PubMed Health⌕ Search

Biomedical subjects

Lionel S Zuckier

Publications and source records attributed to Lionel S Zuckier.

11 recordsLinked to original sources
PubMed2005

The F + 0 protocol for diuretic renography results in fewer interrupted studies due to voiding than the F - 15 protocol.

UNLABELLED: Timing of diuretic administration is not universally standardized in renography. Over the past year, our practice has changed from F-15 administration of furosemide to an F + 0 protocol. Therefore, we have retrospectively compared these 2 cohorts to assess if the shorter interval between diuretic administration and study completion in the F + 0 study results in a greater frequency of patients able to complete the subsequent 30-min dynamic acquisition without disruption due to voiding. METHODS: We identified 108 diuretic (99m)Tc-mercaptoacetyltriglycine renograms performed in the previous 18-mo period. Three patients were given furosemide at 30 min after the radiopharmaceutical and were excluded. Twenty studies in children under 3 y of age were excluded from consideration because voiding is neither restricted in this age group nor does voiding into a diaper cause disruption. Forty milligrams of furosemide were administered to adults, whereas 0.5 mg/kg was given to children. In the first cohort of 56 studies, radiopharmaceutical was administered 15 min after furosemide (F-15), whereas, in the second cohort of 29 patients, it was administered immediately thereafter (F + 0). In all cases, patients were asked to void proximal to radiopharmaceutical injection. Dynamic images and renogram curves were inspected for evidence of interruption or voiding midstudy. Statistical significance was determined by a 1-tailed Fisher exact test for proportions, with P < 0.05. RESULTS: The F-15 and F+0 groups of patients were comparable in terms of age, sex, and diuretic amount. In 17 of the F-15 patients, renography was interrupted because of voiding (30%), whereas this occurred in only 3 of the F + 0 patients (10%). This difference was significant at the P = 0.033 level. The mean time of voiding was 18.3 min (range, 12-25 min) for F-15 patients and 16 min (range, 12-19 min) for the F + 0 group. CONCLUSION: The F + 0 renal diuretic protocol is associated with a significantly lower rate of disruption because of voiding than the F-15 protocol, likely due to the shorter period between diuretic administration and study termination, which results in less bladder distention and discomfort. On the basis of these data, the F + 0 protocol appears to be a more tolerable procedure.

Adolescent↗
PubMed2004

Kinetics of perrhenate uptake and comparative biodistribution of perrhenate, pertechnetate, and iodide by NaI symporter-expressing tissues in vivo.

UNLABELLED: Pertechnetate (as (99m)TcO(4)(-)), (123)I(-), and (131)I(-) have a long and successful history of use in the diagnosis and therapy of thyroid cancer, with uptake into thyroid tissue mediated by the sodium-iodide symporter (NIS). NIS has also emerged as a potential target for radiotherapy of nonthyroid malignancies that express the endogenous or transfected symporter. Perrhenates (as (188)ReO(4)(-) and (186)ReO(4)(-)) are promising therapeutic substrates of NIS, although less is known about their behavior in vivo. In this study, we endeavored to characterize the biologic behavior of perrhenate, especially in relation to iodide and pertechnetate, to better explore its possible therapeutic role. METHODS: We describe the simultaneous biodistribution and uptake in vivo of iodide, pertechnetate, and perrhenate in groups of healthy CD1 mice, either with or without coadministration of perchlorate (ClO(4)(-)), a potent NIS inhibitor. Animals administered single radiopharmaceuticals were imaged as a means of illustrating these findings. Kinetic properties of perrhenate were compared with those of iodide in a stably transfected NIS-bearing Madin-Darby canine kidney (MDCK) cell line. RESULTS: Biodistributions of iodide, pertechnetate, and perrhenate in live mice were remarkably similar. Activity in salivary gland and stomach was severalfold greater than in blood, remained elevated over the initial 2 h, and subsequently washed out. A similar pattern characterized pertechnetate and perrhenate uptake by the thyroid, in which the 2-h concentration was slightly more elevated than at the 20-min time point. However, uptake subsequently decreased by 19 h. In contrast, iodide continued to increase through the 19-h time point, presumably as a result of organification. The addition of perchlorate sharply decreased uptake of all 3 radiopharmaceuticals by the stomach, salivary glands, and thyroid and resulted in their rapid clearance, paralleling blood-pool clearance. In tissues that do not express NIS (liver, muscle, spleen), uptake of all 3 radiopharmaceuticals was low and rapidly decreased over time, paralleling blood-pool clearance. Similar findings were seen in kidney, where only minimal amounts of NIS are expressed in tubular cells. In stably transfected MDCK cells, steady-state accumulation of iodide was approximately 4-fold higher than that of perrhenate at 30 min. No active transport was demonstrated in nontransfected MDCK cell lines or after perchlorate administration. Uptake values measured at different concentrations of substrate demonstrated saturation kinetics. Apparent maximal velocity values for perrhenate and iodide were 25.6 +/- 1.4 and 106 +/- 3.2 pmol/ micro g, respectively, and corresponding affinity constant values were 4.06 +/- 0.87 and 24.6 +/- 1.81 micro mol/L. CONCLUSION: Perrhenate is avidly taken up by NIS in a manner similar to iodide and pertechnetate in vivo, with the exception of organification of iodide by the thyroid. By more fully appreciating the behavior of perrhenate, especially in relation to iodide and pertechnetate, we can better realize its potential role in the diagnosis and therapy of NIS-bearing tissues.

