Table 1:
Summary of data describing the number and incidence of thromboembolic and perforation events during unassisted and balloon-assisted coiling of cerebral aneurysms
| Variable | % Incidence ± SD | No. of Events | No. of Aneurysms | No. of Articles | Odds Ratio | Confidence Interval |
|---|---|---|---|---|---|---|
| Thromboembolic incidence, all articles, balloon | 8.1 ± 5.7 | 22 | 273 | 11 | NA | NA |
| Thromboembolic incidence, all articles, no balloon | 8.0 ± 5.7 | 69 | 867 | 17 | ||
| Thromboembolic incidence, “mixed articles,” balloon | 7.9 ± 6.1 | 7 | 89 | 5 | 0.7 | 0.3-1.7 |
| Thromboembolic incidence, “mixed articles,” no balloon | 10.5 ± 8.4 | 36 | 344 | 5 | ||
| Perforation incidence, balloon SAH cases | 1.7 ± 9.4 | 1 | 59 | 7 | NA | NA |
| Perforation incidence, nonballoon SAH cases | 3.4 ± 6.3 | 17 | 507 | 13 | ||
| Perforation incidence, balloon non-SAH cases | 1.8 ± 2.1 | 2 | 111 | 8 | NA | NA |
| Perforation incidence, non-balloon non-SAH cases | 1.4 ± -2.3 | 7 | 486 | 12 |
Note:—“Mixed articles” indicates studies reporting results for both balloon-assisted and unassisted coiling cases and were the ones subject to meta-analysis. The incidence of thromboembolism for the larger cohort of “all articles,” which includes a wider range of studies reporting exclusive experience with either unassisted or balloon-assisted cases, does not lend itself to strict meta-analysis, however, is included in the chart for comparison with the analyzed results for the “mixed article” groups. SAH indicates subarachnoid hemorrhage; NA, no analysis.