Aortic Arch Syndrome and Polymyositis with L.E. Cells in Peripheral Blood

MEDICAL MEMORANDA 71 *~~~~~~~~~~~~M and no mural thrombus was present.Both inkternal carotid and vertebral arteries were removed in their entirety.A saccular aneurysm of the right internal carotid sinus 2.5 by 1.5 cm. was found (see Fig.).Sections through the aneurysm showed that the lumen was completely obliterated by laminated thrombus; microscopic examination of the wall of the aneurysm revealed atheromatous thickening and Close-up of right carotid bifurcation, showing saccular aneurysm of right carotid sinus.areas of thinning.The thrombus varied considerably in structure, some areas being organized while others appeared to be recently laid down.The innominate artery and right carotid artery proximal and distal to the aneurysm showed no luminal narrowing, and no stenosis was found at any poin.t in the left carotid system.Neither subclavian artery showed narrowing, but both vertebral arteries were severely stenosed at their origins, less than half the diameter of the original lumen being preserved.No other sites of thrombosis and no ulcerating atheromatous lesions were seen at any point in the carotid and vertebral systems.Brain.The right cerebral hemisphere was softened and