Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “TECHNETIUM”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMed1997

Comparison of technetium-99m-ll-EC isomers in rats and humans.

UNLABELLED: Technetium-99m-L,L-ethylenedicysteine (99mTc-LL-EC) is a new renal imaging agent with pharmacokinetic properties reported to be slightly superior to those of 99mTc-mercaptoacetyltriglycine (99mTc-MAG3); however, to better define the potential of the enantiomer 99mTc-DD-EC and the diastereomer 99mTc-DL-EC as renal imaging agents, we compared the three EC stereoisomers with 131I-orthoiodohippurate (OIH) in a series of rats and humans. METHODS: Each 99mTc-EC stereoisomer was coinjected with OIH in six Sprague-Dawley rats for measurements of clearance and extraction fraction. Each stereoisomer was also coinjected with OIH in three human volunteers followed by sequential imaging, plasma clearance measurements and timed urine collections. RESULTS: Technetium-99m-DD-EC had the highest clearance and extraction efficiency in rats (p < or = 0.02). In humans, image quality was good with all three agents. The clearance ratio (EC/OIH) was 82% +/- 8% for 99mTc-DD-EC compared to 70% +/- 3% and 40% +/- 5% for 99mTc-LL-EC and 99mTc-DL-EC, respectively. Technetium-99m-DD and 99mTc-LL-EC were excreted more rapidly than 99mTc-DL-EC. CONCLUSION: Technetium-99m-DD-EC has excellent imaging properties and the data suggest that its clearance may approach that of OIH more closely than any other 99mTc renal agent. A potential limitation is the fact that both 99mTc-DD and LL-EC exist in dianionic (80%) and monoanionic (20%) forms at physiological pH and it is unlikely that these two forms have the same clearance or protein binding affinity.

Animals↗
PubMed1998

Technetium-99m-tetrofosmin scintigraphy in pulmonary tuberculosis.

UNLABELLED: Technetium-99m-tetrofosmin, an agent that is widely used in myocardial imaging, has been reported to accumulate in several types of malignancies, including lung tumors. Yet, there is limited knowledge about its role in imaging infection or inflammatory lesions. The aim of this study was to investigate the role of 99mTc-tetrofosmin scintigraphy in pulmonary tuberculosis in cases with active and inactive tuberculosis in comparison with radiological and microbiological findings. METHODS: Twenty-seven patients with active pulmonary tuberculosis (APTB) and 6 patients with inactive pulmonary tuberculosis (IPTB), proven by sputum smears and cultures, were included in this study. Mean age of the group was 42.6+/-13 yr. Nine months after therapy, 99mTc-tetrofosmin scintigraphy was repeated in 6 patients with APTB to evaluate response to therapy. Ten-minute anterior and posterior chest images were acquired 20 and 60 min after the injection of 370 MBq (10 mCi) 99mTc-tetrofosmin. The images were evaluated both visually and semiquantitatively by two blinded nuclear medicine physicians. For semiquantitative evaluation, regions of interest (ROIs) were drawn over the lesion (L) and nonlesion areas (NL). The mean count values of ROIs were obtained and L/NL ratios were calculated. RESULTS: According to the visual evaluations, 99mTc-tetrofosmin uptake was Grade (+) in 4 (15%) and Grade (++) in 23 (85%) patients with APTB. Technetium-99m-tetrofosmin uptake was negative in 5 patients with IPTB. Grade (+) 99mTc-tetrofosmin uptake was observed in only one inactive case. After therapy, there was no 99mTc-tetrofosmin uptake in 3 patients, which correlated well with chest radiography and clinical findings. In the other 2 patients, 99mTc-tetrofosmin uptake was slightly decreased when compared with a previous scan that correlated with radiological and clinical findings. In 1 patient with bilateral lung disease, 99mTc-tetrofosmin uptake decreased on the right lung lesions, whereas the left lung lesions persisted with no change. The mean early and delayed L/NL ratios of APTB were 1.53+/-0.22 and 1.45+/-0.21, respectively. Although 99mTc-tetrofosmin uptake in APTB lesions was more visually marked in early images than that in delayed images, there was no statistically significant difference between these two sets of images. CONCLUSION: Technetium-99m-tetrofosmin scintigraphy showed increased uptake in APTB lesions related to disease activity. After treatment, 99mTc-tetrofosmin uptake disappeared or decreased, correlating well with radiological and clinical findings. Technetium-99m-tetrofosmin scintigraphy may have a complementary role in the assessment of APTB as well as in follow-up treatment.

