Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RADIOGRAPHY”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 685 records · Page 38Linked to original sources

Scintigraphy and contrast radiography for epiphora.

During a one-year period 53 patients were referred for the investigation of epiphora. All underwent bilateral dacryoscintigraphy. Following the isotope study the patients had either bilateral or unilateral macrodacryocystography; a total of 66 tear ducts were shown by this procedure. The scintigraphs were more sensitive for obstruction (51/66 systems or 77%) than radiography (33/66 systems or 51%). Normal dacryoscintigraphy was always associated with duct patency on dacryocystography. We have concluded that scintigraphy should always be the first investigation and that, if this is normal, radiography is not necessary. The use of digital subtraction imaging for the lacrimal passages is discussed. It is suggested that this may provide information obtained at present only by combining dacryoscintigraphy with conventional contrast radiography.

Humans↗

Bone scintigraphy and radiography in the early recognition of diabetic osteopathy.

Twenty-seven diabetic patients with clinical evidence of neuropathy were investigated by foot radiography, two-phase bone scintigraphy, biothesiometry and cardiovascular autonomic function testing. Typical signs of diabetic osteopathy on radiography were found in 10 subjects (37%), the degree of radiographic abnormality correlating with the severity of neurological impairment. Furthermore, all diabetics with evidence of severe neuropathy showed some evidence of osteopathy on foot radiographs. In all 10 cases of diabetic osteopathy diagnosed radiographically, abnormalities were shown on scintigraphy. In addition, five other patients showed scintigraphic abnormalities, without corresponding changes on radiography, and in this group the neurological impairment was less severe. Although confirmatory longitudinal studies are necessary, it seems likely that the earliest changes of diabetic neuropathic osteopathy may thus be recognized on bone scintigraphy, at a time when conventional radiographs are normal. This stage of diabetic osteopathy is associated with a lesser degree of neurological impairment.

Adult↗

Chest radiography in the management of breast cancer.

This study was undertaken to assess the utility of chest radiography (CXR) in the management of patients with breast cancer and to devise a suitable imaging policy for such patients. A retrospective analysis was performed of the case notes and the CXRs of a series of 141 patients presenting to this hospital in 1980 with a diagnosis of early breast cancer. Data retrieved covered the entire clinical course to date and included the number of CXRs performed for a clinical reason and the number performed as "routine". Correlation of the result of every CXR requested to subsequent therapeutic decision-making throughout the complete clinical course of each patient was undertaken and the proportion of CXRs initiating a management change, or performed for a clinical reason, out of the total requested was assessed. A total of 1161 CXRs were performed on the 141 patients studied. Of these, only 174 (15%) were undertaken for a direct clinical reason and 987 (85%) were undertaken as part of "routine" follow-up procedures and had no impact on patient management. Four "routine" CXRs (< 0.4%) demonstrated previously undiagnosed pulmonary metastases, in patients with no other history of metastatic disease. Thus, routine chest radiography is not a cost-effective method of monitoring asymptomatic patients with breast cancer for metastasis. It is recommended that outside staging procedures for clinical trials, the CXR is used only to address a clinical problem relating specifically to the thorax. It is anticipated that the cessation of all other chest radiography in patients being followed up for breast cancer at this institution will have significant budgetary implications.

Bone Neoplasms↗

Radiation doses to patients undergoing scoliosis radiography.

In this study we computed the radiation doses associated with scoliosis radiography and investigated how these radiation doses are influenced by the weight of the patient. We recorded the radiographic technique factors of 61 consecutive patients (46 females and 15 males) undergoing scoliosis radiography. A wedge-shaped aluminium filter attenuated the X-ray beam in the "chest region" relative to the "abdomen region". X-ray tube air kerma output factors (microGy mAs-1) and half value layers (HVLs) were determined experimentally for the "chest region" and "abdomen region". The energy imparted to each patient was computed from the air kerma area product, X-ray beam HVL and measured patient thickness. Values of patient effective dose were obtained using effective dose-to-energy conversion factors for specified radiographic projections, taking into account each patient's weight. The median patient age was 17 years, and the median patient weight was 53 kg. Entrance skin air kerma values in the "chest region" were approximately a factor of four lower than those in the "abdomen region". The air kerma values increased by a factor of two when the patient weight increased from 30 kg to 70 kg. Approximately 80% of the total energy imparted to a patient undergoing a scoliosis examination was in the "abdomen region", with the remaining 20% imparted to the "chest region". Energy imparted increased with patient weight, and was approximately 3 mJ for a 30 kg patient and approximately 8 mJ for a 70 kg adult patient. Effective doses showed little correlation with patient weight, with an average-sized patient (50 kg) receiving an effective dose of approximately 140 microSv. Patients undergoing scoliosis radiography receive effective doses that are low in comparison with other types of radiographic examination.

