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 1,459 records · Page 81Linked to original sources
PubMed2002

Evaluation of active bleeding into hematomas by technetium-99m red blood cell scintigraphy before angiography.

PURPOSE: To evaluate the utility of technetium-99m red blood cell (Tc-99m RBC) scintigraphy in the diagnosis of active hemorrhage into large intra-abdominal hematomas before arteriography. METHODS: This retrospective case series describes four patients (1 man and 3 women) with large abdominal wall and retroperitoneal hematomas confirmed by computed tomography who underwent Tc-99m RBC scintigraphy before angiography. Arterial transcatheter embolization was performed if active hemorrhage was found. RESULTS: Three of the patients had positive findings on Tc-99m RBC scans, which showed spreading of the labeled erythrocytes into the hematoma space. Positive scintigraphy was diagnostic for active hemorrhage and helped localize the bleeding sites. Angiography confirmed the diagnosis in all patients with positive scintigraphy and ruled out active bleeding in the patient with a negative Tc-99m-labeled RBC scan. CONCLUSION: Tc-99m RBC scintigraphy appears to be sensitive and accurate in detecting active hemorrhage into intra-abdominal hematomas.

Abdominal Wall↗
PubMed1989

Technetium-99 cycling in maple trees: characterization of changes in chemical form.

Prior field studies near an old radioactive waste disposal site at Oak Ridge, TN, indicated that following root uptake, metabolism by deciduous trees rendered 99Tc less biogeochemically mobile than expected, based on chemistry of the pertechnetate (TcO-4) anion. Subsequently, the form of technetium (Tc) in maple tree (Acer sp.) sap, leaves, wood and forest leaf litter was characterized using one or more of the following methods: dialysis, physical fractionation, chemical extraction, gel permeation chromatography, enzymatic extraction, or thin layer chromatography (TLC) on silica gel. Chromatography (Sephadex G-25) of TcO-4 incubated in vitro with tree sap showed it to behave similar to TcO-4 anion. When labeled wood and leaf tissues were processed using a tissue homogenizer, 15% and 40%, respectively, of the Tc was solubilized into phosphate buffer. Most (65% to 80%) of the solubilized Tc passing a 0.45-micron filter also passed through an ultrafiltration membrane with a nominal molecular weight cutoff of 10,000 atomic mass units (amu). A majority (72% to 80%) of the Tc in wood could be chemically removed by successive extractions with ethanol, water and weak mineral acid. These same extractants removed only 23% to 31% of the Tc from maple leaves or forest floor leaf litter. Most of the Tc in leaves and leaf litter was removed only by strongly alkaline reagents typically used to release structural polysaccharides (hemicelluloses) from plant tissues. Chromatography (Sephadex G-25) of the ethanol-water extract from wood and the alkaline extract from leaves demonstrated that Tc in these extracts was not principally TcO-4 but was complexed with molecules greater than 1000 amu. Incubations of leaf and wood homogenates with protease approximately doubled the amount of Tc released from contaminated tissues. Ultrafiltration of protease-solubilized Tc from leaves and wood showed that 40% and 93%, respectively, of the Tc was less than 10,000 amu. TLC of the less than 10,000 amu fraction indicated the presence of TcO-4 in wood but not in leaves. In the leaf, TcO-4 is converted to less soluble forms apparently associated with structural components of leaf cell walls. This conversion explains why 99Tc is not easily leached by rainfall from tree foliage and why 99Tc appears to accumulate in forest floor leaf litter layers at the Oak Ridge study site.

Chromatography, Gel↗
PubMed1990

Analysis of binding of a technetium-99m-labeled monoclonal antibody to lentivirus-infected cells.

Caprine arthritis-encephalitis (CAE) is a model for the study of lentiviral infections. The authors' hypothesis is that radioimmunodetection has the potential to detect lentiviral proteins at the surface of infected cells. A monoclonal antibody (CAEV92A1) specific for a CAE virus (CAEV)-associated glycoprotein and a control antibody were radiolabeled with technetium-99m (99mTc) using the pretinning method. Cell binding assays were used to evaluate immunoreactivity and binding properties of 99mTc-labeled antibodies to CAEV-infected cells. 99mTc-CAEV92A1 bound preferentially to paraformaldehyde-fixed and live CAEV-infected cells. 99mTc-CAEV92A1 did not appear to be shed rapidly from its binding site.

