Background: Recently early phase clinical trials have targeted individual anatomical locations. However, information regarding ICH characteristics and outcomes of specific deep locations of ICH is limited.
Methods: ERICH is a multi-center, prospective, case-control study of a racially mixed population with ICH. ICH locations were systematically designated by a central imaging core. Subjects with supratentorial deep ICH based on initial head CT originating in the caudate, thalamus, or putamen were included. Those with pre-morbid modified Rankin Scale (mRS) > 2, positive drug screen, or missing 3-month mRS were excluded. Differences in baseline characteristics and medical interventions were examined by anatomic location, stratified by intraventricular hemorrhage (IVH) presence. Receiver operating curve analysis was performed to determine ICH volume specificity for poor outcome (mRS 4-6).
Results: A total of 945 subjects met inclusion criteria for the analysis: caudate (n=62), putamen (n=394), thalamus (n=489). Significant differences were noted for presence of IVH (caudate 89%, putamen 23%, thalamus 64%, p<.0001), ventriculostomy (caudate 52%, putamen 14%, thalamus 27%; p<.0001), and surgery (caudate 2%, putamen 10%, thalamus 2%, p<.0001). In multivariable analysis, subjects with thalamic ICH without IVH (compared with putaminal ICH without IVH) were more likely to be younger (OR 1.02; 95%CI 1.00-1.04, p=.0130, have history of hypertension (OR 2.82, 95%CI 1.24-6.39), and lower ICH volume (OR 0.28, 95%CI 0.21-0.38, p<.0001). Subjects with thalamic ICH and IVH (compared with putaminal ICH and IVH) were less likely to have surgery for evacuation (OR 0.14, 95%CI 0.04-0.46, p=.0012) and have lower ICH volume (OR 0.13, 95%CI 0.08-0.22, p<.0001). Receiver operating curve analysis identified 5.39 mL volume in thalamic ICH without IVH and 18.68 ml in putaminal ICH without IVH as having 95% specificity for poor outcome.
Conclusion: In patients with deep supratentorial ICH, IVH is significantly more common in caudate and thalamic ICH compared with putaminal ICH. ICH volume cut-offs highly specific for poor outcome were identified. These findings may have implications for prognosis and clinical trial design.