The empty delta sign.
Lee
Emil J Y
EJ
Department of Radiology, University of British Columbia, Vancouver, Canada.
D003392:Cranial Sinuses / Q000000981:diagnostic imaging*; D006801:Humans; D011856:Radiographic Image Enhancement; D020225:Sagittal Sinus Thrombosis / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed