[Medical X-ray dryview photography and digitized diagnostic technique].

This paper introduces briefly xeroradiography, computed radiography system, x-ray dryview laser imaging series system and its products, digitized diagnostic technique, as well as the electronic radiography etc.

Feasibility of a large area x-ray sensitive vidicon for medical fluoroscopy: signal and noise factors.

A large area x-ray sensitive vidicon is being investigated as an alternative to the x-ray image intensifier and television camera combination for medical fluoroscopy. Signal generation in an x-ray vidicon involves an x-ray photoconductive layer whose surface is scanned by an electron beam. The single x-ray to electron conversion stage of the x-ray vidicon offers a greatly improved modulation transfer function (MTF) over the x-ray image intensifier. This superior MTF allows signal and x-ray quantum noise at high spatial frequencies to be passed to the preamplifier with less attenuation. In cardiac cine applications this would allow quantum noise limited operation at higher spatial frequencies than is possible with the x-ray image intensifier system.

[Apparatus for medical electroroentgenography]. / Apparaty dlia meditsinskoi élektrorentgenografii.

The paper provides a brief assessment of the development of electric X-ray as a tool for medical examinations and a detailed consideration of the new development - an (See Journal) automatic electric X-ray device.

[Xeroradiography and digital luminescence radiography in the study of the technics of manufacturing ancient ceramics. The advantages and limits]. / Xeroradiografia e radiografia digitale a luminescenza nello studio delle tecniche di manifattura della ceramica antica. Vantaggi e limiti.

This paper reports on the cooperative work of the Department of Radiology of the Catholic University, Rome, and of the Italian Institute for Middle and Far East. The study was aimed at using xeroradiography and digital luminescence radiography for the archeometric evaluation of ancient ceramics and at assessing the imaging potentials of the two techniques. Some manufacturing techniques are reported which were used in the ancient world and societies for pottery making--i.e., coil building (the superimposition of clay rings), paddle and anvil beating and throwing of the wheel. Such techniques leave, on the vessel's wall, clear traces which can be detected by X-ray imaging. After discussing the main semiologic features, we present 4 case studies from the project archive. Each vase underwent xeroradiography and digital luminescence radiography. The former technique was useful in detailing minor phase transitions--e.g., pores and inclusions--while the latter, thanks to both its wide dynamic range and its image processing potentials, was optimal in defining very gradual thickness transitions due to the different techniques used to join the clay parts. By combining the two techniques, the manufacturing technology of the artifacts could be defined. The interactive processing of radiographic images at the system console was seen to be of major importance: it allowed the best results to be obtained thanks to the integration of the radiologists' and archeologists' know-how during the actual analytical stages.

[The stability of the properties of electroradiographic plates for medical x-ray diagnosis]. / O stabil'nosti svoistv élektroradiograficheskikh plastin dlia meditsinskoi rentgenodiagnostiki.

The properties of selenium electrocardiographic plates used for the purposes of medical diagnosis are under discussion. The plates are observed to reveal no noticeable traces of fatigue and to retain constant sensitivity to radiation and radiography in the case of the 5 to 10 minutes' interval between obtaining electroradiograms (ERG) during working hours (7 hours). After the technical resource which is equal to 2000 ERG is over, the radiation sensitivity decreases to 10% and defectiveness does not exceed 25%. The actual expiration date of the plates is between 7 and 9 years without worsening of their properties. The quality of the plates stored for a longer time might deteriorate due to the defect which is attributed to crystallization of the selenium layer.

A subjective study of dental diagnostic utility comparing xeroradiography and film radiography.

This study determined the perceived strengths and weaknesses of xeroradiography, D-speed film, and E-speed film for intraoral radiography. Results indicated that xeroradiography was preferred for the imaging of structures useful in periodontics and endodontics whereas film demonstrated a low level of image artifacts and was judged to be better for the imaging requirements of routine restorative dentistry. D-speed film was rated higher than E-speed film. These subjective assessments are similar to previously reported pilot studies but differ from previously published objective studies, which showed no significant difference between the three imaging techniques. Although there are substantial subjective differences between xeroradiography, D-speed film radiography, and E-speed film radiography, all the techniques provide more than the threshold level of necessary diagnostic information and all techniques portray adequate information for evaluation of common abnormalities encountered in the oral cavity.

