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S T Cochran

Publications and source records attributed to S T Cochran.

51 records · Page 3Linked to original sources
PubMed1980

Cytogenetic effects of contrast material in patients undergoing excretory urography.

Acentric chromosome fragments produced in cells by irradiation or other agents give rise to micronuclei in daughter cells. The micronuclei can be counted readily in large numbers of cells which provides a sensitive measure of chromosome aberrations. Previous studies have shown that the presence of contrast material enhances the radiation-induced yield of micronuclei in vitro. This may be due to the dose enhancement effect and the chemical action of contrast media or their derivatives. Micronuclei were scored in peripheral blood lymphocytes obtained from 26 patients before and after excretory urography (ExU). The results show a consistent and significant increase in the counts after ExU amounting to about one third of the counts blood samples before the examination. We have also measured radiation exposures in this group and estimated an average exposure to the circulating lymphocytes of about 0.2R (0.52 X 10(-4) C/kg). We conclude that the contrast medium contributed significantly to the increase in micronuclei.

Adult↗
PubMed1980

Radiographic and microscopic findings in multiple ureteral diverticula.

Ten cases of multiple ureteral diverticula are presented. Microscopic correlation was available in 5. Associated findings included urinary stones, obstruction, infection, and transitional-cell carcinoma. Such diverticula are one manifestation of epithelial hyperplasia, more commonly seen as ureteritis cystica.

Aged↗
PubMed1980

The ultrasonographic diagnosis of cholecystitis and cholelithiasis in children.

Cholecystitis and cholelithiasis should be considered in the differential diagnosis of abdominal pain in children. Ultrasonography should be a primary screening test because it allows rapid evaluation of the gallbladder and identifies other possible causes of the symptomatology. The presence of a thickened gallbladder wall, cholelithiasis, or a nonvisualized gallbladder indicates gallbladder disease. Since acalculous cholecystitis is more common in children than it is in adults, it is particularly important to examine the gallbladder wall carefully for evidence of thickening.

Adolescent↗
PubMed1979

Nephromegaly in hyperalimentation.

Nephromegaly associated with hyperalimentation and its effect on renal function were studied. Renal size was determined in 44 patients receiving total parenteral nutrition (TPN). Of 26 patients in whom kidney size could be determined before and during TPN, all but one had normal-size kidneys before TPN. Six had no increase in renal size, and kidneys increased in size in 20. One or both kidneys became abnormally large in 9 patients. There was no detectable change in renal function and kidneys decreased in size upon discontinuation of hyperalimentation. Abnormal renal size bore no relation with weight gain or liver function tests.

Adolescent↗
PubMed1979

Augmentation enterocystoplasty.

The anatomy and radiographic appearance of five types of augmentation enterocystoplasty (ileocystoplasty, cecocystoplasty, ileocecocystoplasty, sigmoidocystoplasty, and enterourethroplasty) are described. Retrograde cystrography is the procedure of choice for optimal visualization of an augmented bladder and most complications. Excretory urography is useful for following concurrent upper tract disease and ureteral stenosis. Critical factors in a optimal examination are maximal filling of the bladder and radiographs in multiple projections.

Cecum↗
PubMed1978

Complete obstruction of the gastric antrum in children following acid ingestion.

We report on two children who experienced delayed complete obstruction of the gastric antrum following concentrated acid ingestion. Both patients required initial tube gastrostomy and subsequent antrectomy with intestinal reconstruction. Unlike the more common alkaline corrosives, ingested acids tend to spare the esophagus and gastric fundus. While gastric perforation and vascular collapse may occur immediately following overwhelming acid ingestion, the more common course is chronic gastric antral inflammation with subsequent fibrosis and, in some cases, complete stricture. Delayed surgical reconstruction is recommended to permit the acute inflammation and edema to subside.

Adolescent↗
PubMed1977

Obstruction of the airways by the heart and pulmonary vessels in infants.

It is well known that certain cardiovascular abnormalities, frequently compress the airways in infants [1]. Two additional cardiac mechanisms of airway obstruction are described in this paper: progressive compression of the bronchial tree by left sided cardiac enlargement and infantile cardiac asthma due to compression of the small airways by pulmonary venous congestion. Functional and reversible collapse of the trachea is a frequent finding in cardiac asthma. Infants with these entities often appear to have primary pulmonary disease when in fact the underlying cause of their distress is cardiac in origin.

Airway Obstruction↗
PubMedDate not supplied

Renocolic fistulas: complementary roles of computed tomography and direct pyelography.

