and rod mediated ERGs | pattern VEPs to large checks only (200–400′) | present | cone-rod dystrophy | ||||||
10 | Asymmetric (LE worse) fine horizontal pendular in primary and L gaze, jerk in R gaze | MRI: N | poor cone and rod mediated ERGs | att pattern VEPs to all check sizes | present | cone-rod dystrophy | ||||||
11 | Asymmetric fine horizontal pendular mainly in LE | MRI: N | normal | att pattern VEPs to all check sizes | present | albinism | ||||||
Crossed asymmetry flash VEP | ||||||||||||
12 | Vertical upbeat some horizontal pendular | MRI: N | well preserved a wave, poor b wave (negative ERG) | att and delayed pattern VEPs to all check sizes | absent | X linked CSNB | ||||||
13 | Vertical upbeat and pendular, horizontal jerk on lateral gaze | MRI: N | normal | pattern VEPs smaller than average to all check sizes | present | CIN | ||||||
14 | Downbeat worse in upgaze | MRI: N | normal | pattern VEPs smaller than average to all check sizes | present | CIN |
VEP “attenuated VEPs” refer to clinically significant degradation of the responses, “VEPs smaller than average” implies small responses that are just within the normal amplitude range. (N=normal; att=attenuated, CSNB=congenital stationary nightblindness; CIN congenital idiopathic nystagmus; poor=significantly attenuated or absent.)