Table 1.
Differences in the volume and volume ratio of the segmented regions according to sex
| All | Female | Male | p value | |
|---|---|---|---|---|
| Total number | 133 | 87 | 46 | |
| Age (years) | 47.7 ± 16.8 | 46.7 ± 16.2 | 49.8 ± 17.9 | 0.372 |
| 20s | 22 | 16 | 6 | |
| 30s | 25 | 15 | 10 | |
| 40s | 24 | 14 | 10 | |
| 50s | 25 | 20 | 5 | |
| 60s | 22 | 15 | 7 | |
| 70s | 13 | 7 | 6 | |
| 80s < | 2 | 0 | 2 | |
| Intracranial space (volume, mL) | 1443.3 ± 129.0 | 1393.2 ± 91.2 | 1538.2 ± 137.3 | < 0.001 |
| Total brain (mL) | 1100.3 ± 113.3 | 1067.7 ± 88.1 | 1162.1 ± 129.9 | < 0.001 |
| Cortical gray matter (mL) | 457.6 ± 50.0 | 445.6 ± 43.9 | 480.4 ± 53.4 | < 0.001 |
| Frontal cortex (mL) | 168.0 ± 19.2 | 163.8 ± 17.3 | 176.0 ± 20.3 | 0.002 |
| Parietal cortex (mL) | 115.0 ± 12.7 | 112.5 ± 11.9 | 119.8 ± 13.1 | 0.006 |
| Temporal cortex (mL) | 118.5 ± 14.1 | 115.0 ± 11.9 | 125.1 ± 15.7 | < 0.001 |
| Occipital cortex (mL) | 56.1 ± 7.3 | 54.3 ± 6.4 | 59.5 ± 7.8 | < 0.001 |
| Cerebral white matter (mL) | 417.9 ± 50.9 | 405.0 ± 38.0 | 442.3 ± 62.4 | < 0.001 |
| Cerebellum (mL) | 135.8 ± 13.8 | 132.6 ± 11.7 | 141.8 ± 15.5 | < 0.001 |
| Brainstem (mL) | 42.7 ± 3.8 | 41.4 ± 3.2 | 45.0 ± 3.7 | < 0.001 |
| Insula cortex (mL) | 12.8 ± 1.4 | 12.3 ± 1.2 | 13.7 ± 1.4 | < 0.001 |
| Hippocampus (mL) | 6.8 ± 0.7 | 6.6 ± 0.5 | 7.2 ± 0.8 | < 0.001 |
| Basal ganglia (mL) | 13.6 ± 1.5 | 13.2 ± 1.3 | 14.4 ± 1.5 | < 0.001 |
| Limbic system (mL) | 33.2 ± 3.8 | 32.2 ± 3.3 | 35.3 ± 4.0 | < 0.001 |
| Total ventricle (mL) | 25.2 ± 12.2 | 22.6 ± 10.4 | 30.1 ± 13.8 | < 0.001 |
| Lateral ventricle (mL) | 22.6 ± 11.6 | 20.2 ± 10.0 | 27.1 ± 13.0 | < 0.001 |
| Third ventricle (mL) | 1.0 ± 0.6 | 0.9 ± 0.5 | 1.3 ± 0.7 | < 0.001 |
| Fourth ventricle (mL) | 1.6 ± 0.4 | 1.5 ± 0.3 | 1.7 ± 0.4 | 0.030 |
| Total subarachnoid space (mL) | 297.7 ± 55.9 | 281.6 ± 42.3 | 328.1 ± 65.7 | < 0.001 |
| Intracranial CSF space (mL) | 322.9 ± 64.9 | 304.2 ± 49.2 | 358.2 ± 76.1 | < 0.001 |
| Total ventricle on 3D T2 (mL) | 26.9 ± 12.1 | 24.5 ± 10.6 | 31.6 ± 13.5 | < 0.001 |
| Total subarachnoid space on 3D T2 (mL) | 251.1 ± 62.0 | 232.6 ± 51.2 | 286.7 ± 66.1 | < 0.001 |
| Intracranial CSF space on 3D T2 (mL) | 278.0 ± 70.0 | 257.2 ± 57.5 | 318.3 ± 74.8 | < 0.001 |
| Total brain (volume ratio, %) | 76.2 ± 3.4 | 76.6 ± 3.0 | 75.5 ± 4.1 | 0.176 |
| Cortical gray matter (%) | 31.7 ± 2.0 | 32.0 ± 1.9 | 31.2 ± 2.0 | 0.058 |
| Frontal cortex (%) | 11.6 ± 0.8 | 11.7 ± 0.8 | 11.4 ± 0.8 | 0.073 |
| Parietal cortex (%) | 8.0 ± 0.6 | 8.1 ± 0.6 | 7.8 ± 0.5 | 0.013 |
| Temporal cortex (%) | 8.2 ± 0.6 | 8.2 ± 0.6 | 8.1 ± 0.7 | 0.350 |
| Occipital cortex (%) | 3.9 ± 0.3 | 3.9 ± 0.4 | 3.9 ± 0.3 | 0.665 |
| Cerebral white matter (%) | 28.9 ± 2.0 | 29.1 ± 1.6 | 28.7 ± 2.5 | 0.485 |
| Cerebellum (%) | 9.4 ± 0.8 | 9.5 ± 0.7 | 9.2 ± 0.8 | 0.029 |
| Brainstem (%) | 3.0 ± 0.2 | 3.0 ± 0.2 | 2.9 ± 0.2 | 0.123 |
| Insula cortex (%) | 0.89 ± 0.06 | 0.88 ± 0.06 | 0.89 ± 0.06 | 0.769 |
| Hippocampus (%) | 0.48 ± 0.03 | 0.48 ± 0.03 | 0.47 ± 0.04 | 0.271 |
| Basal ganglia (%) | 0.94 ± 0.08 | 0.95 ± 0.07 | 0.94 ± 0.09 | 0.936 |
| Limbic system (%) | 2.3 ± 0.1 | 2.3 ± 0.1 | 2.3 ± 0.1 | 0.645 |
| Total ventricle (%) | 1.7 ± 0.8 | 1.6 ± 0.7 | 1.9 ± 0.8 | 0.017 |
| Lateral ventricle (%) | 1.5 ± 0.7 | 1.4 ± 0.7 | 1.7 ± 0.8 | 0.018 |
| Third ventricle (%) | 0.07 ± 0.04 | 0.06 ± 0.03 | 0.08 ± 0.04 | 0.008 |
| Fourth ventricle (%) | 0.11 ± 0.02 | 0.11 ± 0.02 | 0.11 ± 0.03 | 0.867 |
| Intracranial CSF space (%) | 22.4 ± 3.9 | 21.9 ± 3.5 | 23.3 ± 4.6 | 0.131 |
p-values of the sex difference based on the Mann–Whitney–Wilcoxon test