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The diagnostic quality of roentgenographic images transmitted by interactive television was evaluated. A series of 100 kidney, ureter and bladder, chest, and bone radiographs were read individually by five radiologists, both on direct viewing and on viewing a monitor image of the television signal. The latter was transmitted by microwave a distance of 28 miles, including four transmission legs. Analysis in terms of receiver operating characteristic curves and critical tables indicated that the television interpretations were of acceptable accuracy, in view of the participants' inexperience with teleradiology.

In order to understand and evaluate fully the composition of the radiologic report, an experiment was performed in which eight readers each read the same 100 chest radiographs. The reports were dissected into individual statements, each of which was analyzed for accuracy, statement type (descriptive or etiologic), confidence, and specificity. In addition, each report was evaluated for stylistic factors of succinctness, orderliness, and the use of supplemental comments. Detailed analysis showed the radiologic report to be a series of largely descriptive statements in which confidence level, specificity, and orderliness were associated with the presence of errors in film interpretation. These factors can serve as important markers for identifying error-laden films. The use of specific, etiologic diagnoses in these film readings was limited. The composition of the report was not related to the length of radiologic training beyond the first year of residency. The implications of these findings concerning report composition in light of present day radiologic practice and new, automated radiologic reporting systems were discussed.

Good technique management is an imperative in modern, efficient departmental routine and patient care. The control of processor efficiency and generator output, along with the production of comprehensive technique charts are factors that contribute to this effective management. They fall well within the responsibility area of the radiologic technologist and require minimal time in department routine.

A method for absolute calibration of diagnostic x-ray generators is presented and discussed. The method employs a Ge(Li) detector and relies on the direct observation of the onset of fluorescence radiation from scattering foils placed in the primary beam.

Interchange or transfer of radiographic techniques through measurement of penetration quality is discussed. The usefulness of this achievement is verified using an aluminum step wedge. Also, the procedure described provides a method for performance evaluation of kVp compensation on diagnostic x-ray installations.

It was hoped that it might be possible to establish some standard or starting point which could be used by future investigators to judge adequate levels of radiopacity of radiopaque denture-base materials. Aluminum and copper were used to define a suitable radiopacity scale. The scale was represented by two sets of specimens--one of regular outline and uniform thickness, the other of irregular shape and tapering thickness. Radiographs of the chest and abdominal regions of a cadaver were exposed, with the specimens placed on the film side and then on the opposite side of the cadaver. The results showed that it was more difficult to locate the beveled irregular specimens, that there was little difference between the chest and the abdomen with respect to ease of locating the same objects, and that the closer an object is to the film the easier it is to locate. For 95 per cent observability, an object should have a level of radiopacity at least equal to that produced by 0.20 mm. of copper.

The radiologic technologist has three professional obligations: to provide consistent quality radiographs, to use minimum exposures necessary for these radiographs, and to reduce unnecessary costs by maintaining good techniques. Through the development and routine use of standardized techniques, he can assure that the radiologist has radiographs of consistent quality to interpret, the patient receives minimum radiation exposure, and the administration maintains a non-wasteful budget in the radiology department. The technique chart is the key to maintaining radiographic quality from which the rest flow.

The technic and safety aspects of the radiographic evaluation of neonates with RDS are discussed. A study of radiographs taken in an intensive care nursery revealed that densitometric measurements are helpful in distinguishing changes in lung aeration from changes in radiographic quality. The radiation exposure to neonates was 5.1 (SD 2.3) mR per film and 44.9 (SD 39.7) MR per neonate. Limited chromosomal studies revealed no detectable abnormalities. The radiation exposure to the staff was minimal. The low-radiation exposure to the staff and neonates is the result of careful attention to radiation hygiene.