technetium-tc-99m-exametazime and Necrosis

The precise localization of bone marrow stem cells (SCs) into the necrotic tissue after intracoronary infusion (ICI) may be important for the therapeutic outcome. This study aims to examine the correlation between Tl-201 and Tc-99m-hexa-methyl-propylene-amine-oxime (HMPAO) images.. Thirteen patients, aged 36-62 years, with an old, nonviable, anterior myocardial infarction (MI) and reduced myocardial contractility (LVEF <40%), underwent ICI of selected CD133(+) and CD133(neg)CD34(+) SCs. One hour after the ICI, SPECT imaging with Tc-99m-HMPAO was performed in all patients and the acquired images were compared with the images obtained during the initial imaging for demonstration of viability (myocardial perfusion imaging with pharmacologic stress and Tl-201). Furthermore, two fused bull's eye images of Tc-99m-HMPAO and Tl-201 rest reinjection were created in six patients and regions of interest were set on Tl-201 and Tc-99m-HMPAO bull's eye images.. The comparison of the two sets of images revealed an intense accumulation of the SCs in the infarcted area with absence of viability as assessed by Tl-201 reinjection images. In the subset of patients in whom fused bull's eye images were produced, the comparison demonstrated that the percentage of the infarcted area with SCs' adherence was 83.2 ± 17%.. Tl-201 images are complementary with the respective Tc-99m-HMPAO ones, revealing a precise localization of SCs in the infarcted area. Tc-99m-HMPAO labeling of SCs is a reliable method for cell monitoring after ICI in nonviable myocardium after an anterior MI.

Topics: Adult; Bone Marrow Cells; Cell Adhesion; Female; Humans; Male; Middle Aged; Myocardial Infarction; Myocardium; Necrosis; Radionuclide Imaging; Retrospective Studies; Stem Cells; Technetium Tc 99m Exametazime; Thallium Radioisotopes; Time Factors

Stem cell tracking is essential for evaluation of its migration, transplantation and therapeutic response. The aim of this study was to evaluate early distribution of intravenously transplanted rat bone marrow mesenchymal stem cells (BMSCs) in rats with acute cerebral trauma by labeling with (99m)Tc-hexamethylpropyleneamine oxime ((99m)Tc-HMPAO).. (99m)Tc-HMPAO-labeled BMSCs were injected intravenously to trauma rats (n=14) and sham-operated controls (n=13). Gamma camera images were acquired at 4 h after injection, and then organs were removed for gamma counting. Confocal microscope was used to confirm the migration of (99m)Tc-BMSCs by co-labeling with PKH26. Cytometric analysis was performed to evaluate apoptotic or necrotic change until the seventh day after labeling.. (99m)Tc-BMSCs were distributed mostly to lungs, liver and spleen at 4 h, and uptake of these organs was not significantly different between traumatic rats and controls. Meanwhile, the cerebral uptake of (99m)Tc-BMSCs was significantly higher in the traumatic rats than in controls (0.40% vs. 0.20%; P=.0002). Additionally, (99m)Tc-BMSCs' uptake of traumatic hemisphere was significantly higher than that of contralateral ones (0.27% vs. 0.13%; P=.0001) in traumatic rats. Regardless of radiolabeling, BMSCs migrated to traumatic regions, but not to nontraumatic hemispheres. However, gamma camera failed to demonstrate (99m)Tc-BMSCs in traumatic hemispheres. No significant apoptotic or necrotic change was observed until 7 days after radiolabeling.. Early distribution of BMSCs in traumatic brain disease could be monitored by (99m)Tc-labeling, which does not induce cellular death. However, our data showed that the amount of migrated (99m)Tc-BMSCs was not enough to be demonstrated by clinical gamma camera.

Topics: Animals; Apoptosis; Brain; Brain Injuries; Case-Control Studies; Female; Fluorescent Dyes; Gamma Cameras; Liver; Lung; Mesenchymal Stem Cells; Microscopy, Polarization; Necrosis; Organic Chemicals; Radionuclide Imaging; Radiopharmaceuticals; Rats; Rats, Sprague-Dawley; Spleen; Technetium Tc 99m Exametazime; Tissue Distribution

