Radiological Terrorism

We run the risk that terrorists will decide to detonate an explosive device laced with radioactive materials (a radiological dispersal device, or RDD). If such an attack occurs, it is unlikely that the affected population or emergency responders would be exposed to high levels of external radiation, although airborne radionuclides may present a health risk under some circumstances. However, the effects of radiation and radioactivity are not well known among the general population, emergency responders, or medical personnel. This could lead to unwarranted panic, refusal to respond to the incident, inappropriately delaying or denying treatment to injured victims, and other unfortunate reactions during the emergency phase of any response. During the recovery phase, current regulations may lead to costly and restrictive radiation safety requirements over very large areas, although there have been recent efforts to relax some of these regulations in the first year following a radiological attack. The wide spread of radioactive contamination can also lead to environmental contamination, particularly in low-flow areas and near storm sewer discharge points, but the total radiation dose to the environment should not be excessively high in most locations.     

Radiological aspects of collagen diseases

The collagen diseases, an ill-defined group of clinical entities, have as their basis a generalized alteration of the connective tissue, especially of its extracellular components. They include periarteritis nodosa, disseminated lupus erythematosus, dermatomyositis, scleroderma, rheumatic fever and rheumatoid arthritis. The radiological findings in a series of cases of these diseases were reviewed. In 28 cases of periarteritis, 20 cases showed some abnormal findings in the thorax. These included pleural effusions, pulmonary changes, pericardial effusions and cardiac enlargement. In 32 cases of disseminated lupus erythematosus, thoracic findings were noted in 21. They resembled the changes found in periarteritis. In some 25 cases of scleroderma, diverse radiological findings were noted. These included "cystic" changes in the lungs (one case) and pulmonary "hives." In the intestinal tract esophageal and small bowel alterations were found, both ectatic and stenotic. In the soft tissues of the "pressure areas" variable degrees of calcification were observed. Dermatomyositis is the rarest of the collagen disease group; only one autopsy-proven case is available for study. Chest x-rays taken a year before death showed slight cardiac enlargement. The lungs were clear. In acute rheumatic fever, x-ray examination may disclose pericardial or pleural effusion, and so-called rheumatic pneumonitis; the latter has no specific diagnostic features. Soft tissue swellings may develop around some of the joints. In rheumatoid arthritis, joint changes are numerous and fairly characteristic, and are followed in many cases by fibrous or bony ankylosis and deformities of considerable degree. Awareness of the commoner radiological changes in this entire group of diseases should result in earlier establishment of diagnosis, especially in the more obscure examples.