Adolescent↗

Demonstration of correlations between clinical and physical image quality measures in chest and lumbar spine screen-film radiography.

The ability to predict clinical image quality from physical measures is useful for optimization in diagnostic radiology. In this work, clinical and physical assessments of image quality are compared and correlations between the two are derived. Clinical assessment has been made by a group of expert radiologists who evaluated fulfillment of the European image criteria for chest and lumbar spine radiography using two scoring methods: image criteria score (ICS) and visual grading analysis score (VGAS). Physical image quality measures were calculated using a Monte Carlo simulation model of the complete imaging system. This model includes a voxelized male anatomy and was used to calculate contrast and signal-to-noise ratio of various important anatomical details and measures of dynamic range. Correlations between the physical image quality measures on the one hand and the ICS and VGAS on the other were sought. 16 chest and 4 lumbar spine imaging system configurations were compared in frontal projection. A statistically significant correlation with clinical image quality was found in chest posteroanterior radiography for the contrast of blood vessels in the retrocardiac area and a measure of useful dynamic range. In lumbar spine anteroposterior radiography, a similar significant correlation with clinical image quality was found between the contrast and signal-to-noise ratio of the trabecular structures in the L1-L5 vertebrae. The significant correlation shows that clinical image quality can, at least in some cases, be predicted from appropriate measures of physical image quality.

Computer Simulation↗

Survey of posteroanterior chest radiography in The Netherlands: patient dose and image quality.

Council Directive 97/43/Euratom (Medical Exposure Directive) states that member States of the European Union shall promote the establishment and use of diagnostic reference levels for radio-diagnostic examinations. Dose surveys can form the basis for the establishment of diagnostic reference levels. In view of the implementation of the Medical Exposure Directive in the Netherlands, a survey of dose and image quality has been performed for posteroanterior (PA) chest radiography in 2001. In this survey, 25 participants were selected from a list of 175 Dutch hospitals, whereas in a previous PA chest survey (about 10 years ago) participation was voluntary and participants came predominantly from the south-western part of the Netherlands. For conventional screen-film PA chest radiography, the present results for patient dose and image quality are quite similar to those results from the previous survey. The fraction of conventional X-ray systems utilizing lung compensation filters has remained approximately the same. For dedicated digital chest radiography systems, image quality is better than for conventional systems, but doses vary and can assume relatively high values. The results indicate that there are still possibilities for dose reduction, without loss of image quality. The 75 percentile value of the entrance surface dose distribution is approximately 0.13 mGy.

Filtration↗

Comparison between panoramic and periapical radiography in the diagnosis of periapical bone lesions.

The diagnostic accuracy of panoramic and periapical radiography was compared by five oral radiologists who assessed the periapical status of 117 teeth evenly distributed throughout the jaws with a 50% probability that either an osteolytic or sclerotic lesion was present. Receiver operating characteristic (ROC) analysis demonstrated no overall significant difference between panoramic and periapical radiography. However, for sclerotic lesions and for all lesions on maxillary premolars and mandibular molars periapical radiography was significantly superior (P less than 0.001); it was also superior for osteolytic lesions in the maxilla as well as for the lesions on mandibular premolars but with a smaller significant difference (P less than 0.05).

Adult↗

Scottish dentists' use of and opinions regarding bitewing radiography.

This study examined Scottish dentists' claimed use of and opinions regarding bitewing radiography. Information was obtained from a questionnaire sent to all dentists practising in Scotland in 1987 and from national statistics published in the Annual Reports of the Dental Practice Boards in the UK. The response rate to the questionnaire was 72% (926 general dental practitioners and 201 clinical community dental officers). Respondents considered radiography to be of value for the detection of approximal caries, assessment of caries progression and evaluation of alveolar periodontal support. They considered it to be of less value for a variety of other tasks, including detecting occlusal caries, unerupted teeth or calculus. One hundred and fifty-eight dentists (15% of respondents) claimed not to have taken any bitewings of their 12-year-old patients in the preceding year. Those respondents who did claim to have exposed some bitewings said that approximately one-quarter of this patient group had received the examination in the past year. The overall Health Service statistics appear to confirm that the utilization of radiography by dentists practising in Scotland is somewhat lower than that by dentists in England and Wales, a factor which requires further investigation.

