Quantitative and qualitative evaluation of collateral flow using time-resolved C-arm CBCTA data
| Case | Acute Occlusion Site | Flow Direction of MCAa | Measuring Point | Difference of Time-to-Peak (Lesion-Normal)b | Relative Peak Density (Lesion/Normal)c | Score of Tan et al13 (0–3) | Score of Miteff et a114 (3-Point) | Score of Maas et al4 (1–5) |
|---|---|---|---|---|---|---|---|---|
| 1 | R-M1 | R | Proximal M2 | 10 sec (29–9) | 84.8% (302/356) | 3 | Good | 4 |
| 2 | L-M1 | R | Proximal M2 | 9 sec (31–13) | 60.1% (292/486) | 2 | Good | 2 |
| 3 | L-M1 | A | Proximal M2 | 1.5 sec (10–7) | 90.8% (364/401) | 3 | Good | 3 |
| 4 | R-ICA T | R | Proximal M1 | 8.5 sec (34–17) | 58.6% (396/676) | 3 | Good | 3 |
| 5 | L-ICA and M1 | R | Proximal M2 | 8 sec (52–36) | 58.0% (341/588) | 1 | Good | 2 |
| 6 | L-ICA | A | Distal M1 | 4 sec (64–56) | 62.8% (301/479) | 3 | Good | 3 |
| 7 | L-ICA | A | Distal M1 | 2.5 sec (20–15) | 80.3% (309/385) | 3 | Good | 3 |
| 8 | R-M2 | NA | NA | NA | NA | NA | NA | NA |
| 9 | R-M2 | NA | NA | NA | NA | NA | NA | NA |
| 10 | BA and L-P1 | NA | NA | NA | NA | NA | NA | NA |
Note:—R indicates right; L, left; NA, not applicable; BA, basilar artery; T, terminus.
↵a A indicates antegrade; R, retrograde.
↵b Data in parentheses are the frame differences for time-to-peak. Each frame represents 0.5 seconds.
↵c Data in parentheses are the Hounsfield units of measured points, which represent the level of enhancement of the vessel.