Adolescent↗
PubMedDate not supplied

Contribution of electrospray mass spectrometry for the characterization, design, and development of nitrido technetium and rhenium heterocomplexes as potential radiopharmaceuticals.

Diagnostic nuclear medicine (NM) is among the imaging procedures (together with X-ray, computerized tomography, magnetic resonance, and echography) the clinicians can routinely adopt to image organs or tissues and related disorders. (99m)Tc-based agents are the radiopharmaceuticals of election in diagnostic NM because of the ideal physical properties of the 99mTc nuclide (t1/2 6.01 hr; Egamma 142 keV), low cost, and easy availability through the commercial 99Mo/99mTc generator, and chemical versatility of the element. In the last two decades the synergistic work of clinics, pharmacologists, and coordination chemists has had a tremendous impact in the development of new 99mTc-based radiopharmaceuticals through the recognition of the structure at the molecular level of the agent utilized. This has been achieved by studying the physico-chemical properties of the long-lived 99gTc (t1/2 2.11 x 10(5) year; Ebeta 292 keV) and third-row congener Re isostructural compounds. Electrospray ionization mass spectrometry (ESI-MS) and collision experiments (MS/MS) represent valuable analytical techniques suitable for the characterization of both technetium and rhenium complexes relevant to NM. Unequivocal structural identification of these bioinorganic compounds, either simple coordination complexes ("essential radiopharmaceuticals") or more sophisticated structures carrying bioactive fragments ("receptor-specific" radiopharmaceuticals), can be realized in combination with multinuclear NMR spectroscopy. MS/MS experiments provide useful information on the different metal-ligand bond strength, and comparison of the fragmentation profiles of isostructural technetium and rhenium compounds give additional details on the role played by the metal in determining preferred decomposition channels. The analysis of these data contribute to design novel synthetic strategies for the obtainment of technetium and rhenium compounds relevant to NM. The chemistry underlying the production of a new class of potential radiopharmaceuticals including a terminal nitrogen bond and a mixed coordination sphere comprising heterodiphosphines and/or dithiocarbamates (DTC) is presented in detail together with the ESI-MS and MS/MS investigations.

Animals↗
PubMed1988

Significance of technetium-99m/thallium-201 overlap on simultaneous dual emission computed tomography in acute myocardial infarction.

To examine the significance of technetium-99m pyrophosphate/thallium-201 scintigraphic overlap as an indicator of identifying early coronary reperfusion (less than or equal to 3 hours), 32 patients, in whom coronary recanalization was attempted for acute myocardial infarction (AMI), underwent myocardial imaging 3 days after the onset of AMI. The imaging was performed by simultaneous dual emission computed tomography, which allows simultaneous recording of technetium-99m pyrophosphate and thallium-201 images and comparison between both images in the same slice. The patients were separated into 3 groups: 9 patients in whom reperfusion was successful and showed scintigraphic overlap (group A), 12 with successful recanalization but no overlap (group B) and 11 with neither coronary reflow nor overlap (group C). No patient in whom reperfusion failed showed scintigraphic overlap (p less than 0.05). Groups A and B were comparable in age, infarct vessel, collateral circulation, residual coronary stenosis and cumulative release of creatine kinase-MB isoenzyme. However, compared with group B, group A had a shorter interval between onset of AMi and reflow (2.5 +/- 0.8 vs 4.8 +/- 1.3 hours, p less than 0.001). The presence of scintigraphic overlap identified early coronary reflow with a sensitivity of 80%, specificity of 91%, positive predictive accuracy of 89% and negative predictive accuracy of 83%. Thus, technetium-99m/thallium-201 overlap on dual emission computed tomography can be used as an index of documenting early recanalization and might reflect the presence of salvaged myocardium adjacent to the necrotic tissue.

