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Biomedical subjects

J L Doppman

Publications and source records attributed to J L Doppman.

At least 289 records · Page 16Linked to original sources
PubMed1982

Biodistribution study of Ethiodized Oil Emulsion 13 for computed tomography of the liver and spleen.

Biodistribution studies were conducted with a new intravenous lipoid contrast material currently undergoing clinical trials in four hospitals. The contrast material selectively opacifies the liver and spleen for computed tomographic examination. The experiments were performed on rats with 125I-labeled ethiodized oil emulsion. The study showed that the liver accumulates nearly 80% of the injected iodine within 15 min of the injection and retains a high concentration over 3 h. The second highest concentration was found in the spleen. More than 99% of the iodine is eliminated from the liver and spleen within 48 h, primarily through the kidneys.

Animals↗
PubMed1982

Failure to detect a 1.5 centimeter lung nodule by chest computed tomography.

Although computed tomography (CT) of the chest is the most sensitive modality for the detection of pulmonary nodules, false negatives occur. A case is presented in which a 1.5 cm nodule in the lung confirmed by surgery and linear tomography was not detected by using a state-of-the-art CT scanner. The reason for this failure is movement of the nodule between scans due to variations in respiratory excursion. This effect can be somewhat reduced by scanning at end tidal volumes with thick overlapping or contiguous scans.

Adolescent↗
PubMed1982

Failure to ablate the adrenal gland by injection of contrast material.

Five attempts were made in 4 patients to infarct an adrenal gland containing an aldosterone-producing tumor, using vigorous retrograde injections of contrast material into the adrenal vein. Although a modest amount of tumor staining was attained in 3 patients, no clinical or laboratory changes were seen. Contrast extravasation appears to be a transient and benign complication. Adrenal vein thrombosis is probably responsible for the reported adrenal infarctions but can be prevented by systemic anticoagulation. The authors conclude that adrenal venography is a safe procedure whose potential risks are far outweighed by the decreased surgical complications when a functional adrenal tumor is accurately located preoperatively.

Adenoma↗
PubMed1982

Localization of functional adrenal tumors by computed tomography and venous sampling.

Fifty-eight patients with functional lesions of the adrenal gland underwent radiographic evaluation. Twenty-eight patients had primary aldosteronism (Conn syndrome), 20 had Cushing syndrome, and 10 had pheochromocytoma. Computed tomography (CT) correctly identified adrenal tumors in 11 (61%) of 18 patients with aldosteronomas, 6 of 6 patients with benign cortisol-producing adrenal tumors, and 5 (83%) of 6 patients with pheochromocytomas. No false-positive diagnoses were encountered among patients with adrenal adenomas. Bilateral adrenal hyperplasia appeared on CT scans as normal or prominent adrenal glands with a normal configuration; however, CT was not able to exclude the presence of small adenomas. Adrenal venous sampling was correct in each case, and reliably distinguished adrenal tumors from hyperplasia. Recurrent pheochromocytomas were the most difficult to localize on CT due to the surgical changes in the region of the adrenals and the frequent extra-adrenal locations.

Adenoma↗
PubMed1982

Radiographic findings in recurrent parathyroid carcinoma.

Seven cases of recurrent parathyroid carcinoma were reviewed. Subperiosteal resorption was seen in 6, pulmonary nodules in 4, renal calculi in 5, brown tumors in 5, and pancreatic calcification in 1. Angiography was performed in 5 patients, showing 1 definite and 2 probable cervical recurrences, 1 mediastinal lesion, and 1 case of possible bone metastases. Venous sampling for parathyroid hormone was carried out in 4 patients and suggested residual disease in 2; in addition, there were 1 false and 1 true negative. CT was performed in 4 patients and was useful in delineating metastatic pulmonary nodules, cervical recurrence, and hepatic metastases. The radiographic approach to recurrent parathyroid carcinoma and the use of CT and angiography are discussed.

Adult↗
PubMed1982

The risk of hepatic artery embolization in the presence of obstructive jaundice.

