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J L Doppman

Publications and source records attributed to J L Doppman.

465 records · Page 26Linked to original sources
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CT evaluation of hepatic and splenic trauma with EOE-13. An experimental study in monkeys.

EOE-13 is a liver-spleen specific CT contrast agent currently undergoing clinical trials. It is an aqueous emulsion of iodinated fatty acids. We studied eight rhesus monkeys with surgically created blunt trauma to the liver and spleen. The animals were examined using CT scans without contrast material and CT scans with EOE-13. Scans were performed at times between 3 hours and 24 hours after trauma. The presence of parenchymal injury was shown better EOE-13 (P less than 0.01). The use of EOE-13 permitted earlier diagnosis in both the liver and spleen. This contrast agent has potential for the evaluation of trauma in clinical practice, and may be particularly useful in children.

Animals↗
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MR imaging of pheochromocytomas.

Magnetic resonance imaging (MRI) of seven patients with pheochromocytomas demonstrable by CT was performed. Magnetic resonance imaging showed all primary pheochromocytomas, as well as metastatic lesions to the thorax, retroperitoneum, and liver. The ability to distinguish pheochromocytomas from surrounding structures without the need of an intravenous contrast agent and to provide direct coronal and sagittal images suggests that MRI may be useful in detecting and localizing these tumors.

Adolescent↗
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Distinction between adrenal adenomas and metastases using MR imaging.

Magnetic resonance imaging was performed on 12 patients with known neoplastic disease and adrenal masses shown by CT. Three patients with metastases had high signal intensity in the adrenals on T2 weighted spin echo scans (SE 2,500/80) and nine patients with nonfunctioning adenomas had low signal intensity on T2 weighted images. The ability to distinguish metastases from nonhyperfunctioning adrenal adenomas may be of use in the pre-operative evaluation in patients with known carcinoma and incidental adrenal masses.

Adenocarcinoma↗
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Opening of blood-ocular barrier demonstrated by contrast-enhanced MR imaging.

Opening of the blood-ocular barrier following infusion of hyperosmolar agents into the internal carotid artery has been demonstrated by gadolinium enhanced magnetic resonance (MR) imaging. In five rhesus monkeys the disruption of the barrier was shown as increased signal intensity within the aqueous and vitreous humors. These findings suggest a potential use of contrast-enhanced MR imaging for detecting and evaluating the ocular microangiopathy of diabetic and hypertensive retinopathy and other diseases.

Animals↗
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Gadolinium DTPA enhanced MR imaging of ACTH-secreting microadenomas of the pituitary gland.

Gadolinium diethylenetriamine pentaacetic acid (DTPA) enhanced magnetic resonance imaging was performed in eight patients with Cushing disease and surgically proven pituitary microadenomas. A 1.5 T scanner was used with 3 mm contiguous slices. Short repetition times (TR), short echo times (TE), and long TR, long TE sequences were obtained before and serially after intravenous administration of Gd-DTPA. Three of eight (38%) microadenomas were undetectable both without and with Gd-DTPA: one post-Gd-DTPA scan was false positive on the side opposite the adenoma. Hemihypophysectomy based on a petrosal sinus adrenocorticotropic hormone (ACTH) gradient cured all three patients. Two microadenomas (25%) were visible as hypointense foci following Gd-DTPA but not on unenhanced scans. The remaining three microadenomas (38%) were seen before and after Gd-DTPA on T1-weighted images. In this small series of ACTH-producing microadenomas, one-third were seen on unenhanced 1.5 T scans, one-third were seen only after Gd-DTPA, and one-third were not imaged even with Gd-DTPA enhancement.

Adenoma↗
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Radiologic screening for von Hippel-Lindau disease: the role of Gd-DTPA enhanced MR imaging of the CNS.

Thirty-seven members of a family with von Hippel-Lindau disease (VHL) were prospectively screen for CNS hemangioblastomas; 10 family members were previously known to have VHL. Radiographic studies included noncontrast magnetic resonance (MR) imaging of the head (all patients) and spine (34 patients) and contrast-enhanced CT (CCT) of the head (all adult patients). Eleven patients had Gd-DTPA enhanced MR (CMR) of the head and 10 patients had CMR of the spine. Sixteen patients had radiographic evidence of CNS hemangioblastomas and all but six patients were symptomatic. Using comparable studies, CMR of the head demonstrated more lesions than the other modalities (31, 22, and 19 for CMR, MR, and CCT, respectively). Furthermore, CMR better separated tumor from edema, as well as cystic from solid components. Contrast enhanced MR was superior to noncontrast MR of the spine in lesion detection (31 vs. 4; p less than 0.001). Noncontrast MR was particularly limited in four patients with syringomyelia. We conclude that postcontrast MR of the head and spine is the best currently available means of detecting hemangioblastomas associated with VHL.

