Scintigraphic abscess localization with 99mTc-labeled leukocytes as compared to 67Ga citrate

Social functioning of 40 depressed women was studied four years following the acute episode, and compared with 40 normal community subjects. Results show that the social impairments of depressed patients persist well beyond the acute episode, particularly in marital and close interpersonal relations. Clinical and public health implications are discussed.     

Scintigraphic evaluation of malignant melanoma lesions with Tc-99m tetrofosmin

Two cases of malignant melanoma (primary and metastatic lesions) imaged with Tc-99m tetrofosmin are reported. One patient showed intense uptake in a primary skin lesion of the thorax, and the other patient had accumulation in skin, cerebellum, breast, and lymph node metastases. Like Tc-99m MIBI, Tc-99m tetrofosmin imaging may be of clinical relevance in the evaluation of suspicious skin lesions and in patients with known cutaneous malignant melanoma in the assessment of recurrent disease during follow-up evaluation.     

Primary lung cancer associated with diffuse granulomatous lesions in the pulmonary parenchyma

A 60-year-old man was admitted to our hospital for productive cough. Chest roentgenography and CT scan disclosed a left hilar tumor invading the mediastinum, with mediastinal lymphadenopathy and diffuse micronodular shadows in both lung fields. A biopsied sample of the tumor revealed squamous cell carcinoma, while noncaseating epithelioid cell granulomas were observed in the samples obtained by transbronchial lung biopsy. The granulomas in the pulmonary parenchyma were determined to be sarcoid reactions secondary to lung cancer, since there was no evidence of sarcoidosis. Combination chemotherapy was effective for the tumor, and the granulomas disappeared after completion of the chemotherapy. These findings suggest the presence of a relationship between sarcoid reactions and lung cancer in this case.     

Scintigraphic evaluation of experimental colitis in rabbits

Scintigraphic techniques are frequently used for evaluation of inflammatory bowel disease. The radiopharmaceutical of choice is labeled leukocytes. In this study, two new agents, 111In-labeled polyethylene glycol-coated liposomes and 111In-labeled human nonspecific gamma globulin (immunoglobulin G; IgG), were compared with 111In-leukocytes in a rabbit model of colitis. METHODS: In rabbits, acute colitis was induced by colonic instillation of trinitrobenzene sulfonic acid at 25 cm from the anal sphincter. After 24 hr, 15 MBq of the radiopharmaceuticals was injected intravenously in groups of four rabbits. Twenty-four hours after injection, the animals were killed and macroscopic abnormalities were scored in seven consecutive affected colonic segments of 5 cm each (0 = normal, 1 = inflammation, 2 = ulcers). The ex vivo uptake was measured in the normal ascending colon and the affected colonic segments. The colitis index (CI, affected-to-normal colon-uptake ratio) was calculated. RESULTS: Histologically, an acute, patchy, transmural colitis was observed at the site of instillation and the distal colon. The CI of all agents in colitis lesions correlated with the severity of the abnormalities. With increasing severity, the CI for liposomes was 1.86 +/- 0.24, 4.88 +/- 0.42 and 7.42 +/- 0.54 (r2 = 0.68, p < 0.001); for leukocytes 1.77 +/- 0.32, 3.10 +/- 0.58 and 5.54 +/- 0.83 (r2 = 0.31, p < 0.01); for IgG 1.60 +/- 0.29, 2.81 +/- 0.21 and 2.65 +/- 0.21 (r2 = 0.29, p < 0.02). CONCLUSION: Indium-111-labeled-leukocytes, -IgG and -liposomes all show increased uptake in inflamed colonic tissue. Indium-111-liposomes showed the highest CI, which correlates best with the morphological abnormalities. Indium-111-leukocytes and 111In-liposomes are superior to 111In-IgG for this indication.     

