Evaluation of Value of Computed Tomography Attenuation (Hounsfield Unit Value) Measured along the Dural Venous Sinuses on Non-contrast Computed Tomography Scan in Diagnosing Cerebral Venous Thrombosis

ABSTRACT

context Cerebral venous sinus thrombosis (CVST) previously believed to be an uncommon cerebrovascular event, accounting for0.5–1% of cases of stroke, affecting 1.32/100,000 person/year. CVST is a disease of young adults (<50 years old) predominantlyand is diagnosed based on clinical suspicion with confirmatory neuroimaging.Aims: This study aims to prospectively evaluate the Hounsfield unit (H.U) value of cerebral venous sinus on non-contrastcomputerized tomography (NCCT) scan and to assess its predictive value in diagnosing cerebral venous thrombosis and toevaluate whether standardizing venous sinus H.U value measurements to those of the corresponding internal cerebral arterywould improve diagnostic accuracy.Materials and Methods: In our study, a total of 80 clinically suspected case of CVST were included and NCCT head scan was donethen confirmed by M.R. venography (gold standard). Of 80 cases, a total of 38 cases were diagnosed as CVST on M.R. venographywhich was considered as Group B and rest 42 cases were normal on M.R. venography which was considered as Group A.Statistical Analysis: Average HU and HH ratio were compared using two-tailed t-test, and linear regression analysis wasused to assess correlation between hematocrit (HCT) and HU.Results: Linear regression analysis showed positive correlation between HCT with computed tomography attenuation (HU)among both the groups (P < 0.005). HH ratio (HU/HCT) for cutoff point of 1.645 had sensitivity of 71.1%, 97.6% specificity,and 96.4% PPV. A cutoff value of 1.335 for standardized measurement with internal carotid arteries (ICA) had 71.1% sensitivity,81% specificity, and 77.1% PPV.Conclusion: We conclude that average HU, HH ratio, and standardized with ICA were the best predictor for sinus thrombosis.