Clinical Enzyme Tests↗
PubMed1983

Evaluation of technetium-99m phosphate imaging for predicting skin ulcer healing.

We have developed criteria for radionuclide angiography to assess skin ulcer perfusion as an indicator of healing capacity. Twenty-six studies were performed on 21 consecutive patients with nonhealing ulcers of the lower leg; 20 mCi of technetium-99m phosphate was injected intravenously with immediate sequential scintillation camera imaging of the ulcer and surrounding area at 2 second intervals, followed by blood pool and delayed static images. Two radiologists without clinical bias graded the perfusion to the ulcer on the images as normal, increased, or reduced with respect to the opposite limb. Patients were either followed as outpatients for more than 10 days, as inpatients for at least 10 days, or both to determine whether ulcers showed clinical evidence of wound healing with optimal outpatient and in-hospital care. Of the 17 patients whose ulcers healed, imaging with technetium-99m phosphate predicted the outcome in 16. In nine patients the ulcers did not heal. This was correctly predicted by technetium-99m phosphate in eight of the patients. Overall, the sensitivity was 94 percent and the specificity was 89 percent. This technique appears to be a simple, reliable way to predict the microcirculatory adequacy for ulcer healing.

Diphosphates↗
PubMed1988

Recovery of left ventricular function after myocardial infarction can be predicted immediately after thrombolysis by semiquantitative intracoronary thallium and technetium pyrophosphate scintigraphy.

The accuracy with which intracoronary thallium and technetium pyrophosphate scintigraphy during intracoronary thrombolysis predicts myocardial salvage was studied in 58 patients with acute myocardial infarction by comparing the acute scintigraphic findings with subsequent left ventricular function. Scintigrams obtained before and immediately after thrombolysis were interpreted by three independent observers using a scoring system. Regional wall motion in the infarct area was determined from left ventricular (LV) cine angiograms using the center-line method. Patients with mild hypokinesis (hypokinesis less than or equal to -2 SD from normal) could be distinguished from those with severe hypokinesis (hypokinesis greater than -2 SD) using the prethrombolysis thallium score with an accuracy of 83%. Accuracy using the post-thrombolysis score was 76%. When the post-thrombolysis thallium and technetium pyrophosphate scores were combined, differentiation was possible in 91% of all patients studied, and in 100% of patients with anterior myocardial infarction. Thus, analysis of combined thallium and technetium pyrophosphate scintigraphy accurately predicts recovery of LV function after thrombolysis and may be helpful in deciding whether acute percutaneous transluminal coronary angioplasty or bypass surgery should be performed after thrombolysis.

Cardiac Output↗
PubMed1984

Non-invasive assessment of the presence and severity of cardiac amyloidosis. A study in familial amyloidosis with polyneuropathy by cross sectional echocardiography and technetium-99m pyrophosphate scintigraphy.

Twelve patients with familial amyloidosis with polyneuropathy were examined both by cross sectional echocardiography and by technetium-99m pyrophosphate scintigraphy to assess involvement of the heart non-invasively. All 12 patients had echocardiographic abnormalities. The most prominent findings were highly refractile myocardial echoes, thickened heart valves, and increased thickness of the heart walls. Four patients had abnormal myocardial uptake of technetium-99m pyrophosphate. The remaining eight had equivocal or no myocardial uptake and were considered to have normal scintigrams. A certain amount of amyloid is probably required to produce an abnormal scintigram, although lesions with less amyloid can evidently be identified by echocardiography. Neither the duration of polyneuropathy nor its severity showed any relation to the echocardiographic or scintigraphic findings. It is concluded that cross sectional echocardiography is superior to technetium-99m pyrophosphate scintigraphy in detecting cardiac involvement in familial amyloidosis with polyneuropathy and that these results may also be applicable to other forms of amyloidosis.

