This paper describes a high resolution electron microscopy study of thorotrast in human tissues. Specimens were prepared from autopsied and biopsied liver samples, and from a surgically removed Thorotrast granuloma taken from patients. Lattice images were taken by a high-magnification X 380,000 at 200KV with an analytical electron microscope. The lattice distance of Thorotrast was 3.2A, which is identical with the lattice distance of Th02 (1,1,1) face. Direct imaging of the crystal lattice gives useful information about the structure and relative orientations of microcrystallites in tissues.

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Various survival curves and prognostic factors of the patients with carcinoma of the pancreas were investigated. Clinical data of 79 patients who had been treated by multimodal methods, separate or combined therapy of surgery and intraoperative radiotherapy(IOR) at two institutions (Chiba Cancer Center Hospital and Tsukuba University Hospital) were collected utilizing the same protocol.
There could not be found any significant difference between the survival curves of two institutions. The comparisons of survival curves for patient groups classified by treatment modalities, on the other hand, showed significant differences at the following three cases, control versus IOR, control versus surgery and IOR versus surgery. However, among these patient groups categorized by TNN staging, the differences of survival surves of each group were not significant statistically except the case of control versus IOR in stagelV patients and the total of all stages.
A multivariate analysis of multidimensional quantification I was performed to evaluate the relative contributions of nine selected prognostic factors to patient survival. The three most important prognostic factors affecting survival were performance status, TNM stage and sex. Four other factors, such as tumor size, tumor site, treatment modality and boost irradiation, were found to have relatively minor contribution, but they were of great importance when considered independently. There was no prognostic significance as for the remaining two factors, age and institution.

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New method is proposed for the measurement of the CT slice thickness. This method is to measure the CT number of a traveling material, placed perpendicularly to the slice plane, as a function of the traveling distance. Movement of the rod was controlled using a traveling microscope with an accuracy of 0.5 mm, The rod was inserted from the outside to the inside of the scan plane. CT number of the imaged rod increases gradually, initially from the air CT number, finally to the genuine CT number of the rod. Full slice width is evaluated as the difference of moving distances. As the rod is projected in a parallel way with the detector aperture, the partial volume effect due to the aperture size is no problem. This method provides a direct and accurate estimate of slice thickness. Comparative study has been made with the 45 degree aluminium strip method.

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