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PubMed1998

Changes in the thyroid technetium-99m scintigram after antithyroid and subsequent radioiodine treatment for solitary autonomous nodules.

In patients with solitary autonomous thyroid nodules, the treatment of choice is radioiodine (131I) therapy, eventually preceded by antithyroid drugs to avoid aggravation of hyperthyroidism. The aim of this study was to evaluate the scintigraphical results of 131I treatment when using antithyroid pretreatment. Twenty-four patients having a solitary autonomous thyroid nodule were studied. A technetium-99m (99mTc) pertechnetate scintigraphy was performed at the time of diagnosis, when serum thyrotropin (TSH) had been normal for about 3 months on antithyroid drug treatment, and finally when serum TSH was normalized after 131I treatment. The primary scintigram showed suppression of 99mTc pertechnetate in the paranodular thyroid tissue in all patients. The second scintigram showed normal uptake in the paranodular tissue in 22 patients and a continuing suppression of the paranodular tissue in 2 patients. The third scintigram showed a solitary adenoma in 14 patients with none or almost no uptake in the paranodular tissue, resembling the first scintigram. In 6 patients an adenoma was still present, but uptake was seen in the paranodular tissue; in 3 patients a homogenous uptake without any sign of the previous nodule, and in 1 patient very low uptake in the gland was seen. Four patients developed hypothyroidism in the follow-up period of approximately 1 year. Pretreatment with antithyroid drugs induced an increase in serum TSH, stimulating the paranodular tissue. 131I will therefore be distributed in the whole thyroid gland, and not only in the autonomous solitary nodule. After 131I treatment, we continuously found a solitary nodule with low uptake in the paranodular tissue in 20 of 24 patients.

Adenoma↗
PubMed1977

Infarct sizing with technetium-99m stannous pyrophosphate scintigraphy in dogs and man; relationship between scintigraphic and praecordial mapping estimates of infarct size in patients.

The present study was performed in order to evaluate the ability of technetium-99m stannous pyrophosphate (99mTc-PYP) myocardial scintigrams to size infarcts in experimental animals and man. In 10 dogs with proximal left anterior descending coronary artery occlusion and acute anterior myocardial infarcts, there was a significant correlation between scintigraphic infarct size and histological infarct weight (P less than 0.01). In 25 patients with acute anterior or anterolateral myocardial infarcts, there was a significant correlation between relatively large infarct size determined scintigraphically and the acute development of left ventricular failure. There was some overlap, however, in 99mTc-PYP scintigraphic infarct size between patients who did and did not develop left ventricular failure with infarction. Presumably this is explained by some patients having had earlier myocardial damage and thus developing left ventricular failure with relatively small new infarcts. There was also a statistically significant, but weak, correlation in patients between scintigraphic infarct size and precordial ST segment mapping including peak ST segment elevation (P less than 0.05) and the number of praecordial sites with ST segment elevation equal to or greater than 2 mm (P less than 0.01). The data suggest that 99mTc-PYP scintigrams and praecordial mapping measure some similar but some dissimilar aspects of infarct size in patients, and that 99mTc-PYP scintigraphy does size acute anterior and anterolateral infarcts in experimental animals and patients.

Animals↗
PubMed1979

Regional 99m technetium diphosphonate uptake in experimental dog heart infarct: relation to duration and severity of ischaemia.

Regional uptake of 99mTechnetium diphosphonate was compared with regional myocardial blood flow 6, 12 and 24 h after the onset of myocardial infarction in dogs, and with regional creatine kinase depletion 24 h after the onset. Uptake of the imaging agent increased from 6 to 24 h, but no consistent relationship could be demonstrated between regional myocardial blood flow and regional uptake of the diphosphonate nor between uptake and regional creatine kinase depletion at the centre or border of the infarct. In addition, inappropriately high levels of 99m Technetium uptake could be demonstrated in the epicardial layer of the normal tissue surrounding the infarct. We conclude that diphosphonate uptake is not quantitatively related to the severity of ischaemia, and that use of this substance for imaging may over-estimate myocardial infarct size.

