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Biomedical subjects

J L Doppman

Publications and source records attributed to J L Doppman.

At least 271 records · Page 15Linked to original sources
PubMed1983

Experimental evaluation of five liver-spleen specific CT contrast agents.

We tested five experimental liver-spleen specific computed tomography (CT) contrast agents, all of which are aqueous emulsions of iodinated vegetable oils. These compounds were compared with ethiodized oil emulsion 13 (EOE-13) and with a 5% dextrose in water control. We evaluated three animal/dose level models with both histology and CT to determine the best screening method for compounds of this type. We compared a rat/high dose model, a rat/medium dose model, and a rabbit/low dose model; the best discrimination was seen with the rabbit/low dose model. Histology of liver, spleen, and lung did not correlate with the attenuation values obtained from CT. We conclude that use of CT and a rabbit/low dose model is superior for screening compounds of this type. Of the compounds tested, only one, an emulsion of ethyl monoiodostearate (compound 208E), approached the effectiveness of EOE-13.

Animals↗
PubMed1983

Work in progress: abnormal parathyroid glands. Comparison of nonselective arterial digital arteriography, selective parathyroid arteriography, and venous digital arteriography as methods of detection.

Nonselective arterial digital arteriography (NSADA), selective parathyroid arteriography (SPA), and venous digital arteriography (VDA) were compared as methods of detecting parathyroid enlargement in 14 patients with primary hyperparathyroidism undergoing preoperative localization following unsuccessful neck surgery. All 14 had SPA and NSADA, consisting of contrast injections into the ascending aorta, innominate artery, and left subclavian artery; 7 also had VDA. Surgery was performed in 9 patients, and 2 additional glands were confirmed by fine-needle aspiration and venous sampling. Parathyroid glands could not be located in 3 patients, who were not re-explored. SPA demonstrated 11/13 abnormal glands (85%). NSADA detected 7/13 (54%), and there were 2 false positives. VDA showed 5/6 glands detected by NSADA (83%); the seventh patient did not have VDA. The overall quality of VDA was inferior to NSADA. Although NSADA and VDA are less sensitive than SPA, they are safer and easier to perform and should be the initial vascular screening procedures following unsuccessful parathyroid surgery.

Adult↗
PubMed1983

Aspiration of enlarged parathyroid glands for parathyroid hormone assay.

Enlarged parathyroid glands were percutaneously aspirated under computed tomographic (CT) control in 7 patients, and levels of parathyroid hormone (PTH) and human thyroglobulin (HTg) were measured. All 7 patients had high levels of PTH in at least 1 specimen. It is concluded that the measurement of high concentrations of PTH in the aspirate from a cervical or mediastinal mass, with CT documentation of needle position, provides absolute localization of parathyroid masses.

Adenoma↗
PubMed1983

Hemobilia: computed tomographic diagnosis.

A case of postbiopsy hemobilia is presented in which computed tomographic (CT) scanning showed blood within the gallbladder appearing as high-density material measuring 67-91 HU. Residual clots were seen by CT and ultrasound 8 days after the acute episode. These findings were confirmed by serial CT scans in two monkeys in whom blood was experimentally injected into the gallbladder. When the cystic duct is patent, the diagnosis of hemobilia may be excluded if bile of normal density (0-20 HU) is demonstrated by CT scanning. However, when homogeneous or inhomogeneous material of high attenuation (50+ HU) is present in the gallbladder on CT scanning, the diagnosis of hemobilia is strongly suggested if other causes such as stone or contrast material have been eliminated. CT may show residual blood for days after the acute episode.

Adult↗
PubMed1983

Embolization of arteriovenous malformations by direct percutaneous puncture.

Permanent control of arteriovenous malformations requires obliteration of the intrinsic vasculature of the lesion with a nonresorbable occlusive material. When tortuous feeding arteries prevent successful catheter positioning, it may be possible to percutaneously puncture the malformation with a Chiba needle for direct embolization with cyanoacrylate. Three illustrative cases are presented. In each, previous surgical ligation of feeding vessels was ineffective and embolization by catheter was not possible when the fistula recurred. Direct puncture of one or more feeding vessels with occlusion by cyanoacrylate controlled these fistulas, two of which were massive. No complications occurred.

Adult↗
PubMed1983

Detection of hepatic metastases: comparison of EOE-13 computed tomography and scintigraphy.

