TABLE 1.
Clinical characteristics of study population
| Characteristic | Lateral hemispherotomy, n = 600 | Vertical hemispherotomy, n = 72 | p |
|---|---|---|---|
| Centers, n | 21 | 4 | |
| HOPS score | 2.27 ± 1.05 | 2.35 ± 1.02 | .589 |
| Age at seizure onset, years | 1.89 ± 2.70 | 2.34 ± 2.87 | .171 |
| Age at seizure onset | |||
| <3 months | 187 (31.2%) | 16 (23.5%) | .345 |
| 3 months–3.5 years | 288 (48.0%) | 34 (50.0%) | |
| >3.5 years | 125 (20.8%) | 18 (26.5%) | |
| Generalized seizure semiology | |||
| Yes | 192 (32.1%) | 41 (59.4%) | <.001* |
| No | 407 (67.9%) | 28 (40.6%) | |
| Previous surgery | |||
| Yes | 92 (15.3%) | 8 (11.1%) | .438 |
| No | 508 (84.7%) | 64 (88.9%) | |
| Stroke etiology | |||
| Yes | 224 (37.5%) | 32 (44.4%) | .306 |
| No | 374 (62.5%) | 40 (55.6%) | |
| Epilepsy etiology | |||
| Porencephalic cyst/stroke | 224 (37.5%) | 32 (44.4%) | .220 |
| Malformations of cortical development | 114 (19.1%) | 14 (19.4%) | |
| Hemimegalencephaly | 92 (15.4%) | 4 (5.6%) | |
| Rasmussen's encephalitis | 67 (11.2%) | 6 (8.3%) | |
| Sturge–Weber syndrome | 26 (4.3%) | 5 (6.9%) | |
| Hemiconvulsion–hemiplegia syndrome | 7 (1.2%) | 0 (.0%) | |
| Other | 68 (11.4%) | 11 (15.3%) | |
| FDG‐PET scan | |||
| Bilateral hypometabolism | 16 (2.7%) | 9 (14.8%) | <.001* |
| Contralateral hypometabolism | 5 (.8%) | 0 (.0%) | |
| Ipsilateral hypometabolism | 244 (40.9%) | 50 (82.0%) | |
| Not scanned | 331 (55.5%) | 2 (3.3%) | |
| MRI scan | |||
| Contralateral lesion | 84 (14.2%) | 7 (12.7%) | .916 |
| Bilateral interictal EEG | |||
| Yes | 75 (18.0%) | 7 (63.6%) | <.001* |
| No | 342 (82.0%) | 4 (36.4%) | |
| Infantile spasms | |||
| Yes | 123 (28.5%) | 20 (36.4%) | .292 |
| No | 309 (71.5%) | 35 (63.6%) | |
| Number of seizure semiologies | |||
| One | 313 (52.2%) | 14 (25.5%) | <.001* |
| Two or more | 284 (47.4%) | 41 (74.5%) | |
| Seizure recurrence | |||
| Yes | 126 (21.0%) | 10 (13.9%) | .206 |
| No | 474 (79.0%) | 62 (86.1%) | |
Values are presented as number of patients (%) or mean ± SD (range).
Abbreviations: EEG, electroencephalogram; FDG‐PET, 18‐fluoro‐2‐deoxyglucose‐positron emission tomography; HOPS, Hemispheric Surgery Outcome Prediction Scale; MRI, magnetic resonance imaging.
*p < .05.