Table 1.
SWiTCH brain MRI and MRA findings by hemisphere and study time point
| Baseline (N = 150) | Exit (N = 112) | |||||
|---|---|---|---|---|---|---|
| Left | Right | Bilateral | Left | Right | Bilateral | |
| MRI | ||||||
| Location of lesion | ||||||
| Any abnormality | 132 (88%) | 122 (81%) | 106 (71%) | 101 (90%) | 92 (82%) | 82 (73%) |
| Subcortical infarct | 127 (85%) | 118 (79%) | 102 (68%) | 96 (86%) | 88 (79%) | 78 (70%) |
| Cortical infarct* | 80 (53%) | 56 (37%) | 34 (23%) | 59 (53%) | 44 (39%) | 27 (24%) |
| Subcortical and cortical* | 75 (50%) | 52 (35%) | 30 (20%) | 54 (48%) | 40 (36%) | 23 (21%) |
| MRA | ||||||
| Number of stenoses | ||||||
| 0 | 63 (42%) | 81 (54%) | 50 (45%) | 62 (55%) | ||
| 1-2 | 13 (9%) | 13 (9%) | 8 (7%) | 9 (8%) | ||
| 3-4 | 33 (22%) | 20 (13%) | 23 (21%) | 13 (12%) | ||
| ≥5 | 41 (27%) | 36 (24%) | 31 (28%) | 28 (25%) | ||
| Mean number of stenoses per subject | 2.8 | 2.3 | 2.8 | 2.3 | ||
| Subjects with stenosis | 87 (58%) | 69 (46%) | 52 (35%) | 62 (55%) | 50 (45%) | 40 (36%) |
| Maximum stenosis length (mm) | ||||||
| 6-15 | 16 (11%) | 11 (7%) | 11 (10%) | 11 (10%) | ||
| 16-25 | 34 (23%) | 28 (19%) | 24 (21%) | 18 (16%) | ||
| ≥26 | 37 (25%) | 28 (19%) | 27 (24%) | 21 (19%) | ||
| Occlusion grade | ||||||
| Grade 0 | 63 (42%) | 81 (54%) | 50 (45%) | 62 (55%) | ||
| Grade 1-3 | 8 (5%) | 8 (5%) | 8 (7%) | 7 (6%) | ||
| Grade 4-6 | 79 (53%) | 61 (41%) | 54 (48%) | 43 (38%) | ||
Each cerebral hemisphere and its corresponding vessels were reported separately because they represent functionally and structurally independent systems.
*
P < .05 using a McNemar’s test to compare distribution between hemispheres.