Animals↗
PubMed1986

Use of technetium-99m methylene diphosphonate and gallium-67 citrate scans after intraarticular injection of Staphylococcus aureus into knee joints of rabbits with chronic antigen-induced arthritis.

Numerous clinical studies have questioned the ability of radionuclide scans to differentiate septic from aseptic joint inflammation. A clinical study may not be able to document an underlying disease process or duration of infection and, thus, may make conclusions about the accuracy of scan interpretations open to debate. In this study, the Dumonde-Glynn model of antigen-induced arthritis in rabbits was used as the experimental model to study technetium and gallium scans in Staphylococcus aureus infection of arthritic and normal joints. Gallium scans were negative in normal rabbits, usually negative in antigen-induced arthritis, but positive in septic arthritis. The bone scan was usually negative in early infection but positive in late septic arthritis, a finding reflecting greater penetration of bacteria into subchondral bone because of the underlying inflammatory process.

Animals↗
PubMed2002

Prediction of chemotherapy response in untreated malignant lymphomas using technetium-99m methoxyisobutylisonitrile scan: comparison with P-glycoprotein expression and other prognostic factors. A preliminary peport.

BACKGROUND: The purpose of this study was to predict chemotherapy response in untreated malignant lymphomas using technetium-99m methoxyisobutylisonitrile (Tc-MIBI) scan. METHODS: Twenty-five patients with malignant lymphoma were studied before receiving chemotherapy. Early Tc-MIBI scan was performed 10 min after intravenous injection of Tc-MIBI. Immunohistochemical analyses were performed on multiple non-consecutive sections of the biopsy specimens to determine Pgp expression. Chemotherapy response was evaluated in the first 1-2 years after completion of treatment by clinical and radiological methods. RESULTS: The mean tumor-to-background ratio of the 15 patients with good response (3.3 +/- 0.6) was significantly higher than that of the 10 patients with poor response (1.2 +/- 0.1). Among the 15 patients with good response to chemotherapy, all had positive Tc-MIBI scan results but negative Pgp expression. Among the 10 patients who had poor response to chemotherapy, all 10 had negative Tc-MIBI scan, but six patients had positive Pgp expression and four had negative Pgp expression. Significant differences were found in the incidences of good and poor responses determined by Tc-MIBI scan and Pgp expression. However, there were no significant differences in the incidences of good and poor responses for other prognostic factors. CONCLUSION: Compared with other prognostic factors, early Tc-MIBI scan more accurately predicts chemotherapy response in patients with malignant lymphoma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

Concordance between abdominal scintigraphy using technetium-99m hexamethylpropylene amine oxime-labelled leucocytes and ileocolonoscopy in patients with spondyloarthropathies and without clinical evidence of inflammatory bowel disease.

OBJECTIVE: To study the concordance between abdominal scintigraphy using technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO)-labelled leucocytes (ASTLL) and ileocolonoscopy in patients with spondyloarthropathies (SpA) and without clinical evidence of inflammatory bowel disease (IBD). PATIENTS AND METHODS: Fifteen patients with SpA (European Spondylarthropathy Study Group 1991 criteria) without clinical evidence of IBD were studied prospectively with ASTLL and ileocolonoscopy. RESULTS: This cohort consisted of seven men and eight women aged 31.8+/-10.5 yr (18-47) [mean age +/- S.D. (range)] and with a disease duration of 6.0+/-4.4 yr (0.4-15). ASTLL showed abnormal uptake in four patients. Ileocolonoscopy was abnormal in five patients, showing acute inflammatory lesions in one patient with reactive arthritis, undifferentiated chronic inflammatory lesions in two cases, and features indistinguishable from those of Crohn's disease in two cases. ASTLL was negative in two cases in which ileocolonoscopy showed inflammatory lesions and was positive (terminal ileum) in one case with normal ileocolonoscopy. The concordance between the two examinations was statistically significant (kappa = 0.53; P = 0.008). CONCLUSION: ASTLL may be an interesting tool to detect subclinical gut inflammation in patients with SpA.