Animals↗
PubMed1992

Comparative effects of neutral dipolar compounds and lipophilic anions on technetium 99m-hexakis (2-methoxyisobutyl isonitrile) accumulation in cultured chick ventricular myocytes.

RATIONALE AND OBJECTIVES: Non-flow-dependent myocellular accumulation and uptake kinetics of the myocardial perfusion and viability imaging agent, hexakis (2-methoxyisobutyl isonitrile) technetium 99m(I) (Tc-SESTAMIBI), are thermodynamically driven by large negative sarcolemmal and mitochondrial membrane potentials, and can be enhanced by addition of the lipophilic anion, tetraphenylborate (TPB). To further understand the general properties required of a co-administered compound for increasing the kinetic response of Tc-SESTAMIBI to membrane potential, a systematic appraisal of additional candidate lipid-soluble anions and neutral dipolar compounds was undertaken. METHODS: Each compound was biologically tested for its ability to enhance Tc-SESTAMIBI accumulation in a cultured heart cell model, and electronic dipole moments were evaluated using semi-empirical molecular orbital calculations. RESULTS: Of this series, phloretin (100 microM), TPB (10 microM), and to a lesser degree, 8-anilino-1-naphthalene sulfonate (100 microM) enhanced myocellular accumulation of Tc-SESTAMIBI. Phloretin enhancement was pH-dependent, showing maximal effect at pH 7.4, and was not additive to the augmentation induced by TPB. A series of additional lipid soluble anions and structural analogues of phloretin were without effect. CONCLUSION: Although selected compounds enhanced Tc-SESTAMIBI accumulation, overall, no direct relationship of dipole moment to biologic enhancement was demonstrated.

Anilino Naphthalenesulfonates↗
PubMed2001

Use of a new myocardial centroid for measurement of regional myocardial dysfunction by electron beam computed tomography: comparison with technetium-99m sestamibi infarct size quantification.

RATIONALE AND OBJECTIVES: The study compared the performance of conventional endocardial and epicardial centroid algorithms with the new "myocardial" centroid algorithm in patients with anterior myocardial infarction. "Floating" endocardial or epicardial centroid algorithms, commonly used in tomographic imaging methods to assess regional motion, may misrepresent left ventricular regional myocardial function in the presence of markedly asymmetric left ventricular contraction. METHODS: A new centroid algorithm based on regional myocardial mass distribution was tested in 29 patients with a first anterior myocardial infarction and was compared with conventional centroid algorithms. Direct comparisons in 60 equal sectors at one midventricular level per patient were performed between electron beam computed tomography and technetium-99m sestamibi single-photon emission computed tomography. The thresholds of regional myocardial function used to define infarction were varied for regional ejection fraction from 20% to 40% and for regional wall thickening from 0 to 4 mm. Regression and Bland-Altman analysis were used to compare infarct size by regional myocardial function with infarct size by sestamibi single-photon emission computed tomography. RESULTS: The new myocardial centroid showed the least shift toward infarcted myocardium from diastole to systole and had the highest amplitudes of the measurement curves for regional ejection fraction and regional wall thickening. The optimal regional myocardial function thresholds for each centroid algorithm for regional ejection fraction were endocardial, 30% (R = 0.62; mean difference to sestamibi, -0.5% +/- 22.1% tomographic infarct size points); epicardial, 30% (R = 0.79; mean difference, 2.2% +/- 13.1% tomographic infarct size points); and new myocardial, 25% (R = 0.88; mean difference, -0.6% +/- 9.5% tomographic infarct size points). The optimal thresholds for regional wall thickening were endocardial, 1 mm (R = 0.70; mean difference, -2.2% +/- 14.3% tomographic infarct size points); epicardial, 1 mm (R = 0.78; mean difference, -4.6% +/- 12.7% tomographic infarct size points); and new myocardial, 2 mm (R = 0.71; mean difference, 2.1% +/- 14.1% tomographic infarct size points). The best agreement (R = 0.88) between electron beam computed tomography infarct size and sestamibi single-photon emission computed tomography infarct size was achieved with regional ejection fraction and the new myocardial centroid algorithm. CONCLUSIONS: In asymmetrically contracting left ventricles, the new myocardial centroid algorithm is superior to conventional methods for tomographic analysis of regional myocardial function.

