BACKGROUND: To determine the accuracy and safety of a modified intra-arterial calcium stimulation with the venous sampling test (ASVS) for preoperative localization of insulinomas. Modification included stimulation with a fixed low dose of calcium gluconate, additional stimulation in the distal splenic artery, and no insulin sampling in the left hepatic vein. METHODS: In 10 patients showing biochemical evidence of organic hyperinsulinemia, 0.45 mmol of Ca2+ was injected into the gastroduodenal, superior mesenteric, proper hepatic, proximal, and distal splenic arteries during angiography. Insulin levels were measured in samples taken from the right hepatic vein before and 30, 60, 90, 120, 180, and 300 s after Ca2+ injection. RESULTS: Insulin gradients with an increase of more than fourfold indicated direct tumor supply, two- to fourfold correlated with collateral supply, and less than twofold correlated with normal tissue vascularization. ASVS localized all the adenomas of the pancreatic head (n = 3) and body (n = 2) and two of four adenomas of the tail correctly, as confirmed by surgery. Two adenomas of the proximal pancreatic tail were erroneously localized to the body segment, but the fault was rectified by angiography. In one patient with a negative ASVS and without exploration, the diagnosis of an insulinoma was revised. CONCLUSION: ASVS with a fixed low dose of calcium gluconate is a highly accurate and safe method for preoperative localization of insulinomas. Sampling in the left hepatic vein can be routinely omitted. Additional stimulation in the distal splenic artery seems helpful in surgical decision making, but additional experience is needed.

Adult↗

PubMedDate not supplied

Customized medical image databases: a low-cost approach.

The increasing use of digital images in medicine creates a demand for efficient but simple methods to store, retrieve and display images. The ideal solution for this might be a large-scale hospital-integrated picture archiving and communication systems, but this is not applicable under all conditions. A small-scale, user-defined image database running on a desktop computer may fit the individual needs better, while yielding optimal cost-effectiveness. We will present a way to create customized image databases using a general-purpose desktop database system and a specialized, dedicated image handling component programmed in C++.

Cost-Benefit Analysis↗

PubMedDate not supplied

Intracranial amebic abscesses: CT and MR findings.

The CT and magnetic resonance findings in a case of intracranial amebic abscesses are described. Due to increased travel to endemic areas, amebic abscess should also be included in the differential diagnosis for patients who live in the temperate parts of the world.

Animals↗

PubMedDate not supplied

Thrombus formation in deep venous thrombosis. A clinical approach to diagnosis and control of lysis efficacy.

The efficacy of fibrinolysis in deep venous thrombosis (DVT) depends on the age and organization of the thrombus as well as its localization. Up to now, indication for lysis therapy is defined according to the duration of clinical symptoms (less than 7 days). Our lysis results in urokinase therapy (n = 87) with high-dose and long-term regimen (mean 7.8 days), however, have shown no correlation between the duration of clinical symptoms (up to six weeks) and lysis efficacy (p less than 0.05). Therefore phlebographic criteria were established to allow the differentiation of fibrinolytic therapy depending on the site of the thrombus, its localization and the formation of collateral veins. In order to determine the state of thrombus organization, we used a new ultrasound Duplex system device (ARTIS, 7.5 Mhz, Picker International). In vivo experiments with induced thrombosis in human vena saphena magna demonstrate that echodensity of thrombi in ultrasound starts at the 11th-15th day. These findings are in good agreement with pathological studies of thrombus formation. Recent results of 24 patients with DVT indicate that echodensity of thrombus in ultrasound correlates with the course of organization and the efficacy of later lysis therapy.

Adult↗