Scintigraphic visualization of pulmonary thrombi with 123I-YPACK-TNK-tPA

BACKGROUND: We have previously demonstrated that radiolabeled tissue-type plasminogen activation (tPA) in which the plasminogen-activating catalytic site has been inactivated binds avidly to thrombi and can be used for scintigraphic detection of pulmonary thrombi in vivo. The present study was performed to overcome identified limitations of the initially developed approach and to determine whether a tracer made with a molecular variant of tPA, TNK-tPA, would provide superior images of pulmonary thrombi and hence facilitate differential diagnosis of pulmonary embolism from acute myocardial infarction. It was thought that TNK-tPA may be superior in view of its longer biological half-life and less avid uptake by macrophages that would otherwise contribute to high background because of non-clot-selective uptake of the tracer. METHODS: 123I-tyrosylprolylarginyl chloromethyl ketone (123I-YPACK-TNK-tPA) was infused into the systemic circulation of dogs with either pulmonary or right ventricular thrombi induced with thrombogenic tips of modified guide wires. Planar and single-photon emission computed tomography (SPECT) scintigraphic data were obtained, and blood and tissue samples were acquired for analysis of the distribution of the radiotracer over time. RESULTS: Tracer cleared from blood with an alpha phase half-life of 10 +/- 1 min, paralleling the clearance of unlabeled TNK-tPA. Only minimal release of labeled fragments from liver into blood occurred during the entire time course of the imaging studies. Pulmonary thrombi were visualized with SPECT within 30-120 min in all dogs. Images were superior to those obtained after infusion of labeled wild-type tPA, primarily because of diminished background radioactivity and consequently increased scintigraphic contrast. In one dog which had a right ventricular thrombus, the thrombus was readily detectable in both planar and SPECT images. CONCLUSIONS: Radiolabeled TNK-tPA in which plasminogen-activating activity has been inhibited biochemically is an excellent radiopharmaceutical for prompt scintigraphic detection of pulmonary and ventricular thrombi in vivo, and an attractive candidate for rapid, sensitive and non-invasive diagnosis of pulmonary thromboembolic disease in patients.     

Localization of gallium-67 citrate in salivary glands following radiation therapy

Gallium-67 citrate was found to localize in the salivary glands of eight patients after therapeutic doses of radiation to a treatment field including the glands. In two patients, autopsy evidence to the effect that no primary disease was present to explain such uptake was obtained. In another two patients the abnormal uptake was not observed on follow-up. The recognition that radiation sialadenitis is a potential cause of false-positive gallium scintiscans is important in their interpretation.     

Gallium citrate Ga 67 scanning: clinical usefulness in lymphoma patients

Gallium citrate Ga 67 (67Ga) scans were performed in 50 consecutive lymphoma patients who underwent routine staging. The overall accuracy of 67Ga scans was greater than 80% for all nodal sites except the spleen (68%). Sensitivity was greater than 88% in the neck and mediastinum, 67% in the abdomen-pelvis, and 33% for the spleen. Specificity was greater than 85% for all nodal sites except for the mediastinum (67%). The accuracy of pedal lymphangiograms was 75%, sensitivity 87%, and specificity 68%. Gallium 67 scans complemented the lymphogram in the abdomen-pelvis but, due to limited sensitivity and high number of equivocal studies (16%), did not replace it. Infraclavicular, pectoral, and mediastinal lesions were detected by 67Ga scans when missed by other means. In 20% to 25% of patients, 67Ga scans provided information not afforded by other diagnostic studies and are therefore considered an important staging procedure for lymphoma patients.     

Pathogenic mechanisms in the development of diffuse pulmonary fibrosis

Diffuse pulmonary fibrosis is characterized by abnormal proliferation of mesenchymal cells, specifically fibroblasts and myofibroblasts, and by the accumulation of excessive amounts of matrix proteins, mainly collagens. The development of this pathological process is preceded by an inflammatory response, often dominated by macrophages and lymphocytes, which is mediated by the local release of chemoattractant factors, acting coordinately with an upregulation of cell-surface adhesion molecules. A subsequent persisting fibroproliferative reaction, in both interstitial and intraalveolar spaces, with progressive collagen accumulation distorts the lung architecture irreversibly. Excessive collagen deposition is the result of an imbalance in the collagen turnover rates characterized by a transient increase in collagen synthesis and a decrease in collagen degradation. Fibrosis is considered otherwise to be the final common pathway of a variety of lung disorders, and in this context, the diagnosis of pulmonary fibrosis implies the recognition of an advanced stage in the evolution of a complex process of abnormal repair.     

