Abstract P243: Identifying Cerebral Venous Thrombosis Through Administrative Data: Icd-10 Case Ascertainment Depends on Clinical Context

Background: Recent reported population-based rates of cerebral venous thrombosis (CVT) are higher than in older studies, though the context of these diagnoses is not well-defined. To better understand these trends, we examined the accuracy of administrative codes ( ICD-10 ) for CVT in different clinical scenarios. Methods: Cases of CVT presenting to a tertiary center between 2008-2018 were identified in two ways: free text search through all hospital electronic radiology reports regardless of modality and body part and any ICD-10 discharge codes (see Table 1). Electronic medical records were reviewed to verify diagnoses of CVT and their clinical context (Figure 1) to calculated Positive Predictive Value (PPV) of ICD-10 codes. Additionally, sensitivities of ICD-10 codes were calculated against all CVTs identified using either searches that were verified on chart review as the gold standard. Results: There were 289 confirmed cases: 239 new diagnoses, 204 of which were acute events. Only 75 cases (37%) were new, symptomatic CVTs not provoked by trauma or structural processes. Sensitivity and PPV for ICD-10 codes depending on clinical context is reported in Table 1. Conclusion: The majority of CVT identified at our institution were incidentally diagnosed in context of intracranial processes such as trauma, surgery, infection, or masses; 37% were symptomatic, non-structural incident diagnoses. Our findings have implications in interpreting CVT rates identified through administrative data, as the management and prognosis of CVT may differ based on clinical context.