Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Technetium Compounds”

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 505 records · Page 28Linked to original sources
PubMed2002

Sentinel node mapping for colorectal cancer with radioactive tracer.

PURPOSE: The aim of this study was to test the feasibility and accuracy of radioactivity-guided mapping of the first lymph nodes found in draining the primary tumor site for colorectal cancer. METHODS: We enrolled 56 consecutive patients with preoperative diagnosis of curatively resectable colorectal cancer. Endoscopic injection of technetium Tc 99m-labeled tin colloid (15 MBq) was performed preoperatively, and radioactive sentinel nodes were identified intraoperatively with a gamma probe. Standard radical resection with lymph node dissection was performed in all patients, and all resected nodes were evaluated by routine histopathologic examination. RESULTS: Radioactivity-guided methods were used to detect sentinel nodes in 51 (91 percent) of 56 patients. The number of lymph nodes resected was 23.9 +/- 15.2 per case. The number of sentinel nodes was 3.5 +/- 2.1 (range, 0-8) per case. In 18 of 22 patients with lymph node metastasis, the sentinel node was positive. The incidence of metastasis in the sentinel node (22 percent) was significantly higher than that in nonsentinel nodes (3 percent, P < 0.01). Diagnostic accuracy according to sentinel node status was 92 percent (47/51). Four false-negative cases in this study were advanced cases with T3 primary tumors. The detection rate and diagnostic accuracy for patients with T1 or T2 primary tumors (29 cases) were 100 percent each. CONCLUSION: Intraoperative radioactivity-guided sentinel node mapping was accurate for patients with colorectal cancer with T1 or T2 tumors. The results suggest that sentinel node mapping and intraoperative biopsy may be a sensitive and specific diagnostic method for detecting metastasis in regional lymph nodes in patients with colorectal cancer.

Adult↗
PubMed2006

A preliminary study of the draining lymph node basin in advanced lower rectal cancer using a radioactive tracer.

PURPOSE: This study was designed to examine the draining lymph node basin at highest risk of metastasis in lower rectal cancer using 99 mTc-tin colloid. METHODS: In 43 patients, the area with highest hot nodes density was defined as the draining lymph node basin using a gamma probe. Metastatic states of all removed lymph nodes were examined histologically. RESULTS: A total of 203 hot nodes were identified in 39 patients (91 percent) with a mean of 5.2 nodes. The number of removed lymph nodes was 808 nodes: 670 nodes in the mesorectum, and 138 nodes in the pelvis. In 21 patients, the metastatic states of 119 nodes were investigated histologically. From the distribution of the identified hot nodes, the draining lymph node basins were classified into two patterns: lateral type (n = 17), and mesorectal type (n = 22). Only 20 (17 percent) of 119 positive nodes were identified as hot node. Tumor cells that occupied the lymph node diffusely or massively probably interfered with the exact diagnosis of metastasis. Lymph node metastasis in the pelvis was observed in 5 patients (13 percent). One false negative was of the mesorectal type with diffuse metastases in the para-aortic lymph nodes. The remaining four patients were of the lateral type and all positive lymph nodes, including positive nonhot nodes, were located within the draining lymph node basin. Consequently, in 20 (95.2 percent) of 21 patients with lymph node metastasis, all positive lymph nodes were located within the draining lymph node basin of the tumor. CONCLUSIONS: Two types of the draining lymph node basin of advanced lower rectal cancer were identified using this method. The concordance between lymph node metastases and the draining lymph node basin is good.

Female↗
PubMed2004

Mesojejunal lymph node metastasis in esophageal cancer following total gastrectomy.

We report on a case of thoracic esophageal cancer following total gastrectomy (rho-Roux-en-Y reconstruction) with metastasis to the mesojejunal lymph nodes. Subtotal esophagectomy with reconstruction using pedicled colon and dissection of two lymph node fields was performed. During the operation, we found three lymph nodes showing metastasis at the rho-Roux loop of the mesentery, and resected the rho-Roux loop. The route of the lymphatic drainage to the abdomen from the thoracic tumor seemed to have been changed by the prior gastrectomy. Based on the pathological findings, the case was diagnosed with T2N4M0, Stage IVa. We did not confirm that the distant metastases skipped the mesojejunal lymph nodes preoperatively; the distant metastases were detected accidentally by lymphoscintigraphy using technetium-99m tin colloid. We believe this case highlights the need for detailed examinations in esophageal cancer patients who have had prior gastrectomy.