Scintigraphic evaluation of disorders of the esophagus, stomach, and duodenum

Gastrointestinal nuclear medicine procedures have progressed from the stage of anatomic imaging alone to their present applications in studying gastrointestinal function and pathophysiology. These tracer techniques have several specific advantages over other procedures. Scintigraphy requires no intubation, has excellent patient acceptance, is quantitative, and delivers lower radiation burdens to the patient than does the contrast radiographic study. Currently, nuclear medicine functional scintigraphy in gastroenterology is being applied clinically in many medical centers throughout the world.     

Scintigraphy with gallium-67 citrate in patients with AIDS: pathologic extrapulmonary uptake

67Gallium citrate can accumulate in different inflammatory and neoplastic lesions. The mechanisms of 67Gallium uptake in abnormal tissue are still partially unknown and the tracer is considered a nonspecific indicator of disease. In AIDS patients, 67Gallium citrate is used in the diagnosis and characterization of opportunistic pulmonary infections and especially of Pneumocystis carinii pneumonia. From June 1989 through December 1992 in our Department 140 67Gallium scans were performed on 103 AIDS patients, referred for evaluation of pulmonary symptoms. All studies were carried out 72 hours after i.v. administration of 185 MBq 67Gallium citrate, with anterior and posterior views of head, chest and abdomen. The images were evaluated with conventional diagnostic criteria and site, number and intensity of abnormal foci of extrapulmonary uptake were recorded. Abnormal extrapulmonary uptake was found in 17 patients (12%): gastric (3, two of which also exhibited abnormal intestinal uptake), esophageal (1) hepatic (1), intestinal (2) renal (4), nodal (3), ocular (1), cutaneous (1), sinusal (1) localizations. In all cases clinical, endoscopic, bioptic or microbiological demonstration of the possible cause of 67Gallium uptake was obtained. An intriguing finding in our series was the lower incidence of gastric uptake (two patients with miliary tuberculosis and one patient with gastric candidiasis) than in the literature. This finding could be explained by clinical and epidemiologic differences between different patient populations. However, the scan interval after tracer administration should be also taken into account, since in our study scans were always performed at 72 hours, while in other series the interval ranged 24-48 hours. The relatively high incidence of abnormal extrapulmonary uptake confirms the opportunity of whole body exploration after 67Gallium administration in the patients with such multisystemic disease as AIDS, even when the patients are referred mainly for respiratory problems.     

Scintigraphic imaging of pituitary adenomas: an in vivo evaluation of somatostatin receptors

We have performed pituitary scintigraphy with the somatostatin (SS) analog pentetreotidean by (111In-P) in patients with GH-secreting adenoma or with "clinically non functioning" adenoma (NFA) to evaluate the presence and the functionality of SS receptors (SS-R). 111In-P pituitary accumulation was expressed as Activity Ratio (AR): the ratio between the uptake of radioactivity by the adenoma and that of the normal brain tissue. In subjects without pituitary disease, AR ranged from 1.6 to 2.2 and a value lower than 2.2 was thus arbitrarily considered as normal. In 15 out of the 17 patients with GH-secreting adenoma, an accumulation of the radioligand was shown. Median AR was 3.8 (range 1-6.9; in 14 AR were greater that 2.2) and ARs were directly correlated (r = 0.54; p < 0.05) with the suppressibility of plasma GH levels by octreotide (OC) acute administration. In two patients who repeated scintigraphy during chronic OC treatment, AR values were reduced. In all the 22 patients with NFA an accumulation of 111In-P at the pituitary level was observed and median AR was 3.0 (range 1.5-20; in 14 greater that 2.2). In vitro autoradiography of surgical specimens in 6 NFA patients revealed SS-R in 4 cases with high scintigraphic AR and negative results in two cases with low AR. Scintiscan was repeated during chronic OC treatment in 5 patients with high score: AR decreased in one patient, increased in three, and did not change in the other patient. No changes in tumor size were shown in any of these patients. A total of 8 patients (3 GH secreting and 5 NFA) had "normal" AR values. CONCLUSIONS: In acromegaly scintigraphy with 111In-P visualizes functioning pituitary SS-R coupled to intracellular events that control hormonal hypersecretion and tumor growth. In contrast, in spite of the positivity of 111In-P imaging in most patients with NFA, their receptors might have a defect in the coupling-transduction process, as they are not inhibited by OC treatment and no tumor shrinkage is observed.     

