Abstract 93: Do Intracerebral Hemorrhage “Non-Expanders” Actually Expand into the Ventricular Space?

Abstract

Background: The CT-angiography spot sign as a predictor of hematoma expansion (HE) is limited by its modest sensitivity and PPV. Spot sign studies restrict HE definitions to the parenchymal component of ICH and do not consistently evaluate intraventricular hemorrhage (IVH) expansion. Decompression of ICH into the ventricular space can lead to underestimation of HE and overestimation of false-positive spot signs. We hypothesized that a proportion of ICH “non-expanders” expand into the ventricular space and including IVH expansion in HE definitions will improve the predictive performance of the spot sign. Our objectives were: 1) determine the proportion of ICH “non-expanders” who have IVH expansion, 2) determine the proportion of “false-positive” spot signs that have IVH expansion, 3) compare the known predictive performance of the spot sign to its performance when using an HE definition incorporating IVH expansion, and 4) explore the predictors of IVH expansion. Methods: We analyzed patients from the multicenter PREDICT ICH spot sign study. We defined HE as ≥6mL or ≥33% ICH expansion or >2ml IVH expansion, and compared the performance of this new definition with the conventional 6mL/33% parenchymal definition using ROC analysis. We used regression analysis to determine the predictors of IVH expansion. Results: Of 315 patients with complete imaging, 215 did not meet the 6mL/33% expansion definition ("non-expanders"). Only 14/215 (6.5%) of “non-expanders” had ≥2mL IVH expansion. Of the “false positive” spot signs, 4/39 (10.3%) had >2mL ventricular expansion. The AUC for spot sign to predict significant ICH expansion was 0.65 [95% CI 0.58-0.72], which was no different then when IVH expansion was added to the HE definition: AUC 0.64 [95% CI 0.58-0.71]. Predictors for IVH expansion included IVH at baseline (aOR 2.5, p=0.013), elevated INR (aOR 2.5, p=0.011), and spot sign (aOR 5.9, p<0.001). Conclusions: IVH expansion occurs in a small minority of “non-expanders”, and only 10% of “false positive” post signs actually expended in the ventricular space. Furthermore, revising HE definitions to include IVH expansion did not alter the predictive performance of the spot sign.