Search PubMed⌕ Search

Biomedical subjects

M K Benson

Publications and source records attributed to M K Benson.

At least 73 records · Page 4Linked to original sources
PubMed1978

Bronchial responsiveness to inhaled histamine and isoprenaline in patients with airway obstruction.

In order to examine the hypothesis that bronchial reactivity to non-specific constrictor stimuli is influenced by the resting tone of the bronchial smooth muscle, the airway responses to inhaled histamine solution and inhaled isoprenaline were measured in 19 patients with airway obstruction. There was a significant positive correlation between the size of the constrictor response to histamine and the dilator response to isoprenaline (r = +0.83; p less than 0.01) as measured by changes in specific airway conductance. Patients with asthma showed greater bronchial reactivity to both histamine and isoprenaline than those with chronic bronchitis, although some patients had changes intermediate between the two extremes.

Adult↗
PubMed1977

The use of 99mc-EHDP as a scanning agent in the detection of metastases from osteosarcoma.

The early detection of metastatic spread in sixteen patients with osteosarcoma has been studied over a twelve month period, comparing the techniques of bone scanning and radiography. In only two patients were we able to demonstrate changes suggestive of pulmonary metastases any earlier with a 99mTc-EHDP scan than with chest radiographs and one of these resolved spontaneously. However, the bone scan did accurately delineate the extent of the primary tumour and may, therefore, be helpful in deciding the level of the amputation and the response of the patient to treatment, particularly now that chemotherapy and immunotherapy are frequently used in the management of the disease.

Adolescent↗
PubMed1977

Bronchial reactivity: interaction between vagal stimulation and inhaled histamine.

The interaction between the effects of vagal stimulation and inhaled histamine on the bronchi was studied in anesthetized dogs. Reactivity was assessed by measuring changes in bronchial caliber visualized with tantalum bronchograms. In seven vagotomized dogs the bronchoconstrictor response to a combination of electrical stimulation of the vagus nerves and inhaled histamine solution produced a mean reduction in airway diameter (Daw) of 2.21 mm which was significantly greater than the additive results of the two stimuli applied separately (mean decrease in Daw 0.29 +/- 0.91 mm). In three dogs the effect of vagal stimulation was to produce a shift in the dose-response curve to inhaled histamine. These results indicate that the effect of the base-line bronchomotor tone must be considered in the evaluation of the effect of vagal blockade on airway reactivity. An increase in the resting degree of bronchomotor tone may contribute to the hyperreactivity observed in patients with asthma.

Aerosols↗
PubMed1976

The pelvic osteotomy of Chiari: an anatomical study of the hazards and misleading radiographic appearances.

The medial displacement osteotomy of Chiari has an established place in the management of older children and adults with severe hip dysplasia. The results claimed for the operation are, however, variable. There have also been reports of sciatic nerve lesions. In this study ten cadavers were operated upon. Chiari osteotomy was performed upon five, and five acted as controls. The hemipelvis was removed from each cadaver; each specimen was deep-frozen and sectioned transversely. The distance of the sciatic nerve from the nearest bony point was measured in each section and the results were recorded graphically. A further radiographic and photographic study was performed to determine whether apparent displacement at the osteotomy might be misleading. The conclusion was drawn that the sciatic nerve is angulated at the osteotomy and further endangered by the risk of bone splintering at the sciatic notch. The radiographic study suggested that some poor clinical results may be explained by a radiological artefact, because there is a tendency for the osteotomy to hinge posteriorly at the sciatic notch opening anteriorly like a book. Radiographs may suggest excellent medial displacement whereas in fact the femoral head is very poorly covered.

Adult↗
PubMed1975

Metal sensitivity in patients with joint replacement arthroplasties.

A high incidence of unexpected metal sensitivity was found in patients with metal-to-metal (McKee) hip arthroplasties. Patients with metal-to-plastic (Charnley) prostheses had no greater incidence of metal sensitivity than a control group awaiting operation. If metal sensitivity does occur loosening of the prosthesis may be a complication.

Aged↗
PubMed1975

Bronchial hyperreactivity.

Bronchial hyperreactivity is characterized by increased responsiveness of bronchial smooth muscle to non-specific constrictor stimuli. Tests used in assessing airway calibre are influenced by a number of factors and should be regarded as providing a qualitative rather than quantitative index of reactivity. One important determinant of bronchial reactivity is the resting state of the airways. An increase in resting bronchomotor tone either by the direct action of spasmogens or by the autonomic nervous system may potentiate a subsequent constrictor stimulus. Bronchial challenge may help in the diagnosis of asthma in patients with normal lung function at the time of testing.

Airway Obstruction↗
PubMed1975

Nitrogen and bolus closing volumes: differences after histamine-induced bronchoconstriction.

Studies in normal subjects have shown that there is little difference in the size of the closing volume when measured by either the nitrogen methods or a bolus method. In this study we have examined the changes in closing volume following histamine-induced bronchoconstriction. In five normal subjects histamine resulted in a reduction in the vital capacity, an increase in the residual volume, and an increase in the airway resistance. The size of the closing volume measured by a bolus method increased after induced bronchoconstriction (0.52 +/- 0.15 1 to 0.74 +/- 0.17 1). With the nitrogen method the closing volume became smaller (0.51 +/- 0.19 1 to 0.17 +/- 0.17 1). Similar differences between the two methods are demonstrated in patients with asthma. The suggested explanation for these differences lies in the different methods used to establish a concentration gradient of gas in the lung. If there is "air trapping" the nitrogen method may fail to establish a concentration gradient.

Adult↗
PubMed1975

Infection following total hip replacement in a general hospital without special orthopaedic facilities.

Infection following total hip replacement is a serious complication for it is frequently impossible to resolve without removal of the prosthesis. We have reviewed 321 total hip replacements undertaken in a general hospital without special orthopaedic theatres. There were 17 deep infections, nine early and eight late. Athough the diagnosis of early infection is usually not difficult, the differentiation between late infections, mechanical failure and metal sensitivity may be a problem. This paper discusses the use of ESR, radiographs, isolation of pathogenic organisms and bone scanning in reaching the diagnosis of infection of the hip. There is possibly a parallel between prosthetic infection and subacute bacterial endocarditis. Therefore all intercurrent infections and episodes of trauma should be given an adequate course of a broad spectrum antibiotic. Sterile air and laminar flow systems are discussed and compared with prophylactic antibiotics, both systemic and local, in attempting to reduce the overall rate of infection following total replacement of the hip.

Adult↗
PubMed1975

The clinical syndromes and surgical treatment of thoracic intervertebral disc prolapse.

Doubt remains as to the safest surgical approach to the prolapsed thoracic intervertebral disc. Laminectomy, lateral rhachotomy and the transthoracic approach all have their protagonists. Twenty-two patients from the National Hospital for Nervous Diseases, Queen Square, and Atkinson Morley's Hospital have been reviewed. Their clinical presentation is discussed and the ancillary aids to diagnosis assessed. The diagnostic value of disc space calcification is stressed, and the use of air myelography as an adjunct to positive contrast myelography is noted. Fifteen patients were subjected to laminectomy, and seven to lateral rhachotomy. Each group contained patients with a wide range of neurological deficit. Six of the patients who underwent laminectomy were improved, two were unchanged, six deteriorated and one died. Of the patients who had lateral rhachotomy, six were improved, one was unchanged and none deteriorated. The conclusion is drawn that lateral rhachotomy is a safer procedure.

Adult↗