Algorithms↗
PubMed2002

Assessment of acetazolamide reactivity in cerebral blood flow using spectral analysis and technetium-99m hexamethylpropylene amine oxime.

Cerebral blood flow (CBF) can be quantified noninvasively using the brain perfusion index (BPI), determined from radionuclide angiographic data generated with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO). Previously, the BPI has been calculated using graphical analysis (GA); however, the GA method is greatly affected by the first-pass extraction fraction and retention fraction, which are not only variable, but lower in cases with an increased CBF, such as after the administration of acetazolamide. Thus, GA-calculated BPI values (BPIG) may not reflect the absolute CBF. The objective of this study was to use the spectral analysis of radionuclide angiographic data collected using 99mTc-HMPAO to examine changes in the BPI after the administration of acetazolamide. We studied the CBF of both cerebral hemispheres in six healthy male volunteers; the BPI was measured at rest and after the intravenous administration of 1 g of acetazolamide. In all participants, an H215O positron emission tomography (PET) examination was also performed, and the spectral analysis-calculated BPI values (BPIS) and BPIG values were compared with the actual CBF measured using H215O PET (mCBFPET). The BPIS was 1.070 +/- 0.051 (mean +/- SD) at rest and 1.497 +/- 0.098 after acetazolamide; the corresponding BPIG values were 0.646 +/- 0.073 and 0.721 +/- 0.107. The BPIS values were significantly correlated with the mCBFPET values, whereas the BPIG values were not. According to the BPIS values, the increase in BPI after the intravenous administration of acetazolamide was 40.1 +/- 8.4%, as opposed to an increase of only 11.3 +/- 6.5% according to the BPIG values. These results suggest that the spectral analysis of 99mTc-HMPAO-generated data yields a more reliable BPI than GA for the quantification of CBF after acetazolamide administration.

Acetazolamide↗
PubMed1997

The technetium white cell scan as an initial imaging investigation for evaluating suspected childhood inflammatory bowel disease.

BACKGROUND: The technetium white cell scan (WCS) may be a useful investigation for patients with inflammatory bowel disease (IBD). In a retrospective study we assessed the use of the WCS as an initial imaging investigation in evaluating children with suspected IBD. METHODS: Over a 3-year period, 60 WCS were performed on 55 patients (25 boys, median age 12.1 years, age range 1.5-18 years) with known or suspected IBD. There were two clinical groups: those with previously diagnosed IBD (histologically and radiologically) and in clinical relapse (13 patients), and newly presenting patients with suspected IBD (42 patients). RESULTS: Eighteen scans were performed on the 13 patients presenting with relapse. Seventeen were positive and one patient, subsequently shown to have an inactive stricture, had a negative scan. Seven of the 42 newly presenting patients had abnormal scans, confirmed to be due to IBD by a combination of histology and barium examinations. Of the remaining 35 scans, three were abnormal and 32 were normal. None of these patients were subsequently proven to have IBD. These results show that in detecting active IBD, a positive WCS has a 100% sensitivity (24/24) and a 91% specificity (32/35) in the diagnosis of IBD. CONCLUSIONS: Our results show that the WCS is very useful as an initial imaging investigation in evaluating patients with suspected IBD to select patients for further investigation.

Adolescent↗
PubMed1999

Clinical applications of technetium Tc 99m hexamethyl propylene amine oxime leukocyte scan in children with inflammatory bowel disease.