In acute pancreatitis (AP), pancreatic necrosis (PN) is an important local complication that can be identified by means of contrast-enhanced computed tomography (CECT). Pancreatic leukocyte infiltration is a significant pathogenic event in the development of PN that can be detected by labeled leukocyte scintigraphy (LLS). The aim of this study was to evaluate the utility of LLS with technetium-99m hexamethylpropylene amine oxime ((99m)Tc-HMPAO) to detect the presence of PN in patients with AP.. Prospective cohort study of 84 patients with AP. Patients underwent LLS and the activity of images was scored on a 0-3 scale. CETC was performed to assess PN. Ranson, Glasgow and APACHE-II scores were calculated. Serum C-reactive protein (CRP) was measured. Sensitivity (Sn), specificity (Sp), positive predictive values (PPV), negative predictive values (NPV), areas under receiver operating characteristic (ROC) curves, likelihood ratios, odds ratios, analysis of variances between groups and correlation coefficients between tests were calculated.. PN was present in 11 (13%) patients. Pancreatic labeled leukocyte uptake was present in 38 patients (45%). Sn, Sp, PPV and NPV of LLS grade 2-3 for PN diagnosis were the highest (91, 88, 53 and 98%, respectively) of all tests. Patients with LLS grade 2-3 were 71 times more likely to be at risk of PN compared to those with LLS grade 0-1. The area under ROC curve of the LLS was the largest. A significant correlation was obtained between LLS and CRP (p < 0.001).. In patients with AP, LLS with (99m)Tc-HMPAO detects PN with an acceptable level of confidence and therefore could be considered an alternative technique to CECT in detecting PN.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; APACHE; C-Reactive Protein; Female; Glasgow Coma Scale; Humans; Leukocytes; Male; Middle Aged; Necrosis; Pancreatitis; Predictive Value of Tests; Prospective Studies; Radionuclide Imaging; ROC Curve; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, X-Ray Computed

Platelets (Plt) accumulate in reperfused myocardium but their effect on myocardial necrosis has not been established. We tested the hypothesis that the effect of Plt depends on their activation status. Pig Plt were obtained before 48 min of coronary occlusion (pre-CO-Plt), 10 min after reperfusion (R-Plt), or after a 60-min sham operation (sham-Plt). Plt were infused into isolated rat hearts (n = 124) and subsequently submitted to 60 min of ischemia and 60 min of reperfusion. P-selectin expression was higher (P = 0.02) in R-Plt than in pre-CO-Plt or sham-Plt. Lactate dehydrogenase (LDH) release during reperfusion was similar in hearts receiving pre-CO-Plt, sham-Plt, or no Plt, but R-Plt increased LDH release by 60% (P = 0.004). Activation of pre-CO-Plt with thrombin increased P-selectin expression and LDH release (P < 0.001), and these results were unaffected by tirofiban. There was a close correlation between P-selectin expression and LDH release (r = 0.84; P < 0.001), and myocardial Plt accumulation (r = 0.85; P < 0.001). We conclude that the deleterious effect of Plt on reperfused myocardium depends on their activation status as represented by P-selectin expression, which is enhanced by ischemia-reperfusion.

Topics: Animals; Blood Platelets; Coronary Disease; Disease Models, Animal; Hemostatics; In Vitro Techniques; Male; Myocardial Infarction; Myocardial Reperfusion Injury; Necrosis; P-Selectin; Platelet Activation; Radionuclide Imaging; Radiopharmaceuticals; Rats; Rats, Sprague-Dawley; Swine; Technetium Tc 99m Exametazime; Thrombin

The prognosis of systemic vasculitis, for instance Wegener's granulomatosis (WG), was greatly improved by the introduction of immunosuppressive treatment. However, relapses are frequent and predictors are scarce. 111In-leukocytes have been found to indicate unknown manifestations of WG and to predict later relapse. We prospectively investigated the value of 99mTc-Exametazime (99mTc-HMPAO)-labeled leukocytes with regard to specific patterns and for their usefulness in the follow-up of patients with WG.. The vasculitis group consisted of 8 patients with WG and 2 with idiopathic necrotizing glomerulonephritis (ING). Seven patients with different inflammatory diseases served as controls. Leukocyte labeling with 99mTc-HMPAO was done using a slightly modified Hammersmith protocol. Cell viability after labeling was verified in vivo by the exclusion of early lung and splenic uptake and in vitro by means of propidium iodide and FACS analysis. Static gamma camera images from the head, chest, abdomen, and pelvis were obtained up to 18 hours after injection of approximately 300 MBq 99mTc-HMPAO-labeled leukocytes. Scintigrams were analyzed visually; for semiquantitative analysis ROIs were drawn over the nasal region, the right lung, kidneys, and liver.. Increased nasal leukocyte accumulation was found in 7/8 patients with WG and in 2/2 patients with ING. Of 2 patients who had a relapse 6 months later, one presented with, and one without nasal uptake. The kidney/liver ratio was higher in controls (0.24 +/- 0.07 vs. 0.37 +/- 0.11, p < 0.05). Distinct to moderate lung uptake was observed in 2 patients with WG and in one with ING. No correlation was found between scintigraphic results, medication, ANCA status or cretinine levels.. Nasal leukocyte accumulation is increased in systemic vasculitis, independent of the immunosuppressive treatment and later clinical course. However, this finding is not specific for vasculitis. 99mTc-HMPAO leukocyte scintigraphy failed to indicate or exclude a later relapse and is therefore not suitable as a diagnostic tool in the management of patients with systemic vasculitis.

