Radiodensity of intraventricular hemorrhage associated with aneurysmal subarachnoid hemorrhage may be a negative predictor of outcome

OBJECTIVE The presence, extent, and distribution of intraventricular hemorrhage (IVH) have been associated with negative outcomes in aneurysmal subarachnoid hemorrhage (SAH). Several qualitative scores (Fisher grade, LeRoux score, and Graeb score) have been established for evaluating SAH and IVH. However, no study has assessed the radiodensity within the ventricular system in aneurysmal SAH patients with IVH. Prior studies have suggested that hemorrhage with a higher radiodensity, as measured by CT Hounsfield units, can cause more irritation to brain parenchyma. Therefore, the authors set out to investigate the relationship between the overall radiodensity of the ventricular system in aneurysmal SAH patients with IVH and their clinical outcome scores. METHODS The authors reviewed the records of 101 patients who were admitted to their institution with aneurysmal SAH and IVH between January 2011 and July 2015. The following data were collected: age, sex, Glasgow Coma Scale (GCS) score, Hunt and Hess grade, extent of SAH (none, thin, or thick/localized), aneurysm location, and Glasgow Outcome Scale (GOS) score. To evaluate the ventricular radiodensity, the initial head CT scan was loaded into OsiriX MD. The ventricular system was manually selected as the region of interest (ROI) through all pertinent axial slices. After this, an averaged ventricular radiodensity was calculated from the ROI by the software. GOS scores were dichotomized as 1-3 and 4-5 subgroups for analysis. RESULTS On univariate analysis, younger age, higher GCS score, lower Hunt and Hess grade, and lower ventricular radiodensity significantly correlated with better GOS scores (all p < 0.05). Subsequent multivariate analysis yielded age (OR 0.936, 95% CI 0.895-0.979), GCS score (OR 3.422, 95% CI 1.9-6.164), and ventricular density (OR 0.937, 95% CI 0.878-0.999) as significant independent predictors (p < 0.05). A receiver operating characteristic curve yielded 12.7 HU (area under the curve 0.625, p = 0.032, sensitivity = 0.591, specificity = 0.596) as threshold between GOS scores of 1-3 and 4-5. CONCLUSIONS This study suggests that the ventricular radiodensity in aneurysmal SAH patients with IVH, along with GCS score and age, may serve as a predictor of clinical outcome.