Storage phosphor and film-screen mammography: performance with different mammographic techniques.

The aim of this study was to compare the image quality of storage phosphor plates with that in screen-film radiograms in mammography. Two anode/filter combinations were also compared--Mo/Mo and W/Rh. S Storage phosphor plates, generation IIIN (Fuji, Tokyo, Japan) and a conventional screen-film system (Kodak, Rochester, N. Y.) were evaluated using two mammographic units. One unit had a 0.6-mm focal spot, an anode/filter combination of Mo/Mo and no grid (AMo); the other had a 0.3-mm focal spot, a grid, and two possible combinations of anode/filter Mo/Mo (BMo) and W/Rh (BW). Simulated tumours and microcalcifications were randomly positioned in an anthropomorphic breast phantom (RMI model 165, no. 210-009, Radiation Measurements Inc., Middleton, Wisconsin). The image quality was evaluated using a modified version of receiver operating characteristics analysis. Five observers evaluated 300 films and 300 hard copy images each. Radiation doses were also determined. The image quality of the conventional screen-film images was significantly better than that for the storage phosphor plate mammograms. The BMo system rated best, for the detection of both tumours and microcalcifications, although it was not significantly different from the BW system. Systems BMo and BW rated significantly better than the AMo system for both image receptors studied. The mean absorbed dose was twice as high for the BMo system as for the AMo and BW systems for both conventional and digital technique. The mammograms produced with the screen-film combination gave a significantly better detectability than the storage phosphor plates used in this study. Substantial dose reduction could be achieved using an anode/filter combination of W/Rh instead of Mo/Mo with no significant loss of information in the images.

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.

Intraarticular pressure during operation of cervical hip fractures.

The intraarticular pressure was measured during nailing of femoral neck fractures in 21 patients. A three-flanged nail or three screws were used randomly. During traction and inward rotation of the leg, the intracapsular pressure increased over diastolic values, but as soon as the lateral cortex was penetrated, the pressure dropped. The hammering of the nail did not increase the intraarticular pressure.

Cholangiocarcinoma in a patient with biliary cysts.

A 15-year-old girl with multiple intra- and extrahepatic biliary cysts is presented. At a primary laparotomy a massive dilatation of the choledochal duct was found and a choledochocysto-duodenostomy was made. Initially the patient recovered but 1 1/2 years later a mass reappeared under the right costal arch. At a second laparotomy multiple neoplastic changes were found on the right and left liver lobes. Histologic examination of biopsies from the liver showed the picture of a cholangiocarcinoma.