Accurate detection of hepatic metastases is necessary to properly stage and follow many malignancies. Nineteen patients underwent computed tomographic (CT) examination with ethiodized oil emulsion 13 (EOE-CT) and liver scintigraphy within 1 month of an exploratory laparotomy. The sensitivity, specificity, and accuracy of these two imaging procedures were evaluated statistically. No differences were seen when the patients were scored as positive or negative for metastases. However, in a lesion-by-lesion analysis of 58 hepatic lesions, the sensitivity of EOE-CT was 69.0% and the sensitivity of scintigraphy was 32.8% (p less than 0.001). All lesions detected scintigraphy were also detected by EOE-CT. EOE-CT had a size threshold of 1.0-1.5 cm, while liver scintigraphy had a threshold of 2.5-3.0 cm. EOE-CT is a more sensitive examination for detection of small hepatic metastases than liver scintigraphy.

Contrast Media↗
PubMed1983

Successful treatment of a group of spinal cord arteriovenous malformations by interruption of dural fistula.

As demonstrated by selective spinal cord arteriography, over 80% of spinal cord arteriovenous malformations (AVM's) occupy a predominantly extramedullary position. Current therapy frequently requires surgical stripping of the long dorsal intradural vessel(s) from the underlying spinal cord over many cord segments. The authors report six patients with a dural arteriovenous fistula fed by a cluster of abnormal epidural arteries. These vessels, which surrounded and were embedded into the dural covering of a thoracic nerve root, drained into a long sinuous intrathecal paramedullary vein(s). The angiographic and surgical appearance of the intradural component of these lesions was identical to that of lesions previously classified as Type I AVM's of the spinal cord. All patients had symptoms and signs of myelopathy. In five patients, surgery was limited to coagulation and excision of the extradural vessels and division of the intradural arterialized vein. Progressive improvement began within days following surgery. No residual abnormality was demonstrated by postoperative selective spinal cord arteriography, which was performed in all five patients. The findings support those of Kendall and Logue, that surgery restricted to elimination of the arteriovenous fistula at the intervertebral foramen is curative, and that more extensive surgery is unnecessary for this subgroup of AVM's of the spinal cord. These lesions comprise a sizable percent of all spinal AVM's. Resolution of myelopathy in these patients supports the hypothesis that venous hypertension causes chronic progressive myelopathy.

Adult↗
PubMed1983

Zollinger-Ellison syndrome: current concepts and management.

Over the last few years the approach to managing patients with the Zollinger-Ellison syndrome has changed dramatically. The establishment of gastrin hypersecretion by a non-beta islet cell tumor as responsible for the gastric acid hypersecretion, and the subsequent development and widespread availability of gastrin radioimmunoassays have changed the criteria generally used for diagnosis and have led to an increased understanding of syndromes that can mimic Zollinger-Ellison syndrome. With the availability of histamine H2-receptor antagonists, gastric acid hypersecretion can be controlled medically in almost all patients with Zollinger-Ellison syndrome, obviating routine total gastrectomy. With the reduced mortality from gastric acid hypersecretion, increased attention is being focused on the natural history of the gastrinoma. Newer methods of localizing tumors are being investigated with a view to surgical removal of the gastrinoma, and the importance of developing an affective chemotherapeutic regimen is becoming increasingly apparent.

Adolescent↗
PubMed1983

Long-term ocular effects of osmotic modification of the blood-brain barrier in monkeys. I. Clinical examinations; aqueous ascorbate and protein.

The blood-aqueous humor barrier in adult rhesus monkeys was opened by intracarotid infusion of a 25% mannitol solution. Each monkey had one to four infusions into the same artery, with at least one week between subsequent procedures. The monkeys were observed clinically for 3 to 212 days. Within an hour pigmented cells and protein accumulated in the aqueous humor of the mannitol-treated eyes. Hypotony developed within a day. Aqueous flare and cells cleared within 2 weeks. Hypotony resolved in 8 to 12 weeks. More than one half of the monkeys had transient anisocoria. In some, the pupil in the treated eye was miotic; in others it was dilated. Direct and consensual pupil responses to light remained intact in untreated eyes and in treated eyes with mydriasis. About one fourth of the monkeys developed edema of the ipsilateral optic disk. This correlated with hypotony. No monkey developed cataract, corneal opacity, or vitreous or retinal change. The aqueous protein concentration was slightly above normal a month or more after the carotid infusions, but was considerably less than plasma protein concentration. Posterior and anterior aqueous ascorbate concentrations in treated eyes were slightly below normal, but far greater than plasma concentration, indicating that ascorbate active transport by the ciliary epithelium was essentially intact despite the widespread, permanent structural alteration that had been caused by the mannitol treatment.

Animals↗
PubMed1983

Long-term follow-up of patients with hyperparathyroidism treated by transcatheter staining with contrast agent.