Abdomen↗
PubMed2001

The role of technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography (SPECT) in the detection of cardiovascular involvement in systemic lupus erythematosus patients with non-specific chest complaints.

OBJECTIVES: Systemic lupus erythematosus (SLE) can affect multiple organs. Coronary artery disease has received increasing recognition as a major cause of morbidity and mortality in SLE in recent years. The purpose of this study was to evaluate the utility of technetium-99m sestamibi single-photon emission computed tomography ((99m)Tc-sestamibi SPECT) in the detection of cardiovascular involvement in SLE patients with non-specific clinical chest symptoms such as chest discomfort and/or dyspnoea and/or occasional palpitation. METHODS: Thirty-three SLE female patients (age range: 22-45 yr) with non-specific complaints such as chest discomfort and/or dyspnoea and/or occasional palpitation were investigated using a (99m)Tc-sestamibi myocardial perfusion SPECT scan at rest and after dipyridamole infusion in a stress study. The age- and sex-matched healthy group (24 cases) and SLE patients without any cardiovascular symptoms/signs (28 cases) were also included as controls in this study. The results of the uptake pattern of (99m)Tc-sestamibi were classified into four types including normal, persistent perfusion defect, reversible perfusion defect and reverse redistribution. RESULTS: Perfusion abnormalities were detected in 27 cases (seven patients had persistent perfusion defects, 15 patients had reversible perfusion defects, one patient had both persistent and reversible perfusion defects, two patients showed a reverse redistribution pattern and two patients had both reversible perfusion defects and a reverse redistribution pattern). The results of the SPECT in the healthy group were all normal. However, perfusion abnormalities were detected in 12 cases in the group of asymptomatic SLE patients. CONCLUSIONS: (99m)Tc-sestamibi myocardial perfusion SPECT is a useful non-invasive imaging modality to detect cardiovascular involvement in SLE patients with non-specific clinical complaints of heart disease.

Adult↗
PubMed1999

Extrahepatic regional chemotherapy: use of technetium-99m labeled macroaggregated albumin.

The purpose of this study was to verify the applicability of nuclear techniques with technetium-99m labeled macroaggregated albumin (Tc-99m-MAA) in extrahepatic regional chemotherapy. Of 98 patients in whom arterial Port-a-caths were implanted by transcutaneous access, 13 were treated by regional extrahepatic chemotherapy (breast, one; pancreas, four; kidney, one; uterus, three; vagina, two; bladder, two). In all 13 patients, Tc-99m-MAA was slowly infused intraarterially. The examination showed the perfusion of the area with the neoplasm and excluded the presence of important misperfusions of Tc-99m-MAA to the nearest areas. To detect the presence of an arteriovenous shunt with systemic misperfusion, an anterior image of the thorax was obtained in all patients and an index of misperfusion was calculated. In 12 patients, the index was < 5%; in one patient it was about 40%. In conclusion, our preliminary experience concerns the monitoring of intraarterial infusion chemotherapy of extrahepatic districts. In all 13 patients, we evaluated the correct positioning of the intraarterial catheter and the distribution pattern of the arterial flow, with a semiquantitative indication of arteriovenous shunting. This method gave us an instrument of study that was inexpensive, harmless, and free of collateral complications.

Aged↗
PubMed1998

Technetium-99m-labeled white blood cells: a new method to define the local and systemic role of leukocytes in acute experimental pancreatitis.

