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PubMed1982

[Diagnostic significance of the colloid concentration in the static liver scintigram].

The count density in the right liver lobe is presented as a parameter for the recognition of diffuse parenchymal diseases of the liver by means of static colloidal scanning. Sensitivity, specificity, and accuracy (87-100%) in separating normal from parenchymal damage and cirrhosis are comparable to the results of dynamic sequence scanning. Since this parameter is easy to be measured it is proposed for clinical application.

Chronic Disease↗
PubMed1986

[Demonstration and localization of hemorrhage in the intestinal tract. Comparison between 99mTc-colloid scintigraphy and selective angiography of the visceral vessels].

In 17 patients with suspected bleeding in the lower intestinal tract 23 scintigraphic studies were performed with Tc-colloid, followed in each case by visceral-artery angiography. Comparison of the two methods with the final clinical diagnosis indicated that angiography was correct in 6 of 23 examinations (26%), scintigraphy in 12 of 23 (52%). All scintigraphically negative results were negative also angiographically. Noninvasive, relatively unstressful scintigraphy should be performed for immediate diagnosis in any case of acute bleeding. Emergency-type angiography is reasonably performed only if scintigraphy is positive.

Adult↗
PubMed1982

[The place of lymphoscintigraphy in the treatment of malignant melanoma of the skin (author's transl)].

Lymphoscintigraphy was performed pre- or postoperatively in 42 patients with malignant melanoma of the skin. The test consisted of the injection of 1.5-2.0 mCi 99mTc-labelled antimony sulphide colloid, both intracutaneously and subcutaneously, either around the primary tumour or along its edges or into the centre of the excision scar or contralaterally. The draining lymph-node groups were scanned with a gamma-camera 4-6 hours after the injection. Except for one patient, the radioactive tracer had always disappeared from the injection site and had accumulated in th regional lymph-nodes. In 11 of 28 patients with melanoma on the trunk, lymphatic drainage was to more than one regional lymph-node group. In most cases with cutaneous melanoma on the trunk, lymphatic drainage could not be anatomically predicted, but easily and unequivocally identified by lymphoscintigraphy. On the other hand, lymphatic drainage of a melanoma of the head or neck, as well as of distal segments of the limbs, almost always followed anatomical expectations. Using lymphoscintigraphic findings, prophylactic lymphadenectomy could be performed selectively in "high risk" melanomas.

Adult↗
PubMed2002

Comparison between periareolar and peritumoral injection of radiotracer for sentinel lymph node biopsy in patients with breast cancer.

BACKGROUND: The technique of sentinel lymph node (SLN) biopsy in patients with breast cancer varies among reports, and the optimal method remains to be established, particularly with regard to the site of radiotracer injection. The aim of this study was to compare periareolar and peritumoral injection of radiotracer in detecting SLN in patients with breast cancer. METHODS: Patients with T1-2 breast cancer (n = 155) were enrolled in this study. In phase 1 (n = 62), SLN biopsy was performed by using peritumoral injection of blue dye alone followed by backup axillary lymph node dissection. In phase 2, SLN biopsy was performed by using peritumoral injection of blue dye and peritumoral (group A, n = 41) or periareolar (group B, n = 52) injection of technetium 99m tin colloid. RESULTS: In phase 1, the detection rate of SLN was 81% and the false-negative rate was 5.6%, indicating our skill in SLN biopsy. In phase 2, the success rate of lymphoscintigraphy was significantly (P <.001) higher in group B (90%) than in group A (51%). The mean ex vivo radioactivity of SLN in group B (117 counts per second; range, 5 to 900) was also significantly (P <.05) higher than in group A (51 counts per second; range, 8 to 260). In addition, the detection rate of SLN was significantly (P <.05) higher in group B (100%) than in group A (90%). CONCLUSIONS: Periareolar injection of radiotracer for SLN biopsy is superior to peritumoral injection because of its simplicity, achieving a high success rate in lymphoscintigraphy and SLN detection.

Adult↗
PubMed2003

The function of the spleen in adults after ligation of the splenic artery of the traumatized spleen in childhood.

