(b) Graphic depiction of the “tangential calcium” sign: Red color represents the circumferential wall of the aorta with focal discontinuity at 12 o’ clock position. Dashed white line represents the linear calcifcation that does not conform to the anticipated aortic arch demonstrating the “tangential calcium” sign.
(c) Axial unenhanced CT in a patient presenting with abdominal pain, and fndings of ruptured AAA, with focal discontinuity of the intimal calcifcation in the wall of the aneurysm (curved red arrow) and adjacent linear calcifcation that does not conform to the anticipated aortic arc, the “tangential calcium” sign (straight red arrow). There is also high attenuation stranding anterior to the aorta, consistent with rupture
Ponnatapura, J., Dyer, R.B. The “tangential calcium” sign. Abdom Radiol 44, 2933–2934 (2019). https://doi.org/10.1007/s00261-019-02025-z
