Sensitivity of radionuclide isotope brain scan in cerebral melioidosis: case report.

Melioidosis, an unusual infectious disease formerly confined to the Orient, is being seen with increasing frequency in the United States. We present a report of a patient who had recently traveled in the Far East and subsequently developed pulmonary melioidosis complicated by a fatal encephalitis. Although the radionuclide brain scan was markedly abnormal, computed tomographic studies were minimally abnormal on one occasion and within normal limits on another. The radionuclide brain scan appears to have greater sensitivity in diagnosis of early encephalitis and, therefore, may be the more valuable of the two studies in the diagnosis of this disorder.

Plague and the gallium scan: Case report.

Inflammation in the right axillary lymph nodes and the meninges was detected by 67Gacitrate scans in an 11-year-old boy with Yersinia pestis infection. This case provides another example of 67Ga localizing to areas of infection, indicating potential utility in future cases of bubonic plague.

Test for alcoholic cirrhosis by conversion of [14C]- or [13C]galactose to expired CO2.

After ingestion of galactose (10 g per m2) labeled with 14C or 13C, breath was collected from subjects at intervals for 4 hr followed by measurement of 14CO2 by liquid scintillation counting or of 13CO2 by mass spectrometry. Nine subjects without liver disease and 21 "cirrhotic" patients were tested with 14C; 8 control subjects and 4 patients with diagnosis of cirrhosis were tested with 13C. The mean rates of expiration of labeled CO2 by the patients with "cirrhosis" were one-third to one-half of mean normal rates during the first 90 min. The time of peak concentration of tracer CO2 for cirrhotic patients (150 to 180 min) was later than for normal subjects (90 to 120 min). There was distinctly greater separation between control and liver disease groups by test of 14CO2 radioactivity at 1 hr than by serum alkaline phosphatase, total bilirubin, and transaminase, but only slightly better separation than by serum albumin concentration (which was highly correlated with 14CO2 output). The [14C]galactose test is simpler than the standard intravenous galactose tolerance test, and , like the latter, appears superior to some other tests for recognition of cirrhosis. The use of 13C provides an example of a new direction for clinical application of this stable, nonradioactive nuclide.

Characterization of normal brain tissue using seven calculated MRI parameters and a statistical analysis system.

A statistical analysis system for classifying normal brain tissue has been applied to the analysis of MRI scans on 45 volunteers. The Bayes Maximum Likelihood method was used to achieve a discrimination accuracy of 84% for 13 tissue types among three age group sets, with classification accuracies for individual regions ranging from 50 to 100%. In order to attain this level of discrimination a set of seven derived relaxation-type parameters was used to categorize the tissue types. Values for these experimentally estimated parameters were derived from the MRI intensities of eight images in the following pulse sequences: (1) a Carr-Purcell-Meiboom-Gill (CPMG) four-echo train, (2) a single-echo inversion recovery, and (3) three single-echo sequences with varying repetition times, TR, and echo delays, TE. The T2 values derived from ratios of single-echo intensities showed better discrimination power than those from the four-echo CPMG train. The general precision of the seven estimated parameters was excellent, with percentage standard deviations ranging from 4 to 18% for the various regions studied. The tissue discrimination achieved by use of just three relaxation parameters, T1, T2, and proton density, calculated from intensities of images from a four-echo sequence, an inversion recovery sequence, and a short TR single-echo sequence, was not as good, being only 55%.