BACKGROUND: Ligation of the splenic artery (LSA) has been successfully used as a spleen-saving procedure in rare cases of splenic trauma in children in which management with splenorrhaphy or partial splenectomy alone was not possible. There are no data regarding the long-term effects of the procedure on the functional status of the spleen. The purpose of this study is to present and discuss our clinical and laboratory findings in adults who underwent LSA in childhood. METHODS: Our first 2 patients in whom LSA was done at ages 4 and 2 years in 1977 underwent the following examinations in the year 2000: 1, imaging of the spleen; 2, immunologic studies; and 3, peripheral blood tests. Their ages at reexamination were 27 and 25 years, respectively. RESULTS: Results were as follows: triplex ultrasound revealed normal size and echomorphology; Doppler techniques revealed normal vasculature; 99mTc-Tin colloid scanning revealed normal uptake. Immunoglobulins (IgG1 to IgG4, IgA, IgM, IgE), complement fraction (C3, C4), antibodies response to vaccinations, and peripheral blood tests all had normal results. No Howell-Jolly bodies were found. CONCLUSION: Laboratory investigations in adults with LSA during childhood disclosed undisturbed function of the spleen. LSA can be used as an adjunct to splenorrhaphy in children with rare splenic injuries involving major hilar vessels.

Adult↗
PubMed2002

Use of technetium-99m tin colloid for sentinel lymph node identification in non-small cell lung cancer.

BACKGROUND: To test the reliability of sentinel lymph node identification in non-small cell lung cancer, sentinel nodes were localized with a radioactive colloid in patients undergoing surgery. METHODS: Forty-six patients with non-small cell lung cancer undergoing curative resection with mediastinal lymph node dissection were examined. The day before surgery, technetium-99m ((99m)Tc) tin colloid was injected into the peritumoral region. At operation, the radioactivity of the lymph nodes was counted with a handheld gamma counter before (in vivo) and after (ex vivo) dissection. Lymph nodes with an ex vivo radioactive count more than 10 times the background value were identified as sentinel nodes. The correlation between the in vivo and ex vivo results was examined. RESULTS: Lymphoscintigraphy revealed that it took longer than 6 hours for sufficient (99m)Tc tin colloid to reach the sentinel nodes. Sentinel nodes could be identified in 40 patients (87%). Patients whose sentinel nodes could not be identified had a significantly lower ratio of forced expiratory volume in 1 second to forced vital capacity than did those with identifiable sentinel nodes (P =.03). No false-negative sentinel nodes were detected in 14 patients with N1 or N2 disease (0%). In the hilar lymph node stations, the lobar lymph nodes were most frequently identified as sentinel nodes (as often as 85% of the time). Fourteen patients (35%) had sentinel nodes in the mediastinum, the distribution of which depended on the lobe. In vivo and ex vivo counting showed 88% concurrence for the identification of sentinel nodes in mediastinal lymph node stations. CONCLUSION: The identification of sentinel nodes with (99m)Tc tin colloid is a reliable method of establishing the first site of nodal metastasis in non- small cell lung cancer. Sentinel nodes could be hardly identified in patients with a low ratio of forced expiratory volume in 1 second to forced vital capacity because of such conditions as chronic obstructive pulmonary disease. In vivo identification of sentinel nodes in the mediastinum could be useful approach to guide mediastinal lymph node sampling or dissection.

Adult↗
PubMed1989

Noninvasive evaluation of the swollen extremity: experiences with 190 lymphoscintigraphic examinations.

Lymphoscintigraphy (LS), performed with technetium 99m-labeled antimony trisulfide colloid (Cadema Medical Products, Inc., Middletown, N.Y.), was used as a noninvasive diagnostic examination to evaluate the lymphatic circulation in 190 extremities of 115 patients. Forty-six patients had primary lymphedema, 48 had secondary lymphedema, and 21 patients had other causes of limb swelling. To determine the value of LS in surgical decision making, preoperative and postoperative LS of 16 patients who underwent surgical repair of the lymphatic abnormality were studied separately. Semiquantitative evaluation of the lymphatic drainage and visual interpretation of the image patterns were reliable to differentiate lymphedema from edemas of other origin (sensitivity: 92%, specificity: 100%). Although certain image patterns were characteristic of either primary or secondary lymphedema, LS could not consistently differentiate between the two types. Episodes of cellulitis in lymphedema clearly delayed lymph transport. LS was helpful in patient selection and follow-up after lymphatic surgery, but it did not prove patency of lymphovenous anastomoses. It was diagnostic in the evaluation of lymphangiectasia and was used to document successful surgical treatment of reflux of chyle. LS is safe and reliable and has no side effects. It should replace contrast lymphangiography in the routine evaluation of the swollen extremity.

Adolescent↗
PubMed1997

Ultrasound as a screening study for gastro-oesophageal reflux in children.

