NSAIds and opioid analgesics administered on postpartum day 3 provided partial headache relief. The next day, a blood patch was performed and intravenous caffeine, fluid and opioid analgesia were given to treat a suspected dural puncture headache. Following diagnosis of postpartum cerebral angiopathy on postpartum day 10, nimodipine was initiated to treat the vasospasm, and the headache was treated with opioid analgesics and toradol, followed by naproxen. The patient also received a 3-day course of intravenous magnesium sulfate.

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.