Topics: Adult; Aged; Female; Follow-Up Studies; Glomerulonephritis; Granulomatosis with Polyangiitis; Humans; Leukocytes; Male; Middle Aged; Necrosis; Polyarteritis Nodosa; Radionuclide Imaging; Sensitivity and Specificity; Technetium Tc 99m Exametazime

Topics: Abscess; Adult; Humans; Leg Ulcer; Leukocytes; Male; Necrosis; Opioid-Related Disorders; Radionuclide Imaging; Radiopharmaceuticals; Skin; Technetium Tc 99m Exametazime

Clinical and laboratory data or imaging results cannot provide a positive diagnosis of septic complications of pancreatic and peripancreatic necrosis in patients with acute pancreatitis. Confirmation can be obtained only after percutaneous computed tomography (CT)-guided aspiration of the necrotic tissues or fluid collection; although the important role of 99Tc(m)-HMPAO-labeled granulocyte scintigraphy has been recently emphasized. The aim of this study was to determine the sensitivity and specificity of 99m-technetium-hexamethylpropyleneamine oxime (99Tc(m)-HMPAO)- or 111In-oxine-labeled granulocyte scintigraphy for the diagnosis of infection in pancreatic or peripancreatic necrosis to define the ideal label for diagnosis. Thirty-six scintigraphic examinations were performed in 34 consecutive patients (mean age, 58 +/- 2 years) 20 +/- 2 days after the onset of acute pancreatitis (Balthazar classes A-C, n = 7; classes D and E, n = 29). The scintigraphic study included scintigraphic tomography and static acquisition 1 and 3 h, respectively, after reinjection of the autologous 99Tc(m)-labeled granulocytes and static images 3-4 and 24 h after the simultaneous reinjection of 111In-oxine-labeled autologous granulocytes. The diagnosis of infected pancreatic or peripancreatic necrosis was confirmed with percutaneous CT-guided aspiration (14 positive aspirates among 20 performed) and sterile necrosis after negative aspiration (6 negative aspirates) or after a 6 +/- 1-month follow-up free of clinical or biological signs of ongoing sepsis. The sensitivity and specificity were 86 and 73%, respectively, for scintigraphic tomography, 100 and 55% for 3-h 111In images, 93 and 68% for 3-4-h 111In images, and 100 and 64% for 24-h 111In images. The fall in splenic activity between the 3-4 and the 24-h 111In images was 26 +/- 3% in patients with septic pancreatic and peripancreatic necrosis (n = 14) and 16 +/- 3% in those with sterile necrosis (n = 22) (p < 0.01). Labeled granulocyte scintigraphy was thus shown to be an effective tool for the diagnosis of infection in pancreatic and/or peripancreatic necrosis due to acute pancreatitis, especially when the scintiscans are performed early after injection of 99Tc(m) or when the fall in splenic activity over the 24 h following reinjection of 111In is measured in particularly difficult cases. These promising preliminary results should be confirmed by a prospective study.

Topics: Acute Disease; Aged; Female; Granulocytes; Humans; Indium Radioisotopes; Isotope Labeling; Male; Middle Aged; Necrosis; Organometallic Compounds; Organotechnetium Compounds; Oximes; Oxyquinoline; Pancreatitis; Radionuclide Imaging; Sensitivity and Specificity; Sepsis; Technetium Tc 99m Exametazime

We report a case of high uptake of 11C-methionine (MET), 18F-FDG (FDG) and 201Tl-Cl (Tl) in brain radiation necrosis. Twenty-one years previously, the patient had undergone surgery and radiation therapy consisting of 60-Gy for ependymoma in the anterior horn of the right lateral ventricle. The clinical features consisting of frequent seizures of the left face and arm suddenly appeared 2 wk before admission. MRI depicted a Tl and T2-prolonged lesion in the right frontal lobe. Abnormally high uptake in this area demonstrated by MET-PET, FDG-PET, Tl-SPECT or HMPAO-SPECT suggested the presence of a recurrent tumor. A craniotomy was then performed and an intraoperative electrocorticogram showed continuous epileptic spikes in the lesion. The epileptic foci were resected and the histological features of the lesion were consistent with radiation necrosis. After surgery, the seizures disappeared and the postoperative examinations with MET-PET, FDG-PET, Tl-SPECT and HM-PAO-SPECT no longer showed abnormally high uptake. Hypermetabolism and hyperperfusion related to epileptic fits are therefore thought to result in high uptake of MET, FDG and Tl in radiation necrosis.

