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Biomedical subjects

J L Doppman

Publications and source records attributed to J L Doppman.

At least 361 records · Page 20Linked to original sources

Proximal versus peripheral hepatic artery embolization experimental study in monkeys.

A case is described in which extensive embolization of the hepatic artery to reduce insulin production by a metastatic islet-cell tumor resulted in liver failure, intrahepatic abscesses, and death. The difference between proximal and peripheral hepatic artery obstruction was investigated in monkeys by embolizing hepatic arterial beds with Gelfoam and silicone. Gelfoam obstructed proximally, arterial collaterals developed rapidly, and liver function remained normal. Peripheral hepatic artery embolization with silicone produced liver infarction and severe functional abnormalities. Peripheral hepatic artery occlusion was more effective in preventing the development of collateral circulation but involved a significant risk of hepatic failure or abscess.

Adenoma, Islet Cell↗

Unusual radiographic features of Wegener's granulomatosis.

The classical radiologic manifestations of Wegener's granulomatosis are paranasal sinus disease and pulmonary nodules. A review of 31 clinicopathologically proven cases of Wegener's granulomatosis was undertaken to delineate some of the atypical radiologic presentations in this disorder. In 16 of the 31 patients a total of 18 atypical radiographic findings were demonstrated. These included lesions of the airways, parenchyma, pleura, and kidneys. We feel the "typical radiologic findings" of Wegener's granulomatosis should be expanded to include (1) endobronchial disease resulting in atelectasis of either a lobe or a complete lung, and (2) pleural disease with thickening or effusion which may be massive. While some of the rarer presentations are still not included, such a redefinition would cover more than 75% of our 31 cases.

Adolescent↗

Comparison of computed and conventional whole lung tomography in detecting pulmonary nodules: a prospective radiologic-pathologic study.

Whole lung computed tomography (CT) was performed on 25 patients with clinical diagnoses including osteogenic sarcoma. Ewing's sarcoma, rhabdomyosarcoma, fibrosarcoma, and melanoma in whom conventional tomography had revealed from one to four parenchymal nodules in one lung deemed resectable for either staging or treatment purposes. Thoracotomy was performed within 3 weeks after conventional and computed whole lung tomography. All palpable nodules were resected, measured at the time of surgery, mapped by anatomic segment, and submitted for individual histologic evaluation. CT defined more nodules than conventional tomography in 48% of cases. The additional nodules were usually pleural or subpleural and 3--6 mn in diameter. CT identified 78% of all resected nodules greater than 3 mm in diameter, compared to 59% using conventional tomography. CT was also of value in detecting bilateral nodules earlier than conventional tomography and in documenting small nodule growth on successive examination. However, 60% of the additional nodules defined by CT and resected proved to be benign granulomas and pleural-based nodes at thoracotomy.

Adolescent↗

Role of vascular proliferation on angiographic appearance and encapsulation of experimental traumatic and metastatic brain abscesses.

Experimental traumatic abscesses were produced in rhesus monkeys by intracerebral injection of nutrient agar contaminated with Staphylococcus epidermidis, and metastatic abscesses were induced by intracarotid embolization of silicone cylinders contaminated with Staphylococcus epidermidis. All monkeys underwent preoperative and serial postoperative carotid angiography. Traumatic abscesses produced early capsular blushes and progressive anterior cerebral artery displacements. Metastatic abscesses induced transient midline shifts but no capsular stains. Postmortem studies on the monkeys showed that mean capsular thickness and segmental wall vascularity of the traumatic and metastatic abscesses were significantly different (p less than 0.001), despite equal abscess ages and similar abscess volumes. In comparison to traumatic abscesses, metastatic abscesses demonstrated reduced inflammatory cell infiltration and retarded collagen formation around proliferating capsular vessels. Brain surrounding the metastatic abscesses demonstrated ischemic changes. The results suggest that 1) capsular blushes during cerebral angiography are secondary to vascular proliferation within the capsule and not to compression of surrounding brain, 2) vascular staining reflects capsular thickness, 3) capsular vascularity contributes to collagen formation, 4) encapsulation is dependent upon the integrity of surrounding brain, and 5) adjacent cerebral ischemia may impede inflammatory responses involved in capsule formation.

Animals↗

Ventilation-perfusion lung imaging and selective pulmonary angiography in dogs with experimental pulmonary embolism.

To determine the accuracy and limitations of Xe-133 ventilation and Tc-99m perfusion lung images (V-P images) in detecting pulmonary emboli (PE), these studies were performed in 23 dogs after experimental production of PE by a modified Wessler technique. Fourteen of the animals also underwent selective pulmonary angiography. Xenon-133 abnormalities were seen immediately after embolization in two of the 23 animals (8.7%). Perfusion images revealed the location of 83% of emboli that completely obstructed pulmonary vessels, but only 26% of those that partially obstructed flow. Defects were seen with 97% of emboli that completely occluded vessels larger than 2.0 mm in diameter, but in only 66% of those occluding smaller vessels. Oblique perfusion images provided the only evidence of the perfusion defect associated with five of 88 (5.7%) angiographically proven emboli. V-P imaging is a sensitive technique for detecting PE unless the emboli lodge in very small vessels or incompletely obstruct a vessel. Xenon-133 abnormalities occur infrequently following PE, and should not be a common cause for a false-negative V-P match in clinical practice.

Angiography↗

Reoperative parathyroid surgery for persistent hyperparathyroidism.