BACKGROUND: Labeled leukocyte imaging is a helpful diagnostic tool in the detection of inflammation and sepsis. The technetium Tc 99m hexamethyl propylene amine oxime (99mTc HMPAO)-labeled leukocyte scan has been found to be more sensitive than the Indium-111 labeled leukocyte scan in detecting inflammatory bowel disease, with reported sensitivities of 95% to 100%. Experience with the 99mTc HMPAO-labeled leukocyte scan was examined and its clinical applications evaluated in the immediate treatment of patients with inflammatory bowel disease. METHODS: A retrospective chart review was undertaken that included pediatric patients who underwent 99mTc HMPAO-labeled leukocyte scan at the James Whitcomb Riley Hospital for Children. The disease activity of patients with inflammatory bowel disease was assessed. The leukocyte scan was performed according to the manufacturer's specifications, and images were obtained 30 minutes and 2 hours after administration of the radiopharmaceutical. RESULTS: During the period of July 1996 through November 1997, 41 scans were performed in 35 patients. Twenty-nine patients had histologically proven inflammatory bowel disease: 24 with Crohn's disease, 4 with ulcerative colitis, and 1 with indeterminate colitis. Active inflammatory bowel disease was suspected in 24 patients when the leukocyte scan was performed. Twenty of the 24 patients (83% sensitivity) had abnormal findings in leukocyte scans that prompted more aggressive management in 15 (75%). Six of the 15 who were receiving maximum medical therapy underwent surgical resection of severely affected bowel segments, and medical treatment was intensified in the other 9. The remaining 5 patients were receiving optimal medical therapy, instituted at their recent visit, and did not require further medication adjustments. Four of the 24 patients with active inflammatory bowel disease had normal leukocyte scans (17% false-negative rate), 3 of whom were receiving corticosteroid therapy at the time the scans were performed. All of the 11 patients in whom inflammatory bowel disease was in remission and 6 patients who did not have inflammatory bowel disease had normal findings in leukocyte scans (100% specificity). CONCLUSIONS: Although a tissue diagnosis is still recommended, obtained during upper and lower gastrointestinal endoscopic examinations, and contrast radiography of the small bowel for the initial work-up of patients with suspected inflammatory bowel disease, the 99mTc HMPAO-labeled leukocyte scan is a safe and useful diagnostic adjunct for subsequent evaluation of patients known to have inflammatory bowel disease. The results of 99mTc HMPAO-labeled leukocyte scans directly influenced treatment of 75% of the study patients with active inflammatory bowel disease, which included the decision to refer patients for surgical intervention.

Adolescent↗
PubMed1979

The use of Technetium-99m stannous pyrophosphate scintigraphy to identify muscle damage in acute electric burns.

High-voltage electric burns are often associated with deep muscle damage in addition to a limited cutaneous burn. Technetium-99m stannous pyrophosphate (99mTc-PYP) scintigrams were evaluated as a diagnostic tool to detect and localize both large and focal areas of skeletal muscle necrosis. Scintigrams were performed in 14 patients between the first and fifth postinjury days and imaging was done over areas of suspected and clinically apparent muscle injury. Muscle damage was identified by an increased cellular uptake of the tagged material. All 14 patients had gross and histologic evidence of muscle necrosis. Muscle necrosis was identified as early as 24 hours and as late as 6 days postinjury. The location and extent of muscle injury was correctly ascertained preoperatively in all patients.

Burns, Electric↗
PubMed1992

A new method of diagnosing diaphragmatic injury using intraperitoneal technetium: case report.

The diagnosis of diaphragmatic laceration following blunt or penetrating trauma is often difficult to establish. Delay in recognition of this injury can be life threatening, resulting in herniation of abdominal viscera with possible strangulation or respiratory embarrassment. Previous animal studies from our institution have documented that intra-abdominal instillation of technetium sulfur colloid is a sensitive method to diagnose diaphragmatic disruption. We now present a case of diaphragmatic injury where the preoperative diagnosis was accurately made using this method when other imaging studies were inconclusive.

Adult↗
PubMed2001

Use of low-dose technetium Tc 99m sulfur colloid to locate sentinel lymph nodes in melanoma of the head and neck: preliminary study.

