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Sample records for 99m tc-hmpao spect

  1. Brain energy metabolism in Alzheimer's disease: 99mTc-HMPAO SPECT imaging during verbal fluency and role of astrocytes in the cellular mechanism of 99mTc-HMPAO retention.

    PubMed

    Slosman, D O; Ludwig, C; Zerarka, S; Pellerin, L; Chicherio, C; de Ribaupierre, A; Annoni, J M; Bouras, C; Herrmann, F; Michel, J P; Giacobini, E; Magistretti, P J

    2001-10-01

    photon emission computed tomography (SPECT) imaging, has been studied in vitro in purified preparations of neurons and astrocytes with the aim of investigating the contribution of different cell types to hexamethyl-propyleneamineoxime labeled with technetium-99m (99mTc-HMPAO) retention in vitro. Results show that 99mTc-HMPAO retention predominates in astrocytes over neurons by a factor of approximately 2.5. Diethyl maleate, ethacrynic acid and buthionine sulfoximine, three agents which significantly reduce glutathione levels, also decreased 99mTc-HMPAO retention in both astrocytes and in neurons. Decrease did not always correlate with glutathione levels however, thus suggesting that other factors could be involved. The data presented indicate that astrocytes might constitute a prominent site of 99mTc-HMPAO retention and most likely contribute significantly to the SPECT signal. In addition, they also suggest that specific alterations in glial cell metabolism could explain flow-independent changes in 99mTc-HMPAO retention in the brain as observed by SPECT in certain pathologies (including Alzheimer's disease). In particular, these observations suggest a key role of astrocytes in the signal detected with the imaging procedure, which is altered in the Alzheimer's cohort subjected to the verbal fluency activation task. PMID:11690620

  2. Anticardiolipin antibodies in HIV infection: association with cerebral perfusion defects as detected by 99mTc-HMPAO SPECT.

    PubMed Central

    Rubbert, A; Bock, E; Schwab, J; Marienhagen, J; Nüsslein, H; Wolf, F; Kalden, J R

    1994-01-01

    Anticardiolipin antibodies (ACA) belong to a heterogeneous group of antibodies directed against negatively charged phospholipids. In patients with rheumatic disorders, their presence has been correlated to the occurrence of thromboembolic complications, thrombocytopenia, abortions and other disease manifestations. Several studies have revealed the detection of mostly high-titre ACA in a significant proportion of HIV-infected patients without any known clinical relationship. In our study, ACA were detected in 17/34 HIV-infected patients, and their presence was significantly associated with the detection of cerebral perfusion abnormalities by 99mTc-HMPAO SPECT. SPECT scans were classified as normal or as focal or diffuse defects in uptake. Most patients (13/16) with cerebral perfusion defects had elevated ACA titres in contrast to 4/18 patients with normal SPECT findings (P = 0.002). Focal uptake defects were always associated with the presence of ACA. No correlation to clinical features or other laboratory parameters was evident. Our results suggest a possible implication of autoimmune mechanisms in the pathogenesis of cerebral perfusion abnormalities detected by SPECT scanning in HIV-infected patients. However, further studies are needed to evaluate the clinical significance and to develop possible therapeutic consequences. Images Fig. 1 Fig. 2 Fig. 3 PMID:7994900

  3. Noninvasive imaging of radiolabeled exosome-mimetic nanovesicle using (99m)Tc-HMPAO.

    PubMed

    Hwang, Do Won; Choi, Hongyoon; Jang, Su Chul; Yoo, Min Young; Park, Ji Yong; Choi, Na Eun; Oh, Hyun Jeong; Ha, Seunggyun; Lee, Yun-Sang; Jeong, Jae Min; Gho, Yong Song; Lee, Dong Soo

    2015-01-01

    Exosomes known as nano-sized extracellular vesicles attracted recent interests due to their potential usefulness in drug delivery. Amid remarkable advances in biomedical applications of exosomes, it is crucial to understand in vivo distribution and behavior of exosomes. Here, we developed a simple method for radiolabeling of macrophage-derived exosome-mimetic nanovesicles (ENVs) with (99m)Tc-HMPAO under physiologic conditions and monitored in vivo distribution of (99m)Tc-HMPAO-ENVs using SPECT/CT in living mice. ENVs were produced from the mouse RAW264.7 macrophage cell line and labeled with (99m)Tc-HMPAO for 1 hr incubation, followed by removal of free (99m)Tc-HMPAO. SPECT/CT images were serially acquired after intravenous injection to BALB/c mouse. When ENVs were labeled with (99m)Tc-HMPAO, the radiochemical purity of (99m)Tc-HMPAO-ENVs was higher than 90% and the expression of exosome specific protein (CD63) did not change in (99m)Tc-HMPAO-ENVs. (99m)Tc-HMPAO-ENVs showed high serum stability (90%) which was similar to that in phosphate buffered saline until 5 hr. SPECT/CT images of the mice injected with (99m)Tc-HMPAO-ENVs exhibited higher uptake in liver and no uptake in brain, whereas mice injected with (99m)Tc-HMPAO showed high brain uptake until 5 hr. Our noninvasive imaging of radiolabeled-ENVs promises better understanding of the in vivo behavior of exosomes for upcoming biomedical application. PMID:26497063

  4. Noninvasive imaging of radiolabeled exosome-mimetic nanovesicle using 99mTc-HMPAO

    PubMed Central

    Hwang, Do Won; Choi, Hongyoon; Jang, Su Chul; Yoo, Min Young; Park, Ji Yong; Choi, Na Eun; Oh, Hyun Jeong; Ha, Seunggyun; Lee, Yun-Sang; Jeong, Jae Min; Gho, Yong Song; Lee, Dong Soo

    2015-01-01

    Exosomes known as nano-sized extracellular vesicles attracted recent interests due to their potential usefulness in drug delivery. Amid remarkable advances in biomedical applications of exosomes, it is crucial to understand in vivo distribution and behavior of exosomes. Here, we developed a simple method for radiolabeling of macrophage-derived exosome-mimetic nanovesicles (ENVs) with 99mTc-HMPAO under physiologic conditions and monitored in vivo distribution of 99mTc-HMPAO-ENVs using SPECT/CT in living mice. ENVs were produced from the mouse RAW264.7 macrophage cell line and labeled with 99mTc-HMPAO for 1 hr incubation, followed by removal of free 99mTc-HMPAO. SPECT/CT images were serially acquired after intravenous injection to BALB/c mouse. When ENVs were labeled with 99mTc-HMPAO, the radiochemical purity of 99mTc-HMPAO-ENVs was higher than 90% and the expression of exosome specific protein (CD63) did not change in 99mTc-HMPAO-ENVs. 99mTc-HMPAO-ENVs showed high serum stability (90%) which was similar to that in phosphate buffered saline until 5 hr. SPECT/CT images of the mice injected with 99mTc-HMPAO-ENVs exhibited higher uptake in liver and no uptake in brain, whereas mice injected with 99mTc-HMPAO showed high brain uptake until 5 hr. Our noninvasive imaging of radiolabeled-ENVs promises better understanding of the in vivo behavior of exosomes for upcoming biomedical application. PMID:26497063

  5. Preliminary findings of simultaneous 18F-FDG and 99mTc-HMPAO SPECT in patients with depressive disorders at rest: differential correlates with ratings of anxiety.

    PubMed

    Conca, A; Fritzsche, H; Peschina, W; König, P; Swoboda, E; Wiederin, H; Haas, C

    2000-02-28

    The assumption of a dynamic coupling between regional cerebral blood flow (rCBF) and cerebral glucose metabolic rates (rCMRGlu) has been challenged by simultaneous measurements of both. Through the use of a dual-headed gamma camera with a 511-keV collimator applying the double isotope 18F-FDG and 99mTc-HMPAO SPECT technique, the uptake rates of these isotopes can be semi-quantitatively evaluated. Sixteen depressed patients, diagnosed by ICD-10 criteria and assessed with the 17-item Hamilton Rating Scale for Depression (HRSD), were studied. Based on the severity of HRSD-rated anxiety (item 10: low=1-21; high=3-4), two eight-patient subgroups were formed and compared with 12 age- and handedness-matched healthy control subjects. As regions of interest, we selected areas implicated in the neuroanatomy of anxiety and depression: hippocampus (hippo), basal ganglia (BG) and gyri temporales superiores (G.t.s.). In the control subjects, a significant statistical coupling between rCBF and rCMRGlu was revealed by the Spearman correlation coefficient only in left hippo and left BG. Patients in the low-anxiety subgroup demonstrated a marked dynamic coupling bilaterally for the G.t.s., while patients in the high-anxiety subgroup showed a significant statistical correlation of rCBF and rCMRGlu only in the left G.t.s. These findings indicate that a dynamic coupling between blood flow and glucose metabolism exists only in distinct brain regions, and that the depressive illness has an uncoupling effect on this correlation in the left BG. Furthermore, our results suggest that the HRSD anxiety score might interact with the underlying depressive illness to influence the relationship of rCBF and rCMRGlu. PMID:10708925

  6. Bilateral alien hand syndrome in cerebrovascular disease: CT, MR, CT angiography, and 99mTc-HMPAO-SPECT findings.

    PubMed

    Serrano-Vicente, Justo; Duran-Barquero, Carmen; Garcia-Bernardo, Lucia; Dominguez-Grande, Maria Luz; Infante-Torre, Jose Rafael; Rayo-Madrid, Juan Ignacio

    2015-03-01

    We report a 65-year-old man with a right cerebral infarction that occurred 15 years ago and a residual left hemiparesis that began with progressive contralateral hemiparesis. During the hospitalization, the patient developed a bilateral alien hand syndrome. Urgent CT, MR, CT angiography, and brain perfusion SPECT were performed that revealed an old right cerebral infarction and a new ischemic lesion in left parietal lobe and adjacent brain territories. PMID:25546190

  7. Nano Liposomes Labeled with 99mTc-HMPAO, a Novel Agent for Blood Pool Imaging

    PubMed Central

    Sadri, Kayvan; Momenypoor, Salimeh; Dabbagh Kakhki, Vahid Reza; Sadeghi, Ramin; Aryana, Kamran; Johari Daha, Fariba; Zakavi, Seyed Rasoul; Jaafari, Mahmoud Reza

    2015-01-01

    In-vitro labeling of RBC with 99mTc is an intricate procedure and there is always a need for an alternate blood pool imaging agent. The aim of this study was to prepare an effective nano sized liposome (NLs) similar to human RBC for blood pool scintigraphy. This study formulates PEG-NLs and non-PEG-NLs using film method plus high pressure homogenization technique. Biodistribution studies were performed on BALB/C mice 1, 4 and 24 h after tail vein injection of labeled NLs with 99mTc hexamethylpropylene-amine-oxime (99mTc-HMPAO). Planar images were acquired using a 256 × 256 matrix following99m Tc-HMPAO-NLs injection into ear vein of rabbits 1, 2 and 24 h later. SPECT images were obtained 15 minutes after the injection (64 slices, 30 second/projection). The mean diameter, zeta potential and polydispersity index (PDI) of the PEG-NLs and the NLs were (80.88 ± 0.594 nm, -12.5 ± 0.56 mv, 0.158 ± 0.025) and (94.14 ± 0.114 nm, -35.5 ± 0.67 mv and 0.198 ± 0.007), respectively. 99mTc-HMPAO-PEG-NLs showed a significant circulation tracer activity (7.74 ± 1.63%ID/g at 1 h and 4.9 ± 0.77 %ID/g at 4 h), with low liver accumulation (12.07 ± 3.66 %ID/g at 1 h and 14.85 ± 1.3 %ID/g at 4 h). Heart to liver, spleen and background ROIs (region of interests) for 99m Tc-HMPAO-PEG-NLs were 1.25, 4 and 4.28 respectively at 2 h which changed to 1.06, 1.75 and 2.51 respectively at 24 h. The 99mTc-HMPAO-PEG-NLs with a prolonged blood circulation time could be an excellent RBC alternative for scintigraphy and gastrointestinal bleeding. PMID:26664365