Aged↗
PubMed1992

Chronic myocardial infarction: assessment of morphology, function, and perfusion by gradient echo magnetic resonance imaging and 99mTc-methoxyisobutyl-isonitrile SPECT.

To assess the ability of magnetic resonance imaging (MRI) to identify the anatomic and functional abnormalities associated with completely scarred myocardium, 20 patients with chronic transmural myocardial infarction confirmed by electrocardiography and cineventriculography were examined by gradient echo MRI. Myocardial perfusion at rest was assessed in corresponding transverse sections using 99mTc-methoxyisobutyl-isonitrile single-photon emission computed tomography (MIBI-SPECT). MRI scar was defined as diastolic wall thickness (DWT) 2.5 SD below corresponding normal values or systolic wall thickening (delta WT) less than or equal to 1 mm. For MIBI-SPECT images, scar was defined as a MIBI uptake less than 2.5 SD below normal values. By MIBI-SPECT, 152 segments contained normal tissue and 88 contained scarred myocardium. In 226 of 240 (94%) segments, MRI gradings by DWT and MIBI-SPECT gradings were identical. DWT by MRI was higher in normal than in scarred MIBI-SPECT segments (10 +/- 1 versus 4 +/- 2 mm, p less than 0.001). In 230 of 240 (96%) segments, MRI gradings by delta WT and MIBI-SPECT gradings were identical. Segments graded normal by MIBI-SPECT showed higher delta WT by MRI than scar segments (5 +/- 1 versus 0.3 +/- 1 mm, p less than 0.001). MIBI-SPECT perfusion defect size and regions with reduced DWT on MRI tomograms correlated well (r = 0.85). This study indicates that myocardial regions fulfilling electrocardiographic and ventriculographic criteria for transmural myocardial scar are clearly depicted by regional diastolic wall thinning and delta WT less than or equal to 1 mm on gradient echo MR images.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Redefinition of cutaneous lymphatic drainage with the use of lymphoscintigraphy for malignant melanoma.

Lymphoscintigraphy was performed on 82 patients with melanoma registered at the University Melanoma Clinic. From these data, precise lymphatic drainage basins could be drawn for the head, neck, shoulder, and trunk. These drawings differed significantly from the classic anatomic studies, providing a functional look at the cutaneous lymphatic drainage. This new method correlates much better with clinical experiences and demonstrates much larger areas of ambiguous drainage than previously reported. Data from the lymphoscintigrams also emphasize the individuality of cutaneous lymphatic flow. The implications of these data in planning elective node dissections for intermediate thickness melanomas are obvious, since it is estimated that up to 59% of the dissections for trunk and head and neck primary melanomas may be misdirected if based on classic anatomic studies. The data indicate that all patients with head, neck, and shoulder lesions should undergo lymphoscintigraphy to define possible drainage basins at risk for metastatic disease. Similarly, truncal lesions require scintigrams except when they are within four well-defined areas with an extremely low probability of ambiguous drainage. Lesions in these areas show very reliable and predictable drainage to a single nodal group.

Antimony↗
PubMed1983

The increase in vivo by electric currents of the 99mTc-methylene diphosphonate uptake and cyclic AMP content of the bone of the cat mandible.

Technetium-99-methylene diphosphonate (99mTc-MDP) bone images were obtained from live cats whose mandibles had been stimulated non-invasively and unilaterally with electric current (12 +/- 2 microA) for 1 week. The images were obtained using a gamma camera interfaced to a digital computer for quantitative comparison of the mandible. Radionuclide uptake by the stimulated sides increased by 59 +/- 26 per cent when compared with the contralateral control sites. Immunohistochemical staining of mandibular sections for adenosine 3',5'-monophosphate (cyclic AMP) showed that periosteal osteoblasts opposite the electrodes were intensely stained. Thus 99mTc-MDP scintigraphy is a sensitive non-invasive technique for determining in vivo enhanced bone remodelling activity. The immunohistochemistry indicates that the stimulation of bone cells was limited to surfaces adjacent to both cathode and anode.