Primary hyperparathyroidism is generally treated by primary neck exploration. Particularly in patients with hyperparathyroidism caused by adenoma, cervical exploration is generally curative, and extensive preoperative localization studies are unnecessary. If, after thorough primary cervical exploration, no adenoma is identified or at least four parathyroid glands are not confirmed and the patient's hypercalcemia persists, radiologic localization studies are indicated prior to a repeat operation. Persistent hypercalcemia in defined as the failure of calcium levels to return to normal soon after parathyroid exploration; recurrent hyperparathyroidism is defined as hypercalcemia that follows 6 months of low or normal serum calcium levels. Persistent or recurrent hypercalcemia not controlled by a primary cervical exploration may be due to an ectopic parathyroid adenoma, either outside the usual anatomic sites in the neck or in the mediastinum. Techniques used for localization of these ectopic adenomas include sonography, computed tomography scanning, venous sampling, digital angiography, and selective arteriography. Of these techniques, selective arteriography not only has been precise but also offers the possibility of therapy. A small group of patients who underwent embolization of ectopic parathyroid adenomas through the angiographic catheter was reviewed 6 years ago with the cautious suggestion that this technique, under highly specialized indications, might offer a percutaneous treatment of hyperparathyroidism in selected patients. Since the time of the preliminary report, radiologic techniques have been modified, indications for patient selection have been refined, and experience with this method of managing persistent hyperparathyroidism has increased. It is the purpose of this report to summarize this experience with long-term follow-up of those patients treated by transcatheter staining.

Adenoma↗
PubMed1982

Shoulder arthropathy in primary hyperparathyroidism.

An erosive arthropathy of the hands and wrists has been recognized in patients with primary and secondary hyperparathyroidism [3, 5]. Recently, intra-articular erosions of the humeral head were described in six patients who had been on chronic long-term hemodialysis with secondary hyperparathyroidism [1]. We would like to present the finding of shoulder erosions in four patients with primary hyperparathyroidism and one patient with renal osteodystrophy and suggest that the humeral erosion can occur in both an intra-articular and peri-articular location.

Aged↗
PubMed1982

The role of surgery in patients with Zollinger-Ellison syndrome (ZES) managed medically.

From 1975 to 1981, the authors' deliberate intent was to treat all patients with Zollinger-Ellison syndrome (ZES) medically. This allowed the authors to ask the question of the need for surgical intervention in patients managed medically. Twenty-six patients followed for an average of 37 months (range 2 to 147 months) from diagnosis were maintained on cimetidine for a mean of 32 months (2 to 64 months). Six of these patients (23%) were unable to be maintained on cimetidine and required surgery during this period. Four received total gastrectomy, and two had lesser operations. Analysis of survival curves in this small group does not illustrate a difference between outcome based on surgical or medical management. Prospective studies based on aggressive attempts at preoperative localization with staging laparotomy and tumor resection seem justified.

Adult↗
PubMed1982

Computed tomography of the liver and kidneys in glycogen storage disease.

Glycogen, in concentrations encountered in von Gierke's disease, has computed tomography (CT) attenuation coefficients in the 50 to 70 Hounsfield unit (HU: 1,000 scale) range and accounts for the increased density of the liver. However, in eight patients with Type I glycogen storage disease, simultaneous hepatic infiltration with fat and glycogen led to a range of liver CT densities from 13 to 80 HU. Fatty infiltration may facilitate the demonstration of hepatic tumors in older patients with this disease. Half the patients showed increased attenuation coefficients of the renal cortex, indicating glycogen deposition in the kidneys.

Adolescent↗
PubMed1982

Digital subtraction angiography and dynamic computed tomography in the evaluation of arteriovenous malformations and hemangioblastomas of the spinal cord.

Digital subtraction angiography (DSA) and dynamic computed tomography (DCT) were used in the evaluation of five patients with surgically approachable vascular lesions of the spinal cord, including three arteriovenous malformations (AVM), one hemangioblastoma, and one lesion with a questionable radiographic-surgical diagnosis (AVM? hemangioblastoma?). Digital subtraction angiography was positive in three of the five cases and was particularly informative in the patient with hemangioblastoma, even vis a vis arteriography, which is considered the definitive diagnostic test for these lesions. Dynamic computed tomography was positive in four of the five cases. From this preliminary study, DSA and DCT appear to be useful screening and follow-up procedures which, in a number of aspects, complement each other.

Angiography↗
PubMed1982

CT findings in Addison's disease.

The computed tomographic findings in five patients with depleted adrenal cortical reserve were evaluated. A single patient with idiopathic adrenal atrophy revealed small adrenal remnants bilaterally. Three patients with tuberculosis demonstrated dense calcification in one or both adrenal beds without evidence of normal glandular remnants. On patient and active histoplasmosis showed enlarged nonhomogeneous glands of normal contour, a possible clue in distinguishing acute granulomatous adrenalitis from primary or secondary intraadrenal tumors.

Addison Disease↗