Table 1.
Participant characteristics
| Healthy controls | Patients with optic neuritis | |
|---|---|---|
| n | 37 | 71 |
| Mean age, years ± SD (range) | 34.4 ± 4.8 (27–47) | 33.5 ± 6.7 (20–48) |
| female : male | 25 : 12 | 49 : 22 |
| Median baseline EDSS (range) | - | 1 (0–3) |
| Number with abnormal T2 scan (excluding symptomatic lesion) | - | 55 |
| Number with periventricular lesions | - | 46 |
| Number with Gd-enhancing lesions | - | 22 |
| Mean T2 lesion volume (ml) ± SD | - | 1.47 ± 3.32 |
| Mean brain parenchymal fraction ± SD | 0.84 ± 0.04 | 0.85 ± 0.03 |
| Number attaining CDMS at time of MTR scan | - | 8 |
| Number attaining McDonald multiple sclerosis at time of MTR scan | - | 33 |
| Number with clinical follow-up at 2 and 5 years | - | 58 |
| Number converting to CDMS within 2 years of optic neuritis (of 58 with clinical follow-up) | - | 18 |
| Number converting to McDonald multiple sclerosis within 2 years of optic neuritis (of 58 with clinical follow-up) | - | 40 |
| Number converting to CDMS within 5 years of optic neuritis (of 58 with clinical follow-up) | - | 31 |
| Number converting to McDonald multiple sclerosis within 5 years of optic neuritis (of 58 with clinical follow-up) | - | 45 |
| Median (range) EDSS score at 5-year follow-up (assessed in 50/58) | - | 1 (0-8.5) |
| Median (range) PASAT score at 5-year follow-up (assessed in 31/58) | - | 46.5 (17-59) |
In the optic neuritis group, MTR scans were undertaken 3 months after first enrolment in the study, and so lesion measures from scans obtained at 3 months are shown. Volumetric brain scans were acquired at baseline but not at 3 months. PASAT = Paced Serial Addition Test, 3-s intervals.