OBJECTIVES/HYPOTHESIS: Because sentinel lymph nodes are the first lymph nodes that drain a primary cancer site, results of sentinel lymph node (SLN) biopsy indicate status of the regional lymph nodes. Preoperative lymphoscintigraphy and intraoperative combined application of the handheld gamma probe and blue-dye technique (i.e., the "combined technique") was used previously to accurately identify the SLN, mostly in melanoma of the extremities and trunk and, sometimes, in melanoma of the head or neck, which is anatomically complex. Because of this complexity, melanoma in the head or neck is inherently problematic to treat: Localization of the SLN can be difficult or impossible because the primary cancer site can be near or overlapping the nodal basin. The objective of the present study was to determine the technical modifications and other considerations that can make SLN localization feasible in cases of melanoma occurring near or overlapping the nodal basin in the head or neck. STUDY DESIGN/METHODS: In a retrospective study of clinical records containing our database of melanoma diagnoses made between January 1996 and December 1999, we identified 27 patients diagnosed with stage I or II primary melanoma of the head or neck with clinically negative neck nodes who also had had preoperative lymphoscintigraphy. Of the 27 patients (17 male and 10 female patients; mean age, 54 y), 24 had SLN biopsy by intraoperative localization using both the handheld gamma probe and the blue-dye technique. RESULTS: Among the 27 patients who had SLN mapping, a median Breslow thickness of 1.8 mm was noted. Sentinel lymph node was noted at preoperative lymphoscintigraphy in 26 (96%) of the 27 patients. Activity of technetium Tc 99m (Tc-99m) sulfur colloid injected ranged from 10 to 1000 microCi (0.37 to 37 megabecquerel [MBq]). Intraoperative use of the combined technique for sentinel lymphadenectomy was successful in 92% of patients. Sentinel lymph nodes were identified in all 14 patients who received Tc-99m sulfur colloid at an activity level less than 60 microCi (2.2 MBq); mean activity level of injected TC-99m sulfur colloid was 28 microCi (1.04 MBq). Sentinel lymph nodes were identified in 8 (80%) of 10 patients who received Tc-99m sulfur colloid at an activity level greater than 100 microCi (3.7 MBq); mean activity of injected Tc-99m sulfur colloid in these patients was 482 microCi (17.8 MBq). A mean number of 1.4 sentinel lymph nodes per patient was identified at preoperative lymphoscintigraphy, and a mean number of 3 sentinel lymph nodes per patient was identified intraoperatively using the combined technique. Tumor recurrence was seen in 2 (10%) of the 19 patients who had cancer-free SLN at mean follow-up of 18 months (range, 1 to 47 mo). Sentinel lymphadenectomy of the parotid region did not injure the facial nerve in any patients. CONCLUSIONS: For patients with primary melanoma that is near or overlaps the nodal basin in the head or neck, SLN biopsy can be accurately performed using Tc-99m sulfur colloid at low activity levels (10 microCi to 60 microCi [0.37 to 2.2 MBq]. However, background radiation from the primary injection site can incorporate the SLN, making localization at preoperative lymphoscintigraphy difficult if not impossible; therefore, the high doses commonly used for melanoma of the extremities and trunk (500 to 2000 microCi [18.5 to 74 MBq]) should not be used for melanoma of the head or neck if the primary site is near or overlaps the nodal basin. In addition, absorption of Tc-99m sulfur colloid by salivary glands increases background radiation in the nodal basin; therefore, use of the handheld gamma probe for intraoperative localization of SLN can be problematic in regions where lymph nodes are adjacent to or within the substance of the salivary gland (i.e., the submandibular and parotid glands).

Female↗
PubMed1986

Technetium-99m-glucoheptonate lung imaging; has it a role in the diagnosis of bronchial carcinoma?

It has been shown by Vorne et al. and Passamonte et al. that technetium-99m-glucoheptonate (Tc-GH) concentrates in bronchial carcinomas. The two studies reported similar sensitivities (88 and 91%, respectively) but discordant specificities (88 and 10%, respectively). In order to assess the uptake of Tc-GH in bronchial carcinomas we performed lung imaging on patients with an abnormal chest radiograph who were undergoing routine investigations for bronchial carcinoma. 108 patients (85 carcinoma, 23 non-carcinoma) were given 555 MBq (15 mCi) Tc-GH intravenously and scanned 5 h later. Images were assessed by one investigator (J.A.L.) without knowledge of the patient's clinical details or other results. Localized uptake of Tc-GH was seen in 71 out of 85 patients who proved to have bronchial carcinoma. Uptake was also seen in 16 out of 23 patients with a variety of non-malignant lung conditions. Sensitivity for bronchial carcinoma was 84%, and specificity 30%. Uptake did not vary significantly with histology. Eleven out of 12 patients with proven tuberculosis had increased uptake of Tc-GH; two of those patients also had inactive lesions which did not concentrate the tracer. In conclusion, Tc-GH is of limited value in the diagnosis of bronchial carcinoma, because of its low specificity. A possible role in the diagnosis of active tuberculosis may exist, following further assessment.