  8. Role of Brain Perfusion SPECT with 99mTc HMPAO in the Assessment of Response to Drug Therapy in Patients with Autoimmune Vasculitis: A Prospective Study

    PubMed Central

    Mauro, Liberatore; Manuela, Morreale; Valentina, Megna; Sara, Collorone; Chondrogiannis, Sotirios; Maria, Drudi Francesco; Christos, Anagnostou; Liana, Civitelli; Ada, Francia; Maffione, Anna Margherita; Marzola, Maria Cristina; Rubello, Domenico

    2015-01-01

    Background: The diagnosis of vasculitis in the brain remains a quite difficult achievement. To the best of our knowledge, there is no imaging method reported in literature which is capable of reaching to a diagnosis of vasculitis with very high sensitivity. Aim: The aim of this study was to determine whether perfusion brain single photon emission computed tomography (SPECT) can be usefully employed in monitoring the treatment of vasculitis, allowing treating only potentially responder patients and avoiding the side effects on patients who do not respond. Materials and Methods: Twenty patients (two males and 18 females) suffering from systemic lupus erythematosus (SLE; n = 5), Behcet's disease (BD; n = 5), undifferentiated vasculitis (UV; n = 5), and Sjogren's syndrome (SS; n = 5) were included in the study. All patients underwent a wide neurological anamnestic investigation, a complete objective neurological examination and SPECT of the brain with 99mTc-hexamethyl-propylene-aminoxime (HMPAO). The brain SPECT was then repeated after appropriate medical treatment. The neurological and neuropsychiatric follow-up was performed at 6 months after the start of the treatment. Results: Overall, the differences between the scintigraphic results obtained after and before the medical treatment indicated a statistically significant increase of the cerebral perfusion (CP). In 19 out of 200 regions of interest (ROI) studied, the difference between pre- and post treatment percentages had negative sign, indicating a worsening of CP. This latter event has occurred six times (five in the same patients) in the UV, 10 times (eight in the same patients) in the SLE, never in BD, and three times (two in the same patient) in the SS. Conclusion: The reported results seem to indicate the possibility of identifying, by the means of a brain SPECT, responder and nonresponder (unchanged or worsened CP) patients, affected by autoimmune vasculitis, to the therapy. PMID:25973400

  9. Diagnosis of pyogenic pelvic inflammatory diseases by 99mTc-HMPAO leucocyte scintigraphy.

    PubMed

    Rachinsky, I; Boguslavsky, L; Goldstein, D; Golan, H; Pak, I; Katz, M; Lantsberg, S

    2000-12-01

    Pelvic inflammatory disease (PID) is one of the major health problems of women of child-bearing age. Among the most serious complications of PID is the formation of a tubo-ovarian abscess (TOA). Early diagnosis of this condition may prevent serious surgical complications such as peritonitis and sepsis, which may be fatal. The purpose of this study was to investigate the efficacy of technetium-99m hexamethylpropylene amine oxime (HMPAO) leucocyte scintigraphy in the diagnosis of TOA. Twenty women with high clinical suspicion of TOA underwent 99mTc-HMPAO leucocyte scintigraphy. The labelling of leucocytes with 99mTc-HMPAO was performed according to a standard protocol. Scans were obtained at 1, 3 and 24 h following the injection of the labelled leucocytes. In eight cases the early and/or late scan was positive, in 11 cases it was negative, and in one case of ovarian cyst torsion, confirmed by laparoscopy, it showed slight uptake in the capsule of the cyst (false-positive). The sensitivity of 99mTc-HMPAO leucocyte scintigraphy was 100%, specificity 91.6%, positive predictive value 89%, negative predictive value 100% and overall accuracy 95%. It is concluded that leucocyte scintigraphy is a non-invasive, safe, physiological and accurate procedure for the diagnosis of TOA. The 24-h scan is crucial, since in some cases the abscess was not clearly visualized on the early scan. Leucocyte scintigraphy may reduce the need for CT, diagnostic laparoscopy and unnecessary invasive surgical procedures. PMID:11189939

  10. Comparison of technetium-99m-HMPAO and technetium-99m-ECD cerebral SPECT images in Alzheimer`s disease

    SciTech Connect

    Dyck, C.H. van; Lin, C.H.; Smith, E.O.

    1996-11-01

    SPECT has shown increasing promise as a diagnostic tool in Alzheimer`s disease (AD). Recently, a new SPECT brain perfusion agent, {sup 99m}Tc-ethyl cysteinate dimer ({sup 99m}Tc-ECD) has emerged with purported advantages in image quality over the established tracer, {sup 99m}Tc-hexamethylpropyleneamine oxime ({sup 99m}Tc-HMPAO). This research aimed to compare cerebral images for ({sup 99m}Tc-HMPAO). This research aimed to compare cerebral images for {sup 99}mTc-HMPAO and {sup 99m}Tc-ECD in discriminating patients with AD form control subjects. 51 refs., 5 figs., 3 tabs.

  11. Lassen's equation is a good approximation of permeability-surface model: new α values for 99mTc-HMPAO and 99mTc-ECD

    PubMed Central

    Kameyama, Masashi

    2014-01-01

    Brain perfusion tracers like [99mTc] d,l-hexamethyl-propyeneamine oxime (99mTc-HMPAO) and [99mTc] ethyl-cysteinate dimer (99mTc-ECD) underestimate regional cerebral blood flow (rCBF) at high flow values. To improve linearity between tracer accumulation and rCBF, two different models have been proposed. One is Lassen's correction algorithm for back-diffusion of tracer, and the other is based on the permeability-surface (PS) model for correction of low first-pass extraction. Although both these models have the same goal, they have completely different forms of equation. It was demonstrated that mathematical approximation of the PS model equation leads to Lassen's equation. In this process, the relationship between PS, CBF values and Lassen's parameter was acquired, and how to correct both the back-diffusion and low first-pass extraction was also demonstrated. A computer simulation confirmed that the two models provided similar consequences when the parameter value is chosen according to the relationship found. Lassen's equation can be used to correct not only back-diffusion but also low first-pass extraction. To perform overall correction, the parameter value we have been using for decades may be too weak. I estimated that the parameter value for overall correction of HMPAO would be around 0.5, and that of ECD would be around 0.65. PMID:24736892

  12. Simultaneous administration of 111In-human immunoglobulin and 99mTc-HMPAO labelled leucocytes in inflammatory bowel disease.

    PubMed

    Mairal, L; de Lima, P A; Martin-Comin, J; Baliellas, C; Xiol, X; Roca, M; Ricart, Y; Ramos, M

    1995-07-01

    Technetium-99m hexamethylpropylene amine oxime (HMPAO) labelled leucocytes and indium-111 polyclonal immunoglobulin (IgG) were simultaneously injected into a group of 27 patients routinely referred for the investigation of inflammatory bowel disease (IBD). Ten-minute anterior abdomen and tail on detector views were obtained at 30 min, 4 h and 24 h p.i. of both tracers. The diagnosis of IBD was obtained in all cases by endoscopy with biopsy and/or surgery. Images were blindly evaluated by two experienced observers who only knew of the clinical suspicion of IBD. IBD was confirmed in 20 patients (12 with Crohn's disease and eight with ulcerative colitis). Sensitivity, specificity and accuracy were 100%, 85% and 96% respectively for labelled leucocytes and 70%, 85% and 74% for IgG. Both IgG and leucocyte scans were normal in six out of seven patients in whom a diagnosis of IBD was excluded; the remaining patient, with ischaemic colitis, was falsely positive with both agents. As far as disease extension is concerned, the IgG study localized 27 diseased segments, whereas 49 were seen with the leucocyte study. Eighty-four segments were normal and 25 showed tracer uptake with both agents. Twenty-four were positive only with the leucocyte study and two were positive only with the IgG study. Agreement between the agents was 80.7%. These results confirm that 111In-human polyclonal scintigraphy is less sensitive than 99mTc-HMPAO scintigraphy both for the diagnosis of IBD and in the evaluation of disease extension. Nevertheless, if leucocyte labelling is not available, labelled IgG can be used only for diagnostic purposes. PMID:7498228

  13. [Effects of treatment with OKT3 on brain perfusion in a heart transplant patient with SPET with 99mTc-HMPAO].

    PubMed

    Quirce, R; Carril, J; Vallina, N; Montero, A; Uriarte, I

    1999-10-01

    A heart transplant patient treated with OKT3 developed a severe headache which worsened and was accompanied by a sudden decrease in the patient's consciousness level and aphasia when the treatment course was completed. CT was performed and was normal. SPET imaging with 99mTc-HMPAO of cerebral blood flow done 16 hours later revealed multiple and clear focal defects in the blood flow. Analysis of cerebral spinal fluid revealed aseptic pleocytosis. Five days after the completion of treatment, the symptoms remitted and a new control SPET 3 weeks later was completely normal. A diagnosis of neurotoxicity secondary to OKT3 administration was established. PMID:10562666

  14. Computer-assisted superimposition of magnetic resonance and high-resolution technetium-99m-HMPAO and thallium-201 SPECT images of the brain

    SciTech Connect

    Holman, B.L.; Zimmerman, R.E.; Johnson, K.A.; Carvalho, P.A.; Schwartz, R.B.; Loeffler, J.S.; Alexander, E.; Pelizzari, C.A.; Chen, G.T. )

    1991-08-01

    A method for registering three-dimensional CT, MR, and PET data sets that require no special patient immobilization or other precise positioning measures was adapted to high-resolution SPECT and MRI and was applied in 14 subjects (five normal volunteers, four patients with dementia (Alzheimer's disease), two patients with recurrent glioblastoma, and three patients with focal lesions (stroke, arachnoid cyst and head trauma)). T2-weighted axial magnetic resonance images and transaxial 99mTc-HMPAO and 201Tl images acquired with an annular gamma camera were merged using an objective registration (translation, rotation and rescaling) program. In the normal subjects and patients with dementia and focal lesions, focal areas of high uptake corresponded to gray matter structures. Focal lesions observed on MRI corresponded to perfusion defects on SPECT. In the patients who had undergone surgical resection of glioblastoma followed by interstitial brachytherapy, increased 201Tl corresponding to recurrent tumor could be localized from the superimposed images. The method was evaluated by measuring the residuals in all subjects and translational errors due to superimposition of deep structures in the 12 subjects with normal thalamic anatomy and 99mTc-HMPAO uptake. This method for superimposing magnetic resonance and high-resolution SPECT images of the brain is a useful technique for correlating regional function with brain anatomy.