Adult↗
PubMed2000

Hyperthermia increases accumulation of technetium-99m-labeled liposomes in feline sarcomas.

The effect of hyperthermia on the accumulation of technetium-99m-labeled liposomes was studied in feline sarcomas. Each cat received two separate injections of liposomes. The first was used to quantify the amount of technetium-99m-labeled liposomes within the tumor under normothermic conditions. The second injection was made at the beginning of a 60-min hyperthermia procedure. Planar scintigraphy was used to measure the activity of technetium-99m-labeled liposomes within the tumor at predetermined times up to 18 h after injection. Regions of interest were drawn for the tumor, lungs, liver, kidney, and aorta. Counts in the regions of interest were decay corrected. Counts/pixel in the tumor under normothermic and hyperthermic conditions were normalized to aorta counts/pixel. A total of 16 cats were eligible for the study. In two of the 16 cats, incomplete count data precluded analysis. In the remaining 14 cats, hyperthermia resulted in a significant increase in liposome accumulation in the tumor (P = 0.001). Tumor volume ranged from 1.2 to 236.2 cm3, and thermal dose ranged from 2.0 to 243.3 CEM43CT90 (equivalent time that the 10th percentile temperature was equal to 43 degrees C). There was not a relationship between either tumor volume or hyperthermia dose on the magnitude of increased liposome accumulation, suggesting that this method has application across a range of tumor volumes and degrees of heatibility.

Animals↗
PubMed1986

[Early noninvasive detection of reperfusion and infarct by intravenous technetium 99m pyrophosphate scintigraphy following thrombolysis].

To determine whether technetium-99-pyrophosphate accumulation immediately after intravenous thrombolysis can serve as a marker of reperfusion and infarct size, 17 patients with acute myocardial infarction were studied. Immediately after thrombolysis 10 mCi of technetium-99m pyrophosphate were injected intravenously. Coronary and left ventricular angiography were then performed in all patients, revealing patent coronary arteries in 13 patients. In all patients, 0.3 and 0.5 mCi of thallium-201 were injected into the right and left coronary artery, respectively, followed by planar scintigraphy. 6 patients with patent coronary arteries and a large thallium-201 defect had massive (more than one third of the cardiac silhouette) pyrophosphate accumulation (group A), whereas 7 patients with a small or no thallium-201 defect in the presence of a patent infarct artery had either focal or no pyrophosphate accumulation (group B). In contrast, 4 patients with an occluded infarct artery showed no acute pyrophosphate uptake despite a large thallium-201 defect (group C). Emission computed tomography confirmed the planar scintigraphic data in group A patients and revealed small thallium-201 defects and focal pyrophosphate accumulation in group B patients with negative planar scintigrams. Global and regional ejection fractions in the infarct area, measured from the acute and follow-up left ventricular angiograms, were higher in group A than in group B and C patients. It is concluded that early intravenous technetium-99m pyrophosphate scintigraphy in patients with acute myocardial infarction undergoing intravenous thrombolysis may serve as an indicator of reperfusion and infarct size.

Adult↗
PubMed1986

Technetium-99m-d, 1-HM-PAO: a new radiopharmaceutical for imaging regional brain perfusion using SPECT--a comparison with iodine-123 HIPDM.

A new radiopharmaceutical, technetium-99m hexamethylpropyleneamine oxime (99mTc-d, 1-HM-PAO), has been reported to cross the blood-brain-barrier and to distribute in brain in proportion to regional blood flow. This study reports brain imaging obtained with 99mTc-d,1 HM-PAO in 20 subjects; seven without evidence of cerebral disease and 13 with cerebrovascular disorders. In 16 patients comparative data were available with N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamine ([123I]HIPDM). Technetium-99m-d, 1-HM-PAO is retained sufficiently long to allow single photon emission computed tomography (SPECT) with widely available rotating gamma camera systems. The kinetics demonstrated a rapid brain uptake and prolonged retention of activity in cerebral structures. Good tomographic images are obtained with much higher uptake in gray than in white matter. Blood flow maps are comparable to those achieved with [123I]HIPDM and established strokes were clearly seen, with similar details as in HIPDM studies. Delayed studies showed that the distribution in the brain remained virtually unchanged. Technetium-99m-d, 1-HM-PAO imaging appears particularly promising in routine examination of patients with cerebrovascular disorders.