Animals↗
PubMed2003

Acute gastrointestinal bleeding.

Radionuclide bleeding scintigraphy remains a simple yet powerful method of localizing sites of gastrointestinal hemorrhage and is most commonly performed today using the red blood cell technique. Radionuclide techniques for detecting bleeding remain safe, sensitive, and noninvasive. Based on several simple concepts, including the use of cine-mode imaging over the abdomen, it is possible to achieve excellent accuracy in localizing the site of bleeding. Studies often contain additional ancillary information, which is helpful for diagnosis and patient treatment.

Acute Disease↗
PubMed2003

Selective role of nuclear medicine in evaluating the acute abdomen.

The imaging evaluation of the acute abdomen has clearly evolved with the introduction of high-resolution imaging techniques, such as CT, US, and MR imaging, leaving scintigraphic examinations an important, though selective, role based on their noninvasive, physiologic, and functional nature. Proper use of these examinations among all the diagnostic methods requires a good understanding of their strengths and limitations.

Abdomen, Acute↗
PubMed2002

Repeated bleeding scintigraphy may reveal that stationary foci of activity represent sites of active hemorrhage.

The goal of bleeding scintigraphy is to localize the site of origin of a hemorrhage to within general regions of the large or small bowel. Activity is typically seen to extravasate from the blood pool into the lumen, and the collection of activity then moves on sequential images, as a result of the cathartic action of blood. Sometimes, bleeding studies show a stationary focus of activity without subsequent movement. It is generally assumed that these foci represent fixed structures, such as the urinary tract or prominent vasculature, rather than acute extravasation of labeled blood into the bowel. The authors report three cases in which repeated studies showed that fixed foci of activity were, in fact, related to gastrointestinal bleeding. In two instances, the fixed foci represented extravasated blood that, for unexplained reasons, did not move during the study. In an additional case, the fixed activity visualized was ultimately shown to be prominent varices, which were implicated in the bleeding. Recognition of these possibilities, and consideration of possible strategies to localize the bleeding site further, should facilitate optimal patient treatment.

Aged↗
PubMed2002

Internet-based display of remotely-acquired ambient radiation data.

The World-Wide Web is a powerful medium for disseminating radiation information in a readily and universally retrievable manner. Ambient monitoring of radiation measurements at a New York City location (Jacobi Hospital, Bronx, NY 10461), with automated publication of the data on the Web, has been ongoing since 1998. Several times daily, specialized communications software automatically retrieves the data by modem to a central base computer from where it is uploaded to an Internet-accessible Web page. The data are then accessible by standard Internet Web browser at the address www.aw-el.com/nyc/. This automated acquisition and display system has run with uninterrupted operation and minimal operator intervention for over 3 years. As the Internet becomes a ubiquitous conduit for information transmittal, the Web can serve as an effective means of display for radiation data, with relevance to many health physics applications discussed herein.

Data Display↗