Ten patients with diabetic gastroparesis were selected for a randomized, double-blind, controlled trial of metoclopramide. Each patient had longstanding insulin-requiring diabetes mellitus and symptoms of gastric stasis. The patients were evaluated for the symptoms of gastric stasis and radionucleotide gastric emptying was measured before the patients entered the study and after they were given either metoclopramide or placebo treatment. Metoclopramide, 10 mg orally, stimulated an increase in the rate of gastric emptying (56.8% +/- 7.4%) in contrast to the response to placebo (37.6% +/- 7.7%) (p less than 0.01). The overall symptoms and symptoms of vomiting were markedly reduced during metoclopramide treatment in contrast to those during placebo treatment. Before the study five patients were constipated (less than three bowel movements per week); during metoclopramide treatment the patients' bowel habits were improved. There was a poor correlation between improved gastric emptying and decreased symptoms. Metoclopramide may improve symptoms of diabetic gastric stasis through two mechanisms: its peripheral effect on gastric smooth muscle, which increases gastric emptying; and its central effects on the chemoreceptor vomiting zone, which decrease nausea.

Gadopentetate dimeglumine is an intravenous contrast medium used in magnetic resonance imaging. To determine its safety, the authors summarized data concerning adverse reactions, laboratory parameters, and other assessments for 1,068 adult patients who received gadopentetate dimeglumine in United States clinical trials. For all studies, 213 of 1,068 patients (19.9%) who received gadopentetate dimeglumine experienced one or more clinical adverse reactions. Most of these reactions were minor and short-lived. Hematologic, blood chemistry, and urinary evaluations showed no apparent drug-related effects, with the exception of a transient, asymptomatic rise in serum iron and bilirubin levels in some patients. Other safety assessments--electrocardiography, electroencephalography, neurologic examinations, and vital signs--showed no clinically significant trends in change from baseline results. It was concluded that gadopentetate dimeglumine demonstrated a high degree of safety and tolerance.

Approximately 250 computed tomography (CT) systems were surveyed in a nationwide study to determine the average radiation dose resulting from a typical adult head procedure. The multiple scan average dose (MSAD) was selected as the dose descriptor. For the typical adult CT head procedure, the MSAD was generally within 2.2-6.8 rads (22-68 mGy). Variations in dose by a factor of two or more were often seen for a given manufacturer and model. These dose ranges indicate a potential to reduce dose by carefully selecting imaging techniques. Overall, variations in dose can result from differences in the user's choice of technique (desired image quality) or from actual differences in scanner performance (caused by differences in collimation, filtration, or geometry). To use CT appropriately, a facility should consider dose as well as image quality in selecting optimal techniques for typical modes of operation.

Both the diagnostic accuracy and sensitivity of the MRI diagnosis of central nervous system neoplasms appear to be improved by the administration of a paramagnetic contrast agent, Gd DTPA.

No abstract