Rhesus and cynomolgus monkeys were used as experimental subjects to determine the extend to which the presence of biliary obstruction increases the risk of hepatic necrosis following hepatic artery embolization. It was found that peripheral hepatic artery embolization without biliary obstruction resulted in acute hepatic swelling and dysfunction and chronic focal infarction with bile cyst formation. However, massive hepatic necrosis and bile lakes were not seen. Distal common bile duct obstruction unaccompanied by arterial occlusion did not seriously damage the liver, although it was found that distal common duct obstruction in monkeys is not strictly comparable to distal common duct obstruction in humans. When peripheral hepatic artery embolization was performed following ligation of the right or left hepatic ducts at the point of their emergence from the porta hepatis, total infarction of the obstructed segment occurred and a massive bile lake formed. The pathophysiologic explanation is probably the decreased portal venous inflow that accompanies biliary obstruction; hepatic artery inflow reciprocally increases and the liver become critically dependent upon an intact arterial system. Clinical evidence suggests that a liver with a recently decompressed biliary tree may also be more susceptible to infarction and abscess formation following hepatic artery ligation or embolization.

Animals↗
PubMed1982

The radiographic follow-up of patients with Ewing sarcoma: a demonstration of a general method.

An analysis of the patterns of detectable tumor recurrence using the concepts of hazard rate, predictive value, and cumulative probability was undertaken to assess the appearance of metastases in Ewing sarcoma. This study comprises 107 patients who were seen between 1964 and 1977. The distribution of the sites of metastases indicates that repeated examinations of both lungs and bones are necessary for the effective surveillance of both truncal and extremity primary lesions. The hazard rates for metastases suggest that these serial examinations should be concentrated early in the follow-up period for truncal primaries and more uniformly distributed for extremity primaries. The method used is general and is applicable to any disease for which the surveillance for recurrence or a complication is of major concern. The results of the analysis may be used in the selection and scheduling of follow-up examinations for patients with Ewing sarcoma, and in advising the patient of the prognosis for continued remission.

Bone Neoplasms↗
PubMed1982

Interventional radiology polymer update: acrylic.

An overview of intravascular interventional embolic materials is presented. The physicochemical and biological properties of the monomer isobutyl 2-cyanoacrylate are discussed with specific details regarding therapeutic applications.

Bucrylate↗
PubMed1982

Computed tomography of the liver and spleen with intravenous lipoid contrast material: review of 60 examinations.

In 60 computed tomographic examinations of the liver and spleen in 55 patients, a new intravenous lipoid contrast material, Ethiodized Oil Emulsion 13, was used. This organ-specific contrast material, retained by the reticuloendothelial cells of the liver and spleen, caused marked increase in the attenuation of the liver and spleen, but did not appreciably change the attenuation of the tumor involving these organs, thereby significantly increasing the density differential between normal and abnormal tissue. Toxicity was considered to be well within tolerable limits with the most frequently noted untoward side effects of chills, fever, headaches, and foul metallic taste. Ethiodized Oil Emulsion 13 holds the promise to become a valuable clinical tool by which hepatic and splenic imaging may be significantly improved and lesions less than 1 cm in diameter demonstrated in the liver and spleen.

Adult↗
PubMed1982

Assessment of techniques for preoperative parathyroid gland localization in patients undergoing reoperation for hyperparathyroidism.

Persistent and recurrent hyperparathyroidism after previous unsuccessful surgery is a major problem for the patient and the physician. We have prospectively evaluated the ability of cine-esophagography, computed tomography, selective venous sampling for parathyroid hormone, and selective arteriography to preoperatively detect parathyroid tissue in 75 patients undergoing reoperation. The invasive studies were routinely and safely applied to all patients in an effort to determine their value. In 55% of studies performed, preoperative localization by selective venous sampling was consistent with the subsequent operative findings. Selective arteriography correctly localized abnormal parathyroid tissue in 49% of studies performed but was more specific than selective venous sampling. Cine-esophagography was not of help in localization but did demonstrate abnormalities of swallowing attributed to prior surgery. Computed tomography correctly localized 11% of patients studied.

Adolescent↗
PubMed1981

Computed tomography in constrictive pericardial disease.

