Table 1.
Head ultrasound findings by GA (Canadian Neonatal Network 2014/2016)
| Weeks GA | Number with available imaging | GM hemorrhage Number (per cent) (Grade 1 IVH) |
Intraventricular hemorrhage (IVH) (Grade 2 and 3 IVH) |
Intraparenchymal lesion (Grade 4 IVH) |
PVL |
|---|---|---|---|---|---|
| 22 | 29 | 10 (34%) | 14 (48%) | 3 (10%) | 0 |
| 23 | 218 | 128 (59%) | 114 (52%) | 45 (21%) | 17 (8%) |
| 24 | 548 | 272 (50%) | 248 (45%) | 103 (19%) | 27 (5%) |
| 25 | 719 | 303 (42%) | 233 (32%) | 87 (12%) | 40 (5.6%) |
| 26 | 844 | 295 (35%) | 224 (27%) | 68 (8%) | 35 (4%) |
| 27 | 969 | 282 (29%) | 171 (18%) | 46 (4.7%) | 23 (2.4%) |
| 28 | 1166 | 266 (23%) | 145 (12%) | 34 (2.9%) | 29 (2.5%) |
| 29 | 1286 | 278 (22%) | 150 (12%) | 30 (2.3%) | 28 (2.2%) |
| 30 | 1397 | 243 (17%) | 81 (6%) | 19 (1.4%) | 25 (1.8%) |
| 31 | 1601 | 237 (15%) | 78 (5%) | 19 (1.2%) | 20 (1.2%) |
| 32 | 1303 | 155 (12%) | 56 (4.3%) | 18 (1.4%) | 14 (1.1%) |
Data excludes moribund infants, those with major congenital anomalies, and those with no neuroimaging results. Imaging findings were not mutually exclusive (i.e., a neonate may have had more than one finding).
GA Gestational age; GM Germinal matrix; IVH Intraventricular hemorrhage; PVL Periventricular leukomalacia.