OBJECTIVE: We developed a new method to quantitate leukocyte accumulation in tissues and used it to examine the time course and severity of acute experimental pancreatitis. BACKGROUND: Leukocyte activation and infiltration are believed to be critical steps in the progression from mild to severe pancreatitis and responsible for many of its systemic complications. METHODS: Pancreatitis of graded severity was induced in Sprague-Dawley rats with a combination of caerulein and controlled intraductal infusion. Technetium-99m (99mTc)-labeled leukocytes were quantified in pancreas, lung, liver, spleen, and kidney and compared with myeloperoxidase activity. The severity of pancreatitis was ascertained by wet/dry weight ratio, plasma amylase, and trypsinogen activation peptide in the pancreas. The time course of leukocyte accumulation was determined over 24 hours. RESULTS: Pancreatic leukocyte infiltration correlated well with tissue myeloperoxidase concentrations. In mild pancreatitis, leukocytes accumulated only in the pancreas. Moderate and severe pancreatitis were characterized by much greater leukocyte infiltration in the pancreas than in mild disease (p < 0.01), and increased 99mTc radioactivity was detectable in the lung as early as 3 hours. 99mTc radioactivity correlated directly with the three levels of pancreatitis. CONCLUSIONS: Mild pancreatitis is characterized by low-level leukocyte activation and accumulation in the pancreas without recruitment of other organs; marked leukocyte accumulation was found in the pancreas and in the lung in more severe grades of pancreatitis. These findings provide a basis for the pathophysiologic production of cytokines and oxygen free radicals, which potentiate organ injury in severe pancreatitis. This study validates a new tool to study local and systemic effects of leukocytes in pancreatitis as well as new therapeutic hypotheses.

Acute Disease↗
PubMed2001

Multicenter trial of sentinel node biopsy for breast cancer using both technetium sulfur colloid and isosulfan blue dye.

OBJECTIVE: To determine the factors associated with false-negative results on sentinel node biopsy and sentinel node localization (identification rate) in patients with breast cancer enrolled in a multicenter trial using a combination technique of isosulfan blue with technetium sulfur colloid (Tc99). SUMMARY BACKGROUND DATA: Sentinel node biopsy is a diagnostic test used to detect breast cancer metastases. To test the reliability of this method, a complete lymph node dissection must be performed to determine the false-negative rate. Single-institution series have reported excellent results, although one multicenter trial reported a false-negative rate as high as 29% using radioisotope alone. A multicenter trial was initiated to test combined use of Tc99 and isosulfan blue. METHODS: Investigators (both private-practice and academic surgeons) were recruited after attending a course on the technique of sentinel node biopsy. No investigator participated in a learning trial before entering patients. Tc99 and isosulfan blue were injected into the peritumoral region. RESULTS: Five hundred twenty-nine patients underwent 535 sentinel node biopsy procedures for an overall identification rate in finding a sentinel node of 87% and a false-negative rate of 13%. The identification rate increased and the false-negative rate decreased to 90% and 4.3%, respectively, after investigators had performed more than 30 cases. Univariate analysis of tumor showed the poorest success rate with older patients and inexperienced surgeons. Multivariate analysis identified both age and experience as independent predictors of failure. However, with older patients, inexperienced surgeons, and patients with five or more metastatic axillary nodes, the false-negative rate was consistently greater. CONCLUSIONS: This multicenter trial, from both private practice and academic institutions, is an excellent indicator of the general utility of sentinel node biopsy. It establishes the factors that play an important role (patient age, surgical experience, tumor location) and those that are irrelevant (prior surgery, tumor size, Tc99 timing). This widens the applicability of the technique and identifies factors that require further investigation.

Adult↗
PubMed1997

The diagnostic value of magnetic resonance imaging and technetium 99m-HMPAO single-photon-emission computed tomography for the diagnosis of Alzheimer disease in a community-dwelling elderly population.