  15. Regional cerebral blood flow imaging: A quantitative comparison of technetium-99m-HMPAO SPECT with C15O2 PET

    SciTech Connect

    Gemmell, H.G.; Evans, N.T.; Besson, J.A.; Roeda, D.; Davidson, J.; Dodd, M.G.; Sharp, P.F.; Smith, F.W.; Crawford, J.R.; Newton, R.H. )

    1990-10-01

    The aim of this study was to compare technetium-99m-hexamethylpropyleneamineoxime ({sup 99m}Tc-HMPAO) single-photon emission computed tomography (SPECT) with regional cerebral blood flow (rCBF) imaging using positron emission tomography (PET). As investigation of dementia is likely to be one of the main uses of routine rCBF imaging, 18 demented patients were imaged with both techniques. The PET data were compared quantitatively with three versions of the SPECT data. These were, first, data normalized to the SPECT cerebellar uptake, second, data linearly corrected using the PET cerebellar value and, finally, data Lassen corrected for washout from the high flow areas. Both the linearly-corrected (r = 0.81) and the Lassen-corrected (r = 0.79) HMPAO SPECT data showed good correlation with the PET rCBF data. The relationship between the normalized HMPAO SPECT data and the PET data was nonlinear. It is not yet possible to obtain rCBF values in absolute units from HMPAO SPECT without knowledge of the true rCBF in one reference region for each patient.

  16. Fast Monte Carlo based joint iterative reconstruction for simultaneous 99mTc/ 123I SPECT imaging.

    PubMed

    Ouyang, Jinsong; El Fakhri, Georges; Moore, Stephen C

    2007-08-01

    Simultaneous 99mTC/ 123I SPECT allows the assessment of two physiological functions under identical conditions. The separation of these radionuclides is difficult, however, because their energies are close. Most energy-window-based scatter correction methods do not fully model either physical factors or patient-specific activity and attenuation distributions. We have developed a fast Monte Carlo (MC) simulation-based multiple-radionuclide and multiple-energy joint ordered-subset expectation-maximization (JOSEM) iterative reconstruction algorithm, MC-JOSEM. MC-JOSEM simultaneously corrects for scatter and cross talk as well as detector response within the reconstruction algorithm. We evaluated MC-JOSEM for simultaneous brain profusion (99mTc-HMPAO) and neurotransmission (123I-altropane) SPECT. MC simulations of 99mTc and 123I studies were generated separately and then combined to mimic simultaneous 99mTc/ 123I SPECT. All the details of photon transport through the brain, the collimator, and detector, including Compton and coherent scatter, septal penetration, and backscatter from components behind the crystal, were modeled. We reconstructed images from simultaneous dual-radionuclide projections in three ways. First, we reconstructed the photopeak-energy-window projections (with an asymmetric energy window for 1231) using the standard ordered-subsets expectation-maximization algorithm (NSC-OSEM). Second, we used standard OSEM to reconstruct 99mTc photopeak-energy-window projections, while including an estimate of scatter from a Compton-scatter energy window (SC-OSEM). Third, we jointly reconstructed both 99mTc and 123I images using projection data associated with two photo-peak energy windows and an intermediate-energy window using MC-JOSEM. For 15 iterations of reconstruction, the bias and standard deviation of 99mTc activity estimates in several brain structures were calculated for NSC-OSEM, SC-OSEM, and MC-JOSEM, using images reconstructed from primary

  17. Diagnosis of orbital cavernous hemangioma with Tc-99m RBC SPECT.

    PubMed

    Ki, W W; Shin, J W; Won, K S; Ryu, J S; Yang, S O; Lee, H K; Kim, Y J

    1997-08-01

    The authors report two cases of orbital cavernous hemangioma diagnosed by Tc-99m RBC SPECT. Tc-99m RBC SPECT showed a typical scintigraphic pattern commonly seen in hepatic hemangioma in which there is intense focally increased uptake on delayed SPECT images. Tc-99m RBC SPECT in orbital cavernous hemangioma may be as useful a diagnostic modality as in hepatic hemangioma. PMID:9262901

  18. Comparison of technetium-99m pyrophosphate and technetium-99m DTPA aerosols for SPECT ventilation lung imaging

    SciTech Connect

    Isitman, A.T.; Collier, B.D.; Palmer, D.W.; Trembath, L.; Krasnow, A.Z.; Rao, S.A.; Hellman, R.S.; Hoffmann, R.G.; Peck, D.C.; Dellis, C.J.

    1988-11-01

    Although (/sup 99m/Tc) diethylenetriaminepentaacetic acid (DTPA) is currently the most widely used radioaerosol, rapid alveolar clearance limits its usefulness for single photon emission computed tomography (SPECT) ventilation lung imaging. Previous research has shown that (/sup 99m/Tc)phosphate compounds have high alveolar deposition and slow clearance and thus provide suitable aerosols for pulmonary ventilation studies. We have compared the pulmonary retention and blood levels of (/sup 99m/Tc)pyrophosphate (PYP) and (99mTc)DTPA in eight normal nonsmoking male volunteers. These two radioaerosols have comparable pulmonary deposition. Technetium-99m PYP, however, has a much slower pulmonary clearance which allows sufficient time (20 or more minutes) for SPECT data acquisition using a single-headed rotating gamma camera. While the radiation absorbed dose to the lungs for (/sup 99m/Tc)PYP (0.31 rad/mCi) is greater than for (/sup 99m/Tc)DTPA (0.11 rad/mCi), it is at a clinically acceptable and safe level.

  19. Fast Monte Carlo based joint iterative reconstruction for simultaneous {sup 99m}Tc/{sup 123}I SPECT imaging

    SciTech Connect

    Ouyang Jinsong; El Fakhri, Georges; Moore, Stephen C.

    2007-08-15

    Simultaneous {sup 99m}Tc/{sup 123}I SPECT allows the assessment of two physiological functions under identical conditions. The separation of these radionuclides is difficult, however, because their energies are close. Most energy-window-based scatter correction methods do not fully model either physical factors or patient-specific activity and attenuation distributions. We have developed a fast Monte Carlo (MC) simulation-based multiple-radionuclide and multiple-energy joint ordered-subset expectation-maximization (JOSEM) iterative reconstruction algorithm, MC-JOSEM. MC-JOSEM simultaneously corrects for scatter and cross talk as well as detector response within the reconstruction algorithm. We evaluated MC-JOSEM for simultaneous brain profusion ({sup 99m}Tc-HMPAO) and neurotransmission ({sup 123}I-altropane) SPECT. MC simulations of {sup 99m}Tc and {sup 123}I studies were generated separately and then combined to mimic simultaneous {sup 99m}Tc/{sup 123}I SPECT. All the details of photon transport through the brain, the collimator, and detector, including Compton and coherent scatter, septal penetration, and backscatter from components behind the crystal, were modeled. We reconstructed images from simultaneous dual-radionuclide projections in three ways. First, we reconstructed the photopeak-energy-window projections (with an asymmetric energy window for {sup 123}I) using the standard ordered-subsets expectation-maximization algorithm (NSC-OSEM). Second, we used standard OSEM to reconstruct {sup 99m}Tc photopeak-energy-window projections, while including an estimate of scatter from a Compton-scatter energy window (SC-OSEM). Third, we jointly reconstructed both {sup 99m}Tc and {sup 123}I images using projection data associated with two photopeak energy windows and an intermediate-energy window using MC-JOSEM. For 15 iterations of reconstruction, the bias and standard deviation of {sup 99m}Tc activity estimates in several brain structures were calculated for NSC

  20. 99mTc-MDP SPECT/CT for assessment of condylar hyperplasia.

    PubMed

    Derlin, Thorsten; Busch, Jasmin D; Habermann, Christian R

    2013-01-01

    We report a case of condylar hyperplasia diagnosed with 99mTc-MDP SPECT/CT. A 21-year-old woman with facial asymmetry was referred for assessment of condylar growth activity. SPECT/CT confirmed condylar hyperactivity, and simultaneous low-dose CT contributed to the diagnosis of hemimandibular hyperplasia. SPECT/CT may become a valuable tool for the diagnosis and comprehensive assessment of condylar hyperplasia, providing both functional and morphological information. PMID:23242067

  1. Is Brown Adipose Tissue Visualization Reliable on 99mTc-Methoxyisobutylisonitrile Diagnostic SPECT Scintigraphy?

    PubMed Central

    Haghighatafshar, Mahdi; Farhoudi, Farinaz

    2016-01-01

    Abstract The 99mTc-MIBI has been used with great value as a diagnostic technique in patients with primary hyperparathyroidism. False-positive scans may occur due to misinterpretation of the physiologic distribution of the 99mTc-MIBI. Reviewing consecutive SPECT scans, we evaluated this possibility and assessed how frequently brown adipose tissue (BAT) is seen on 99mTc-MIBI scintigraphy. Here, we retrospectively reviewed scans of consecutive patients who were evaluated for parathyroid adenomas from March 2015 to June 2015, using dual-phase (early and delayed) planar imaging and SPECT. We identified 60 patients (48 female and 12 male; mean age, 52.25 ± 15.20 years; range, 22–86 years). We detected the presence of 99mTc-MIBI uptake in BAT in 20 of 60 patients (33.33%) in the neck. Although the patients with 99mTc-MIBI uptake in BAT were younger (mean age, 48.85 ± 15.27 years, range, 26–73 years) than the patients with no 99mTc-MIBI uptake (mean age, 53.95 ± 15.07 years, range, 22–86 years), this difference was not statistically significant (P = 0.224). The percentage of female patients with BAT detection was higher (17/48 patients; 37.5%) than that of the male population (3/12 patients; 25%), this difference was not also statistically significant (P = 0.85). In patient population referred to 99mTc MIBI scintigraphy of the parathyroid glands, uptake of 99mTc-MIBI in BAT should not be misinterpreted with 99mTc-MIBI-avid-tumors. Fused SPECT/CT images (not SPECT-only) are necessary to distinguish BAT from bone, muscle, thyroid, myocardium, parathyroids, and other structures in the neck and chest. PMID:26765463

  2. Is Brown Adipose Tissue Visualization Reliable on 99mTc-Methoxyisobutylisonitrile Diagnostic SPECT Scintigraphy?

    PubMed

    Haghighatafshar, Mahdi; Farhoudi, Farinaz

    2016-01-01

    The 99mTc-MIBI has been used with great value as a diagnostic technique in patients with primary hyperparathyroidism. False-positive scans may occur due to misinterpretation of the physiologic distribution of the 99mTc-MIBI. Reviewing consecutive SPECT scans, we evaluated this possibility and assessed how frequently brown adipose tissue (BAT) is seen on 99mTc-MIBI scintigraphy. Here, we retrospectively reviewed scans of consecutive patients who were evaluated for parathyroid adenomas from March 2015 to June 2015, using dual-phase (early and delayed) planar imaging and SPECT. We identified 60 patients (48 female and 12 male; mean age, 52.25 ± 15.20 years; range, 22-86 years).We detected the presence of 99mTc-MIBI uptake in BAT in 20 of 60 patients (33.33%) in the neck. Although the patients with T99mc-MIBI uptake in BAT were younger (mean age, 48.85 ± 15.27 years, range, 26-73 years) than the patients with no 99mTc-MIBI uptake (mean age, 53.95 ± 15.07 years, range, 22-86 years), this difference was not statistically significant (P = 0.224). The percentage of female patients with BAT detection was higher (17/48 patients; 37.5%) than that of the male population (3/12 patients; 25%), this difference was not also statistically significant (P = 0.85).In patient population referred to 99mTc MIBI scintigraphy of the parathyroid glands, uptake of 99mTc-MIBI in BAT should not be misinterpreted with 99mTc-MIBI-avid-tumors. Fused SPECT/CT images (not SPECT-only) are necessary to distinguish BAT from bone, muscle, thyroid, myocardium, parathyroids, and other structures in the neck and chest. PMID:26765463

  3. Ectopic Intrathymic Parathyroid adenoma demonstrated on Tc-99m Sestamibi SPECT-CT.

    PubMed

    Usmani, S; Oteifa, M; Abu Huda, F; Javaid, A; Amanguno, H G; Al Kandari, F

    2016-05-01

    Intrathymic parathyroid adenoma is a rare cause of primary hyperparathyroidism. In this case, Tc-99m Sestamibi SPECT-CT successfully localized abnormal tracer uptake in the mediastinum with corresponding low density lesion on CT images suggestive of mediastinal parathyroid adenoma which late on confirmed on histopathology. After the median sternotomy a large intrathymic parathyroid adenoma was identified and excised. With the help of gamma probe the surgeons detect the lesion early and with more confidence as well as reducing the total operation time. Tc-99m Sestamibi SPECT-CT scintigraphy and gamma probe localization is recommended for preoperative and intra operative localization of ectopic parathyroid adenomas. PMID:27250890

  4. SPECT measurements with /sup 99m/Tc-HM-PAO in focal epilepsy

    SciTech Connect

    Ryding, E.; Rosen, I.; Elmqvist, D.; Ingvar, D.H.

