Biomedical subjects

J Heavens

Publications and source records attributed to J Heavens.

3 recordsLinked to original sources

PubMed1991

Variation between femurs as measured by dual energy X-ray absorptiometry (DEXA).

It is commonly assumed that there is minimal variation between the hips in an individual, but is densitometry of one femur representative of the other? We performed bone mineral density (BMD) measurements of both hips using a Hologic QDR 1000 densitometer. There were 110 patients, all of whom were right handed, and three main groups of subjects: (1) normal volunteers (n = 36); (2) subjects with known hip pathology (n = 36); (3) subjects with medical conditions not affecting the hip (n = 38). The mean age of the subjects was 46 (21-87) years and a standard analysis protocol was followed in all patients. The coefficient of variation (COV) for femurs was 0.9-3%, depending upon the region studied and the BMD. The left femur had a greater BMD 48% of the time and there were variable differences between femurs in each group studied. While the greatest differences were found in people with unilateral hip pathology, all groups had mean differences greater than the COV. It may be acceptable to study only one hip, but the large variation between femurs in individuals should be borne in mind when interpreting data.

Absorptiometry, Photon↗

PubMed1990

The range of bone density in normal British women.

A study to determine the range of bone density in British females was carried out on a group of 165 normal women. The results showed an increase in mineral content with peak values occurring in the fourth decade (mean 1.06 g/cm2; 95% confidence limits 0.783-1.343) and subsequent decline with increasing age. There was no significant effect from any risk factor but strict exclusion criteria were applied. The results from each age group were compared with those from the USA and showed a difference in the timing of peak bone density (third decade for the USA). Age-matched, clinically well-defined normal controls should be used for comparison with groups of patients in future studies.

Absorptiometry, Photon↗

PubMed1989

Ventilator-dependent children.

The issue of the ventilator-dependent child is a relatively-new one in Australia. Ventilator-dependent children pose complex and unique ethical, medical, economic and psychological problems. The experience of two Australian centres that are involved with the care of ventilator-dependent children is reported. Most of these children now are being cared for at home. Aspects of home care are outlined. After the initial period, the technical aspects are not a problem for most parents for whom the major issues are the provision and funding of nursing support. The complex ethical issues that are involved are discussed. It is concluded that undergoing ventilation at home rather than in a hospital appears to make the best of an otherwise almost-intolerable situation for ventilator-dependent children, but that much more information is required about the outcome for these children and the long-term psychosocial impact of this treatment.

Adolescent↗