Adolescent↗
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CT and MR imaging of massive macronodular adrenocortical disease: a rare cause of autonomous primary adrenal hypercortisolism.

We studied four patients with adrenocorticotropic hormone (ACTH)-independent hypercortisolism due to bilateral massive enlargement of the adrenal glands. The combined weight of the adrenal glands ranged from 69 to 149 g and the adrenal cortex was replaced in three of four patients by multiple nodules ranging from microscopic to 4 cm in diameter. One patient had massive diffuse enlargement. All patients had low or undetectable levels of serum ACTH, absence of petrosal sinus to peripheral gradients of ACTH in bilateral samples from the inferior petrosal sinuses before and after stimulation by corticotropin releasing hormone, and absence of an adenoma on MR imaging of the pituitary gland. The marked degree of adrenocortical enlargement and absence of ACTH dependency separates this massive macronodular disease from the more common ACTH-dependent macronodular hyperplasia encountered in older patients with pituitary-dependent Cushing disease. All patients required bilateral adrenalectomy to control hypercortisolism. We present the spectrum of nodular adrenal disease associated with hypercortisolism and a differential diagnosis based on morphologic criteria.

Adrenal Cortex Diseases↗
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Ultrasonic investigation of pancreatic islet cell tumors.

Ultrasonographic imaging was performed on 49 patients who had pancreatic islet cell tumors, including examples of all six known tumor varieties. In beta cell insulinomas, ultrasonography was of little value for tumor visualization, because these tumors tend to be small and the patients frequently are obese. On the other hand, ultrasonography was very effective for evaluating the nonbeta cell tumors, detecting both primary pancreatic neoplasms and hepatic metastases in patients with glucagonomas, somatostatinoma, non-functioning tumors, and the WDHA syndrome. In detection of the Zollinger-Ellison syndrome, ultrasonography compares favorably with previously reported gastrinoma detection by angiography and CT scanning.

Adenoma, Islet Cell↗
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Direct infusion of EOE-13 into the hepatic artery. Experimental evaluation of safety in monkeys.

Ethiodized Oil Emulsion 13 (EOE-13) is an intravenous liver-spleen specific CT contrast agent. We infused EOE-13 directly into the hepatic arteries of five rhesus monkeys. Normal saline was administered in the same fashion in two control animals. Serial laboratory studies showed no major toxicity over a seven-day period. Intra-arterial EOE-13 has potential usefulness in the evaluation of hepatic artery infusion chemotherapy.

Animals↗
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Intraarterial digital subtraction angiography of spinal arteriovenous malformations.

Intraarterial digital subtraction angiography (DSA) in two patients with spinal dural arteriovenous fistulas demonstrated the major feeding arteries and the venous drainage of the respective malformations. However, the dural component of the malformations--which distinguishes them from intradural malformations--could not be recognized, nor was normal cord vasculature demonstrated. In a patient with an intradural arteriovenous malformation (AVM), only major arterial feeders were demonstrated. Intraarterial DSA provides essential anatomic information with an increased margin of safety in spinal AVMs, but supplemental selective arteriography, conventional or digital, also is currently required.

Angiography↗
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Anatomy of the junction of the inferior petrosal sinus and the internal jugular vein.

PURPOSE: To evaluate the anatomy of the junction of the inferior petrosal sinus and the internal jugular vein. METHODS: Using a previously described classification system, we prospectively classified venous anatomy bilaterally in 135 of 136 persons consecutively undergoing inferior petrosal sinus sampling. RESULTS: Type IV anatomy, with no anastomosis between the inferior petrosal sinus and the internal jugular vein, was significantly less frequent in our series than in a previous series (1 versus 7%; P < .001). Venous anatomy did not differ significantly between the left and the right junctions or between men and women. Venous anatomy was symmetric in only 65% of subjects (86 of 133). We describe an uncommon variant anatomy, incomplete type IV, found in 4.5% of our subjects (six of 133), that may cause incorrect results of petrosal sinus sampling. CONCLUSION: Bilateral sampling of pituitary venous effluent can be accomplished by the methods described, despite the presence of either incomplete or true type IV venous anatomy. Bilateral petrosal sinus sampling is anatomically possible in 99% of persons.

Adolescent↗