Topics: Adult; Brain; Brain Neoplasms; Deoxyglucose; Ependymoma; Epilepsy, Frontal Lobe; Female; Fluorine Radioisotopes; Fluorodeoxyglucose F18; Humans; Methionine; Necrosis; Organotechnetium Compounds; Oximes; Radiation Injuries; Technetium Tc 99m Exametazime; Thallium Radioisotopes; Time Factors; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

SPECT scanning with Tl-201 and Tc-99m offers a unique, inexpensive functional imaging modality to combine with CT stereotactic craniotomy for guiding resection of necrosis and/or tumour in patients treated with escalated doses of radiation (> 6000 cGy) by either brachytherapy or radiosurgery. Thirty-two cases were analyzed, with a detailed description of the imaging and operative techniques.

Topics: Astrocytoma; Brachytherapy; Brain; Brain Neoplasms; Combined Modality Therapy; Cranial Irradiation; Craniotomy; Follow-Up Studies; Glioma; Humans; Image Processing, Computer-Assisted; Necrosis; Neoplasm Recurrence, Local; Organotechnetium Compounds; Oximes; Radiation Injuries; Radiosurgery; Radiotherapy Dosage; Reoperation; Software; Stereotaxic Techniques; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

The infiltration of leukocytes has been linked to the pathophysiology of complicated or severe pancreatitis. We have tested the ability of leukocyte scintigraphy using technetium-99m-hexamethyl propylene amine oxine (HM-PAO) as label to demonstrate the localization of leukocytes in the pancreas during acute pancreatitis. Twenty-eight patients with acute pancreatitis (eight with biliary, 13 with alcoholic, and seven with unknown origin) were studied with leukocyte scintigraphy using planar imaging and single photon emission computed tomography (SPECT). Fourteen patients had a mild (group I), II a severe (group II), and three a lethal outcome (group III) of pancreatitis. All patients of group III, six of group II, and two of group I had a positive leukocyte scan. Thus, the sensitivity of leukocyte scintigraphy for the detection of a lethal course of acute pancreatitis was 100%, of a severe course 54%, and of a severe or lethal course 64%. The specificity of a negative scan for a mild pancreatitis was 86%. Comparison of the results of leukocyte scintigraphy with those of contrast enhanced CT showed that six of eight patients with pancreatic necrosis in CT had a positive leukocyte scan, but only five of 20 patients without detectable pancreatic necrosis in CT. In summary, leukocyte infiltration into the pancreas during pancreatitis can be demonstrated by noninvasive leukocyte scintigraphy using technetium-99m-HM-PAO as label. A correlation between the severity of the disease and leukocyte infiltration exists.

Topics: Acute Disease; Adult; Aged; Cell Movement; Female; Humans; Leukocytes; Male; Middle Aged; Necrosis; Organotechnetium Compounds; Oximes; Pancreas; Pancreatic Elastase; Pancreatitis; Radiographic Image Enhancement; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Tc-99m hexamethylpropylene amineoxime (HMPAO) is a novel radiopharmaceutical demonstrated to be a sensitive indicator of abnormalities of cerebral perfusion. Most reports in the literature have evaluated patients with gross perfusion deficits, such as cerebrovascular accidents, and with dementia, where patterns of diffuse perfusion deficit were reported comparable with those seen in PET studies. We report a patient in whom there was the rapid onset of dementia, with the HMPAO images demonstrating diffuse loss of cortical perfusion in a nonfocal, and nonsegmental, fashion. Correlation with postmortem examination demonstrates good concordance between the diffuse nature of HMPAO loss, and diffuse cortical necrosis throughout both cerebral hemispheres. The technique was shown to be more sensitive than transmission CT scanning in demonstrating the extent of the deficit, and it correlated closely with the functional deficits noted in the patient.

Topics: Acute Disease; Brain; Cerebral Cortex; Cerebrovascular Circulation; Dementia; Humans; Male; Middle Aged; Necrosis; Organotechnetium Compounds; Oximes; Radionuclide Imaging; Technetium Tc 99m Exametazime