Brain↗
PubMed1983

[A critical study of technetium 99m and xenon 133 lung scintigraphy in patients with cystic fibrosis].

During investigations for cystic fibrosis, 41 children, most of whom were aged 0 to 7 years, were submitted to lung scintigraphy with technetium 99m first and xenon 133 subsequently. This procedure ensured accurate location of pulmonary lesions. The reliability of the radio-isotopic study was assessed through comparison to conventional clinical and radiological criteria, arterial blood gas determinations and pulmonary function tests. Perfusion scintigraphy with technetium 99m labelled macroaggregated albumin (n = 90) was compared to functional parametrical xenon, 133 study (n = 25) (perfusion-ventilation). The degree of lung disease was evaluated during serial examinations in order to improve prognostic prediction. Technetium 99m scintigraphy proves a reliable and sensitive procedure which accurately reflects the patients' clinical status when it is performed in the absence of patent pulmonary superinfection. Xenon 133 scintigraphy, which is more difficult to perform and interpret, has the advantage of providing a topographic and quantitative evaluation of pulmonary blood flow and ventilatory efficiency.

Adolescent↗
PubMed1983

Post-traumatic avascular necrosis of the femoral head predicted by preoperative technetium-99m antimony-colloid scan. An experimental and clinical study.

We used technetium-99m antimony colloid to visualize the bone marrow of the head of the femur within twenty-four hours after interruption of the blood supply by subcapital osteotomy and section of the ligamentum teres in thirteen rabbits and within twenty-four hours after a subcapital fracture in thirty patients. Of the rabbits, all showed loss of marrow radioactivity over the affected femoral head. Bone-imaging with technetium-99m methylene diphosphonate, in contrast, failed to demonstrate any abnormality in the avascular head of the femur for as long as forty-eight hours after osteotomy. This difference between the marrow scan and the bone scan was attributed to earlier loss of function in the marrow cells than in the osteocytes. The thirty patients who had a preoperative scan within twenty-four hours after sustaining a subcapital fracture were treated by internal fixation with a Richards screw and plate and were followed for as long as two years, or until the patient died or radiographs showed evidence of avascular necrosis. The preoperative technetium-99m antimony-colloid activity in the head of the fractured femur was normal in sixteen patients and absent in fourteen; two of the fourteen had no activity in either hip, which precluded assessment of the fractured hip in these patients. In fifteen of the sixteen hips, preservation of the uptake in the marrow of the head of the fractured femur preoperatively predicted normal healing. Late segmental collapse developed in the remaining hip. In eleven of the twelve patients who had loss of marrow activity in the femoral head preoperatively, avascular necrosis developed within two years. One patient was asymptomatic at two years, with no evidence of necrosis. The two patients who had no marrow activity in either hip both had avascular necrosis within one year after surgery.

Aged↗
PubMed1981

The use of technetium-99m sulfur colloid as a marker for experimental venous thrombosis: concise communication.

The binding of technetium-99m sulfur colloid to in vivo thrombi was studied in a rat model of deep vein thrombosis. After thrombosis was induced by mechanical traumatization of a right femoral vein segment, technetium-99m sulfur colloid was injected into the peripheral veins of different experimental groups at intervals of 30 min and 1-7 days. Ratios of mean activity in traumatized right femoral vein segment to activity in control segments of left femoral vein (R/L ratios) ranged form 2.97-11.0 for all in situ venous thrombi studied. There was no relation between clot size and R/L ratios. The significant uptake ratios observed by us for venous thrombi up to 1 wk in age suggest that in vivo thrombus detection may be feasible by imaging with a gamma camera after technetium-99m sulfur colloid injection in a peripheral vein.