Adult↗
PubMed1987

The preparation of kits for labelling macromolecules of biological interest with technetium-99m.

A method has been developed for producing 'kits' for labelling porphyrins, dextrans, myoglobin and cytochromes with technetium-99m. The kits have a shelf life of at least 3 months and can be reconstituted by the simple addition of 99TcmO4 from a commercial generator diluted in a buffer. The most suitable buffer was found to be isotonic citrate/saline at pH 9.0 to 9.5. When the kits are prepared as described and reconstituted with the above buffer, labelling yields of more than 95% are routinely achieved and polymerization or stacking of the labelled compounds is prevented.

Cytochrome c Group↗
PubMed2004

Optimization of technetium-99m Sestamibi single-photon emission tomography to define multidrug resistance with confidence.

BACKGROUND: The efflux rate of technetium-99m Sestamibi (99mTc-Sestamibi) is a kinetic phenomenon related to the response of cancer cells to chemotherapy, and may be used to determine drug resistance. Measurement of the efflux rate requires accurate quantitative single-photon emission tomography (SPET) imaging within the time constraints imposed by the kinetics of the process. METHODS: A phantom study, at activity concentrations typically found with 99mTc-Sestamibi in vivo, was undertaken to optimize the SPET parameters and, in particular, to determine whether 180 degrees acquisition arcs with heads in 'L' configuration could be used for accurate quantification. Following the development of the most appropriate SPET protocol, a small patient pilot study was undertaken. RESULTS: Studies designed to evaluate statistical uncertainty (noise), contrast restitution and spatial resolution of the data sets, using different acquisition and reconstruction parameters, showed that 180 degrees SPET using a 64 x 64 matrix, 6 degrees angular sampling and iterative reconstruction was optimal. Finer linear and/or angular sampling afforded negligible improvement in resolution, but markedly increased the statistical uncertainty. Comparison of 360 degrees and 180 degrees acquisitions, utilizing conventional filtered backprojection and iterative reconstruction algorithms, demonstrated that the statistical uncertainty was reduced to a greater extent for 180 degrees data collection. For 360 degrees (64 x 64) data acquisition, statistical uncertainty decreased from 15% to 11% using the iterative algorithm, whilst the 180 degrees (64 x 64) data showed a reduction from 20% to 7%, and approached values obtained by planar imaging. The efflux measurements obtained in the patient pilot study were consistent with the observed chemotherapy response. CONCLUSION: Our study shows that 180 degrees acquisition arcs are a practical option for accurate quantitative SPET kinetic imaging for potential studies of chemotherapy response in patients with lung cancer.

Algorithms↗
PubMed1987

Technetium bone scintigraphy in the diagnosis of osteomyelitis in children.

In a 5 1/2-year retrospective study of hospitalized children with osteomyelitis who had technetium bone scans, we found that 32 of 38 (84%) had increased radionuclide uptake, 4 (11%) had normal uptake and 2 (5%) had decreased uptake. The two patients with decreased uptake had a stormy course with extensive bone destruction and pathologic fractures in spite of prolonged courses of antibiotic therapy. Decreased uptake on bone scan in patients with clinical evidence of osteomyelitis could indicate a poor prognosis and early surgical drainage is indicated in order to decrease morbidity.

Adolescent↗
PubMed1994

Use of technetium Tc 99m sestamibi and iodine 123 radionuclide scan for preoperative localization of abnormal parathyroid glands in primary hyperparathyroidism.