The study on noninvasive evaluation of pulmonary artery pressure by the method of pulmonary artery flow spectrum in chronic pulmonary disease

OBJECTIVE: Pulmonary artery flow spectrum of patients with chronic pulmonary disease were studied in order to find excellent Doppler Indexes reflected pulmonary artery pressure, and establish multiple regression equation for estimating pulmonary artery pressure more accurately. METHODS: During catheterization, 54 patients with chronic pulmonary disease were examined by echocardiography. Fourteen Doppler indexes of spectrum were compared with the pulmonary artery pressure by catheter simultaneously, and multiple regression equations were taken. RESULTS: There were significant correlation between Doppler indexes PEP/AcT, AcVm, VI/(QTxVmax), RVET/QT and pulmonary artery pressure. Two multiple regression equations were deduced: PAPs (kPa) = [9.4 x PEP/AcT-1.4 x AcVm-126.1 x VI/(QT x Vmax) + 75] divided by 7.5 and PAPm (kPa) = [7.5 x PEP/AcT-1.2 x AcVm- 87.7 x VI/(QT X Vmax) + 48] divided by 7.5. CONCLUSIONS: Above two regression equations could be used to noninvasively evaluate pulmonary artery pressure in patients with chronic pulmonary disease.     

Nuclear cardiology, Part III: Scintigraphic evaluation of cardiac perfusion

OBJECTIVE: After reading Part III of this series of nuclear cardiology articles, the technologist should be able to: (a) compare and contrast radiopharmaceuticals used for myocardial perfusion imaging; (b) describe imaging protocols used for detecting coronary artery disease; and (c) describe imaging patterns seen following reconstruction of myocardial images.     

Scintigraphic diagnosis of syphilitic lesions in rabbits by radiolabelled monoclonal antibodies specific for Treponema pallidum

Immunoscintigraphy with radiolabelled monoclonal antibodies has been widely used to detect solid tumours. The purpose of this study was to investigate its potential for the specific localization of syphilitic lesions. F(ab')2 fragments were prepared from murine monoclonal antibodies against Treponema pallidum produced in our laboratory and labelled with 131I. Bilateral testicular infections were created in rabbits by inoculation with T. pallidum or Staphylococcus aureus. Seven to 10 days after inoculation, radiolabelled antibodies were injected intravenously. Serial gamma images were then taken 2 h after the injection and at 24 h intervals thereafter. Beginning as early as 2 h post-injection, the testicles could be visualized with either specific or non-specific antibodies. Gamma images in the monoclonal antibody-treated, T. pallidum-infected group persisted up to 48 h post-injection. Lesions were not discernible from background in the S. aureus-infected group injected with the monoclonal antibody and the S. aureus-infected and T. pallidum-infected groups injected with the polyclonal antibody at 24 h post-injection or later. Therefore, due to its ability to differentiate between specific and non-specific antibody-generated images from 24 h post-injection, immunoscintigraphy using monoclonal antibodies specific for T. pallidum may be employed as one of the methods to diagnose difficult cases of syphilitic internal organ involvement as well as syphilis infection in seronegative HIV-infected patients.     

A diffuse form of pulmonary silicosis in foundry workers

Pulmonary silicosis usually is characterized by typical hyalinized, concentric nodules as seen under the microscope and in the corresponding roentgenogram. In the case of three foundry workers, lung biopsy specimens contained no nodules. The chest roentgenograms were not suggestive of silicosis. Examination of the biopsy tissue by scanning electron microscopy and energy dispersive x-ray analysis (EDXA) revealed significant (P less than .05) amounts of silicon in the thickened fibrous tissues of septa, pleura, and around blood vessels, enough to permit the diagnosis of silicosis. All three patients had severe functional impairment. It is not clear at this time what factors were responsible for a diffuse distribution of silicon in these cases.     

模糊综合评判在学校评估中的应用

学校整体管理工作受多种因素的影响 ,文章将评估中所涉及的因素看作模糊因素 ,应用模糊数学的综合评估方法建立了学校整体办学水平综合评估体系 .