Physical and clinical evaluation of high-resolution thyroid pinhole tomography.

UNLABELLED: High-resolution pinhole-SPECT (PSPECT) is a new method for examining the thyroid gland. METHODS: The camera is tilted slightly so that it is as close to the thyroid as possible. Patients are injected with 185-260 MBq (5-7 mCi) of [99mTc]pertechnetate and examined for 20 min. The reconstruction algorithm is based on filtered back-projection. RESULTS: We performed static scintigraphy on the thyroids of 114 patients, followed by PSPECT. The major advantage of P SPECT is high resolution. Three- and 4-mm-pinholes produce resolutions of 6 mm and 7 mm, respectively, while resolutions obtained with a parallel collimator are always above 15 mm. The second advantage associated with this method is the good visualization of the cold nodules surrounded by higher activity. Finally, the reconstruction program provides exact sizes of thyroids. CONCLUSION: SPECT is a powerful tool for examining the thyroid.

B-N-acetyl hexosaminidase (B-NAH) serum levels after endotoxin administration into the portal vein in the rat.

Endotoxin was injected directly into the portal vein in rats with and without common bile duct (CBD) ligation. B-N-acetyl hexosaminidase (B-NAH) activity levels in the serum were found to be significantly elevated 24 h later in both groups. Serum bile acid levels were found to be significantly higher in the endotoxin-injected groups of rats compared to controls. Thus, endotoxin, as well as bile acids, may cause damage to Kupffer cell membranes, resulting in accumulation of B-NAH in rat serum.

[Isotope lymphography and its therapeutic implications]. / La lymphographie isotopique et ses implications thérapeutiques.

Radiological lymphography presents drawbacks among which the risk of aggravation of the edema is most prominent. The authors report their experience with isotopic lymphography which best reproduces the physiological conditions of lymphatic drainage; it provides informations on the dermal or canalicular drainage route, the possible peripheral stasis or lymph leakage.

Diagnostic value of antithrombin III and aminopyrine breath test in liver disease.

To assess the value of the aminopyrine breath test (ABT) and antithrombin III (AT III) determinations in liver disease, both tests were performed on 77 consecutive patients who underwent liver biopsies for increased values of liver enzymes and in 20 patients with clinical cirrhosis. The mean values of AT III and ABT were significantly lower in cases of liver cirrhosis than in cases of steatosis and steatofibrosis. The AT III and ABT values were abnormal in, respectively, 83.9% (26/31) and 90.3% (28/31) of the patients with cirrhosis and 22.7% (15/66) and 28.8% (19/66) of the patients without cirrhosis. The association of the two tests increased the specificity without modifying the sensitivity. Both the AT III test and the ABT can be used as noninvasive diagnostic procedures for cirrhosis in patients for whom the liver biopsy is not available or contraindicated.

Technetium-99m MDP vs technetium-99m dicarboxypropane diphosphonate. A clinical comparison in various pathologic conditions.

The performance of Tc-99m MDP vs Tc-99m dicarboxypropane diphosphonate (DPD) was evaluated in 20 patients with various skeletal bone diseases. Each patient was investigated twice, with an interval of three days between studies and using the same protocol, hence each case served as its own control. The results were: In a subjective interpretation by five independent and experienced investigators, the difference between agents was small, yet in favor of MDP. Region of interest (ROI) analysis of the pooled results in 74.4% of all cases shows a higher bone lesion to normal bone ratio (BL/NB), and in 79.3% of all cases, a better bone lesion to soft tissue ratio (BL/ST) with Tc-99m MDP. When considering pathology types separately, the BL/NB ratio of Tc-99m MDP was 17.7% higher than the one of Tc-99m DPD in metastases, 9.5% higher in rheumatoid arthritis, 2.8% higher in metabolic diseases, and 24% higher in bone fractures. Student's paired t test on the pooled BL/NB ratios shows a difference of 15.5% for Tc-99m MDP, significant at P = 0.00155. The overall results of our study favor Tc-99m MDP.

Quantitative analysis of diethyl-IDA reflux. Comparison of controls and dyspeptic, gastric ulcerated, and gastrectomized patients.

The administration of a radioactive tracer through the liver cell and the elimination of bile following an induced vesicular contraction permits duodenogastric reflux to be objectively diagnosed without intubation. This quantitative study of the reflux using 99mTC diethyl-IDA is based on 214 patients and demonstrates: 1) a frequent association with the gastric ulcer, 2) a considerable frequency in gastric resection surgery with duodenogastric anastomosis, 3) a constant occurrence in gastric resection surgery using jejunogastric anastomosis. These findings point to the involvement of biliopancreatic reflux in the genesis of gastric ulcer as well as gastritis and carcinoma of the gastric stump.

A chemical method for the labeling of fibrinogen with 99mTc.

A new method allowing the labelling of fibrinogen with 99mTcO4- is described. The 99mTcO4- is reduced by stannous chloride in an alkaline medium. After 1 h incubation with fibrinogen, the pH was brought down to 7.1. The study of (1) the pH of the solution, (2) the quantity of the reducer, and (3) the time of incubation allowed us to specify optimal conditions for labeling. The labeling yield varied from 91.68% plus or minus 6.05% to 95.18% plus or minus 2.13% according to the method of control used: the precipitation of fibrinogen by (NH4)2SO4 25% or thin-layer chromatography with methylethylketone as solvent. Clottable radioactivity averaged 72% plus or minus 4.43%. Column chromatography separated the tracer into two radioactive peaks. The first peak corresponded to the fibrinogen and carried 73.36% plus or minus 5.8% of the total radioactivity. The total recovered radioactivity amounted to 89.86% plus or minus 8.07%. Spectroscopic clottability was 88.23% plus or minus 2.42%. The in vivo stability of the labeling and the molecule was followed for 24 h after intravenous injection. If the radioactivity measured in the 5 min sample was considered to equal 100%, the 24 h sample averaged 32.71% plus or minus 3.25%, of which 85.68% plus or minus 2.92% was recovered in the clot. In conclusion, this method enabled us to obtain a stable tracer that we used for routine investigations in man.

The interpretation of phlebograms using fibrinogen labeled with 99 mTc.

A new method for the detection of deep-vein thrombosis is presented, consisting of a single antecubital injection of fibrinogen labeled with 99mTc. This atraumatic procedure allows one to visualize the large veins of the lower limbs, the venae iliacae and the distal part of the vena cava inferior. This paper discusses how to interpret these phlebograms.

Usefulness of 99mTechnetium pertechnetate in periarteritis nodosa.

Radioisotopes have a wide range of application in the clinical investigation of many organs. Muscle diseases are an exception in this expanding field. We report here a case of periateritis nodosa in which unusual scintigraphic images were obtained with 99mTc-pertechnetate. The kinetics of this isotope and the scintigraphic changes were followed during treatment and found to be useful clinical tools.