Most reliable sign of injury to intrathoracic aoa is: (A) Presence of apical cap of pleural fluid, (B) Depression of left main stem bronchous, (C) Obliteration of aoic knob contour, (D) Funny looking mediastenum
Answer is C. Answer- C. Obliteration of aoic knob contourThe most reliable of these signs for the blunt aoic iniury is loss ofthe aoic knob contour.