Animals↗
PubMed1993

Quantitative assessment of hepatocellular function through in vivo radioreceptor imaging with technetium 99m galactosyl human serum albumin.

Technetium 99m diethylenetriaminepentaacetic acid-galactosyl human serum albumin is a newly developed analog ligand to asialoglycoprotein receptor, which is a hepatic cell surface receptor specific for galactose-terminated glycoproteins. Hepatic functional imaging, which yields estimates of asialoglycoprotein receptor concentration, was performed after intravenous injection of 3 mg technetium 99m diethylenetriaminepentaacetic acid-galactosyl human serum albumin. A total of 75 human subjects were studied: 6 controls without liver diseases, 51 patients with chronic liver diseases and 18 patients with acute liver diseases. In chronic liver disease the asialoglycoprotein receptor concentration significantly correlated with the clinical severity based on the criteria of the Liver Cancer Study Group of Japan (rs = -0.890, p = 0.0001). Good correlations between the asialoglycoprotein receptor concentration and conventional liver function tests were also observed. In acute liver disease the asialoglycoprotein receptor concentration correlated well with the normotest (r = 0.796, p = 0.0001), prothrombin time (r = 0.701, p = 0.0002) and total serum bilirubin (r = -0.642, p = 0.0007). We conclude that the parameter, asialoglycoprotein receptor concentration, obtained from the kinetic analysis of technetium 99m diethylenetriaminepentaacetic acid-galactosyl human serum albumin time-activity data, is a sensitive measure of functioning hepatocyte mass in acute and chronic liver disease.

Acute Disease↗
PubMed1994

Radioimmunodetection of non-small cell lung cancer using technetium-99m-anticarcinoembryonic antigen IMMU-4 Fab' fragment. Preliminary results.

BACKGROUND: Although computed tomography and magnetic resonance imaging have improved the staging and evaluation of non-small cell lung cancer (NSCLC), mediastinal staging lacks adequate specificity and sensitivity. Radioimmunodetection may augment computed tomography and magnetic resonance imaging. The authors evaluated the ability of the technetium 99m-anticarcinoembryonic antigen IMMU-4 Fab' fragment to localize NSCLC in vivo, measured its pharmacokinetics, and estimated its radiation dose. METHODS: Seventeen patients with carcinoembryonic antigen-positive NSCLC received 16-30 mCi of technetium 99m IMMU-4 Fab'. Planar imaging was performed at 1-7 hours and 20-24 hours. Single-photon emission computed tomography (SPECT) was performed within 8 hours after injection. In 10 patients, blood sampling, urine collection, and quantitative imaging were performed to determine blood and urine pharmacokinetics and radiation dose estimates. Human anti-mouse antibody response was measured for as long as 3 months after administration. RESULTS: Planar and/or SPECT imaging detected 72% of 32 known lesions. SPECT was more sensitive than planar imaging. T1/2 alpha averaged 0.18 +/- 0.33 hours; T1/2 beta averaged 8.02 +/- 5.53 hours. The mean concentration versus time value was 1.11 +/- 0.56 mg.h. The average whole body dose estimated for administration of 30 mCi was 0.45 +/- 0.08 rads. No human anti-mouse antibody responses were detected. CONCLUSION: The tumor detection rate was high, but the persistent blood pool at < 8 hours complicated image interpretation. An intermediate imaging time point (12-16 hours) might be preferable. SPECT is an important adjunct to imaging with this radioimmunoconjugate. The acceptable dosimetry estimated for 30 mCi Technetium 99m IMMU-4 Fab' and the lack of human anti-mouse antibody responses suggest this is a promising localizing tool for NSCLC:

Antibodies, Monoclonal↗
PubMed1993

Usefulness of technetium-99m hydroxymethylene diphosphonate scans in localizing bone metastases of differentiated thyroid carcinoma.