A comparison of the abilities of ultrasound and scintigraphy to detect gastro-oesophageal reflux was made in 110 children (mean age 24.5 months) who were divided into groups A (n = 49) and B (n = 61). The former had scintigraphy first followed by ultrasound within about 30 min. For group B scintigraphy was also performed first, but the delay before ultrasound ranged between 1 and 30 days. In most patients (91/110) concordant results were obtained by the two modalities. The 19/110 discordant results can be explained by several plausible mechanisms. It is concluded that ultrasound should be employed much more frequently as an initial investigation when pathological reflux is suspected in children.

Age Distribution↗
PubMed2005

Sentinel lymph node biopsy in oral cancer: validation of technique and clinical implications of added oblique planar lymphoscintigraphy and/or tomography.

PURPOSE: To validate lymphatic mapping combined with sentinel lymph node biopsy as a staging procedure, and to evaluate the possible clinical implications of added oblique lymphoscintigraphy and/or tomography and test the intra- and interobserver reproducibility of lymphoscintigraphy. MATERIAL AND METHODS: Forty patients (17 F and 23 M, aged 32-90) with 24 T1 and 16 T2 squamous cell carcinoma of the oral cavity. Planar lymphoscintigraphy, emission and transmission tomography were performed. Detection and excision of the sentinel nodes were guided by a gamma probe. The sentinel nodes were step-sectioning and stained with hematoxylin and eosin and cytokeratin (CK 1). Histology and follow-up were used as "gold standard". Tumor location, number of sentinel lymph nodes, metastasis, and recurrences were registered. Two observers evaluated the lymphoscintigraphic images to assess the inter-rater agreement. RESULTS: Eleven (28%) patients were upstaged. The sentinel lymph node identification rate was 97.5%. Sentinel lymph node biopsy significantly differentiated between patients with or without lymph node metastasis (P = 0.001). Lymphatic mapping revealed 124 hotspots and 144 hot lymph nodes were removed by sentinel lymph node biopsy. Three patients developed a lymph node recurrence close to the primary tumor site during follow-up. Added oblique lymphoscintigraphic images and/or tomography revealed extra hotspots in 15/40 (38%) patients. In 4/40 (10%), extra contralateral hotspots were detected. CONCLUSION: Sentinel lymph node biopsy upstaged 28% of the patients. Sentinel lymph nodes close to the primary tumor were difficult to find. Added oblique planar images and/or tomographic images revealed extra clinical relevant hotspots in 38% of patients. Reproducibility proved excellent.

Adult↗
PubMed1998

Radiographically negative stress related bone injury. MR imaging versus two-phase bone scintigraphy.

PURPOSE: To assess the diagnostic value of MR imaging relative to two-phase bone scintigraphy in radiographically negative stress-related injuries. MATERIAL AND METHODS: Sixteen consecutive patients presenting with stress-related bone injuries and normal standard radiographs were examined with two-phase bone scans and MR imaging. MR imaging protocols varied according to the region to be examined. The MR and scintigraphic images were evaluated blindly and separately by respectively two radiologists and two nuclear medicine physicians. The standard of reference was represented by a combination of clinical and scintigraphic findings as well as clinical follow-up. RESULTS: For MR imaging, sensitivity, specificity, and positive and negative predictive values for the presence of stress-related injuries for the two readers were 69/63%, 100/80%, 100/91%, and 50/40%, respectively. Interobserver agreement was good (kappa = 0.62). For scintigraphy, all abnormal and normal findings were correctly identified. CONCLUSION: For patients with clinically suspected stress-related injuries and a low probability of other active bone diseases (such as infection or neoplasm), bone scintigraphy should be the initial imaging modality.

Adolescent↗
PubMedDate not supplied

Lymphoscintigraphic technique to image canine esophageal lymph nodes.

Current noninvasive methods of imaging esophageal lymph nodes have an accuracy, specificity, and sensitivity of 70%. Using a flexible esophagoscope, technetium-99m antimony sulfide colloid was injected in the esophageal submucosa of six dogs who then underwent nuclear scans to identify lymph-node location. The euthanized animals underwent dissection of cervical, thoracic, and abdominal lymph nodes. Student's t-test showed no statistical difference in the number of lymph nodes visualized in the neck (3.5 +/- 0.6), parietal thorax (1.2 +/- 0.4), visceral thorax (2.2 +/- 0.7), and abdomen (1.0 +/- 0.0) on premorbid nuclear scans and in the number of radiolabeled lymph nodes found in the neck (3.2 +/- 0.9), parietal thorax (1.2 +/- 0.2), visceral thorax (1.8 +/- 1.0), and abdomen (1.2 +/- 0.2) on dissection of the carcass. The positions of the lymph nodes based on the premorbid nuclear scans matched the locations of the radiolabeled lymph nodes at dissection. Dissected tissue was pathologically confirmed as lymph node. The position and number of lymph nodes in the cervical, intrathoracic, and abdominal regions on nuclear scan correlated with the position and number of lymph nodes found on anatomic dissection. This technique may have a higher sensitivity and specificity than current noninvasive techniques in the staging of esophageal lymphatic metastasis.