The imaging methods currently used to localize the parathyroid gland in patients with hyperparathyroidism have been criticized as unreliable and even misleading. We evaluated a new imaging technique that uses technetium Tc 99m sestamibi and iodine 123. We studied 21 patients having a diagnosis of primary hyperparathyroidism and no previous parathyroid surgery. Scintigraphy to localize the abnormal parathyroid was done before operation. A solitary adenoma was localized in 14 patients. Six patients had images consistent with diffuse hyperplasia, and one patient had a dual adenoma. The surgical and histologic findings confirmed the preoperative data. The sensitivity of this method is 87.5%, the specificity is 100%, and the predictive value is 100%. This new method of preoperative localization of abnormal parathyroid glands is useful in patients having initial neck exploration for primary hyperparathyroidism.

Adenoma↗
PubMed1992

Technetium-99m sulfur colloid accumulation as a predictor of acute renal transplant rejection.

Renal transplantation is the preferred treatment for end-stage renal disease in children. Most transplant failures are due to allograft rejection. To date, only histopathological findings on renal biopsy can establish this diagnosis. Prior to the availability of cyclosporine, technetium-99m sulfur colloid nuclear scans (TSC) were used in a limited number of institutions to detect rejection episodes. The purpose of this study was to determine whether TSC could predict acute rejection in the cyclosporine era. A prospective study involving 41 pediatric renal transplant patients (M = 25, F = 16) was conducted from 6/1/89 to 10/31/91. Patients who received a TSC and biopsy (41 patients, 62 studies) within one week of clinical and laboratory evidence of acute rejection were included in the study. A qualitative method of determining sulfur colloid uptake was used by comparing allograft uptake with that of the fifth lumbar vertebrae (L5) marrow uptake: 3(+)--allograft with greater than L5 marrow uptake, 2(+)--same as, 1(+)--less than, and 0--no allograft uptake. Transplant accumulation of > or = 2+ was considered consistent with acute rejection (P < 0.001). Acute rejection was noted in 53 of 62 renal biopsies. Of those with biopsy-proved acute rejection, SC was positive (> or = 2+) in 46 of 53. SC of > or = 2+ has proved to be a good predictor of acute rejection. This technique has a sensitivity of 98%, specificity of 53%, positive predictive value of 87%, and negative predictive value of 89%.

Adolescent↗
PubMed2002

Delayed graft function is characterized by reduced functional mass measured by (99m)Technetium-mercaptoacetyltriglycine renography.

BACKGROUND: The mechanism that underlies delayed graft function (DGF) is still poorly defined. Previous studies using tubular function tests have shown that postischemic injury to the renal transplants results in profound impairment of paraimmunohippurate (PAH) extraction through the tubules. METHODS: Using (99m)Technetium-mercaptoacetyltriglycine ((99m)Tc-MAG3) renography and tubular function slope (TFS), a study of the tubular uptake of (99m)Tc-MAG3 was undertaken in a prospective study of renal transplant recipients with immediate graft function (IGF) and those with DGF. RESULTS: A total of 37 consecutive recipients of a cadaveric graft and 5 kidneys from living donors was evaluated within 48 hours after transplantation and in week 2, months 3 and 6, and 3 years after transplantation. In addition to the protocol scans, recipients with DGF were examined every other day until function was resumed. Repeated measurement two-way analysis of variance and a change point analysis were performed to determine the difference in the follow-up of TFS values between the two groups. Fourteen patients were classified as having DGF and 28 immediate graft function. In the DGF group, the initial TFS value was significantly lower than in the immediate graft function group (0.54 [+/-0.01] and 1.75 [+/-0.16], respectively; P=0.002), a difference that persisted for up to 3 years. Change point analysis revealed that the postischemic tubular excretion improved with time in both groups in the first 3 to 4 weeks, but both groups remained different up to 3 years after transplantation. Multivariate analysis revealed that only the cold ischemic time was an independent risk factor for a low TFS value. After the initial recovery from postischemic injury, the TFS may be used as a marker for functional renal mass. CONCLUSION: We propose that the tubular defect in DGF, as defined by (99m)Tc-MAG3 renography, is irreversible and may be a marker of initial graft function.

Adult↗