Attitude of Health Personnel↗

Radiographic detectability of periodontal diseases. A comparison of perapical radiography with detailed zonography.

OBJECTIVE: To compare the diagnostic accuracy of conventional periapical radiography with detailed zonography using the Scanora system for the detection of periodontal disease. METHODS: We selected for comparison 311 periodontal sites in 165 patients. Five observers independently assessed the periapical radiographs and detailed zonograms for marginal widening of periodontal ligament space, crestal erosion, vertical bone loss, furcation involvement and calculus. RESULTS: ROC analysis revealed no significant differences between the two imaging techniques for either overall or lesion-specific interpretation of periodontal pathology. The sensitivity of periapical radiography was 79%, and of detailed zonography 91% (multiview) and 89% (stereoscopic). Specificities were 82%, 77% and 83%, respectively. CONCLUSION: Detailed zonography performs as well as periapical radiography in the detection of periodontal disease.

Adult↗

Effects of instruction on the knowledge, attitudes and beliefs of dental students towards digital radiography.

OBJECTIVE: To investigate the effects of a course of instruction in intraoral digital radiology on the knowledge, attitudes and beliefs of dental students. METHODS: A questionnaire was administered to dental students at two institutions with (UL) and without (MCG) formal instruction in digital dental radiology, investigating their understanding of the principles of digital radiography, their attitudes to its use in the near future, and on the timing and suitability of the topic in the undergraduate dental curriculum. Differences in the responses between preclinical and clinical students at the two institutions were statistically assessed. RESULTS: The overall response rate was 66% (277) with rates of 52% (103) at MCG and 76% (174) at UL. UL students knew significantly more about digital radiography but they also had some significant misconceptions and differed in their perception of its future role. Most students (93%) believed that digital radiography should be included in the curriculum or offered as an elective course. CONCLUSIONS: Dental students want digital radiology to be introduced into the dental radiology curriculum, regardless of whether it is examined or not. The teaching methods and content of such a course need careful consideration.

Attitude of Health Personnel↗

The influence of the X-ray spectrum at compact bone-titanium interfaces in digital dental radiography.

OBJECTIVES: To determine the optimum X-ray spectrum in digital dental radiography once the dose around an implant and the diagnostic usefulness of the image are taken into account. MATERIALS AND METHODS: A Monte Carlo code (MCNP4B) was employed for computing the dose distribution across the bone-titanium interface. The X-ray spectra used were those met in digital dental radiography; 50-70 kVp, 2 mm Al total filtration, 5 kVp increment. RESULTS: The variation of the ratio of dose with as opposed to without implant against depth reaches maximum values at the bone-implant interface that vary between 2.9 and 3.2. For the same number of photon histories followed, the higher the tube potential setting, the greater the dose both in contact and inside the implant. CONCLUSION: In digital dental radiography, a 60-65 kVp spectrum accompanied by the known 30% reduction in mAs leads to lower dose to the patient for a diagnostically useful image.

Bone and Bones↗

A modified system of stress radiography for patellofemoral instability.

Axial radiographs were obtained under valgus and external rotation stress at 45 degrees of knee flexion with and without contraction of the quadriceps muscle in order to assess the dynamics of patellar subluxation or dislocation. The radiography was performed on 82 knees in 61 patients with patellofemoral instability, and on 44 normal knees. The lateral patellofemoral angle and the congruence angle were measured and compared with the conventional Merchant views. Both parameters showed greater differences between symptomatic and normal knees on the stress radiographs obtained without quadriceps contraction. There was a major difference in the lateral patellofemoral angles between the groups, which clearly distinguished symptomatic knees from normal controls. Congruence angles on stress radiography had a significant correlation with the functional scores obtained after a period of conservative treatment and a positive correlation with the frequency of patellar subluxation. When the quadriceps contracted, two patterns of patellar shift were observed. While the patella reduced into the trochlear groove in all normal knees and about 70% of the symptomatic knees, contraction of the quadriceps caused further subluxation of the patella in the remaining symptomatic knees. All the knee joints which showed this displacement failed to respond to conservative treatment and eventually required surgical treatment. Thus, this technique of stress radiography is a simple, cost-effective and useful method of evaluating patellar instability and predicting the prognosis.

Adolescent↗

[Analysis of epidermoid carcinomas using panoramic radiography and computerized tomography].