Animals↗
PubMed1999

Health effects of sulfur-related environmental air pollution. II. Cellular and molecular parameters of injury.

Recently, concern has been raised about effects related to environmental sulfur and/or acidic aerosols. To assess long-term effects on nonrespiratory lung function, 8 beagle dogs were exposed over a period of 13 mo for 16.5 h/day to a neutral sulfite aerosol at a sulfur(IV) concentration of 0.32 mg m(-3) and for 6 h/day to an acidic sulfate aerosol providing a hydrogen concentration of 15.2 micromol m(-3) for inhalation. Prior to exposure the dogs were kept under clean air conditions for 16 mo to establish physiological baseline values for each animal. A second group of eight dogs (control) was kept for the entire study under clean air conditions. No clinical symptoms were identified that could be related to the combined exposure. Biochemical and cellular parameters were analyzed in sequential bronchoalveolar lavage (BAL) fluids. The permeability of the alveolo-capillary membrane and diethylenetriaminepentaacetic acid (DTPA) clearance was not affected. Similarly, oxidant burden of the epithelial lining fluid evaluated by levels of oxidation products in the BAL fluid protein fraction remained unchanged. Both the lysosomal enzyme beta-N-acetylglucosaminidase and the alpha-1-AT were increased (p <.05). In contrast, the cytoplasmic marker lactate dehydrogenase remained unchanged, indicating the absence of severe damages to epithelial cells or phagocytes. Various surfactant functions were not altered during exposure. Three animals showed elevated levels of the type II cell-associated alkaline phosphatase (AP), indicating a nonuniform response of type II cells. Significant correlations were found between AP and total BAL protein, but not between AP and lactate dehydrogenase, suggesting proliferation of alveolar type II cells. Absolute and relative cell counts in the BAL fluid were not influenced by exposure. Alveolar macrophages showed no alterations with regard to their respiratory burst upon stimulation with opsonized zymosan. The percentage of alveolar macrophages capable of phagocytozing latex particles was significantly decreased (p<.05), while the phagocytosis index was not altered. In view of the results of this and previous studies, we conclude that there is no synergism of effects of these two air pollutants on nonrespiratory lung functions. It is hypothesized that antagonistic effects of these air pollutants on phospholipase A2-dependent pathways account for compensatory physiological mechanisms. The results emphasize the complexity of health effects on lung functions in response to the complex mixture of air pollutants and disclose the precariousness in the risk assessment of air pollutants for humans.

Aerosols↗
PubMedDate not supplied

Is technetium-99 (Tc-99) radiologically significant?

According to radiological protection authorities the radioisotope technetium-99 (Tc-99) is not 'radiologically significant' to humans or other species. The Sellafield plutonium reprocessing plant discharges large amounts of Tc-99 into the Irish Sea; by the year 2015 a total of about 3,000 tera-becquerels of Tc-99, weighing about 5 tonnes, will have been discharged. This article considers the effects of Tc-99 on the environment. After discharge, Tc-99 travels large distances in the ocean. Levels of Tc-99 in Norwegian coastal waters increased by ten times between 1991 and 1996. Tc-99 becomes concentrated offshore in seaweed, winkles and mussels. A concentration factor of 120,000 has been reported in seaweed and one of 650,000 has been measured in the green gland of lobster. It may be necessary to reassess the risk to human health following the ingestion of the relevant isotopes, including Tc-99, because of the possibility of radiation induced genomic instability, as well as the cancer risk. The committed effective doses used to determine permitted levels of intake of these isotopes should be increased and the authorized limits for the discharge of radioactive wastes from Sellafield reduced. Authorized limits of the discharge of radioactivity should be based on Contaminated Food Intervention Levels rather than Generalized Derived Limits as they are now.

England↗
PubMed2000

Pulmonary drug delivery from the Taifun dry powder inhaler is relatively independent of the patient's inspiratory effort.

