Table 2.
Cox proportional hazard model for predictors of bAVM hemorrhage after SRS.
| Characteristic | Univariate | Multivariate | ||||
|---|---|---|---|---|---|---|
| HR | 95% CI | P value | HR | 95% CI | P value | |
| Compact bAVM* (vs. diffuse) | 0.47 | 0.13–1.70 | 0.248 | 0.25 | 0.06–0.99 | 0.048† |
| Age | 0.98 | 0.93–1.02 | 0.325 | – | – | – |
| Sex | 0.76 | 0.26–2.16 | 0.602 | 0.32 | 0.10–1.07 | 0.065 |
| bAVM volume | 1.04 | 1.01–1.07 | 0.011† | 1.15 | 1.04–1.27 | 0.009† |
| Aneurysm (proximal/intranidal) | 1.54 | 0.34–6.90 | 0.573 | – | – | – |
| Eloquence | 2.43 | 0.54–10.97 | 0.243 | 2.95 | 0.58–14.97 | 0.193 |
| Deep location‡ | NA | NA | NA | – | – | – |
| Deep venous drainage | 2.71 | 0.91–8.08 | 0.074 | – | – | – |
| Margin dose | 0.42 | 0.24–0.74 | 0.003† | 0.23 | 0.06–0.86 | 0.029† |
| Isodose level | 1.02 | 0.81–1.28 | 0.852 | – | – | – |
| Target coverage§ | 0.06 | 0.00–0.96 | 0.046† | 0.01 | 0.00–0.35 | 0.011† |
| bAVM volume* margin dose | NA | NA | NA | 1.11 | 1.03–1.20 | 0.008† |
*Compact bAVM is defined as compactness index ≥ 0.63.
†P < 0.05.
‡No hemorrhage event occurred in deep seated AVM (thalamus, basal ganglia, brainstem).
§Target coverage is defined as the percentage of margin dose covered volume within target volume divided by the entire target volume.