THE ROENTGEN DIAGNOSIS OF TAKAYASU'S ARTERITIS.

Abstract

Until ten years ago, Takayasu's arteritis was considered a relatively uncommon entity. A review of the Cumulated Index Medicus for the past three years, however, discloses some 60 papers on the subject in the world literature. The roentgen diagnosis of this disorder has become more reliable with the increasing availability of the proper equipment and technology for aortography. Many terms have been applied to this condition, the most common being Takayasu's arteritis, brachiocephalic arteritis, branchial arteritis, and pulseless disease. It must be classed as a subdivision of the aortic arch syndrome in which the main finding is obliteration of the brachiocephalic pulses. Atherosclerosis, syphilitic aortitis, and Takayasu's arteritis in this order are the most common (7). Other less common causes are arterial embolism and thrombosis, dissecting aneurysm, the thoracic-outlet syndrome, congenital coarctation, pseudoxanthoma elasticum, thromboangiitis obliterans, polyarteritis nodosa, and trauma. All have specific clinical and laboratory findings and usually are not difficult to differentiate. Takayasu's disease is found most commonly in young adults, with females predominating roughly 10 to 1 (10). Originally, the majority of cases were described in Japan, and later a large number of reports came from Sweden and other Scandinavian countries (1, 2, 8, 14). Cases have also been recorded in China, Europe, the United States, and India (8). Symptomatically, complaints are referable to the brain, eyes, and upper extremities secondary to ischemia in these areas. The most constant laboratory finding is an elevated erythrocyte sedimentation rate (6). The clinical aspects may vary from case to case (7). The exact etiology is unknown, but the condition is generally classed among the diseases of autoimmunity. Basically it is felt to be a hypersensitivity phenomenon, although the evidence is indirect (7). Pathologically, the process involves chiefly the aortic arch and its proximal branches, although occasionally changes in other vessels have been reported, as in the abdominal aorta and the popliteal and pedal arteries (1, 4, 14). The condition is chronic, progressive, and inflammatory, characterized by a panarteritis leading to fibrosis and resultant obliteration of the vessel lumen. Thrombosis is a frequent complication (6). Atheromatous plaques are formed (10), and there may be secondary calcification (7). Thus, in its late stages, pathological distinction from primary atherosclerosis may be difficult if not impossible. Radiographic findings reflect the gross pathologic changes. Plain films of the chest may be normal or may show aneurysm formation, arteriosclerosis with calcification, or secondary cardiac changes. Rib notching has been described, caused by dilated intercostal arteries secondary to subclavian obstruction (6). Aortography is the most valuable radiographic technic in the evaluation of this problem.