Three patients with renocolic fistulas are presented. Antegrade or retrograde pyelography showed the fistula in one patient but was unsuccessful in two others. CT demonstrated perinephric inflammation extending to the colon, complex air-fluid collections within the kidney, or extension of renal contrast into the colon. CT and direct pyelography complement each other for the diagnosis of renocolic fistulas.

Aged↗
PubMedDate not supplied

Cytogenetic effects of contrast material: diatrizoate versus iothalamate.

Acentric chromosome fragments produced in cells by irradiation or other agents give rise to micronuclei in daughter cells. The micronuclei can be readily counted in large numbers of cells thereby providing a sensitive measure of chromosome aberrations. Previous studies have shown a consistent elevation of micronuclei count following the use of diatrizoate contrast materials. This study was undertaken to compare the micronuclei counts of patients receiving sodium iothalamate with those receiving sodium diatrizoate. Our results indicate that sodium diatrizoate produced significantly greater cytogenetic damage than the sodium iothalamate agents.

Adult↗
PubMedDate not supplied

Nephrotoxicity of epinephrine-assisted venography.

A retrospective study was performed to determined the nephrotoxicity of epinephrine-assisted venography (EAV). The results showed an increase in the serum level of creatinine (sCr) up to five days after EAV in 67% of patients, in comparison with 16% in patients who had other types of renal angiography. Microscopic examination of renal specimens from patients who had undergone EAV showed vacuolization of the epithelial cells of the proximal tubules. Risk factors for acute renal failure that have been described in the literature were not statistically significant in this study. These findings suggest that EAV is a more nephrotoxic procedure than renal angiography without EAV.

Adolescent↗
PubMedDate not supplied

Advantage of underweight.

Exposure measurements made during a diagnostic radiological study revealed that heavy set patients pay a higher price in absorbed dose than lighter people.

Body Weight↗
PubMedDate not supplied

Diagnostic effects of edge sharpening filtration and magnification on digitally subtracted renal images.

The improved appearance of digital radiographs filtered to improve local contrast and sharpen edges has not increased acceptance of these images by radiologists. Furthermore, many radiologists assert that correct diagnosis is not improved with these filtered images. This study was designed to test this assertion for digital subtraction angiograms (DSA) of renal images. Four experiments are described. First, phantom studies identified filters and their parameters thought likely to be acceptable and useful in diagnosing renal images formed by DSA. Second, these filters and parameters were then tested on medical images to assess their acceptance by radiologists. Third, display modes of windowing, positive/negative presentation, and magnification were varied for filtered and unfiltered images to assess preferences of radiologists. Fourth, filtered and unfiltered magnified images were used to test improved diagnosis. In the final experiment, 148 images from 33 renal studies (15 normal, 18 abnormal) were magnified, gray level windowed, and filtered. Diagnosis was not improved by the two edge sharpening filters tested.

Angiography↗
PubMedDate not supplied

Medical pattern recognition pitfalls in a clinical setting: renal cell carcinoma survival prediction.

Three studies to predict renal cell carcinoma patient survival from tumor textures found in digitized early venous phase arteriograms were successful individually. However, when the three methods were compared, they were not consistent and no single method was clinically useful. The first study predicted 5 yr survival of 37 patients with 87% accuracy. The second study added 29 patients to the data base; the poor survival of the 21 patients who died within 5 yr of diagnosis was predicted with 80.9% accuracy. When 27 of these cases were redigitized with a laser scanner, average survival prediction accuracy was 78%. In these studies, digitization hardware, radiographic technique, normalization methods, window selection, and contrast medium distribution all contributed to differences in the statistics separating poor from good patient survival.

Angiography↗
PubMedDate not supplied

Complications of peritoneal dialysis: evaluation with CT peritoneography.

Computed tomographic (CT) peritoneography involves CT of the abdomen and pelvis after administration of a mixture of contrast material and dialysate. CT peritoneography can demonstrate a variety of complications of continuous ambulatory peritoneal dialysis. In patients with symptoms of peritonitis, CT peritoneography is better than conventional CT in demonstrating loculated fluid collections and indicates adhesions by means of uneven distribution of the contrast material-dialysate mixture. In patients with edema or abdominal bulging, CT peritoneography reliably shows the site of dialysate leakage and allows differentiation of a leak from a hernia. In patients with problems of fluid return, catheter malposition and its effect on dialysate distribution can be determined with CT peritoneography. In patients with poor ultrafiltration, demonstration of restricted space in the pelvis or poor distribution of fluid with CT peritoneography suggests adhesions. CT peritoneography also provides anatomic information for referring physicians that may determine whether treatment is medical or surgical.

Adult↗