Table 4.
ERG and clinical follow up
| Case | No of ERGs* | ERG changes | Clinical changes since initial ERG |
| 1 | 3 (50) | Stable | Sudden loss of colour vision in RE 6 years later. |
| 2 | 1 | – | Not available |
| 3 | 3 (63) | Stable | VA fell from 6/12 to 6/36 over 5 years. Developed transient episodes of loss of vision. Fundus remains normal |
| 4 | 9 (69) | See text | |
| 5 | 3 (22) | Mild deterioration in cone ERGs and PERG | Mild deterioration in colour contrast sensitivity over 2 years |
| 6 | 1 | – | Persistent inflammation, sudden reduction in VA LE from 6/12 to 6/36 after 1 year associated with episode of vitritis without CMO. Vitritis settled with steroids but VA unchanged 1 year later |
| 7 | 2 (10) | See text | |
| 8 | 5 (24) | Stable | Right lens opacity developed over 5 years, otherwise stable |
| 9 | 1 | – | Stable since last tested 3 years ago |
| 10 | 8 (67) | See text | |
| 11 | 2 (10) | Stable | Stable over 10 months |
| 12 | 1 | – | – |
*The period between first and last ERGs are shown as months in parentheses. VA, Snellen visual acuity.