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Biomedical subjects

M Negin

Publications and source records attributed to M Negin.

8 recordsLinked to original sources

A microcomputer based automated, quantitative coronary angiographic analysis system.

Rapid and accurate assessment of coronary artery stenotic severity is important in therapy and understanding of coronary artery disease. Since automated systems minimize prejudice and variations in analysis, we developed an automated, quantitative coronary analysis system utilizing an IBM PC-XT computer. Film images (35 mm) were cine-to-video converted and subsequently digitized by an IBM PC-XT computer. Given an approximate center line, the computer automatically detected edges, corrected for X-ray magnification, and calculated arterial dimensions. On objects of known dimensional sizes, the correlation coefficient between actual and calculated dimensions was 0.996 (p less than 0.01) with a standard error of estimate of 0.07 mm and +/- 3.0% reproducibility. For objects less than 1 mm in diameter, the standard error of estimate was 0.05 mm with +/- 4.1% reproducibility. However, with minimal contrast material (25%), the standard error of estimate increased to 0.20 mm with +/- 7.2% reproducibility. The results indicate that automated, quantitative coronary angiography can be achieved using an inexpensive IBM PC-XT based system, provided that the vessels are adequately opacified.

Adult

Computer assisted analysis of 2-DG autoradiographs.

A computerized image processing system is described that assists the neurobiologists in analyzing data from 2-DG autoradiography by providing for: (1) Rapid fine-scale digitization of gray levels using a TV camera (2) The recognition of and verification of subtle differences in optical density with the aid of color windows (3) the superimposition of the autoradiographic image upon the histological image, so that the activity seen in the autoradiograph can be accurately assigned to anatomically defined structures (4) The production of numerical data suitable for statistical analysis and line drawings suitable for black on white publication (5) The relating of local gray level to a norm for the image as a whole, so as to remove the variability introduced by variations in section thickness, in the amount of 2-DG seen by the brain during incorporation, in level of anesthesia, etc. If the localized darkening in autoradiographic images is being used as an index of localized functional activity rather than as a measure of metabolism, normalization obviates the need to obtain arterial blood samples. These routines permit anatomically accurate numerical analysis of autoradiographs without any constraints on the experimental situation.

Amygdala

Computer Diagnosis of Breast Thermograms.

A computer-based technique was developed for the automated diagnosis of breast thermogram. Eighty-five thermograms were digitized and analyzed, and 23 parameters computed for each thermogram. A statistical decision program, based on a linear discriminant analysis technique, classified the thermograms into normal and abnormal categories. The accuracy of classification was evaluated by several techniques and found to be comparable to that of trained thermographers.

Breast Neoplasms