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Biomedical subjects

R D Moseley

Publications and source records attributed to R D Moseley.

At least 19 recordsLinked to original sources
PubMed1986

Population characteristics and absorbed dose to the population from nuclear medicine: United States--1982.

Those in the U.S. population who receive nuclear medicine examinations have been characterized by age and sex. Males received 42% of examinations while females received 58%. More than one-third of the examinations were done on persons older than 64 y of age and more than two-thirds on patients older than 45 y of age. The per caput effective dose equivalent from nuclear medicine procedures in 1982 was 140 muSv (14 mrem); whereas, the per caput age-specific effective dose equivalent to the U.S. population was 50 muSv (5.9 mrem). These can be compared with 2 mSv (200 mrem) from natural background.

Adolescent↗
PubMed1986

Chest radiographs obtained with shaped filters: evaluation by observer performance tests.

The effectiveness of a shaped filter in improving nodule and infiltrate detection was measured by observer performance testing. Seven observers read 152 test radiographs of the chest obtained from human volunteers. Half the test radiographs had target images. Observer performance in detecting nodule or infiltrate images was compared with the shaped-filter system and with a conventional chest imaging system. The results were analyzed using receiver operating characteristic (ROC) techniques and indicate that the filter technique was not significantly different from the conventional technique in infiltrate depiction. Observer performance in detecting nodules was slightly worse on images obtained with the shaped-filter system.

Filtration↗
PubMed1985

ROC and contrast detail image evaluation tests compared.

Using both contrast detail and receiver operating characteristic (ROC) evaluation tests, we evaluated different quality images, produced with different film-screen combinations. ROC curves were obtained for six observers who were attempting to detect lung nodules and pulmonary infiltrates. The contrast detail curves were obtained from images of regular circular test patterns of differing contrast, which had been presented to the observers. Our results indicate that contrast detail tests can be used for relative ranking of image systems prior to detailed ROC testing.

Evaluation Studies as Topic↗
PubMed1985

Thyroid radiation absorbed dose from diagnostic procedures in U.S. population.

According to a 1981 survey of thyroid imaging methods in the United States, radionuclide thyroid scans and uptake studies increased 250%-300% between 1966 and 1981, while the U.S. population increased only 17%. Collective absorbed dose decreased from 18 X 10(6) rad (18 X 10(4) Gy) in 1966 to 13.9 X 10(6) rad (13.9 X 10(4) Gy) in 1981. The decrease was due to the use of iodine 123 and technetium 99m pertechnetate rather than iodine 131 (I-131 was used for 100% of scans and uptake studies in 1966 and 10% and 54%, respectively, in 1981) and also to fewer free-standing thyroid uptake studies (150,000 in 1966 and 33,000 in 1981). Even with reduced usage, I-131 still accounted for 93% of the collective absorbed dose in 1981. If I-131 were eliminated from diagnostic procedures, the annual absorbed dose would decrease to 1.4 X 10(6) rad (1.4 X 10(4) Gy). The number of radiation-induced cancer cases would also be reduced.

Humans↗
PubMed1985

Trends and utilization of nuclear medicine in the United States: 1972-1982.

In the decade 1972-1982, in vivo nuclear medicine procedures in the United States increased from 3.3 million to about 7.5 million per annum. This growth has been the result of a markedly increased frequency in some types of examinations; particularly bone, liver, lung, and cardiovascular imaging. The only type of imaging in which a decrease in frequency has been observed has been in radionuclide brain imaging. Examination of these trends illustrates the difficulty in forecasting, even over time periods as short as 5 years. Competing tests have largely replaced radionuclide imaging in some areas; although in other areas, such as cardiac nuclear medicine, competing technologies appear to have been additive in terms of the frequency of examinations. Comparison with recent data from other countries indicates that the frequency of nuclear medicine procedures in the United States is probably the highest in the world.

Biliary Tract Diseases↗
PubMed1983

Anticrossover emulsions evaluated by observer performance tests.

Observer performance in the detection of pulmonary nodules and infiltrates was measured using film coated with anticrossover emulsion, a recent innovation in radiographic film that is expected to produce sharper images because of improved resolution. Test radiographs of an anthropomorphic phantom were shown to six experienced observers. Radiographs containing pseudonodule and pseudoinfiltrate images were obtained with the anticrossover film and the same type of film without the anticrossover coating. Test images contained single nodules, single infiltrates, or both; approximately 45% of the test radiographs were normal. Individual receiver operating characteristic (ROC) curves were formed, and sensitivity and specificity values were calculated. The results demonstrated an improvement in observer performance with the anticrossover film as measured by sensitivity and the area under the average ROC curves.

Humans↗
PubMed1983

Factors affecting perception of pulmonary lesions.

The authors review some of the factors that influence the perception of pulmonary lesions: the observer and his environment, the film or other image-recording and display media, the lesion and its qualities, and the technique or modality of examination used.

Humans↗
PubMed1982

Cost-effectiveness of stereoscopic radiographs in detection of lung nodules.

Detection of lung nodules was assessed using a series of radiographs which were either normal or showed only one nodule. Stereoscopic pairs were obtained in 26 cases (10 positive and 16 normal). A "singles" series comprising one radiograph from each pair was presented to each observer on three occasions. The pairs were later presented side by side and finally were viewed stereoscopically. The results indicate that a second shifted radiograph improves detection of lung nodules enough to be cost-effective. The shifted radiographs do not need to be viewed stereoscopically.

Cost-Benefit Analysis↗
PubMed1978

Effect of fatigue and alcohol on observer perception.

A test series of chest radiographs containing pseudonodules was used to establish baseline sensitivity, specificity, and accuracy rates for individual observers. This experiment studies the effect of fatigue (as subjectively measured) and alcohol (as measured by blood alcohol levels) on observer perception and performance. The results indicate that the fatigue encountered in the course of ordinary professional activities has no significant effect on diagnostic accuracy. Modest quantities of alcohol may adversely influence diagnostic sensitivity, but the effect is unpredictable. Subjective estimates of the influence of fatigue or alcohol on performance by individual observers are frequently erroneous.

Ethanol↗
PubMed1977

The federal government's impact on radiology.

The areas of involvement by federal agencies which have primary health missions are outlined. The roles of many federal agencies which touch on health peripherally are also discussed.

Financing, Government↗
PubMed1977

Effect of size and position on chest lesion detection.

A test series of radiographs was developed by duplicating normal chest radiographs with superimposed masks containing either a 0.5, 1.0, or 1.5 cm pseudolesion. Nine observers participated in the study. Receiver operating characteristic curves were formed and the responses from radiologists and physicists compared. The accuracy rate for detecting 1.0 and 1.5 cm lesions was 44%; for 0.5 cm lesions, 8%. Lesions located in the upper left quadrant were detected with an accuracy of 56% compared to 29% for those in the lower left quadrant.

Diagnostic Errors↗