[Diagnosis of osteoid osteoma with special reference to angiography, scintigraphy, computerized tomography and magnetic resonance imaging].

Clinical results from 50 patients with an osteoid-osteoma, show that night pain is considered one of the most important symptoms (90%). 88% responded to salicylic acid. The diagnosis can often be made from normal X-rays. Diagnostic problems are especially common in cases of rare, atypical localisations (spine, sacrum, clavicula, talus, calcaneus and the proximal part of the femur). The scintigraphy represents an unspecific but sensitive method of diagnosis in the early stages. The osteoid-osteoma is visible as a "hot spot" or, in the subperiosteal type, as a diffuse accumulation. Angiography is of great importance for preoperative localisation and differential diagnosis. Computer tomography is particularly valuable for localisation in the region of the spine. Magnetic resonance is an excellent method of examination. The three dimensional imaging allows an exact localisation, especially in atypical and difficult localisations. This will be the preferred method of the future, not least because there is no exposure to radiation.