Animals↗
PubMed1989

Toffee clearance and lingual sensory and motor activities in normal children and in children with articulation problems of speech.

The rate at which a standardized mouthful of toffee containing technetium (99mTc) tin colloid was cleared from the mouth during and after chewing was measured by counting the residual radioactivity in the mouth at short time intervals by external gamma counting. The clearance curve was resolved into three phases for each subject--chewing time (1), which coincided with the time to reach 10% of the initial counting rate, scavenging time (2), and a final slow diffusion phase (3). Although the mean chewing time was only 1.9 min, the technique allowed the pattern of clearance during this phase to be assessed for each of 10 normal children (mean age 11.1 yr) and 7 children (mean age 11.0 yr) diagnosed as having delayed articulation. Two measurements of sensory and motor functions of the tongue were made on the same subjects. These measurements were of oral stereognosis and tongue-tip manipulation. Within the control group, only the correlation between stereognosis error scores and the duration of phase 1 or phases 1 and 2 combined was statistically significant. The mean stereognosis and tongue manipulation scores were significantly lower in the poor articulation group than in normal children but, with one notable exception, the clearance curves were similar.

Adolescent↗
PubMed1996

Bile acid conjugation in early stage cholestatic liver disease before and during treatment with ursodeoxycholic acid.

The efficiency of bile acid conjugation before and during therapy with 600 mg/day of ursodeoxycholic acid was measured in seven adult patients with early chronic cholestatic liver disease (6 with primary biliary cirrhosis; 1 with primary sclerosing cholangitis). Duodenal bile samples were obtained by aspiration and the proportion of unconjugated bile acids was determined using lipophilic anion exchange chromatography to separate bile acid classes, followed by analysis of individual bile acids by gas chromatography-mass spectrometry. The proportion of conjugated bile acids was determined by high-performance liquid chromatography. Use of a (99m)Tc-HIDA recovery marker permitted the absolute mass of unconjugated bile acids in the gallbladder to be calculated. Unconjugated bile acids comprised 0.4% of total biliary bile acids before and 0.2% during ursodeoxycholic acid therapy, indicating highly efficient conjugation of bile acids. During therapy, percentage unconjugated ursodeoxycholic acid significantly increased from (mean +/- S.D.) 13 +/- 13% to 54 +/- 12%; P < 0.002. When the unconjugated and conjugated fractions of bile acids were compared, there was an enrichment in unconjugated fraction for cholic acid and ursodeoxycholic acid and a depletion for chenodeoxycholic acid both in basal condition and during ursodeoxycholic acid therapy, suggesting that hydrophilic bile acids were conjugated less efficiently. During therapy, the conjugation efficiency significantly increased for cholic acid and ursodeoxycholic acid. The pretreatment mass of total unconjugated bile acids in the gallbladder was (mean +/- S.D.) 4.4 +/- 3.2 mumol, and was not significantly changed by ursodeoxycholic acid therapy (6.2 +/- 3.5 mumol). However, ursodeoxycholic acid therapy caused a significant increase in the mass of unconjugated ursodeoxycholic acid. It is concluded that endogenous bile acids and exogenous ursodeoxycholic acid when given at the usual dose are efficiently conjugated in patients with early cholestatic liver disease. Despite showing increased biliary unconjugated ursodeoxycholic acid during its oral administration, our data do not lend support to the occurrence of hypercholeresis due to cholehepatic shunting of bile acids.

Adult↗
PubMed1986

Interobserver variation in the detection of metastases on liver scans.

Two specialists in nuclear medicine and two trainees independently read 106 liver scans for abnormalities suggestive of metastases. The four observers made a positive diagnosis with a significantly different frequency. The overall agreement between pairs of observers was 0.83-0.87. After adjusting for the expected chance agreement, kappa-values between 0.66 and 0.74 were obtained. No difference was found in the level of agreement between the two specialists or between the two trainees. After a consensus conference where the observers tried to unify their diagnostic interpretation, another 106 scans were read for abnormalities suggestive of metastases. The conference did not increase the level of agreement. Scintigraphic lesions that especially imply a risk of disagreement are pointed out.

