[The bone scintigraphy in eosinophilic granuloma (author's transl)]

The significance of bone scintigraphy using 99mTc-polyphosphate or 99mTc-diphosphate in the diagnosis of eosinophilic granuloma was discussed on the basis of our experience with four cases. The summary is following: 1. On diagnostic procedure of eosinophilic granuloma, it was found that abnormal RI accumulation in the bone scintigram was more marked than that in the ordinary brain scintigram. 2. The bone scintigram of eosinophilic granuloma showed more accurately the extent of skull involvement of cellular infiltration than the plain skull X-rays or brain scintigram. Accordingly, the bone scintigram was helpful for neurosurgeon in planning the operative procedure and determining the extent of removal of the involved skull. 3. The plain skull X-rays show the size of skull defect, and the brain scintigram reveals the size of the size of granuloma per se, as well as soft tissue involvements. We can conjecture the stage of the diseases by comparison between the findings of bone scintigram and those of above procedures: plain skull X-rays and brain scintigram. Viz, the bone scintigram showed more extensive areas of RI accumulation including the surrounding cellular infiltration in the acute stage, but the same size of the lesions shown by the ordinary brain scintigram and plain skull X-rays is chronic stage. Furthermore, we discussed the possibility of the differential diagnosis between eosinophilic granuloma and other neoplastic bone diseases, such as intracranial metastatic tumors and multiple myelomas etc., by further experience with the bone scintigram.