The purpose of this work was to compare radiographic findings, such as localization and extension of tumors toward the bone and soft tissues, in panoramic radiography and computed tomography (CT). Four radiologists assessed the radiographic findings of 48 patients with the histopathological diagnosis of squamous cell carcinoma in different sites of the maxillofacial region. Panoramic radiographs and computed tomographs were obtained at the University of Iowa Hospitals and Clinics, at FUNDECTO-USP and at the hospital of the University of São Paulo (USP). We observed a considerable limitation of the panoramic radiography in determining the localization and extension of tumors, since it revealed unclear delimitations. Regarding CT, better results were obtained: it was possible to observe the invasion of the tumor toward adjacent soft tissues, as well as the extension of bone destruction and the depth of the lesion, which were confirmed by surgical findings. We concluded that computed tomography demonstrated to be a sensitive radiographic technique for the detection of the involvement of bone and soft tissues, contributing for a more precise diagnosis, surgical planning and intervention. On the other hand, panoramic radiography was considered less sensitive and less efficient than CT, since it shows only unclear borders of the lesions and is not able to assess the involvement of soft tissues.

Carcinoma, Squamous Cell↗

Neonatal magnification radiography using standard-focus x-ray tubes.

Radiographic examination of the chests of premature newborn infants is complicated by the small size and poor object contrast of the structures to be evaluated. Magnification radiography can improve image quality significantly in this situation. Unfortunately, high-quality magnification radiography requires dedicated microfocus equipment that is not available in most neonatal intensive care units. The use of standard-focus x-ray tubes (up to 1 mm focal spot size) for moderate magnification radiography (1.5 times) by using the anode side of the x-ray field of the standard mobile x-ray unit is proposed. In addition to the cost advantage of using existing standard mobile x-ray equipment, the high tube current allows for short exposure times and long target-film distances. This reduces most motion unsharpness and allows for a large air gap that results in improved image contrast. Although focal spot size at the anode side of the field is smaller in only one dimension, the magnification radiographs are superior to those obtained using the central part of the x-ray beam and superior to standard contact radiographs using the same equipment. Improvement in image quality is due primarily to decreased noise and improved contrast in the magnified image.

Humans↗

Image-intensifier photofluorography and conventional chest radiography: comparison of diagnostic efficacy.

Photofluorography with a large image intensifier, which provides an image field of 40 x 40 cm, reduces both the radiation dose and the imaging costs in chest radiography as compared with the film-screen technique. The two techniques were evaluated in a clinical study of 135 patients with suspected chest abnormalities. Photofluorographs and film-screen chest radiographs were interpreted independently by three radiologists. The diagnoses were confirmed by CT, follow-up radiographs, and clinical records. Among the 135 patients, 75 had primary lung cancer, 39 had pulmonary nodules, 52 had hilar or mediastinal abnormalities, 17 had pleural fluid, and 45 had pneumonic or atelectatic changes. Twenty-three normal subjects were included. Differences in diagnostic accuracy, measured by sensitivity and specificity, were not statistically significant. A larger number of true-positive cases (65%) with peripheral lung nodules were found by photofluorography than by film-screen radiography (54%) (p less than .05). The results suggest that the diagnostic accuracy of chest images made by photofluorography is sufficient to warrant using it instead of the film-screen technique in routine chest radiography, especially to detect lung tumors and metastases.

Humans↗

Diagnosis of diseases of the trachea and main bronchi: chest radiography vs CT.

OBJECTIVE: The purpose of this study was to compare the sensitivities and diagnostic accuracies of chest radiography and CT in the assessment of diseases of the trachea and main bronchi in regard to detection, evaluation of focal vs diffuse disease, separation of benign from malignant disease, and accuracy of diagnosis. MATERIALS AND METHODS: The chest radiographs and CT scans of 35 patients with proved diseases of the trachea and main bronchi and five control subjects were randomly assessed by two independent observers in a blind study. The diagnoses included 25 malignant and 10 benign conditions. The malignant lesions included 24 primary tumors and one metastatic melanoma. The benign lesions included two benign tumors, two tracheal stenoses, one focal amyloidosis, one tracheomalacia, and four miscellaneous diffuse abnormalities. The observers were asked to determine if an abnormality was present, to classify it as focal or diffuse and as benign or malignant, and to list the three most likely diagnoses. Sensitivities were compared by using the McNemar test. RESULTS: The sensitivity of both observers in detecting disease on the chest radiograph was 66%. The sensitivity on the CT scan was 97% for the first observer and 91% for the second observer (p < .01). Both observers were able to correctly classify the detected abnormalities as either focal or diffuse in 91% of cases on the chest radiographs and 97% of cases on the CT scans. The abnormalities were correctly classified as either benign or malignant in 78% of cases by both observers on the chest radiographs and in 85% and 78% of cases on the CT scans by the first observer and the second observer, respectively. The correct diagnosis was included in the list of the three most likely diagnoses in 61% of cases by both observers after reviewing the radiographs and in 56% of cases by one observer and 63% of cases by the other observer after reviewing the CT scans. CONCLUSION: CT is superior to chest radiography in allowing detection of abnormalities of the major airways. Both CT and chest radiography are accurate for differentiating focal from diffuse disease, but neither technique is accurate for distinguishing benign from malignant disease or for establishing a specific diagnosis.

