[en] This article reviews different concepts of functional evaluation of the liver and biliary ducts with sup(99m)Tc labeled iminodiacetic acid derivatives. Authors insist on physiologic and pathophysiologic aspects of the radionuclide evaluation of the biliary tract. Technical data necessary to get good results are presented. The authors review the clinical application of sup(99m)Tc-iminodiacetic acid cholescintigraphy in the investigation of the intra or extra biliary ducts, in the early or delayed detection of complications following biliary surgery and in the evaluation of the gastric or oesophageal biliary reflux

[en] Fifty-two patients with proven primary lung cancer who were referred for mediastinoscopy were prospectively studied with Tc-99m glucoheptonate and Ga-67 citrate thoracic scintigraphy. Primary lung tumors concentrated Ga-67 in 92% of cases, compared to 88% for Tc-99m glucoheptonate. Mediastinoscopy confirmed the presence of mediastinal metastases in 23 patients. The sensitivity of Tc-99m glucoheptonate and Ga-67 scans for mediastinal involvement detection is respectively 52% and 83%, for a specificity of 100% (Tc-99m glucoheptonate) and 88% (Ga-67). Twenty-nine patients underwent thoracotomy after a negative mediastinoscopy. Hilar metastatic involvement was present in eight patients. The sensitivity and the specificity for detection of hilar involvement were respectively 63% and 95% for Tc-99m glucoheptonate and 88% and 78% for Ga-67. Although more specific than Ga-67 scan, Tc-99m glucoheptonate thoracic imaging cannot be recommended in the staging of lung cancer because of its low sensitivity in the detection of intrathoracic metastatic spread of primary lung carcinoma

[en] A new radiochemically stable Tc-99m brain imaging agent has been characterized recently in humans. Tc-99m ethyl cysteinate dimer (ECD) is neutral, lipophilic, and rapidly crosses the blood-brain barrier, where it is retained in the brain with minimal washout for hours. Sequential SPECT studies in eight normal volunteers indicate that the distribution pattern of the radiopharmaceutical is similar to the distribution pattern observed with other brain perfusion agents. Brain image quality is excellent because clearance from background facial areas and lungs is rapid. These results suggest that ECD is a promising radiopharmaceutical for brain perfusion scintigraphy

[en] Published in summary form only

[en] We have compared [Tc-99m] sodium pertechnetate with Tc-99m glucoheptonate in 52 patients studied for various brain lesions. Flow studies as well as delayed scans were performed in all. Especially in primary and metastatic lesions of the posterior fossa, the diagnostic yield was improved by the delayed glucoheptonate (GH) scans. In contrast, no advantage of GH over pertechnetate could be detected in the study of infarcts or other ischemic lesions. Various hypotheses are discussed to explain the observed differences in behavior between the two tracers

[en] We study an SO(4) x U(1) extension of the standard model of weak and electromagnetic interactions, which accommodates the new leptons postulated as an explanation for trimuon events. Universality is shown to be natural in the model. A phenomenological analysis gives good agreement with present data

[en] Although the diagnostic utility of Tl-201 myocardial imaging after dipyridamole (DIP) infusion is well established, the intravenous form of the drug is not commercially available. The author prospectively studied 34 consecutive patients referred for coronary angiography. With in a 2 week period, each patient underwent cardiac catheterization and Tl-201 myocardial imaging following both oral and i.v. DIP. With the patient supine, DIP was infused at a rate of 0.56 mg/kg over 4 minutes. Tl-201 was injected 3 min. after the end of the infusion with the patient standing. Myocardial imaging was performed in 3 views at 3 min. and 4 hrs after Tl-201 injection. All patients were then randomized to either 200 mg or 400 mg of oral DIP. Imaging protocol was similar to the i.v. technique, except for a delay of 45-60 min. before Tl-201 injection. Myocardial regional perfusion was evaluated by 2 independent observers using original analog and background substracted digital images with segmental profile analysis. For the 17 patients who recieved DIP 400 mg, the sensitivity was 75%(9/12) with the infusion and 83% (10/12) with the oral dose. Side effects were minor and less frequent with the oral DIP. Despite the small number of patients studied, Tl-201 imaging following 400 mg oral DIP administration proved to be reliable alternative to the intravenously induced coronary vasodilation

[en] Published in summary form only

[en] Although the diagnostic utility of thallium-201 myocardial imaging after dipyridamole infusion is well established, the intravenous form of the drug is not yet commercially available in North America. Fifty patients referred for coronary angiography were prospectively studied. Within a 2 week period, each patient underwent cardiac catheterization and thallium-201 myocardial imaging after both oral and intravenous dipyridamole administration. For the oral protocol, patients were randomly assigned to treatment with either 200 or 400 mg of dipyridamole in tablet form. Coronary artery stenoses of 70% or greater were considered significant. For the 25 patients who received a 200 mg oral dose of dipyridamole, the scintigraphic study showed perfusion defects in 65% of patients with significant coronary artery disease after the oral dose and in 85% of patients after the intravenous dose. For the 25 patients who received a 400 mg oral dose, the sensitivity of the scintigram was 84% after the oral dose and 79% after the intravenous dose. Except for headache and nausea, side effects were less severe and less frequent with oral (either 200 or 400 mg) than with intravenous dipyridamole. Because of the delayed and variable absorption of dipyridamole tablets, the oral studies required a longer period of medical supervision (45 to 60 minutes), and aminophylline was empirically administered after completion of the first set of thallium-201 images. It is concluded from this study that thallium-201 myocardial imaging after coronary vasodilation with a 400 mg oral dose of dipyridamole is a safe, widely available and reliable alternative for the evaluation of coronary artery disease in patients unable to achieve an adequate exercise level on stress testing

[en] Short communication