Colorectal hemangioma: radiologic findings

The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.     

Simultaneous measurement of gallbladder emptying with cholescintigraphy and US during infusion of physiologic doses of cholecystokinin: a comparison

Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying.     

Risks of gastrointestinal bleeding during secondary prevention of vascular events with aspirin--analysis of gastrointestinal bleeding during the UK-TIA trial.

From 1979 to 1985 2435 patients having had transient ischaemic attacks (TIAs) or minor ischaemic strokes, were enrolled in the UK TIA trial and were randomised to receive either aspirin 300 mg, daily or aspirin 1200 mg or placebo. Analysis of reported upper gastrointestinal bleeding events (defined as haematemesis or melaena, or both) showed a risk of bleeding in a dose dependent manner, odds ratios (95% CI) for 300 mg of aspirin = 3.3 (1.2 to 9.0) and for 1200 mg = 6.4 (2.5 to 16.5) and, as would be expected, an increased risk of hospitalisation because of bleeding also in a dose dependent manner, odds ratio = 3.6 (0.7 to 17.2) for 300 mg and 8.7 (2.0 to 37.6) for 1200 mg. Further analysis suggested greater risks of bleeding from duodenal ulcers than gastric ulcers and that bleeding is more likely early in the course of treatment with aspirin used as secondary prevention. There was also an increased risk of lower gastrointestinal bleeding, defined as fresh blood per rectum for both doses of aspirin, odds ratio 1.8 (0.5 to 6.1) for 300 mg of aspirin, and 1.5 (0.4 to 5.3) for 1200 mg of aspirin.     

MR imaging of blood vessels using three-dimensional reconstruction: methodology

Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.     

Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT

A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.     

Treatment with histamine H2 antagonists in acute upper gastrointestinal hemorrhage. Implications of randomized trials

Histamine H2 antagonists are widely used in treating patients with hematemesis and melena, despite the lack of reliable evidence of benefit from any of the randomized trials, considered separately. Examination of the data from all 27 available randomized trials, in which over 2500 patients were entered, suggests that treatment may reduce the rates of rebleeding, surgery, and death by about 10, 20, and 30 per cent, respectively, although these results were only marginally significant for surgery and death. Any benefit appeared to be confined to patients with bleeding gastric ulcers, but since this subgroup analysis was prompted by preliminary examination of the data in some of the individual trials reviewed here, it should be treated with particular caution. The implications of this overview are that treatment with histamine H2 antagonists appears to be moderately promising, but its effects on important end points, such as death, still need to be assessed reliably. Prevention of "only" about 20 per cent of all deaths could well be worthwhile, for the condition is common, and the treatment widely practicable. To detect such a moderate effect reliably, however, might require the randomization of 10,000 patients (or more), which would be possible only in an extremely simple multicenter collaborative trial.     

A capacitive method of measuring circadian activity in laboratory animals

An activity monitor is described which enables the activity of a variety of laboratory animals to be analysed quantitatively at low cost. Essentially the monitor consists of an oscillator which is sensitive to changes in the impedance of an antenna attached to it. The movement of the laboratory animal produces a change in antenna capacitance, which in turn causes the frequency of the oscillator to alter. This change in frequency produces, at a different point in the circuit, a corresponding change in voltage, which is amplified to drive a recorder. Tests have demonstrated the high degree of flexibility of the monitor, which has operated successfully in three different media, sensing the activity of a cinnamon shrew in an open cage, a golden mole underground and crabs under water.     

Short-term reduction in bone markers with high-dose simvastatin

The effect of statins on bone mass and fracture rates is uncertain. Therefore, we investigated whether statin therapy acutely altered bone turnover as measured by changes in bone serum markers (bone-specific alkaline phosphatase, osteocalcin, and type I collagen N-telopeptide cross-links). Fasting blood samples were obtained from 55 (M/F 39/16) healthy nonsmoking adults (mean ± standard deviation: age, 50.4±7.5 years; body mass index, 27.8±4.9 kg/m²) with low-density lipoprotein cholesterol concentrations between 3.38–4.90 mmol/l. Subjects were randomized to four possible 8-week treatment regimens: placebo (n =14), pravastatin 40 mg/daily (n =12), simvastatin 20 mg/daily (n =14) or simvastatin 80 mg/daily (n =15). High-dose simvastatin (80 mg/daily) produced a significant reduction in bone-specific alkaline phosphatase as compared with other treatment regimens (p =0.009). However, there were no changes in urinary N-telopeptide cross-links, a sensitive marker of bone resorption. Short-term use of high-dose simvastatin lowers the level of the serum bone marker bone-specific alkaline phosphatase, which suggests the possibility of reduced bone turnover.