Influence of anode-filter combinations on image quality and radiation dose in 965 women undergoing mammography.

PURPOSE: To evaluate how anode-filter combinations influence image quality in and mean glandular dose to breasts of different thicknesses and compositions. MATERIALS AND METHODS: Mammograms were obtained with a molybdenum (Mo) anode and a Mo filter at 26 kVp, a Mo anode and a rhodium (Rh) filter at 27 kVp, or a tungsten (W) anode and a Rh filter at 26 kVp in 965 women. One anode-filter-tube voltage combination was used in the right breast and another in the left. The mean glandular dose to each breast was calculated. RESULTS: Image contrast was highest in the Mo-Mo mammograms. However, depiction of the glandular tissue, pectoral muscle, and skin and subcutis was significantly (P < .001) better with the Mo-Rh and the W-Rh than with the Mo-Mo combination. The average mean absorbed doses to the glandular tissue for W-Rh and Mo-Rh were 50% and 75%, respectively, of that for Mo-Mo. CONCLUSION: Breast thickness is the most important parameter in selection of an anode-filter-tube voltage combination. Compared with Mo-Mo, both Mo-Rh and W-Rh gave good image quality of the mammary gland and a considerably lower absorbed dose. Mo-Rh-27 kVp is recommended for breast thicknesses of 60 mm or less; W-Rh-26 kVp, for breast thicknesses of greater than 60 mm.

Primary leiomyosarcoma of bone. A clinical, radiographic, pathologic-anatomic, and prognostic study of 16 cases.

Sixteen cases of primary leiomyosarcoma of bone are described. The patients, 11 males and 5 females, ranged in age from 9 to 74 years. The annual incidence of this tumor in Sweden was calculated to be 0.09 cases per million. This figure was obtained by reviewing a Swedish series of spindle cell sarcomas of bone of which one quarter (11/44) were diagnosed by us as primary leiomyosarcoma. The diagnosis was based on light- and electron-microscopic examinations using the same criteria as for leiomyosarcoma of soft tissues. Thirteen tumors were located in a long bone of an extremity (nine close to the knee joint) and three in the central skeleton. Radiographically, all the tumors presented as a purely osteolytic lesion, and three patients had sustained a pathologic fracture. In four of six cases angiography suggested malignancy by revealing hypervascularity, irregular tortuous vessels, and diffuse contrast opacification. Contrast-enhanced computed tomography, performed in two cases, showed hypervascular areas within the tumors. Scintigraphy showed a marked increase in radionuclide uptake in all five cases studied. The clinical behavior indicates that primary leiomyosarcoma of bone is highly malignant. Eight patients had died of the tumor and, of the eight patients who were alive at follow-up, two had metastases, and one had been operated on three times for a cutaneous metastasis, which had recurred locally twice. The remaining five patients had been continuously free of disease for 6.5 to 12.3 years.