    1988-12-01

    The ability of SPECT measurements with (/sup 99m/Tc)-HM-PAO (Ceretec) to find the location of the epileptic focus was studied in patients under consideration for neurosurgical treatment for therapy-resistant focal epilepsy. The location of low (/sup 99m/Tc)-HM-PAO uptake regions found at interictal measurements, and of high (/sup 99m/Tc)-HM-PAO uptake regions found at ictal measurements, was compared to the findings of extensive ictal and interictal EEG examinations, and to the results of CT and MRT. While EEG revealed focal epileptic activity in all of the 14 patients, SPECT showed regional abnormalities in 13 (93%). CT and MRT showed abnormal findings in 30%.

  5. 99mTc-Macroaggregated Albumin SPECT/CT Perfusion Imaging of Omental Extrahepatic Vascularization.

    PubMed

    Nguyen, Ba D; Yang, Ming; Roarke, Michael C

    2016-01-01

    The authors present a case of omental perfusion by an extrahepatic branch of the right hepatic artery depicted during pre-embolization planning with 99mTc-macroaggregated albumin SPECT/CT imaging. This omental scintigraphic finding corresponds to an extrahepatic branch of the right hepatic artery demonstrated by selective angiography and related CT angiography. The authors would like to add the omentum to the previously reported sites of extrahepatic vascularization encountered during the hepatic pre-embolization imaging. PMID:26650883

  6. Quantitative simultaneous 111In/99mTc SPECT-CT of osteomyelitis

    PubMed Central

    Cervo, Morgan; Gerbaudo, Victor H.; Park, Mi-Ae; Moore, Stephen C.

    2013-01-01

    Purpose: A well-established approach for diagnostic imaging of osteomyelitis (OM), a bone infection, is simultaneous SPECT-CT of 99mTc sulfur colloid (SC) and 111In white blood cells (WBC). This method provides essentially perfect spatial registration of the tracers within anatomic sites of interest. Currently, diagnosis is based purely on a visual assessment—where relative discordance between 99mTc and 111In uptake in bone, i.e., high 111In and low 99mTc, suggests OM. To achieve more quantitative images, noise, scatter, and crosstalk between radionuclides must be addressed through reconstruction. Here the authors compare their Monte Carlo-based joint OSEM (MC-JOSEM) algorithm, which reconstructs both radionuclides simultaneously, to a more conventional triple-energy window-based reconstruction (TEW-OSEM), and to iterative reconstruction with no compensation for scatter (NC-OSEM). Methods: The authors created numerical phantoms of the foot and torso. Multiple bone-infection sites were modeled using high-count Monte Carlo simulation. Counts per voxel were then scaled to values appropriate for 111In WBC and 99mTc SC imaging. Ten independent noisy projection image sets were generated by drawing random Poisson deviates from these very low-noise images. Data were reconstructed using the two iterative scatter-compensation methods, TEW-OSEM and MC-JOSEM, as well as the uncorrected method (NC-OSEM). Mean counts in volumes of interest (VOIs) were used to evaluate the bias and precision of each method. Data were also acquired using a phantom, approximately the size of an adult ankle, consisting of regions representing infected and normal bone marrow, within a bone-like attenuator and surrounding soft tissue; each compartment contained a mixture of 111In and 99mTc. Low-noise data were acquired during multiple short scans over 29 h on a Siemens Symbia T6 SPECT-CT with medium-energy collimators. Pure 99mTc and 111In projection datasets were derived by fitting the acquired

  7. Extracranial metastatic glioblastoma: Appearance on thallium-201-chloride/technetium-99m-HMPAO SPECT images

    SciTech Connect

    Carvalho, P.A.; Schwartz, R.B.; Alexander, E. III; Loeffler, J.S.; Zimmerman, R.E.; Nagel, J.S.; Holman, B.L. )

    1991-02-01

    Sequential thallium-201-chloride and technetium-99m-hexamethylpropyleneamine oxime single-photon emission computed tomography (SPECT) images were obtained in a patient with extracranial metastatic glioblastoma multiforme. Thallium-201 uptake was high (three times the scalp background) in all pathologically confirmed extracranial metastases and moderate (1.6 times scalp background) intracranially, where most biopsy specimens showed gliosis with scattered atypical astrocytes. Technetium-99m-HMPAO uptake was decreased intracranially in the right frontal and parietal lobes which had been irradiated. It was also decreased in one well-encapsulated scalp lesion and high in another scalp mass with less defined borders. Possible mechanisms of tumor uptake of these agents are reviewed.

  8. Spatially resolved assessment of hepatic function using 99mTc-IDA SPECT

    SciTech Connect

    Wang, Hesheng; Cao, Yue

    2013-09-15

    Purpose: 99mTc-iminodiacetic acid (IDA) hepatobiliary imaging is usually quantified for hepatic function on the entire liver or regions of interest (ROIs) in the liver. The authors presented a method to estimate the hepatic extraction fraction (HEF) voxel-by-voxel from single-photon emission computed tomography (SPECT)/CT with a 99mTc-labeled IDA agent of mebrofenin and evaluated the spatially resolved HEF measurements with an independent physiological measurement.Methods: Fourteen patients with intrahepatic cancers were treated with radiation therapy (RT) and imaged by 99mTc-mebrofenin SPECT before and 1 month after RT. The dynamic SPECT volumes were with a resolution of 3.9 × 3.9 × 2.5 mm{sup 3}. Throughout the whole liver with approximate 50 000 voxels, voxelwise HEF quantifications were estimated and compared between using arterial input function (AIF) from the heart and using vascular input function (VIF) from the spleen. The correlation between mean of the HEFs over the nontumor liver tissue and the overall liver function measured by Indocyanine green clearance half-time (T1/2) was assessed. Variation of the voxelwise estimation was evaluated in ROIs drawn in relatively homogeneous regions of the livers. The authors also examined effects of the time range parameter on the voxelwise HEF quantification.Results: Mean of the HEFs over the liver estimated using AIF significantly correlated with the physiological measurement T1/2 (r= 0.52, p= 0.0004), and the correlation was greatly improved by using VIF (r= 0.79, p < 0.0001). The parameter of time range for the retention phase did not lead to a significant difference in the means of the HEFs in the ROIs. Using VIF and a retention phase time range of 7–30 min, the relative variation of the voxelwise HEF in the ROIs was 10%± 6% of respective mean HEF.Conclusions: The voxelwise HEF derived from 99mTc-IDA SPECT by the deconvolution analysis is feasible to assess the spatial distribution of hepatic function in the

  9. Benign incidental findings of osteopoikilosis on Tc-99m MDP bone SPECT/CT

    PubMed Central

    Tsai, Szu-Ying; Wang, Shan-Ying; Shiau, Yu-Chien; Wu, Yen-Wen

    2016-01-01

    Abstract Osteopoikilosis is a benign but rare condition characterized by bone islands throughout the osseous tissue, which could be easily confused with bone metastasis. We present a case of a 37-year-old man presented to orthopedic outpatient clinic with right hip pain for 2 weeks. There were multiple, small punctate lesions scattered throughout the skeleton on radiograph. Subsequent Tc-99m methylene diphosphonate (MDP) bone scan with pelvic single-photon emission computed tomography (SPECT)/computed tomography (CT) showed multiple enostoses without abnormal focal MDP uptake. Therefore, clinical diagnosis was compatible with osteopoikilosis while bone metastasis was unlikely. The symptoms then improved by conservative treatments. Osteopoikilosis is usually an incidental finding on radiograph or CT, and a normal MDP confirmed the diagnosis by excluding bone metastasis. It is important for clinicians to recognize the specific image features to prevent further unnecessary interventions. In addition, bone SPECT/CT could also make the diagnosis in one step. PMID:27281099

  10. Systematic evaluation of 99mTc-tetrofosmin versus 99mTc-sestamibi to study murine myocardial perfusion in small animal SPECT/CT

    PubMed Central

    2012-01-01

    Background The “back-translation” of clinically available protocols to measure myocardial perfusion to preclinical imaging in mouse models of human disease is attractive for basic biomedical research. With respect to single-photon emission computed tomography (SPECT) approaches, clinical myocardial perfusion imaging protocols are established with different 99mTc-labeled perfusion tracers; however, studies evaluating and optimizing protocols for these tracers in high-resolution pinhole SPECT in mice are lacking. This study aims at evaluating two clinically available 99mTc-labeled myocardial perfusion tracers (99mTc-sestamibi vs. 99mTc-Tetrofosmin) in mice using four different imaging protocols. Methods Adult C57BL/6 male mice were injected with 99mTc-sestamibi (MIBI) or 99mTc-Tetrofosmin (TETRO) (4 MBq/g body weight) either intravenously through the tail vein (n = 5) or retroorbitally (n = 5) or intraperitoneally (i.p.) under anesthesia (n = 3) or i.p. in an awake state (n = 3) at rest. Immediately after injection, a multi-frame single-photon emission computed tomography/computed tomography (SPECT/CT) acquisition was initiated with six subsequent time frames of 10 min each. Reconstructed images of the different protocols were assessed and compared by visual analysis by experts and by time-activity-curves generated from regions-of-interest for various organs (normalized uptake values). Results Visually assessing overall image quality, the best image quality was found for MIBI for both intravenous injection protocols, whereas TETRO only had comparable image quality after retroorbital injections. These results were confirmed by quantitative analysis where left ventricular (LV) uptake of MIBI after tail vein injections was found significantly higher for all time points accompanied with a significantly slower washout of 16% for MIBI vs. 33% for TETRO (p = 0.009) from 10 to 60 min post injection (PI). Interestingly, LV washout from 10 to 60 min PI

  11. CT/99mTc-GSA SPECT fusion images demonstrate functional differences between the liver lobes

    PubMed Central

    Sumiyoshi, Tatsuaki; Shima, Yasuo; Tokorodani, Ryoutarou; Okabayashi, Takehiro; Kozuki, Akihito; Hata, Yasuhiro; Noda, Yoshihiro; Murata, Yoriko; Nakamura, Toshio; Uka, Kiminori

