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Biomedical subjects

D Pycock

Publications and source records attributed to D Pycock.

6 recordsLinked to original sources
PubMed2001

CBIT--context-based image transmission.

Few networks offer sufficient bandwidth for the transmission of high resolution two- and three-dimensional medical image sets without incurring significant latency. Traditional compression methods achieve bit-rate reduction based on pixel statistics and ignore visual cues that are important in identifying visually informative regions. This paper describes an approach to managing image transmission in which spatial regions are selected and prioritized for transmission so that visually informative data is received in a timely manner. This context-based image transmission (CBIT) scheme is a lossless form of progressive image transmission (PIT) in which gross structure, represented by an approximate iconic image, is transmitted first. Each part of this iconic image is progressively updated, using a simple set of rules that take into account viewing requirements. CBIT is realized using knowledge about image composition to segment, label, prioritize, and fit geometric models to regions of an image. Tests, using neurological images, show that, with CBIT, a valuable transmitted image is received with a latency that is about one-tenth that of traditional PIT schemes. Frequently, the necessary regions of the image are transmitted in about half the time taken to transmit the full image.

Artificial Intelligence↗
PubMed1987

Automation of routine clinical chromosome analysis. II. Metaphase finding.

Metaphase finding is an essential activity in chromosome analysis, and there is much to gain from its automation. This paper describes software for automatic metaphase finding developed for use as part of a routine clinical chromosome analysis system, principally for samples from blood and amniotic fluid. Since the metaphase finding and analysis programs were intended to be used widely in clinical laboratories, cost and portability were important design features. The metaphase finder has been implemented on a moderately priced, general-purpose image analyzer (Magiscan 2), which controls a standard research microscope with motorized stage and focus. Metaphases are detected using fast gray-level processing on whole fields of view, followed by binary processing to produce a figure of merit for each detected object. Clinical experience has shown that this ability to rank detected objects on the basis of their suitability for analysis is a critical feature in determining the usefulness of an automatic metaphase finder.

Amniotic Fluid↗
PubMed1981

The magiscan image analyser as a diagnostic aid in cytology.

Many reports in recent years have described the application of image analysis to cervical smear prescreening. This paper describes a complementary approach to automation in diagnostic cytology. In this approach the image analyzer is programmed to automatically scan a slide, measure preselected morphologic features and store the results. Subsequently, the operator selects combinations of measurements for interactive analysis. Using this technique the diagnosis of subtle deviations in cell morphology may be based on a quantitative analysis of cell morphology. We describe the implementation of these techniques on the Magiscan Image Analyser and illustrate the process of analysis using three smears. These smears were routinely diagnosed as negative in one case and as cervical intraepithelial neoplasia (CIN grade II-III) in two cases.

Cell Nucleus↗
PubMed1980

Use of the MAGISCAN image analyser in automated uterine cancer cytology.

A low-cost automatic prescreening system for uterine cancer cytology based on the commerically available MAGISCAN Image Analyser is described. Dispersed hematoxylin-stained samples are viewed with an automated TV microscope. Software has been written to locate cell nuclei at 4 micron resolution and trace each nuclear boundary at 0.5 micron resolution. At least six parameters per nucleus are measured, including intergrated optical density. Cells are classified using a multiparameter look-up table. Analysis rats of 600 cells per minute can be achieved. Because the hardware and much of the software are already available, a high performance:cost ratio can be achieved, resulting in a system that could be cost effective in a laboratory with a throughput of 15,000 smears per annum.

Autoanalysis↗