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A V Proto

Publications and source records attributed to A V Proto.

13 recordsLinked to original sources
PubMed1992

Conventional chest radiographs: anatomic understanding of newer observations.

Despite the advances in medical imaging modalities over the past several years, conventional chest radiography still remains the most commonly performed imaging examination. In this report, the author discusses four radiographic observations, all visible on the conventional chest radiograph, and the anatomic basis for each: (a) the normal apical opacity, produced by the subclavian artery and easily confused with parenchymal abnormality; (b) vascular reorientation with upper lobe volume loss, a characteristic divergent or parallel pattern helpful in recognizing upper lobe volume loss; (c) extrapleural fat, which simulates pleural plaques along the lateral chest walls and pleural thickening at the chest apices; and (d) mobility of the mediastinum, which contributes to incorrect mediastinal mass localization and creates soft-tissue bands in the retrosternal area.

Adipose Tissue↗
PubMed1989

The left paratracheal reflection.

The left paratracheal reflection, which is found medial to the left subclavian artery reflection, was sought in 302 normal posteroanterior (PA) chest radiographs, 93 conventional chest tomograms, and 113 thoracic computed tomographic (CT) scans. The left paratracheal reflection was visible on 31% of normal PA chest radiographs. Conventional tomography and CT showed that this finding is produced by contact of the lung with the mediastinum anterior to the left subclavian artery. The CT scans studied showed that the left paratracheal reflection actually represents contact of the lung with left paratracheal mediastinal fat 94% of the time, with the proximal 1-2 cm of the lateral wall of the left common carotid artery 5% of the time, and with the left tracheal wall 1% of the time. A variety of entities may alter the left paratracheal reflection.

Adult↗
PubMed1978

350 kVp chest radiography: review and comparison with 120 kVp.

High kilovoltage radiography had its beginning with super-voltage technique and is presently accomplished with the 350 KV chest x-ray system. The physical reasons to explain the improved visibility with this technique are: (1) absorption coefficients of bone and soft tissue, (2) more uniform bone visibility, (3) x-ray spectrum, (4) visual responses, and (5) depth resolution. In this study, 350 kV and 120 kV chest x-ray techniques were compared by evaluating 15 parameters. Based on our data and the results of previous large clinical studies, a list of disadvantages and advantages is offered. The entrance dose for an average 350 kV posteroanterior chest radiograph is 8 mR, or about one-third that with 90 kV technique.

Absorption↗
PubMed1977

Computed tomography of the mediastinum. Normal anatomy and indications for the use of CT.

Correlative CT studies of a cadaver and a statistical analysis of all thoracic scans performed in the first year of operation of a delta-Scan 50 were undertaken in order to better understand normal mediastinal anatomy as displayed by computed tomography. Several levels are illustrated, and the results of the analysis are reported. The authors propose a list of indications for which CT of the mediastinum seems to be helpful.

Female↗
PubMed1977

Air in the esophagus: a frequent radiographic finding.

While the radiologic literature discusses the presence of air in the esophagus on chest radiographs, this has almost always been reported as a finding associated with other radiologic abnormalities. In a retrospective study, esophageal air was noted on 36% of normal posteroanterior chest radiographs. The radiologic anatomy of the esophagus and the typical locations of air within it are discussed.

Air↗
PubMed1977

Radiologic analysis of the mediastinum utilizing computed tomography.

An attempt has been made to demonstrate the capacity of computed tomography to display mediastinal anatomy. A further attempt has been made to develop a list of indications for the performance of this study in patients with known or suspected mediastinal disease. It should be recognized that the statements made are based on a relatively small patient sample. Undoubtedly, future experience will add to and delete from the indications presented here.

Aorta, Thoracic↗
PubMed1976

Visualization of differences in soft-tissue densities. The liver in ascites.

The lateral liver border was demonstrated on the plain radiograph in 54 of 100 proved cases of ascites. The etiology of ascites, the density of the fluid, and the total protein content were similar whether the border was visualized or not. Tomography of the right upper quadrant indicated that the lateral liver margin is visualized in ascites as a result of contact between the liver and the surrounding fluid. Radiography of autopsied livers submerged in fluid demonstrated distinguishable differences in object density, and photodensitometry of the plain radiographs revealed a difference in blackness where the fluid and liver made contact. Comparison of mean liver density and mean ascitic fluid density showed a difference of 5%. These findings indicate that differences in soft-tissue densities (excluding fat) can be distinguished on the plain radiograph.

Ascites↗
PubMed1976

Mach bands and density perception.

Perception of a roentgen image is greatly influenced by the production of Mach bands by the retinal neural networks. The mechanism of their production and contributing factors such as lateral inhibition, projection, contour, film density, object density, and background are discussed. Although Mach bands often facilitate perception of roentgen density, misinterpretation of their significance may lead to errors in diagnosis.

Animals↗
PubMed1976

A new concept of ascitic fluid distribution.

Of 26 patients with ascites examined by B-mode ultrasonography, 14 had scans appropriate for evaluating the presence of fluid within the abdominal cavity. These studies demonstrate localization of fluid anteriorly around the tip of the liver and emphasize the importance of such factors as density relationships and the "pliability" of the anterior abdominal wall in the distribution of ascitic fluid. A reveiw of the literature is presented.

Ascites↗
PubMed1975

Duodenotomy defect.

Radiographic changes in the duodenum after duodenotomy are discussed. Two types are noted. One is a polypoid mass, the other is a convex deformity at the lateral wall of the descending duodenum. The radiographic findings are explained by the surgical technique used for duodenotomy.

Adult↗