The objective of this study was to assess the diagnostic value for Alzheimer disease (AD) of single-photon-emission computed tomography (SPECT) and magnetic resonance imaging (MRI), separately and in combination. The study was part of a two-stage population-based study of mental functioning among noninstitutionalized 65-to 85-year-olds living in Amsterdam, The Netherlands. Participants (n = 51) were randomly selected within strata of cognitive function to obtain a sample of AD patients (n = 10) and clinically normal subjects (n = 41), of whom 22 displayed some cognitive impairment and fulfilled criteria for "minimal dementia" according to the Cambridge Examination for Mental Disorders of the Elderly. Coronal T1-weighted MRI was used to visualize the medial temporal lobe. Medial temporal lobe atrophy (MTA) was assessed qualitatively on a 0-4 scale. Regional cerebral blood flow on SPECT was assessed with the use of technetium 99m-HMPAO in three manually drawn regions of interest (frontal, parietal, and temporoparietal). Ratios were calculated by using the cerebellum as the reference area. MTA differed significantly between AD patients and clinically normal subjects (p = 0.0009), with sensitivity for AD of 70% and a specificity of 76%. None of the three SPECT ratios differed between normal and AD subjects. The temporoparietal/cerebellar ratio had a sensitivity of 30% and a specificity of 71% as a cutoff of 0.76. When both tests were positive the combined sensitivity was low (20%), but the false-positive rate was also very low (5%). A negative result on MRI or any SPECT ratio yielded a high specificity (93%-98%) but also a high false-negative rate (60-80%). Adding SPECT to MRI seems useful only if a diagnosis of AD is suspected clinically and confirmation is needed. When the clinical probability that AD is absent is high, normal results on either MRI or SPECT may confirm this notion. Given the fact that structural imaging should be performed in a clinical workup for dementia, using MRI only would be the most cost-effective approach.

Aged↗
PubMed1978

Right subhepatic abscesses detected by technetium liver scans.

A focal defect at the inferior margin of the right lobe of the liver was found in two patients with subhepatic abscesses. This defect must be differentiated from the porta hepatis and the gallbladder fossa. When technetium liver scans are obtained in patients with usspect abdominal abscesses, the inferior margin of the right lobe of the liver should be carefully scrutinized so that right subhepatic abscesses will not be overlooked.

Abdomen↗
PubMed1990

Persistent splenic visualization on technetium-99m DISIDA hepatobiliary studies.

Tc-99m DISIDA is widely used for studying a variety of biliary conditions. It is generally recognized that the spleen is normally visualized on DISIDA imaging only during the blood pool phase. Upon review of our experience with DISIDA, visualization of the spleen was found more common than generally acknowledged. All DISIDA examinations performed at our two institutions were retrospectively reviewed; 95 studies were performed at Institution #1 and 150 studies at Institution #2. There were 138 men and 107 women. Quality control to confirm radiochemical purity included sephadex gel column chromatography. Of 245 patient studies, persistent splenic visualization was identified in one patient (1.0%) at Institution #1 and in 11 patients (7.3%) at Institution #2. There was no correlation between age, sex or final diagnosis and persistent visualization of the spleen. It is suggested that persistent splenic visualization may be caused by an elevated concentration of reduced hydrolized technetium (colloid) in DISIDA.

Biliary Tract Diseases↗
PubMed1990

Sequential technetium-99m sulfur colloid/indium-111 white blood cell imaging in macroglobulinemia of Waldenstrom.

Technetium-99m sulfur colloid (SC) and indium-111 labeled leukocyte (In-111 WBC) scintigraphy was performed on a 77-year-old female patient to rule out a left periprosthetic infection. Anterior Tc-99m SC and In-111 WBC images of the pelvis and femurs revealed no abnormal deposition of radiotracer about the Austin-Moore prosthesis. Absent radiotracer uptake, however, was demonstrated within the left hemipelvis. A left iliac bone marrow aspirate and biopsy revealed a lymphoplasmacytic infiltrate consistent with Waldenstrom's macroglobulinemia.

Aged↗
PubMed2001

Pelioid-type hepatocellular carcinoma masquerading as a hepatic hemangioma on technetium-99m red blood cell scintigraphy.

Technetium-99m red blood cell (RBC) scintigraphy is a very specific method to differentiate a hemangioma from other hepatic masses. The authors report a case of hepatocellular carcinoma that showed a focal area of increased uptake on Tc-99m RBC SPECT in a 60-year-old man. Dynamic computed tomography and angiography revealed features of both hemangioma and hepatocellular carcinoma. Pathologic examination showed that the portion of the hepatocellular carcinoma that showed increased uptake on Tc-99m RBC scintigraphy had peliosis, which is the likely cause of the radiotracer avidity.

Carcinoma, Hepatocellular↗