In a 2-year period 30 patients with persistent hyperparathyroidism following 59 prior unsuccessful procedures underwent reoperation. Preoperative arteriography was useful in planning the surgical approach in 56%, and retrospectively was correct in 63%. Selective venous catheterization gave localizing information in 83%, correctly predicting site or side in 60% of the total. Computerized axial tomography was helpful in identifying mediastinal glands before operation. Reoperation was successful in rendering the patient hypocalcemic or normocalcemic in 83%. Of the 11 patients (37%) who were rendered profoundly hypocalcemic, two were subsequently weaned from vitamin D and calcium support; seven have received either fresh or cryopreserved parathyroid autografts. Persistent hyperparathyroidism is a difficult surgical problem which we believe warrants aggressive localization attempts prior to operation. Autotransplantation with cryopreserved parathyroid tissue may be of value in the long-term management of the high incidence of postoperative hypocalcemia in this patient group.

Adenoma↗

Suspected pulmonary metastases: correlation of chest x-ray, whole lung tomograms, and operative findings.

Chest x-rays, whole lung tomograms, and operative findings were correlated in 152 patients with an extrathoracic malignancy who underwent 182 thoracotomies for the evaluation of pulmonary nodules. Among 25 patients with a normal chest x-ray but one or more pulmonary nodules demonstrated by whole lung tomography, 19 had metastatic disease documented at thoracotomy. Of 64 patients with unilateral nodules seen on conventional chest x-ray, 10 of 32 with sarcoma, 2 of 7 with melanoma, but only 2 of 25 with carcinoma had bilateral nodules demonstrated by tomography. At thoracotomy, 8 of 38 patients in whom a solitary nodule was present on both chest x-ray and on tomogram had multiple nodules. Similarly, 35 of 48 patients with more nodules seen on the tomograms than on the chest x-ray had even more extensive metastatic disease demonstrated by operation. Among patients who had resection of all metastatic pulmonary nodules, 50% of those with carcinoma and 32% of those with sarcoma who underwent resection of a solitary nodule approached that of patients with carcinoma. These findings suggest that whole lung tomograms contribute to the determination of the extent of pulmonary metastasis in patients with solid malignancies, even in the presence of a negative chest x-ray. The improved long term survival achieved by resection of these metastases may be partially attributed to this screening procedure.

Adult↗

Barium enema, proctosigmoidoscopy and upper gastrointestinal series in the preoperative evaluation of the cancer patient.

Charts of 566 patients admitted to the Surgery Branch, National Cancer Institute over a five year period were reviewed. Routine upper gastrointestinal series was performed in 453 patients; barium enemas in 490; and proctosigmoidoscopies in 342. Upper gastrointestinal series detected no metastases or second primary malignancies but delineated the extent of large intra-abdominal tumors. Barium enema and proctosigmoidoscopy together revealed three unsuspected primary colonic tumors (1.2% in patients over 50 years of age). Sigmoidoscopy and examination of the stool for occult blood would have detected the same patients. Barium enema may be limited to surgical cancer patients in whom the extent of local tumor invasion is to be defined and to older patients in whom colonic tumors are suspected. Neither UGIS nor barium enema appear to be of value as a routine preoperative screening test in surgical cancer patients.

Adolescent↗

The blood supply of mediastinal parathyroid adenomas.

Arteriography for parathyroid localization following unsuccessful neck surgery should include selective catheterization of the inferior thyroid and internal mammary arteries bilaterally. When the arterial supply to a mediastinal adenoma arises from the internal mammary artery, recovery from the neck may not be possible and an open mediastinal exploration (or embolization) should be considered.

Adenoma↗

Computed tomography for parathyroid localization.

Computed tomography (CT) of the neck and mediastinum was performed in 10 patients with primary hyperparathyroidism. Nine had undergone previous surgery and were considered localization problems. Of four subsequently proven cervical adenomas, only one unusually large 19-g adenoma was visualized by CT. However, of two subsequently proven anterior mediastinal adenomas, CT scanning was positive in both; a single posterior mediastinal adenoma was not demonstrated. Of the remaining three patients, one was not operated on; in two others no adenoma was found at surgery. CT scanning is recommended prior to neck surgery in all patients with primary hyperparathyroidism to identify adenomas in the anterior mediastinum.

Adenoma↗

Scleral calcifications in hyperparathyroidism: demonstration by computed tomography.

Scleral calcifications were demonstrated roentgenographically in two patients with known hyperparathyroidism and clinically normal eyes. In one of these patients, scleral calcification was evident both on plain films and with computed tomography (CT). In the second patient, a solitary plaque of calcified sclera was visible only by CT. Histopathologic examination of the eyes of a third hyperparathyroid patient who died during surgery demonstrated calcium plaques in the posterior sclera consistent with the CT appearance of the sclera in the other patients.

Adult↗

Angiographic abnormalities in partial Budd-Chiari syndrome.

Partial Budd-Chiari syndrome was produced in 8 monkeys by obstructing 2 or 3 lobar hepatic veins with a rapidly polymerizing plastic. Hepatic angiography done 1-3 months later revealed crowded tortuous arteries and a dense hepatogram in the lobe with venous occlusion. Unobstructed lobes were hypertrophied. Retrograde injection of persistently patent hepatic veins demonstrated a "spiderweb" collateral system. Retrograde venography to demonstrate this pathognomonic plexus is the procedure of choice when partial Budd-Chiari syndrome is suspected.

Animals↗