An automatic method that can transform a sequence of tomographic image slices into an isotropic volume data set is described. In this method, correspondence is established between points in consecutive slices, and then this correspondence is used to estimate data between the slices by linear interpolation. The method takes advantage of the fact that consecutive slices have small geometric differences, and carries out the search in predicted small neighborhoods. Only points with high gradient magnitudes are used in the search process to increase the reliability of the correspondences. Mismatches that occur are detected and corrected using the continuity constraint in the correspondences. Experimental results showing the matching and interpolation of magnetic resonance slices and computed tomography slices are presented.

Thirty-eight cases of histologically confirmed chondromyxoid fibroma were reviewed and their radiographic features recorded. These findings, coupled with a review of the English-language medical literature, suggest that this rare, benign bone tumor has a characteristic but not specific radiographic appearance and may often mimic more common tumors. Chondromyxoid fibroma may occur anywhere in the skeleton, but almost half of the cases occur around the knee. The possibility of chondromyxoid fibroma should always be considered when a focal bone lesion is evaluated that has geographic bone destruction, a sclerotic rim, lobulated margins, and septation. The diagnosis of chondromyxoid fibroma is most likely when the patient is in the 2nd decade of life.

To evaluate its potential for differentiating benign from malignant breast lesions, digital subtraction angiography of the breast (DSAB) was performed in 23 women with mammographic evidence of disease, and the results were compared with surgical biopsy findings. The DSAB technique employed breast immobilization with modest compression and bolus injection; following the injection of contrast material, 30-40 sequential subtraction images were obtained over a 5-minute interval. The average technical settings were 50 k Vp and 10 mAs, resulting in an estimated radiation dose to the breast of 0.05 mrad (0.5 mu Gy) per exposure. DSAB consistently demonstrated retention of contrast material and abnormal vasculature in malignant lesions but not in benign lesions. In the 22 breast lesions for which there was histopathologic correlation, DSAB correctly categorized eight of nine malignant and 11 of 13 benign lesions. Although this series is small, the initial results of DSAB suggest its potential for differentiating benign from malignant lesions.

No abstract

One hundred and twenty pathologically proven lesions were digitized by computer and recorded on film. Four measures of malignancy, calcification, spiculation, roughness, and area‐to‐perimeter ratio then were mathematically extracted from the digitized xeroradiograph lesions. Using three methods of classification, these were identified by the computer as malignant and benign. Two radiologists then classified the photographed lesions. Comparison of the computer classification and the radiologists' classification using operational characteristic curves showed the computer to perform as well as an expert radiologist.