Diagnostic value of lateral ventricle ratio: a retrospective case-control study of 112 acute subdural hematomas after non-severe traumatic brain injury

Primary Objective: To evaluate correlation between the lateral ventricle ratio (LVR) and the risk of conservative treatment failure (CTF) among patients with acute subdural hematoma (ASDH) after non-severe traumatic brain injury (TBI), we retrieved from the hospital database and performed a retrospective analysis of 1339 cases with TBI treated during the 2008-2016 period. Methods and Procedures: 112 patients with ASDH, GCS >= 9 and initial conservative treatment were enrolled. They were divided according to the final treatment method applied (surgical or conservative). Clinical and radiological data was evaluated. We used ROC curve analysis and multivariate logistic regression model to identify risk factors of CTF. Main Outcomes and Results: LVR higher than 1.48 calculated on admission CT scans was the strongest predictor of CTF, with sensitivity of 78.9% and specificity of 93.5% (AUC: 0.774-0.994). LVR, prolonged prothrombin time and coexisting traumatic subarachnoid hemorrhage were independent risk factors. Conclusions: Despite limitations, study results support the view that patients after non-severe TBI with ASDH and with lateral ventricle asymmetry, defined as LVR> 1.48, require surgical treatment. LVR seems to be indirect, but still the closest method to quantify intracranial compliance. Thus, in the selected group of patients without clinical symptoms of critically diminished compensatory reserve, LVR could indicate those who need a surgical decompression.