    2013-01-01

    AIM: To evaluate the functional differences between the 2 liver lobes in non-cirrhotic patients by using computed tomography/99mTc-galactosyl human serum albumin (CT/99mTc-GSA) single-photon emission computed tomography (SPECT) fusion images. METHODS: Between December 2008 and March 2012, 264 non-cirrhotic patients underwent preoperative liver function assessment using CT/99mTc-GSA SPECT fusion images. Of these, 30 patients, in whom the influence of a tumor on the liver parenchyma was estimated to be negligible, were selected. Specifically, the selected patients were required to meet either of the following criteria: (1) the presence of an extrahepatic tumor; or (2) presence of a single small intrahepatic tumor. These 30 patients were retrospectively analyzed to calculate the percentage volume (%Volume) and the percentage function (%Function) of each lobe. The ratio between the %Function and %Volume (function-to-volume ratio) of each lobe was also calculated, and the ratios were compared between the 2 lobes. Furthermore, the correlations between the function-to-volume ratio and each of 2 liver parameters [lobe volume and diameter ratio of the left portal vein to the right portal vein (LPV-to-RPV diameter ratio)] were investigated. RESULTS: The median values of %Volume and %Function were 62.6% and 67.1% in the right lobe, with %Function being significantly higher than %Volume (P < 0.01). The median values of %Volume and %Function were 31.0% and 28.7% in the left lobe, with %Function being significantly lower than %Volume (P < 0.01). The function-to-volume ratios of the right lobe (1.04-1.14) were significantly higher than those of the left lobe (0.74-0.99) (P < 0.01). The function-to-volume ratio showed no significant correlation between the lobe volume in either lobe. In contrast, the function-to-volume ratio showed significant correlations with the LPV-to-RPV diameter ratio in both lobes (right lobe: negative correlation, rs = -0.37, P = 0.048; left lobe: positive

  12. Physical phantom evaluation of simultaneous 99mTc/ 123I SPECT imaging

    NASA Astrophysics Data System (ADS)

    Yang, Bang-Hung; Wang, Shyh-Jen; Lee, Jhih-Shian; Jan, Meei-Ling; Chang, Chia-Jung; Chen, Jyh-Cheng

    2011-10-01

    .03 and that of 123I was 1.07 from the W_eICA method. Besides, the recovery rate of 99mTc was 0.84 and that of 123I was 1.05 from the AEW approach. According to our results, the W_eICA method not only decreased the number of energy windows but also separated dual-isotope photopeaks successfully. The results have demonstrated that the W_eICA method improved the quantitative accuracy and might be an effective tool for simultaneous dual-isotope SPECT imaging.

  13. Analysis of the Reconstructibility and Noise Properties of Scattered Photons in Tc-99m SPECT

    PubMed Central

    Kadrmas, Dan J; Frey, Eric C; Tsui, Benjamin M W

    2009-01-01

    Since scattered photons carry degraded spatial information, scatter is typically considered a source of contamination in SPECT. However, with the advent of scatter modeling methods and reconstruction-based scatter compensation (RBSC), it may be possible to utilize scattered data in a productive manner. In this work we analyze the reconstructibility of scattered photon projection data and investigate the potential for using scattered photons to reduce the noise levels of SPECT images. We have simulated projection data for an elliptical phantom containing three cold rods in a uniform background of Tc-99m activity. A variety of photopeak and scatter energy windows were formed, as well as corresponding RBSC transfer matrices. Each statistically weighted matrix was decomposed using SVD and analyzed in terms of reconstructibility and noise properties. Results indicate that scattered photons contain sufficient information to reconstruct the source activity, but the scatter-only matrices are very poorly conditioned. We have also evaluated several methods of utilizing scattered events via RBSC, and compared them with other, idealized methods of handling scatter. It was found that scattered photons can be used productively when photopeak and non-photopeak data are separated through the use of multiple energy windows. The RBSC methods outperformed ideal scatter subtraction, but fell short of methods which assume perfect discrimination between scattered and primary events. The knowledge gained by this study may help guide future research and lead to better approaches to handling scatter in SPECT. PMID:9434303

  14. Differential diagnosis of regional cerebral hyperfixation of TC-99m HMPAO on SPECT imaging

    SciTech Connect

    Shirazi, P.; Konopka, L.; Crayton, J.W.

    1994-05-01

    Accurate diagnostic evaluation of patients with neurologic and neuropsychiatric disease is important because early treatment may halt disease progression and prevent impairment or disability. Cerebral hyperfixation of HMPAO has been ascribed to luxury perfusion following ischemic infarction. The present study sought to identify other conditions that also display radiotracer hyperfixation in order to develop a differential diagnosis of this finding on SPECT imaging. Two hundred fifty (n=250) successive cerebral SPECT images were reviewed for evidence of HMPAO hyperfixation. Hyperfixation was defined as enhanced focal perfusion surrounded by a zone of diminished or normal cerebral perfusion. All patients were scanned after intravenous injection of 25 mCi Tc-99m HMPAO. Volume-rendered and oblique images were obtained with a Trionix triple-head SPECT system using ultra high resolution fan beam collimators. Thirteen (13/250; 5%) of the patients exhibited regions of HMPAO hyperfixation. CT or MRI abnormalities were detected in 6/13 cases. Clinical diagnoses in these patients included intractable psychosis, post-traumatic stress disorder, alcohol and narcotic dependence, major depression, acute closed-head trauma, hypothyroidism, as well as subacute ischemic infarction. A wide variety of conditions may be associated with cerebral hyperfixation of HMPAO. These conditions include neurologic and psychiatric diagnoses, and extend the consideration of hyperfixation beyond ischemic infarction. Consequently, a differential diagnosis of HMPAO hyperfixation may be broader than originally considered, and this may suggest a fundamental role for local cerebral hyperperfusion. Elucidation of the fundamental mechanism(s) for cerebral hyperperfusion requires further investigation.

  15. Quantitative simultaneous 99mTc∕123I cardiac SPECT using MC-JOSEM

    PubMed Central

    Ouyang, Jinsong; Zhu, Xuping; Trott, Cathryn M.; El Fakhri, Georges

    2009-01-01

    Simultaneous rest 99mTc-Sestamibi∕123I-BMIPP cardiac SPECT imaging has the potential to replace current clinical 99mTc-Sestamibi rest∕stress imaging and therefore has great potential in the case of patients with chest pain presenting to the emergency department. Separation of images of these two radionuclides is difficult, however, because their emission energies are close. The authors previously developed a fast Monte Carlo (MC)-based joint ordered-subset expectation maximization (JOSEM) iterative reconstruction algorithm (MC-JOSEM), which simultaneously compensates for scatter and cross talk as well as detector response within the reconstruction algorithm. In this work, the authors evaluated the performance of MC-JOSEM in a realistic population of 99mTc∕123I studies using cardiac phantom data on a Siemens e.cam system using a standard cardiac protocol. The authors also compared the performance of MC-JOSEM for estimation tasks to that of two other methods: standard OSEM using photopeak energy windows without scatter correction (NSC-OSEM) and standard OSEM using a Compton-scatter energy window for scatter correction (SC-OSEM). For each radionuclide the authors separately acquired high-count projections of radioactivity in the myocardium wall, liver, and soft tissue background compartments of a water-filled torso phantom, and they generated synthetic projections of various dual-radionuclide activity distributions. Images of different combinations of myocardium wall∕background activity concentration ratios for each radionuclide were reconstructed by NSC-OSEM, SC-OSEM, and MC-JOSEM. For activity estimation in the myocardium wall, MC-JOSEM always produced the best relative bias and relative standard deviation compared with NSC-OSEM and SC-OSEM for all the activity combinations. On average, the relative biases after 100 iterations were 8.1% for 99mTc and 3.7% for 123I with MC-JOSEM, 39.4% for 99mTc and 23.7% for 123I with NSC-OSEM, and 20.9% for 99mTc with SC

  16. 99mTc-red blood cells SPECT and planar scintigraphy in the diagnosis of hepatic hemangiomas.

    PubMed

    Artiko, M V; Sobić-Saranović, P D; Perisić-Savić, S M; Stojković, V M; Radoman, B I; Knezević, S J; Petrović, S N; Obradović, B V; Milović, V

    2008-01-01

    The aim of the study is the assessment of the value of SPECT (single photon emission computerized tomography) using 99mTc-labeled red blood cells in the detection of liver hemangioma, in comparison to planar imaging. With planar red blood cell scintigraphy, sensitivity of the method was 76%, specificity 98%, positive predictive value 98% and negative predictive value 79%. With SPECT, sensitivity of the method was 95%, specificity 98%, positive predictive value 98% and negative predictive value 94%. The smallest lesion detected by planar red blood cell scintigraphy was 1.2 cm, and with SPECT red blood cell scintigraphy 0.8 cm. The use of 99mTc-labeled red blood cells SPECT improved the sensitivity much more in smaller lesions (0.8 to 2 cm), than in bigger ones (2-5 cm). SPECT with radiolabeled red blood cells significantlyy improves the results of scintigraphic findings, especially in the small lesions. PMID:19245136

  17. Parathyroid scintigraphy in patients with primary hyperparathyroidism: 99mTc sestamibi SPECT and SPECT/CT.

    PubMed

    Eslamy, Hedieh K; Ziessman, Harvey A

    2008-01-01

    The clinical diagnosis of primary hyperparathyroidism is based largely on serum laboratory test results, as patients often are asymptomatic. Surgery, often with bilateral exploration of the neck, has been considered the definitive treatment for symptomatic disease. However, given that approximately 90% of cases are due to a single parathyroid adenoma, a better treatment may be the selective surgical excision of the hyperfunctioning parathyroid gland after its preoperative identification and localization at radiologic imaging. Scintigraphy and ultrasonography are the imaging modalities most often used for preoperative localization. Various scintigraphic protocols may be used in the clinical setting: Single-phase dual-isotope subtraction imaging, dual-phase single-isotope imaging, or a combination of the two may be used to obtain planar or tomographic views. Single photon emission computed tomography (SPECT) with the use of technetium-99m ((99m)Tc) sestamibi as the radiotracer, especially when combined with x-ray-based computed tomography (CT), is particularly helpful for preoperative localization: The three-dimensional functional information from SPECT is fused with the anatomic information obtained from CT. In addition, knowledge of the anatomy and embryologic development of the parathyroid glands and the pathophysiology of primary hyperparathyroidism aid in the identification and localization of hyperfunctioning glands. PMID:18794320

  18. Comparison of 18F PET and 99mTc SPECT imaging in phantoms and in tumored mice.

    PubMed

    Cheng, Dengfeng; Wang, Yi; Liu, Xinrong; Pretorius, P Hendrik; Liang, Minmin; Rusckowski, Mary; Hnatowich, Donald J