The Taifun dry powder inhaler (Leiras OY, Turku, Finland) is a breath-actuated, multidose device, each metered dose containing 200 micrograms of budesonide. A two-way randomized crossover gamma scintigraphic study was performed in 10 asthmatic patients to determine the in vivo deposition pattern of budesonide inhaled from the Taifun. In vitro radiolabelling validation studies demonstrated that the radiolabel could be used as an accurate marker to assess in vivo drug deposition. Patients used either maximal inspiratory effort (targeted peak inhalation flow 30 L/min) or submaximal inspiratory effort (targeted peak inhalation flow 15 L/min) on each study day. Mean (S.D.) whole lung deposition (% of metered dose) was 34.3 (5.8)% and 29.6 (5.9)% for the two inhalation flows. The intersubject coefficient of variation in lung deposition was less than 20% on both study days. Drug was deposited uniformly across the central, intermediate, and peripheral lung regions for maximal and submaximal inspiratory efforts. The study suggests that the Taifun is a superior drug delivery device compared with many other inhalers, in terms of the amount of drug deposited in the lungs, the reproducibility of the lung dose, and the relative flow--independence of lung deposition.

Adult↗
PubMed2000

In vitro comparison of sestamibi, tetrofosmin, and furifosmin as agents for functional imaging of multidrug resistance in tumors.

Sestamibi, tetrofosmin, and furifosmin are 99mTc-labeled myocardial perfusion imaging agents which have been shown to be substrates for P-glycoprotein (Pgp), the multidrug-resistance transporter which is overexpressed in some tumors. The three tracers were directly compared in vitro in the human breast cancer cell line MCF7-WT and two multidrug-resistant variants, MCF7-BC19 (MDR1 gene transfected) and MCF7-AdrR (doxorubicin selected). Tracer accumulation over the course of 60 minutes was determined. Dose-response curves were generated for two modulators of Pgp function, GG918 and PSC833. The general shape of accumulation curves for the three tracers in MCF7-WT cells was similar, with accumulation levels being sestamibi > tetrofosmin > furifosmin. Accumulation of sestamibi and furifosmin in MCF7-BC19 cells was reduced to 10% and 21% of MCF7-WT levels, respectively, but this accumulation deficit could be completely reversed by addition of 0.1 microM GG918 or 2 microM PSC833. Accumulation of sestamibi and tetrofosmin in MCF7-AdrR cells was 1.6% and 12% of MCF7-WT levels, respectively, and could only be enhanced to 30% and 45% of MCF7-WT levels by addition of GG918 or PSC833. In contrast, furifosmin showed similar levels of accumulation in MCF7-WT and MCF7-BC19 cells, slightly lower levels in MCF7-AdrR cells, and no consistent response to Pgp modulators. These results support the continued investigation of sestamibi and tetrofosmin as agents for functional imaging of multidrug resistance in human cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2004

Influence of glutathione depletion on plasma membrane cholesterol esterification and on Tc-99m-sestamibi and Tc-99m-tetrofosmin uptakes: a comparative study in sensitive U-87-MG and multidrug-resistant MRP1 human glioma cells.

In our previous studies, we demonstrated a possible effect of cellular glutathione (GSH) depletion on plasma-membrane permeability and fluidity in glioma-cell lines. We therefore investigated the effect of GSH modulation on accumulation of two radiotracers, Tc-99m-sestamibi (MIBI) and Tc-99m-tetrofosmin (TFOS), and on plasma-membrane cholesterol content in sensitive U-87-MG and resistant U-87-MG-CIS and U-87-MG-MEL (MRP1 positive) human glioma-cell lines. GSH depletion was mediated by BSO pretreatment and addition of N-acetylcysteine reversed the effect. MIBI and TFOS uptakes, total cholesterol, and cholesteryl-ester contents were evaluated under each condition. In contrast with TFOS, MIBI accumulation was inversely proportional to the cell multidrug resistance phenotype. Similar cholesterol contents were observed in all cell lines, demonstrating that MRP1 did not modify lipid membrane composition. A decrease of intracellular GSH allows an increase of plasma-membrane cholesterol and a decrease of cholesteryl-ester content, which in turn results in spectacular TFOS uptake. The GSH status of the cells plays an important role in the plasma membrane cholesterol composition and TFOS uptake, which appears to be particularly sensitive to this modification. In contrast with MIBI, TFOS is not an MRP1 probe in glioma cells, and therefore appears to be a suitable tracer in this indication.

Biological Transport↗