Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results

In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients.     

Subtle gastric abnormalities in a canine model: detection with low-dose imaging with storage phosphors and its equivalence to conventional radiography

The authors compared low-dose (32% of standard exposure) storage phosphor digital imaging (system resolution: 0.2-mm pixels, 10 bits) with isovoltage 75-kVp conventional radiography (standard exposure) in the detection of subtle simulated gastric abnormalities by using air contrast barium studies. Subtle simulated abnormalities (3-7-mm polyps, 4-15-mm ulcer craters, 4-11-mm-diameter edema, and 11-12-mm linear ulcers) were produced in resected canine stomachs. Receiver operating characteristic analysis of 1,800 observations by six readers indicated that the digital images with and without high-frequency edge enhancement were equivalent to conventional radiographs (mean receiver operating characteristic areas [+/- standard deviation]: 0.76 +/- 0.06, 0.78 +/- 0.04, and 0.77 +/- 0.04, respectively). The accuracy of the diagnosis was equivalent for all three modalities. The following mean accuracies of negative and positive responses, respectively, for unenhanced digital, edge-enhanced digital, and conventional images were determined: 0.71 +/- 0.05 and 0.41 +/- 0.07, 0.71 +/- 0.04 and 0.51 +/- 0.09, and 0.68 +/- 0.04 and 0.43 +/- 0.05. It was concluded that low-dose storage phosphor air-contrast barium studies were equivalent to conventional radiography in the detection of subtle gastric abnormalities.     

Artifacts seen during CT pelvimetry: implications for digital systems with scanning beams

During computed tomography (CT) pelvimetry of two pregnant women, bony abnormalities of the fetuses were noted on the scout images that were not confirmed at delivery. To explore the cause of these artifacts, specimen long bones were manipulated in various ways during CT scout imaging. Artifacts like those seen during in vivo imaging were found to be caused by motion of the object. The CT scout view is an example of an image produced by a digital system that uses a scanning beam. This type of digital system is being used for several types of body imaging including screening for scoliosis and chest radiography. Attention to motion artifacts should decrease diagnostic errors and aid further development of these systems.     

Hepatic parenchymal gas after blunt trauma

Hepatic parenchymal gas was demonstrated by computed tomography in a boy who had sustained severe blunt trauma to the abdomen 12 hours earlier. There was no clinical evidence of infection. Although previous reports have suggested that hepatic parenchymal gas indicates the presence of infection, such gas may also be a manifestation of severe blunt trauma without infection.     

Smoking habits in relapsed subjects from a smoking cessation trial after one year

Reports of smoking cessation studies often claim that many relapsed subjects reduce their smoking. We investigated the smoking habits of relapsers 1 year after quitting in a smoking cessation trial using nicotine or placebo patches. All 289 participants in that study were summoned to a 1-year follow-up visit–148 (57%) of 259 relapsers attended, as did all 30 sustained abstainers. Fewer than 1% of the subjects had quit spontaneously after the primary relapse. Daily cigarette consumption, standard nicotine yield per cigarette, saliva cotinine concentration, expired carbon monoxide level and two nicotine dependency scales were assessed at entry and at the 1-year follow-up. In five of these six smoking-related characteristics, there was a small but significant mean reduction of 7%-27%. A significant weight gain of 0.5 ± 2.9 kg (mean ± SD) was recorded in the relapsers compared with 4.8 ± 4.2 kg for abstainers (p < 0.001). It is concluded that smoking habits in relapsers are relatively unchanged, and thus the most important outcome measure in smoking cessation trials is abstinent subjects.     

Acute meningo-encephalitis in pregnancy—a problem of differential diagnosis

Two cases of Coxsackie B viral meningo-encephalitis in pregnant women are described. Both patients recovered well and delivered healthy babies, but because of delay in establishing the aetiology of their infections both mothers, and one child, received acyclovir therapy. The differential diagnosis of non-pyogenic meningo-encephalitis in late pregnancy can present particular problems: clinicians caring for such women should remain aware of the potential for enteroviral infection in their patients, and take appropriate action to prevent cross-infection in neonatal units.