    2010-08-18

    Our objective was to compare the performance of a micro-single photon emission computed tomography (micro-SPECT) with that of a micro-positron emission tomography (microPET) in a Her2+ tumored mice using an anti-Her2 nanoparticle radiolabeled with (99m)Tc and (18)F. Camera performance was first compared using phantoms; then a tumored mouse administered the (99m)Tc-nanoparticle was imaged on a Bioscan NanoSPECT/CT, while another tumored mouse received the identical nanoparticle, labeled now with (18)F, and was imaged on a Philips Mosaic HP PET camera. The nanoparticle was radiolabeled with (99m)Tc via MAG(3) chelation and with (18)F via SFB as an intermediate. Phantom imaging showed that the resolution of the SPECT camera was clearly superior, but even with 4 heads and multipinhole collimators, detection sensitivity was 15-fold lower. Radiolabeling of the nanoparticle by chelation with (99m)Tc was considerably easier and safer than manual covalent attachment of (18)F. Both cameras provided accurate quantitation of radioactivity over a broad range. In conclusion, when deciding between (99m)Tc vs (18)F, an advantage rests with the chelation of (99m)Tc over covalent attachment of (18)F, achieved manually or otherwise, but with these small animal cameras, this choice also results in trading lower sensitivity for higher resolution. PMID:20681508

  19. Regional brain perfusion in 10 normal dogs measured using Technetium-99m ethyl cysteinate dimer spect.

    PubMed

    Peremans, K; De Bondt, P; Audenaert, K; Van Laere, K; Gielen, I; Koole, M; Versijpt, J; Van Bree, H; Verschooten, F; Dierckx, R

    2001-01-01

    Single photon emission computed tomography (SPECT) of the brain using perfusion tracers allows estimation of regional brain perfusion. This allows in vivo examination of brain function in the setting of neuropsychologic and pathophysiologic changes. However functional imaging data on brain perfusion in dogs are limited. Hence, the aim of this study was to determine the scintigraphic regional perfusion pattern of the normal canine brain. Ten healthy shepherd type dogs were injected with 925 MBq Technetium-99m ethyl cysteinate (ECD) 20 minutes before the examination. Acquisition was performed using a triple head gamma camera equipped with fanbeam collimators. Uniform attenuation correction and triple energy window correction were applied. Computed tomographic images were obtained from the same dogs, reoriented along the orbito-meatal axis and SPECT perfusion data were coregistered to the CT-volume data. Based on morphological and suggested brain divisions, regions-of-interest (ROIs) were defined for the bilateral frontocerebral, temporocerebral, parietocerebral, occipitocerebral, cerebellar, thalamic, and striatal area. Regional count density was normalized on total counts. All dogs had the highest uptake in the thalamic/striatal area compared to a rather homogeneous cerebral uptake. No significant left/right count differences were found, but a rostro-caudal gradient (+12-13%) was present. In this group, age and gender did not influence the perfusion pattern. PMID:11768526

  20. Free craniotomy versus osteoplastic craniotomy, assessment of flap viability using 99mTC MDP SPECT.

    PubMed

    Shelef, Ilan; Golan, Haim; Merkin, Vladimir; Melamed, Israel; Benifla, Mony

    2016-09-01

    There are currently two accepted neurosurgical methods to perform a bony flap. In an osteoplastic flap, the flap is attached to surrounding muscle. In a free flap, the flap is not attached to adjacent tissues. The former is less common due to its complexity and the extensive time required for the surgery; yet the rate of infection is significantly lower, a clear explanation for which is unknown. The objective of this study was to test the hypothesis that the osteoplastic flap acts as a live implant that resumes its blood flow and metabolic activity; contrasting with the free flap, which does not have sufficient blood flow, and therefore acts as a foreign body. Seven patients who underwent craniotomy with osteoplastic flaps and five with free flaps had planar bone and single photon emission computed tomography (SPECT) scans of the skull at 3-7days postoperative, after injection of the radioisotope, 99m-technetium-methylene diphosphonate (99m-Tc-MDP). We compared radioactive uptake as a measure of metabolic activity between osteoplastic and free flaps. Mean normalized radioactive uptakes in the centers of the flaps, calculated as the ratios of uptakes in the flap centers to uptakes in normal contralateral bone, were [mean: 1.7 (SD: 0.8)] and [0.6 (0.1)] for the osteoplastic and free flap groups respectively and were [2.4 (0.8)] and [1.3 (0.4)] in the borders of the flaps. Our analyses suggest that in craniotomy, the use of an osteoplastic flap, in contrast to free flap, retains bone viability. PMID:27068014

  1. A technique using {sup 99m}Tc-mebrofenin SPECT for radiotherapy treatment planning for liver cancers or metastases

    SciTech Connect

    Shen, Sui; Jacob, Rojymon; Bender, Luvenia W.; Duan, Jun; Spencer, Sharon A.

    2014-04-01

    Radiotherapy or stereotactic body radiosurgery (SBRT) requires a sufficient functional liver volume to tolerate the treatment. The current study extended the work of de Graaf et al. (2010) [3] on the use of {sup 99m}Tc-mebrofenin imaging for presurgery planning to radiotherapy planning for liver cancer or metastases. Patient was immobilized and imaged in an identical position on a single-photon emission computed tomography/computed tomography (SPECT-CT) system and a radiotherapy simulation CT system. {sup 99m}Tc-mebrofenin SPECT was registered to the planning CT through image registration of noncontrast CT from SPECT-CT system to the radiotherapy planning CT. The voxels with higher uptake of {sup 99m}Tc-mebrofenin were transferred to the planning CT as an avoidance structure in optimizing a 2-arc RapidArc plan for SBRT delivery. Excellent dose coverage to the target and sparing of the healthy remnant liver volume was achieved. This report illustrated a procedure for the use of {sup 99m}Tc-mebrofenin SPECT for optimizing radiotherapy for liver cancers and metastases.

  2. Importance of Heparin Provocation and SPECT/CT in Detecting Obscure Gastrointestinal Bleeding on 99mTc-RBC Scintigraphy

    PubMed Central

    Haghighatafshar, Mahdi; Gheisari, Farshid; Ghaedian, Tahereh

    2015-01-01

    Abstract We presented a pediatric case with a history of intermittent melena for 3 years because of angiodyplasia of small intestine. The results of frequent upper gastrointestinal endoscopies and colonoscopies as well as both 99mTc-red blood cell (RBC) and Meckel's scintigraphies for several times were negative in detection of bleeding site. However, 99mTc-RBC scintigraphy with single-photon emission computed tomography (SPECT)/computed tomography (CT) after heparin augmentation detected a site of bleeding in the distal ileum which later was confirmed during surgery with final diagnosis of angiodysplasia. It could be stated that heparin provocation of bleeding before 99mTc-RBC scintigraphy accompanied by fused SPECT/CT images should be kept in mind for management of intestinal bleeding especially in difficult cases. PMID:26313771

  3. Personalized predictive lung dosimetry by technetium-99m macroaggregated albumin SPECT/CT for yttrium-90 radioembolization

    PubMed Central

    2014-01-01

    Background For yttrium-90 (90Y) radioembolization, the common practice of assuming a standard 1,000-g lung mass for predictive dosimetry is fundamentally incongruent with the modern philosophy of personalized medicine. We recently developed a technique of personalized predictive lung dosimetry using technetium-99m (99mTc) macroaggregated albumin (MAA) single photon emission computed tomography with integrated CT (SPECT/CT) of the lung as part of our routine dosimetric protocol for 90Y radioembolization. Its rationales are the technical superiority of SPECT/CT over planar scintigraphy, ease and convenience of lung auto-segmentation CT densitovolumetry, and dosimetric advantage of patient-specific lung parenchyma masses. Methods This is a retrospective study of our pulmonary clinical outcomes and comparison of lung dosimetric accuracy and precision by 99mTc MAA SPECT/CT versus conventional planar methodology. 90Y resin microspheres (SIR-Spheres) were used for radioembolization. Diagnostic CT densitovolumetry was used as a reference for lung parenchyma mass. Pulmonary outcomes were based on follow-up diagnostic CT chest or X-ray. Results Thirty patients were analyzed. The mean lung parenchyma mass of our Southeast Asian cohort was 822 ± 103 g standard deviation (95% confidence interval 785 to 859 g). Patient-specific lung parenchyma mass estimation by CT densitovolumetry on 99mTc MAA SPECT/CT is accurate (bias −21.7 g) and moderately precise (95% limits of agreement −194.6 to +151.2 g). Lung mean radiation absorbed doses calculated by 99mTc MAA SPECT/CT and planar methodology are both accurate (bias <0.5 Gy), but 99mTc MAA SPECT/CT offers better precision over planar methodology (95% limits of agreement −1.76 to +2.40 Gy versus −3.48 to +3.31 Gy, respectively). None developed radiomicrosphere pneumonitis when treated up to a lung mean radiation absorbed dose of 18 Gy at a median follow-up of 4.4 months. Conclusions Personalized predictive lung

  4. (/sup 99m/Tc)-HM-PAO SPECT in Parkinson's disease

    SciTech Connect

    Pizzolato, G.; Dam, M.; Borsato, N.; Saitta, B.; Da Col, C.; Perlotto, N.; Zanco, P.; Ferlin, G.; Battistin, L.

    1988-12-01

    Thirty-six patients affected by Parkinson's disease were studied using single photon emission computed tomography (SPECT) and (/sup 99m/Tc)-HM-PAO as a tracer. The scanning procedure was performed 16-24 h after discontinuation of specific therapy. Tracer activity ratios were determined in 10 pairs of cerebellar, cortical, and subcortical regions. Data were compared with those of 10 age-matched controls. Most of the regions examined did not show any relevant change between parkinsonian and control subjects. Notably, mean activity in striatal regions were similar in the two groups. Increased activity in caudate-putamen was found in patients who were on chronic DOPA therapy. Side-to-side asymmetries in the basal ganglia increased with the severity of the disease. Significant reductions of tracer uptake, from control values, were observed bilaterally in the parietal cortex. These deficits were more pronounced in patients with mental deterioration and in subjects who had been chronically treated with anticholinergic drugs. Parietal perfusion deficits in parkinsonian patients resemble those described in Alzheimer's dementia. These findings suggest that the heterogeneous alterations of regional cerebral blood flow (rCBF) in parkinsonian patients reflect the multifactorial pathophysiology of the disease.

  5. Filling out phenomenon with technetium-99m HM-PAO brain SPECT at the site of mild cerebral ischemia

    SciTech Connect

    Hayashida, K.; Nishimura, T.; Imakita, S.; Uehara, T.

    1989-05-01

    Although the distribution of (/sup 99m/Tc)hexamethylpropyleneamine oxime (HM-PAO) in the brain is said to be in a flow-related manner without temporal change, we present cases with leakage of (/sup 99m/Tc)HM-PAO (filling out phenomenon) in the delayed image of brain single photon emission computed tomography (SPECT) and clarify its clinical significance. The filling out phenomenon was observed in seven out of 21 cases of cerebrovascular disease and four cases of arteriovenous malformation. The leakage of (/sup 99m/Tc)HM-PAO was also confirmed by visual and semiquantitative analysis. In the pharmacokinetics of (/sup 99m/Tc)HM-PAO in the blood, the percent dose of plasma fraction at 4 hr was reduced to 54% of activity at 30 min. The percent dose of brain blood could be predicted as 3.36%/1 at 30 min and 2.35%/1 at 4 hr after correction with the hematocrit of the brain. The filling out phenomenon of (/sup 99m/Tc)HM-PAO was attributed to a significant reduction of blood activity of (/sup 99m/Tc)HM-PAO in the plasma. Since the initial image might mask reduced rCBF with an increase of rCBV, the late image would have an advantage in accurately evaluating rCBF from the clearance of (/sup 99m/Tc) HM-PAO bound to the plasma. Therefore, the filling out phenomenon of (/sup 99m/Tc)HM-PAO in late images of brain SPECT could show the area of mild cerebral ischemia accompanying cerebral vascular reserve.

