Classification of traumatic injury to the dural venous sinus using CT venography

Abstract Background and Purpose Cerebral venous sinus thrombosis (CVST) is an underrecognized cause of morbidity in acute traumatic brain injury (TBI). Radiologic diagnosis is challenging in the setting of concurrent extra‐axial injury and a lack of standardized diagnostic criteria. The prevalence of traumatic thrombosis versus compression is unknown. Treatment with anticoagulation is often determined by the appropriate classification of the type of traumatic venous injury. Methods We developed a two‐part radiologic grading method for standardized assessment of traumatic CVST based on (1) the degree of flow limitation through the affected sinus and (2) the location of venous pathology (ie, external compression vs. intrinsic thrombosis) based on computed tomography venography. We applied this grading method to a retrospective cohort of TBI patients presenting to a Level 1 Trauma center. Chart review was performed to identify potential clinical correlates. A senior neuroradiologist graded the entire cohort and a random subsample was selected for blinded rating by two independent neuroradiologists. Results Seventy‐six of 221 patients were identified for inclusion after excluding nontraumatic mechanisms. Seven unique grades were employed to characterize the full extent of venous injuries. The plurality of patients from the cohort (43/76 = 43.4%) suffered compressive injuries. Inter‐rater reliability was moderate for the combined grade, kappa = 0.48, p <.05, and substantial for the flow limitation component, kappa = 0.69, p <.05. Conclusions We introduce a standardized two‐part classification system for traumatic venous sinus injury with moderate‐substantial inter‐rater reliability. Compressive injuries were more common than thrombotic injuries. Further prospective work is needed to validate the clinical significance of this classification system.