Immediate and follow-up results of the treated aneurysms according to the BOSS classification12
| BOSS Classification | RROC Grades | Immediate (n) | Ratio BOSS (%) | Ratio RROC (%) | FU1 (n) | Ratio BOSS (%) | Ratio RROC (%) | FU2 (n) | Ratio BOSS (%) | Ratio RROC (%) |
|---|---|---|---|---|---|---|---|---|---|---|
| 47 | 36 | 18 | ||||||||
| 0 | I | 14 | 29.8 | 31.9 | 20 | 55.6 | 63.9 | 13 | 72.2 | 77.8 |
| 0′ | 1 | 2.1 | 3 | 8.3 | 1 | 5.6 | ||||
| 1 | II | 28 | 59.6 | 59.6 | 4 | 11.1 | 36.1 | 1 | 5.6 | 22.2 |
| 2 | 0 | 0.0 | 9 | 25.0 | 3 | 16.6 | ||||
| 3 | III | 1 | 2.1 | 8.5 | 0 | 0.0 | 0.0 | 0 | 0.0 | 0.0 |
| 1 + 3 | 3 | 6.4 | 0 | 0 | 0 | 0.0 |
Note:—FU1 indicates first follow-up angiography; FU2, second follow-up angiography.
BOSS classification12: 0, No residual flow inside the aneurysm or the WEB; 0′, opacification of the proximal recess of the WEB; 1, residual flow inside the WEB; 2, neck remnant; 3, aneurysm remnant; 1 + 3, contrast media depicted inside and around the device. BOSS results were transferred into the RROC.13 RROC classification: RROC I, complete occlusion (BOSS 0 and 0′); RROC II, neck remnant (BOSS 1 and 2); RROC III, aneurysm remnant (BOSS 3 and 1 + 3).