  6. Dual radioisotopes simultaneous SPECT of 99mTc-tetrofosmin and 123I-BMIPP using a semiconductor detector

    PubMed Central

    Takahashi, Yasuyuki; Miyagawa, Masao; Nishiyama, Yoshiko; Kawaguchi, Naoto; Ishimura, Hayato; Mochizuki, Teruhito

    2015-01-01

    Objective(s): The energy resolution of a cadmium-zinc-telluride (CZT) solid-state semiconductor detector is about 5%, and is superior to the resolution of the conventional Anger type detector which is 10%. Also, the window width of the high-energy part and of the low-energy part of a photo peak window can be changed separately. In this study, we used a semiconductor detector and examined the effects of changing energy window widths for 99mTc and 123I simultaneous SPECT. Methods: The energy “centerline” for 99mTc was set at 140.5 keV and that for 123I at 159.0 keV. For 99mTc, the “low-energy-window width” was set to values that varied from 3% to 10% of 140.5 keV and the “high-energy-window width” were independently set to values that varied from 3% to 6% of 140.5 keV. For 123I, the “low energy-window-width” varied from 3% to 6% of 159.0 keV and the high-energy-window width from 3% to 10% of 159 keV. In this study we imaged the cardiac phantom, using single or dual radionuclide, changing energy window width, and comparing SPECT counts as well as crosstalk ratio. Results: The contamination to the 123I window from 99mTc (the crosstalk) was only 1% or less with cutoffs of 4% at lower part and 6% at upper part of 159KeV. On the other hand, the crosstalk from 123I photons into the 99mTc window mostly exceeded 20%. Therefore, in order to suppress the rate of contamination to 20% or less, 99mTc window cutoffs were set at 3% in upper part and 7% at lower part of 140.5 KeV. The semiconductor detector improves separation accuracy of the acquisition inherently at dual radionuclide imaging. In, this phantom study we simulated dual radionuclide simultaneous SPECT by 99mTc-tetrofosmin and 123I-BMIPP. Conclusion: We suggest that dual radionuclide simultaneous SPECT of 99mTc and 123I using a CZT semiconductor detector is possible employing the recommended windows. PMID:27408880

  7. Implications of CT noise and artifacts for quantitative {sup 99m}Tc SPECT/CT imaging

    SciTech Connect

    Hulme, K. W.; Kappadath, S. C.

    2014-04-15

    Purpose: This paper evaluates the effects of computed tomography (CT) image noise and artifacts on quantitative single-photon emission computed-tomography (SPECT) imaging, with the aim of establishing an appropriate range of CT acquisition parameters for low-dose protocols with respect to accurate SPECT attenuation correction (AC). Methods: SPECT images of two geometric and one anthropomorphic phantom were reconstructed iteratively using CT scans acquired at a range of dose levels (CTDI{sub vol} = 0.4 to 46 mGy). Resultant SPECT image quality was evaluated by comparing mean signal, background noise, and artifacts to SPECT images reconstructed using the highest dose CT for AC. Noise injection was performed on linear-attenuation (μ) maps to determine the CT noise threshold for accurate AC. Results: High levels of CT noise (σ ∼ 200–400 HU) resulted in low μ-maps noise (σ ∼ 1%–3%). Noise levels greater than ∼10% in 140 keV μ-maps were required to produce visibly perceptible increases of ∼15% in {sup 99m}Tc SPECT images. These noise levels would be achieved at low CT dose levels (CTDI{sub vol} = 4 μGy) that are over 2 orders of magnitude lower than the minimum dose for diagnostic CT scanners. CT noise could also lower (bias) the expected μ values. The relative error in reconstructed SPECT signal trended linearly with the relative shift in μ. SPECT signal was, on average, underestimated in regions corresponding with beam-hardening artifacts in CT images. Any process that has the potential to change the CT number of a region by ∼100 HU (e.g., misregistration between CT images and SPECT images due to motion, the presence of contrast in CT images) could introduce errors in μ{sub 140} {sub keV} on the order of 10%, that in turn, could introduce errors on the order of ∼10% into the reconstructed {sup 99m}Tc SPECT image. Conclusions: The impact of CT noise on SPECT noise was demonstrated to be negligible for clinically achievable CT parameters. Because

  8. Ibogaine labeling with 99mTc-tricarbonyl: synthesis and transport at the mouse blood-brain barrier.

    PubMed

    Tournier, Nicolas; André, Pascal; Blondeel, Sandy; Rizzo-Padoin, Nathalie; du Moulinet d'Hardemarre, Amaury; Declèves, Xavier; Scherrmann, Jean-Michel; Cisternino, Salvatore

    2009-12-01

    The (99m)Tc-tricarbonyl core may be used as an ideal tool for gamma-labeling ligands in noninvasive SPECT imaging. However, most (99m)Tc-tricarbonyl-labeled agents have difficulty crossing the blood-brain barrier (BBB). We radiolabeled the neuroactive indole ibogaine with (99m)Tc-tricarbonyl and measured its transport into the mouse brain by in situ brain perfusion. We measured the interactions of [(99m)Tc(CO)(3)-ibogaine](+) and (99m)Tc-tricarbonyl with the main BBB efflux transporters P-gp and BCRP in vitro and in vivo. Ibogaine was radiolabeled (yield: over 95%). [(99m)Tc(CO)(3)-ibogaine](+) entered the brain (K(in)) poorly (0.18 microL/g/s), at about the same rate as (99m)Tc-tricarbonyl (0.16 microL/g/s) and [(99m)Tc-sestamibi](+) (0.10 microL/g/s). The CNS tracer [(99m)Tc-HMPAO](0) entered the brain approximately 70-times higher than [(99m)Tc(CO)(3)-ibogaine](+). In vitro studies revealed that neither [(99m)Tc(CO)(3)-ibogaine](+) nor (99m)Tc-tricarbonyl ion were substrates for P-gp or BCRP. But lowering the membrane dipole potential barrier with phloretin enhanced the brain transport of [(99m)Tc(OH(2))(3)(CO)(3)](+) approximately 3-fold. Thus, ibogaine directly labeled with (99m)Tc-tricarbonyl is not suitable for CNS imaging because of its poor uptake. Brain transport is not restricted by efflux transporters but is reduced by its lipophilicity and interaction with the membrane-positive dipole potential. PMID:19492342

  9. Optimization of Imaging Parameters for SPECT scans of [99mTc]TRODAT-1 Using Taguchi Analysis

    PubMed Central

    Huang, Cheng-Kai; Wu, Jay; Cheng, Kai-Yuan; Pan, Lung-Kwang

    2015-01-01

    Parkinson’s disease (PD) is a neurodegenerative disease characterized by progressive loss of dopaminergic neurons in the basal ganglia. Single photon emission computed tomography (SPECT) scans using [99mTc]TRODAT-1 can image dopamine transporters and provide valuable diagnostic information of PD. In this study, we optimized the scanning parameters for [99mTc]TRODAT-1/SPECT using the Taguchi analysis to improve image quality. SPECT scans were performed on forty-five healthy volunteers according to an L9 orthogonal array. Three parameters were considered, including the injection activity, uptake duration, and acquisition time per projection. The signal-to-noise ratio (SNR) was calculated from the striatum/occipital activity ratio as an image quality index. Ten healthy subjects and fifteen PD patients were used to verify the optimal parameters. The estimated optimal parameters were 962 MBq for [99mTc]TRODAT-1 injection, 260 min for uptake duration, and 60 s/projection for data acquisition. The uptake duration and time per projection were the two dominant factors which had an F-value of 18.638 (38%) and 25.933 (53%), respectively. Strong cross interactions existed between the injection activity/uptake duration and injection activity/time per projection. Therefore, under the consideration of as low as reasonably achievable (ALARA) for radiation protection, we can decrease the injection activity to 740 MBq. The image quality remains almost the same for clinical applications. PMID:25790100

  10. Evaluation of Simultaneous Dual-radioisotope SPECT Imaging Using 18F-fluorodeoxyglucose and 99mTc-tetrofosmin

    PubMed Central

    Takahashi, Yasuyuki; Mochiki, Mizuki; Koyama, Keiko; Ino, Toshihiko; Yamaji, Hiroyuki; Kawakami, Atsuko

    2016-01-01

    Objective(s): Use of a positron emission tomography (PET)/single-photon emission computed tomography (SPECT) system facilitates the simultaneous acquisition of images with fluorine-18 fluorodeoxyglucose (18F-FDG) and technetium (99mTc)-tetrofosmin. However, 18F has a short half-life, and 511 keV Compton-scattered photons are detected in the 99mTc energy window. Therefore, in this study, we aimed to investigate the consequences of these facts. Methods: The crosstalk correction for images in the 99mTc energy window involved the dual energy window (DEW) subtraction method. In phantom studies, changes in the count of uniform parts in a phantom (due to attenuation from decay), signal detectability in the hot-rod part of the phantom, and the defect contrast ratio in a cardiac phantom were examined. Results: For 18F-FDG in the step-and-shoot mode, nearly a 9% difference was observed in the count of projection data between the start and end positions of acquisition in the uniform part of the phantom. Based on the findings, the detectability of 12 mm hot rods was relatively poor. In the continuous acquisition mode, the count difference was corrected, and detectability of the hot rods was improved. The crosstalk from 18F to the 99mTc energy window was approximately 13%. In the cardiac phantom, the defect contrast in 99mTc images from simultaneous dual-radionuclide acquisition was improved by approximately 9% after DEW correction; the contrast after correction was similar to acquisition with 99mTc alone. Conclusion: Based on the findings, the continuous mode is useful for 18F-FDG acquisition, and DEW crosstalk correction is necessary for 99mTc-tetrofosmin imaging. PMID:27408894

  11. 99mTc-MDP uptake in SPECT/CT by a bladder hernia simulating inguinal metastasis: A case report

    PubMed Central

    JI, TIEFENG; GAO, DAPENG; CHEN, BIN; WANG, RENJIE; GAO, SHI

    2016-01-01

    A 72-year-old male with a history of prostate cancer and high prostate specific antigen levels underwent 99mtechnetium-methylene diphosphonate (99mTc-MDP) single-photon emission computed tomography/computed tomography (SPECT/CT), to identify bone metastasis. The patient possessed no previous history of serious illnesses or surgical procedures and no family history of malignancies. A whole-body CT scan revealed an intense MDP uptake in the right inguinal region on the anterior view, but not in the posterior view, which was suspected to be a metastatic lesion. However, there was no evidence of bone metastasis on the CT scan. In addition, an increased 99mTc-MDP uptake was indicated on the SPECT images in the right inguinal region, which appeared to be separate from the main bladder activity. CT images of the pelvis revealed an inferior tongue-like extension of the bladder into the right inguinal region. Fused SPECT/CT axial images indicated the circular accumulation of the 99mTc-MDP in the medial right groin, with well-defined walls that connected the accumulation to the bladder. The final diagnosis was a bladder hernia (T2N0M0), which may have been responsible for the misdiagnosis of bone metastasis due to the use of radiopharmaceuticals (99mTc-MDP) that were mainly excreted through urination. Considering the comprehensive situation of the patient, radical prostatectomy was performed. The bladder hernia was subsequently monitored by follow-up examination every 3 months, and remains alive and under follow-up to date. PMID:26893749

  12. Tl-201 and Tc-99m-Sestamibi SPECT for brain tumor detection: Comparison using MRI coregistration

    SciTech Connect

    Darcourt, J.; Itti, L.; Chang, L.

