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Biomedical subjects

K Willson

Publications and source records attributed to K Willson.

8 recordsLinked to original sources

Strontium-90 as an indicator of time since death: a pilot investigation.

The results of a pilot investigation are presented. The study aimed to show that the presence of radioactive strontium-90 in human bone could be used as evidence of active uptake during life. In this way the time since death of the individual could be identified as occurring before or after the date when atmospheric levels of radioactive strontium were at a peak in the early 1960s. The results of this initial investigation were encouraging but further detailed analysis is required on a substantially larger sample of material spanning a more controlled time period.

Bone and Bones

Quantitative sonography of muscle.

Ultrasound imaging allows detection of pathologic change in muscle on the basis of increased strength of echoes. With current commercial equipment, however, there is no method of quantitation of the echoes representing muscle, and there is lack of uniformity in scanning methodology. We describe a specially constructed scanning system, designed to access the raw echo data directly from the ultrasound transducer, and allow display and measurement of the echo signals on a computer. In a study of 38 boys with Duchenne muscular dystrophy, aged 1 to 11 years, who had an ultrasound scan of the thigh muscle, 32 (84%) had abnormality on quantitation of the ultrasound echoes. The quantitative techniques we describe could easily be incorporated into the design of ultrasound scanners.

Adolescent

Familial partial 14 trisomy.

Four children in the same family have 47, +der (14), t(9;14) (p24;q21). Their mothers are sisters with 46,XX,t(9;14) (p24;q21). Clinical features of the children are similar to those of others reported to have partial 14 trisomy.

Abnormalities, Multiple

A combined ultrasonic linear array scanner and pulsed Doppler velocimeter for the estimation of blood flow in the foetus and adult abdomen--I: Technical aspects.

A method is proposed for estimating the volume blood flow of deep lying vessels in the foetus and in adult portal vein and renal vessels. The equipment combines a 3.5 MHz linear array scanner with a 2 or 4 MHz pulsed Doppler. The pulsed Doppler tranducer is connected to the linear array by two movable arms. A real time spectrum analyser is used to process the Doppler signals. A water bath was used to perform an in vitro calibration of the complete system and to adjust the registration of the Doppler sample volume with the echo picture. Several possible inaccuracies in vessel diameter measurement are discussed and the mean of several caliper measurements described by Eik-Ness (1982) is used. Time Motion is thought to be the better method but is more complicated in practice.

Adult

A combined ultrasonic linear array scanner and pulsed Doppler velocimeter for the estimation of blood flow in the foetus and adult abdomen--II: Clinical evaluation.

A combined pulsed Doppler and linear array scanner is used to measure volume blood flow in 75 aortas and 45 umbilical veins of foetuses in the 3rd trimester. The mean aortic flow was 277 ml/min/kg and the mean umbilical venous flow was 122 ml/min/kg. Mean flow in the portal veins of normal subjects was found to be between 0.6 and 2.0 l/min. Clear signals were obtained from the adult kidney but no volume flow calculation has yet been attempted. The use of a spectrum analyser is considered fundamental to the accurate interpretation and processing of the Doppler signals. Medical and electronic artefacts are described which would not be detected without the use of an analyser.

Adult