Thirteen patients with pericardial abnormalities and a question of constrictive hemodynamics underwent contrast enhanced cardiac computed tomography (CT). Those with clinical and catheterization evidence of restricted cardiac filling demonstrated three CT signs: a dilated IVC, a deformed ventricular contour, and an angulated interventricular septum. Patients with pericardial fluid, thickening, or calcification but without evidence of constriction showed none of these signs. Cardiac CT also defined sites of particular constriction for subsequent resection.

Adult↗
PubMed1981

The visualized interventricular septum on cardiac computed tomography: a clue to the presence of severe anemia.

Severe anemia (10 g hemoglobin or less) will provide sufficient negative contrast on computed tomography (CT) to visualize the intracardiac chambers or lumina of large blood vessels. In the presence of secondary hemochromatosis, imaging of the interventricular septum can be due to excess cardiac iron (hemochromatotic cardiomyopathy) or the underlying transfusion-dependent anemia. Five percent glucose/water may be a satisfactory negative contrast agent for cardiac CT.

Anemia↗
PubMed1981

Use of intravenous liposoluble contrast material for the examination of the liver and spleen in lymphoma.

An experimental contrast material has been developed that, after intravenous injection, selectively opacifies the spleen and liver on computed tomography (CT). The contrast material contains iodinated ester of poppy seed oil in an emulsified form. Clinical trials were recently initiated to test the value of this contrast agent in Hodgkin's and non-Hodgkin's lymphomas. We present here two of our initial patients in whom we found lesions in the spleen or liver following the infusion of the experimental contrast material that were not visualized on the precontrast and urographic contrast material enhanced CT scans.

Adult↗
PubMed1981

The role of pancreatic venous sampling in the localization of occult insulinomas.

The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production.

Adenoma, Islet Cell↗
PubMed1981

Failure of ablation of a mediastinal parathyroid adenoma by repeated contrast staining.

In a patient with primary hyperparathyroidism an attempt was made to ablate a middle mediastinal parathyroid gland by forceful staining with radiographic contrast material. The gland was stained on two separate occasions, two weeks apart. Both times the serum calcium level temporarily fell to the normal range but reverted to abnormal levels. The patient ultimately required surgery for correction of hypercalcemia. The mechanism of staining and possible reasons for failure as well as potential complications are discussed.

Adenoma↗
PubMed1981

The detection of mediastinal parathyroid glands by computed tomography, selective arteriography, and venous sampling: an analysis of 17 cases.

Computed tomography (CT) scans were reviewed in 19 cases of proved mediastinal parathyroid glands. Glands were detected in five of 17 cases (29%) with adequate scans; four of six (67%) anterior mediastinal glands larger than 2 cm were visible. The smallest lesion demonstrated by CT ws 1.6 cm. In the same series, selective arteriography was positive in 10 of 15 cases (67%), with the smallest lesion measuring 0.5 cm. Venous sampling was performed in 15 patients, and a thymic sample obtained in 10; a twofold step-up of parathyroid hormone in thymic veins was noted in eight of 15 cases (53%), but was not localizing, as samples in other veins were elevated in all but one case. Angiography appears more sensitive than second-generation CT for detecting mediastinal glands. However, CT is very useful in patients with previous failed explorations. Scanning must include contiguous sections extending several centimeters below the carina, in order to encompass low-lying mediastinal glands.

Adenoma↗
PubMed1981

Parathyroid imaging after intraarterial injections of [75Se]selenomethionine.

Thirteen patients with persistent hyperparathyroidism after unsuccessful neck surgery were given up to 250 microCi [75Se]selenomethionine intraarterially during parathyroid arteriography, gamma-Camera images of the neck and mediastinum localized abnormal parathyroids in four of five patients receiving complete injections, despite very small glands or unsuccessful arteriograms in some of the patients. Correctly localizing images were obtained in three patients receiving incomplete injections. However, images in five of eight of the remaining patients receiving incomplete injections showed areas of false positive uptake, and there was no way preoperatively to distinguish these from the true positive studies. We conclude that intraarterial injection of radioselenomethionine is a simple supplementary procedure in patients undergoing arteriography that may, with proper technique, be useful in identifying small foci of abnormal parathyroid tissue.

Humans↗