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Biomedical subjects

D J Coleman

Publications and source records attributed to D J Coleman.

At least 145 records · Page 8Linked to original sources
PubMed1975

Isometric, three-dimensional viewing of ultrasonograms.

This report describes a system that allows amplitude information to be used as a third dimension or aspect of display on B-scan ultrasonograms. The relative strength of reflected echoes can be shown on B-scan by means of gray scale, color coding, or on A-scan with amplitude deflection. With this new technique, called isometric display, superimposition of the A-scan trace on the B-scan allows preservation of these amplitude characteristics. The three-dimensional presentation can be rotated around any azimuth to provide isometric viewing of the ultrasonogram. Tissue may then be characterized on a more reliable basis than is permitted by independent analysis of outline and amplitude features.

Eye Diseases↗
PubMed1975

Ocular tumor patterns.

The use of choroidal excavation and vascular pulsations in the ultrasonic diagnosis of tumors has been a helpful diagnostic feature. Evaluation of choroidal tumors is presently performed with A-, B- and M-scan techniques. Solid tumors of high homogeneity produce characteristic hollows or acoustic quiet zones that replace the normal choroidal pattern. M-scan patterns of vascular pulsations are also useful in demonstrating vascularity or choroidal tumors. Color displays accentuate amplitude variations in ocular tumors.

Blood Vessels↗
PubMed1975

A determination of the velocity of ultrasound in cataractous lenses.

The velocity of sound determinations made in this study are the result of measurements accurate to 0.5 m/sec. The velocity of sound in a series of 50 cataractous lenses was found to be an average of 1,629 m/sec, 11 m/sec slower than that of normal adult lenses. The velocity of sound found in a smaller series of child lenses was 1,659 m/sec, 30 m/sec faster than the cataractous adult lens. It is postulated that this represents a trend of decreasing velocity of sound in the lens with increasing age.

Adult↗
PubMed1975

Phakoemulsification with vitrectomy through the pars plana.

Phakoemulsification through a pars plana incision has been performed on 30 patients, as the initial portion of a combined lensectomy-vitrectomy operation. The technical ease of accomplishing lens removal and the reduced stress on the cornea and irido-ciliary area are described.

Cataract Extraction↗