A comparison between xeroradiographs and conventional radiographs as an aid in root canal therapy for maxillary molars.

The purpose of this study was to compare the quality of images obtained with dental xeroradiography to that obtained with conventional dental radiography during performance of root canal therapy on maxillary molars. For each step requiring radiographic information during endodontic treatment of 12 maxillary molars, a conventional radiograph and a xeroradiograph were made. This produced four pairs of images for each tooth treated as follows: (1) preoperative, (2) initial files for length determination, (3) master cones fitted, and (4) completed obturation of the root canal systems. The same x-ray machine was used as the source of radiation for all exposures with a setting of 70 kVp and 15 mA and with near identical projection for each pair of images achieved through use of a modified film holder and a custom positioning occlusal index made for each patient. Exposure time for the radiographs was 60 impulses (1 impulse = 1/60 second) and for the xeroradiographs it was 42 impulses. Images of structures and items important in endodontic diagnosis and treatment were rated as unacceptable (0), poor (1), adequate (2), or optimal (3) by four independent evaluators. Analysis of data showed the following: images of bone trabeculae, periodontal ligament spaces, root morphology, root apices, and fine bony abnormalities were judged to be significantly better in the radiographs than in the xeroradiographs (p less than 0.01) whereas there were no significant differences in image quality of pulp chamber morphology, root canal morphology, metallic measuring instruments, or endodontic filling materials.

[Xeroradiographic scanning in clinical oncology]. / Elektrorentgenoskanirovanie v klinicheskoi onkologii.

A combined method of xeroradiographic scanning (ERS) was used for the recognition of tumors of different organs. Altogether 645 cancer patients were investigated: 98 with head and neck tumors, 102--with pulmonary and mediastinal tumors, 254--with liver tumors, 86--with renal tumors, 52--with bone tumors, and 53--with prostatic tumors. Special methods of investigation and tumoritropic radiopharmaceuticals 75Se-methionine, 67Ga-citrate, 85Sr, 113In, 99Tc, etc. were used. Statistical data processing was done using Olivetti computer M-24. ERS was shown to be the most effective method for the detection of cancer of the lung mediastinum (90%), head and neck (89%), and prostate (89%). The method is particularly valuable for tumors developing in anatomical regions inaccessible for examination, biopsy, and x-ray findings are not sufficiently clear. The use of ERS excludes possible errors in diagnosing disease on the edges of an organ, especially in liver and kidney investigation. The method also proved to be valuable for the assessment of therapeutic efficacy and correction of fields of irradiation.

Use of a "sandwich" technique to control image geometry in clinical studies comparing intraoral xeroradiographs and E-speed films.

A method of superimposing a film on a xeroradiographic (XR) cassette for simultaneous intraoral exposure is evaluated for use as an imaging technique in clinical studies comparing Ektaspeed film and XR images. Sandwich images were indistinguishable from those produced by conventional technique. Pilot studies were conducted with 104 patients who had symptomatic dental problems. No significant differences were found in diagnostic usefulness or image quality between XR and film radiographs when sign test analysis was used. The sandwich technique yielded film and XR images with duplicate image geometry while reducing patient exposures to one half of that used in conventional image comparison protocols.

A clinical comparison of xeroradiography and film radiography for the detection of proximal caries.

Xeroradiographs and conventional film radiographs (D- and E-speed) were compared in a clinical study with the use of 1 complete-mouth radiographs for (1) the presence of interproximal caries and (2) the determination of the depth of interproximal caries with the use of 200 tooth surfaces. In addition, an analysis of correct classification rates making a comparison of the same techniques was conducted. The results with the use of ROC analysis indicated that when a comparison was made of xeroradiography and D- and E-speed film, all techniques were equally useful. A broad range of observer ROC area values was found, indicating that diagnostic performance varies greatly with observer. The results of the diagnostic decisions made on carious surfaces versus noncarious surfaces indicated that all techniques tested were similar: 90% correct for noncarious surfaces and 77% correct for carious surfaces.