Adult↗

Preoperative examination of lung transplant candidates: value of chest CT compared with chest radiography.

OBJECTIVE: The purpose of our study was to determine the usefulness of CT in examining candidates for lung transplantation to detect cancer not visible on plain chest radiographs (a finding that would exclude a patient from transplantation) and to determine which lung is more severely diseased to aid in the decision of which side to transplant. MATERIALS AND METHODS: We reviewed the chest radiographs and CT scans of 190 transplant candidates during a 3-year period for findings suggestive of neoplasm, including lung nodules and atelectasis; we also reviewed the symmetry of disease. In the latter category, patients with primary pulmonary hypertension, Eisenmenger's complex (pulmonary vascular, not parenchymal, disease), and cystic fibrosis (for which bilateral transplantation is performed) were excluded. A total of 190 plain chest radiographs, 180 thin-section CT scans, and 31 standard CT scans were reviewed retrospectively. RESULTS: Plain chest radiographs revealed 20 noncalcified nodules; 13 were 8 mm or more in diameter, and 7 were less than 8 mm. CT scans revealed 66 noncalcified nodules; 37 were 8 mm or more in diameter, and 29 were less than 8 mm. Eight non-calcified nodules seen on plain chest radiographs were either absent on CT scans (and follow-up plain chest radiographs) or appeared calcified on CT scans. Solitary nodules in three patients proved to be bronchogenic carcinomas; two of these lesions were identified only on CT scans. CT prompted a change in the determination of which lung was more severely diseased from that made on the basis of plain radiography for 27 of 169 patients (16%) evaluated. Of the 45 patients who subsequently underwent transplantation, CT prompted a change in the determination of which side to transplant from that made on the basis of plain radiography for 4 patients (9%). CONCLUSION: CT provides additional information to supplement plain radiography in the examination of lung transplant candidates. This information can alter patient management, particularly when bronchogenic carcinoma is detected, and enable a better determination of which lung is more severely diseased to aid in the decision of which lung to transplant for single-lung transplantation.

Adolescent↗

Computed radiography of the chest in patients with paraesophageal varices: diagnostic accuracy and characteristic findings.

OBJECTIVE: The purpose of our study was to determine the diagnostic accuracy of computed radiography of the chest in the detection of paraesophageal varices and to describe the characteristic radiographic findings. SUBJECTS AND METHODS: From June 1995 through May 1997, in 100 consecutive patients, portal hypertension was diagnosed through both clinical and radiologic evidence. Computed radiographs of the chest and hepatic helical CT scans of these 100 patients with portal hypertension and 20 control subjects were analyzed by two chest radiologists and one abdominal radiologist, who were not aware of the results of the other study. RESULTS: On CT, paraesophageal varices were seen in 38 (38%) of 100 patients with portal hypertension. Overall, the sensitivity, specificity, and accuracy of chest computed radiography in the detection of paraesophageal varices were 53% (20/38), 90% (74/82), and 78% (94/120), respectively. In the patients with paraesophageal varices, splenomegaly (29/38, 76%), lateral displacement or obliteration of the inferior portion of the azygoesophageal interface (18/38, 47%), obliteration or nodularity of the inferior portion of the descending thoracic aorta interface (9/38, 24%), lateral displacement of the right inferior paraspinal interface (6/38, 16%), lateral displacement of the left inferior paraspinal interface (4/38, 11%), and varices in the left inferior pulmonary ligament (1/38, 3%) were seen on chest computed radiographs. Paraesophageal varices smaller than the diameter of the descending thoracic aorta (usually <2.5 cm) were not detected. CONCLUSION: Although chest computed radiography is only moderately sensitive for paraesophageal varices, the findings are characteristic when well developed, with a limited differential diagnosis. Splenomegaly, whether detected clinically or radiographically, eliminates most other diagnostic possibilities.

Adult↗