Clinical and histologic data of patients with positive and negative findings on MRI
| Negative MRI Findings | Positive MRI Findings | Total | |
|---|---|---|---|
| No. of patients | 29 | 42 | 71 |
| Sex ratio (M/F) | 0.8 | 1.8 | 1.3 |
| Age at onset (yr) (median) (range) | 6 (1–20) | 5.8 (1–20) | 6 (1–20) |
| Age at surgery (yr) (median) (range) | 17 (8–41) | 22.5 (8–52) | 20 (8–52) |
| Location of FCD | |||
| Left/right ratio | 1.4 | 1.25 | 1.35 |
| Frontal lobe | 23 | 37 | 60 |
| Parietal lobe | 4 | 3 | 7 |
| Temporal lobe | 1 | 1 | 2 |
| Occipital lobe | 1 | 1 | 2 |
| Type 2 FCD subtypes | |||
| Type 2a (no balloon cells) | 6 | 2 | 8 |
| Type 2b (balloon cells) | 23 | 40 | 63 |