Differentiation of Transverse Sinus Thrombosis From Congenitally Atretic Cerebral Transverse Sinus With CT

Abstract

Background Transverse sinus thrombosis can have nonspecific clinical and radiographic signs. We hypothesized that the novel “sigmoid notch sign” (on head CT) can help differentiate transverse sinus thrombosis from a congenitally atretic sinus among individuals with absent signal in one transverse sinus by magnetic resonance venography (MRV). Methods We retrospectively evaluated 53 subjects with a unilaterally absent transverse sinus signal on MRV. 11 had true transverse sinus thrombosis and 42 had an atretic transverse sinus. Reviewers were trained in the sigmoid notch sign: “positive” if one of the sigmoid notches was asymmetrically smaller than the other, consistent with a congenitally absent transverse sinus on that side. This sign was scored on CT scans by, two blinded reviewers to determine if signal dropout was clot or atretic sinus. A consensus rating was reached when the reviewers disagreed. Characteristics of the sigmoid notch sign as a diagnostic test were compared to a gold standard of full chart review by an independent reviewer. Results Each reviewer had a sensitivity of 91% (detecting 10/11 clots based on a negative sigmoid notch sign) and specificity of 71-81%; consensus specificity increased to 86% (36 of 42 individuals with an atretic sinus had a positive notch sign, detecting atretic sinuses based on presence of the sign). Conclusion Asymmetries of the sigmoid notches on non-contrast brain CT is a very sensitive and specific measure of differentiating transverse sinus thrombosis from an atretic transverse sinus when absence of transverse sinus flow is visualized on MRV.

Cerebral Venous Sinus Thrombosis Incidence Is Higher Than Previously Thought

“…Incidence was higher than others have found previously published. [1][2][3][4][5][7][8][9][10][11] Including the recent study of Coutinho et al, 1 that demonstrated an incidence of 13 million person-years, which was also substantially higher than expected from previous research. They studied a 3-year period in an organization with comparable access to neuroimaging; however, they identified cases solely using clinical coding.…”

“…[1][2][3][4][5][6][7][8][9][10][11] The low incidence and incongruous presentation of CVT often lead to late diagnosis. [1][2][3][4][5][6][7][8]11 The incidence of CVT has been reported as being between 2 and 5 million per year.…”

“…[1][2][3][4][5][6][7][8]11 The incidence of CVT has been reported as being between 2 and 5 million per year. [1][2][3][4][5][7][8][9][10][11] A recent report suggested a much higher incidence (13 million person-years 1 ). Incidence may have been previously underestimated for several reasons, primarily inaccurate coding and lack of sophisticated neuroimaging.…”

Zerebrale Venen- und Sinusthrombose

“…Insbesondere muss z. B. eine Hypoplasie des Sinus transversus von einer Thrombose unterschieden werden [5]. Intrazerebrale Blutungen finden sich bei 30%-40 % aller Patienten, hingegen sind subdurale oder subarachnoidale Blutungen deutlich seltene [3].…”

Chinese Stroke Association guidelines for clinical management of cerebrovascular disorders: executive summary and 2019 update of clinical management of cerebral venous sinus thrombosis

“…The incidence of CVST is 2-5/10 000 000/year, accounting for 0.5%-1% of all stroke. [1][2][3][4][5][6][7][8][9] Recently, the incidence of CVST has been rising with the advent of diagnostic techniques. Two studies in Iran have reported CVST affects 12.3-13.49/10 000 000/year, 3 10 and another study in Saudi Arabia has shown that CVST affects 70/10 000 000/year.…”