Iodine-131 is uniquely able to demonstrate iodine uptake of differentiated thyroid carcinoma (DTC), but precise localization may be difficult, especially in the thorax, due to the quality of image resolution with 131I and the lack of anatomical landmarks. When bone metastases do not show radioiodine uptake bone scintigraphy can be used to detect them. We studied two groups of patients. In group 1, 15 patients with known bone metastases of DTC were treated with 3.7 GBq 131I. After 4 or 5 days, technetium-99m hydroxymethylene diphosphonate (HMDP; 740 MBq) was injected and a whole-body scan with simultaneous acquisition of 131I and 99mTc-HMDP images was carried out using a large field of view gamma camera fitted with a high-energy collimator. Technetium uptake was abnormal in 47 of 63 localizations, being increased in 29 foci, decreased in 7 and heterogeneous in 11. The superimposition of 131I and 99mTc-HMDP scans permitted an accurate localization in 80% of spine metastases and in 46% of osseous thoracic localizations, even in the presence of lung metastases. In group 2, 9 patients, who had bone pain, neurological signs or elevated serum thyroglobulin, had DTC bone metastases without iodine uptake. They received a diagnostic dose of 99mTc-HMDP 3h prior to scintigraphy with a large field of view gamma camera fitted with a low-energy collimator. Technetium uptake was abnormal in 37 of 38 localizations, being increased in 34 foci and decreased in 3. One false-negative was found in a skull metastasis. In both groups of patients, 99mTc-HMDP scans were useful.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma, Follicular↗
PubMed1991

Monoclonal antibody BW431/26 labelled with technetium 99m and indium 111: an investigation of the biodistribution and the dosimetry in patients.

As a competitive diagnostic tool for the detection of malignant tumours and other pathological conditions, monoclonal antibodies have long been established. Herein we give the biokinetic data of the antibody BW 431/26 and the consequent radiation dose to patients. These parameters were recorded in 39 patients, using the antibody labelled either with technetium 99m or indium 111. Remarkable differences were observed between the two radionuclides. Whereas the indium-labelled one showed biexponential elimination kinetics, the technetium-labelled one is eliminated linearly over time. The distribution pattern of the two is identical, although the radiation dose varies quite a lot, being 20-fold higher with indium 111 when total body exposure is taken into account (for 111In the whole-body radiation exposure is 0.1 mGy/MBq; for 99mTc it is 0.0047 mGy/MBq). With respect to these results and considering the general availability of the technetium-labelled Ab, it is the best choice for diagnostic use.

Humans↗
PubMed1991

Indium-111 myosin-specific antibodies and technetium-99m pyrophosphate in the detection of acute cardiac rejection of transplanted hearts: studies in a heterotopic rat heart model.

111In-labelled myosin-specific antibodies were evaluated as an indicator of early changes in acute rejection in a rat heart heterotopic transplant model. Uptake of antibodies was measured in allograft and isograft hearts of animals undergoing different regimens of cyclosporine treatment and compared with the uptake of technetium-99m pyrophosphate. The data were correlated with histological estimation of the severity of myocyte necrosis and signs of early rejection (venous cuffing and endocardial inflammation, indicators of perivascular infiltrate and intermyocyte extension, respectively). Myocyte necrosis in transplanted hearts was reflected by increases in technetium-99m pyrophosphate accumulation (r = 0.88) but was poorly correlated with labelled antibody uptake (r = 0.58). There was no positive correlation between the degree of early cardiac rejection and uptake of either of the radiopharmaceuticals: accumulation of the labelled antibodies paradoxically declined with increased histological severity scores, whereas that of technetium-99m pyrophosphate remained unchanged. Cyclosporine treatment augmented the uptake of labelled antibodies in transplanted hearts. This may be due to alterations in plasma membrane permeability brought about by the drug, resulting in a rise in antibody binding to intracellular myosin.

Animals↗