Colloids↗
PubMed1982

The 99Tcm-Sn-polyphosphate scintimetric time course of human tibial fractures with delayed union or pseudarthrosis.

In 17 fractures of the human tibia, showing delayed union or the development of pseudarthrosis, the amount of callus formed was assessed monthly by scintimetry following intravenous administration of 99Tcm-Sn-polyphosphate. The mean scintimetric time course of the group of fractures with the atrophic type of delayed union was statistically significantly lower between the fourth and fourteenth week than that of fractures with uncomplicated healing. Nearly two-thirds of the fractures showed scintimetric ratios below the lower normal confidence limit (2 s.d.). The mean scintimetric time course of the fractures with the hypertrophic type of delayed union showed a normal scintimetric time course up to the eighth week, but from the tenth week a statistically significantly higher scintimetric ratio than the fractures with uncomplicated healing was found. The scintimetric ratio after the fourteenth week was below 2.5 for fractures with the atrophic type of delayed union, and above 2.5 for fractures with the hypertrophic type. The scintimetric time course of fractures which developed pseudarthroses was not different from those showing delayed union. The scintimetric method allows early detection of a pathological course of fracture healing. It supplies information about the functional state of the healing process and serves as an indicator of the correct treatment.

Adolescent↗
PubMed1982

Ytterbium-169-phytate: a potential new radiopharmaceutical for functional scintigraphy of the liver.

A new radiopharmaceutical for liver scintigraphy has been prepared by reacting 169YbOCl with Na phytate under conditions which yield a labelling efficiency of more than 99% over a wide pH range. In rabbits the resultant colloidal preparation shows a rapid elimination from the blood and high initial uptake in liver. Subsequently about 90% of the liver activity is lost within 3 days, the remainder being eliminated more slowly. The radiopharmaceutical is non-toxic and has a shelf-life of about 3 months. Scintigrams obtained in patients with hepatomegaly suggest that this new agent gives better visualization of space occupying lesions of the liver than 99mTc-Sn colloid. The radiation dose to the patient from this agent is low and comparable with that from other radiopharmaceuticals used for liver scintigraphy.

Adult↗
PubMed1983

Stability of the radiopharmaceutical [99mTc]DMSA: study of the ligand exchange reaction with [99Tc]EDTA.

A kinetic study was made of the ligand exchange reaction between [99mTc]EDTA and DMSA. The results of this study indicate that this exchange reaction is closely related to temperature and pH. Kinetic and thermodynamic parameters demonstrate that both complexes--[99MTc]EDTA and [99mTc]DMSA--have a similar stability. Furthermore, the existence of an acid-basic catalysis for the global exchange reaction was established, and the catalytic parameters were calculated. These data were obtained by radiochromatography and visible spectrophotometry.

Drug Stability↗
PubMed1985

A convenient method for the preparation of 99mTc(V)dimercaptosuccinic acid (99mTc(V)-DMSA).

Tc(IV)-DMSA for kidney scintigraphy has been prepared in acidic solution. Once the labeling is done in basic solution, upon addition of a small amount of NaHCO3, a mixture of 3-4 other DMSA-complexes is formed, presumably containing Tc(V). Kidney uptake in male adult rats of the 99mTc(V)-DMSA is 1.6% injected dose/g (4.9%/total organ) compared to 16.4% injected dose/g (resp. 50.3%/total organ) for 99mTc(IV)-DMSA.

Animals↗
PubMed1985

Bone scanning with 99mtechnetium phosphate to assess condylar hyperplasia. Report of two cases.

Condylar hyperplasia poses a problem in planning treatment because it is a self-limiting process for some but not all patients. Continued growth creates a progressive deformity that requires condylectomy, whereas an enlarged condyle can be left in place after hyperplastic growth ceases, even if ramus surgery is needed to correct asymmetry. Bone scan with 99mtechnetium phosphate can be used to assist in making the differential diagnosis. In the two patients reported here, abnormal metabolic activity revealed by bone scans supported clinical and historical evidence that the condylar hyperplasia was active and required surgical correction, including condylectomy. The two cases demonstrate different approaches to postsurgical orthodontic treatment, depending on the amount of normal growth expected.

Adolescent↗