Presurgical clinical characteristics of the patient group (n=23)
| Shunt status: | |
| Non-shunted | 11 (47.8%) |
| Shunted previously | 12 (52.2%) |
| No of previous shunt revisions: | |
| None | 3 (25.0%) |
| 1 revision | 3 (25.0%) |
| 2 revisions | 3 (25.0%) |
| 4 revisions | 3 (25.0%) |
| Causes of previous shunt revisions: | |
| Growth development | 12 (60.0%) |
| Infection | 1 (5.0%) |
| Malfunction | 7 (35.0%) |
| Epilepsy: | |
| Absence | 21 (91.3%) |
| Presence | 2 (8.7%) |
| Present clinical symptoms: | |
| Asymptomatic | 7 (25.0%) |
| Minor symptoms | 16 (57.1%) |
| Hydrocephalus category: | |
| Active hydrocephalus | 5 (21.7%) |
| Compensated hydrocephalus | 18 (78.3%) |
| Level of lesion: | |
| Thoracic | 2 (8.7%) |
| Lumbar (L1–3) | 6 (26.1%) |
| Lumbar (L4–5) | 10 (43.4%) |
| Sacral | 5 (21.7%) |
| TC or MR abnormalities: | |
| Partial callosal agenesis | 5 (21.7%) |
| Thinning of corpus callosum | 9 (39.1%) |
| Heterotopias | 3 (13.0%) |
| Aqueductal stenosis | 16 (69.6%) |
| Interdigitation | 10 (43.5%) |
| Impingement | 12 (55.2%) |
| Syringomielia | 5 (21.7%) |
| Chiari I malformation | 1 (4.3%) |
| Chiari II malformation | 22 (95.7%) |
| ICP waves: | |
| Presence of A waves | 2 (8.7%)2-150 |
| Presence of B waves | 23 (100.0%) |
| Percentage of B waves during the total monitoring time: | |
| < 25% | 8 (34.8%) |
| 25–49% | 8 (34.8%) |
| 50–74% | 4 (17.4%) |
| ⩾75% | 2 (8.7%) |
| ICP mean (active group) | 16.00 (SD 3.16) |
| ICP mean (compensated group) | 9.47 (SD 2.96) |
| Evans index | 0.39 (SD 0.08) |
| Ventricular score | 108.10 (SD 24.9) |
| Cella media index | 0.34 (SD 0.08) |
| Third ventricle index | 0.10 (SD 0.05) |
↵2-150 One patient presented nocturnal A waves between 20 and 40 mm Hg. The other patient presented both diurnal and nocturnal A waves between 20 and 40 mm Hg.