    1994-05-01

    Tl-201 (Tl) brain SPECT has been validated for the differential diagnosis of high versus low grade gliomas and recurrence versus radiation necrosis. We compared this technique to Tc-99m-Sestamibi (MIBI) SPECT in 9 patients (pts) with brain tumors using MRI coregistration. Pts were injected with 4 mCi of Tl and brain SPECT was performed using a dedicated brain system. This was immediately following by an injection of 20 mCi of MIBI and a brain SPECT using the same camera and with the pt in the same position. Four pts were studied for the diagnosis of radiation necrosis vs. tumor recurrence (2 had biopsy proven recurrence); 5 pts were studied for primary tumor evaluation: 2 meningiomas, 1 oligodendroglioma, 1 low-grade astrocytoma, 1 cysticercosis. Coregistration was performed for every pt by 3D surface fitting of the inner skull MIBI contour to the MRI brain surface extracted automatically. ROIs were drawn on the MRI and applied to the coregistered MIBI and Tl images for tumor to non-tumor ratios T/NT calculations. There was a tight correlation between MIBI and Tl T/NT (r-0.96) and a 1.5 threshold separated radiation necrosis from recurrence and low from high grade primary tumors. Therefore, the data already available on Tl brain tumor imaging can be used with MIBI SPECT with the advantage of a better image quality (2.5 to 4 times more counts).

  13. [ECG-gated myocardial SPECT with 99mTc-MIBI in patients with right ventricular infarction].

    PubMed

    Kumita, S; Mizumura, S; Cho, K; Kijima, T; Kumazaki, T; Tetsuou, Y; Sakai, S; Sano, J; Kusama, Y; Munakata, K

    1996-06-01

    Although 99mTc-pyrophosphate (PYP) myocardial scintigraphy has so far been widely used for the diagnosis of right ventricular infarction, PYP accumulation disappears within one week or so. To evaluate the myocardial condition of the right ventricle alternatively, myocardial SPECT with 99mTc-MIBI was performed in 16 patients with acute inferior left ventricular infarction, and ECG-gated myocardial SPECT data acquisition was accompanied in 14 of 16 patients. Right ventricular perfusion defect was observed in 4 of 16 patients (RVI (+) group), and the remains were negative (RVI (-) group). Then, right ventricular count increase rate (RV %WT) of MIBI from end-diastole to end-systole was calculated using an automated method which was developed for quantification of wall thickening in our laboratory. The RV %WT was conceived to be an objective index representing right ventricular contractility. RVI (+) group (n = 3) as compared with RVI (-) group (n = 11) had significant lower RV %WT (26.7 +/- 3.2 vs. 49.6 +/- 14.2; p < 0.01). In conclusion, ECG-gated myocardial SPECT with MIBI was considered to be useful for assessment of myocardial perfusion and contractility of right ventricle. PMID:8741508

  14. A diagnostic dilemma of atypical gallbladder appearance on Tc-99m HIDA cholescintigraphy resolved with SPECT/CT.

    PubMed

    Sood, Ravi; Murguia, Jeff; Graham, Michael M; Bushnell, David; Squires, Shayne; Laroia, Sandeep T; Bansal, Anish

    2011-02-01

    Tc-99m HIDA cholescintigraphy is the diagnostic procedure of choice for acute cholecystitis. Acute cholecystitis is associated in vast majority of the cases with cystic duct obstruction. The demonstration of presence (cystic duct patency) or absence (cystic duct obstruction) of visualization of the gallbladder on cholescintigraphy is critical to the diagnosis of acute cholecystitis. The visualization of the gallbladder rules out acute cholecystitis in most of the cases. Although, in most cases, determination of visualization or nonvisualization of gallbladder is straight forward, occasionally it can be challenging. We describe a patient with suspected acute cholecystitis, in whom an unusual appearance of the gallbladder on hepatobiliary scintigraphy was clarified with SPECT/CT, an approach that is rarely used in Tc-99m HIDA cholescintigraphy. PMID:21220991

  15. Benign incidental findings of osteopoikilosis on Tc-99m MDP bone SPECT/CT: A case report and literature review.

    PubMed

    Tsai, Szu-Ying; Wang, Shan-Ying; Shiau, Yu-Chien; Wu, Yen-Wen

    2016-06-01

    Osteopoikilosis is a benign but rare condition characterized by bone islands throughout the osseous tissue, which could be easily confused with bone metastasis. We present a case of a 37-year-old man presented to orthopedic outpatient clinic with right hip pain for 2 weeks. There were multiple, small punctate lesions scattered throughout the skeleton on radiograph. Subsequent Tc-99m methylene diphosphonate (MDP) bone scan with pelvic single-photon emission computed tomography (SPECT)/computed tomography (CT) showed multiple enostoses without abnormal focal MDP uptake. Therefore, clinical diagnosis was compatible with osteopoikilosis while bone metastasis was unlikely. The symptoms then improved by conservative treatments. Osteopoikilosis is usually an incidental finding on radiograph or CT, and a normal MDP confirmed the diagnosis by excluding bone metastasis. It is important for clinicians to recognize the specific image features to prevent further unnecessary interventions. In addition, bone SPECT/CT could also make the diagnosis in one step. PMID:27281099

  16. Evaluation of cerebral hemodynamic changes by Tc-99m HMPAO SPECT after radiosurgery of small arteriovenous malformations (AVM)

    SciTech Connect

    Liu, R.S.; Yeh, S.H.; Pan, H.C.

    1994-05-01

    Treatment of small AVMs (<3 cm) by stereotaxic radio-surgery using gamma unit has been a promising noninvasive method. However, cerebral hemodynamic changes after gamma unit treatment is obscure. This study assessed the effect of radiosurgery on the regional cerebral blood flow (rCBF) in treatment of small AVMs. Nine patients (pts) with small AVMs were imaged with SPECT using Tc-99m HMPAO prior to stereotactic radio-surgery. The pts were treated with a Leskell gamma unit with doses of radiation in the range of 36 Gy to 44 Gy at target center. All pts underwent HMPAO SPECT scans about 3 months after radiosurgery. Pts were also studied with CT/MR scans. Pre treatment HMPAO SPECT showed decreased rCBF in the regions of nidi of AVMs of all pts and in the adjacent zones in 2 pts. Increased rCBF surrounding the nidus was noted in 2 AVMs. After treatment, rCBF of 2 pts returned to normal, 6 pts showed much improvement of rCBF and 1 remained no change. No more perfusion abnormalities were seen in the adjacent zones of all AVMs after radiosurgery. Cross cerebellar diaschisis noted in one case also disappeared after radiosurgery. Post treatment CT/MR scans showed slightly decrease in size of AVMs in 6 pts. All pts had great improvement after treatment. Normalization of rCBF correlated well with improvements in the neurological symptoms. In conclusion, comparison of pre and post treatment Tc-99m HMPAO SPECT scans were useful in evaluating the effectiveness of gamma unit radiosurgery on small AVMs.

  17. Attenuation compensation in TC-99M SPECT brain imaging: Use of attenuation maps derived from tranmission versus emission data

    SciTech Connect

    Pan, T.S.; Licho, R.; Penney, B.C.

    1994-05-01

    This study compares reconstructions of Tc-99m brain SPECT studies made using two methods of estimating the attenuation map: (1) transmission scanning, and (2) segmenting reconstructions of emission data and assigning attenuation coefficient values. A three-head SPECT system with fan beam collimators was used. Transmission scanning was performed using a line source at the focal line of a fan beam collimator right after the regular emission scan. The higher attenuation of the skull and the lower attenuation in the sinus cavities were identifiable despite the noise in the reconstructed transmission data due to: (1) the contamination of the transmission data by emission photons, (2) the maximum acquisition count rate imposed by the SPECT system, and (3) the clinical scanning time. Emission data were recorded using both photopeak and Compton scatter energy windows. Outlines of the head and the maxillary sinus could be obtained using only the Compton scatter reconstructions, whereas identifying the skull regions and the frontal sinus required the photopeak data as well. We placed appropriate linear attenuation coefficients in the soft tissue, bone, sinus and air regions (0.15,. 0.22, 0, and 0 cm{sup -1}) and blurred this attenuation map with a Gaussian kernel of about 0.2 cm standard deviation to obtain the attenuation map based on the emission data. Reconstructions were computed using the maximum likelihood expectation maximization algorithm with Siddon`s ray-tracing algorithm. Reconstructions based on the two attenuation maps were compared quantitatively on the patient data. The differences noted were quite small. These results imply that attenuation correction based on emission data alone may be adequate for Tc-99m SPECT brain imaging.

  18. Detection of breast cancer microcalcification using 99mTc-MDP SPECT or Osteosense 750EX FMT imaging

    PubMed Central

    Felix, Dayo D.; Gore, John C.; Yankeelov, Thomas E.; Peterson, Todd E.; Barnes, Stephanie; Whisenant, Jennifer; Weis, Jared; Shoukouhi, Sepideh; Virostko, John; Nickels, Michael; McIntyre, J. Oliver; Sanders, Melinda; Abramson, Vandana; Tantawy, Mohammed N.

    2015-01-01

    Background In previous work, we demonstrated the presence of hydroxyapetite (type II microcalcification), HAP, in triple negative MDA-MB-231 breast cancer cells. We used 18F-NaF to detect these types of cancers in mouse models as the free fluorine, 18F−, binds to HAP similar to bone uptake. In this work, we investigate other bone targeting agents and techniques including 99mTc-MDP SPECT and Osteosense 750EX FMT imaging as alternatives for breast cancer diagnosis via targeting HAP within the tumor microenvironment. Methods Thirteen mice were injected subcutaneously in the right flank with 106 MDA-MB-231 cells. When the tumor size reached ~0.6 cm3, mice (n = 9) were injected with ~37 MBq of 99mTc-MDP intravenously and then imaged one hour later in a NanoSPECT/CT or injected intravenously with 4 nmol/g of Osetosense 750EX and imaged 24 hours later in an FMT (n = 4). The imaging probe concentration in the tumor was compared to that of muscle. Following SPECT imaging, the tumors were harvested, sectioned into 10 µm slices, and underwent autoradiography or von Kossa staining to correlate 99mTc-MDP binding with HAP distribution within the tumor. The SPECT images were normalized to the injected dose and regions-of-interest (ROIs) were drawn around bone, tumor, and muscle to obtain the radiotracer concentration in these regions in units of percent injected dose per unit volume. ROIs were drawn around bone and tumor in the FMT images as no FMT signal was observed in normal muscle. Results Uptake of 99mTc-MDP was observed in the bone and tumor with little or no uptake in the muscle with concentrations of 11.34 ± 1.46 (mean ± SD), 2.22 ± 0.95, and 0.05 ± 0.04 %ID/cc, respectively. Uptake of Osteosense 750EX was also observed in the bone and tumor with concentrations of 0.35 ± 0.07 (mean ± SD) and 0.04 ± 0.01 picomoles, respectively. No FMT signal was observed in the normal muscle. There was no significant difference in the bone-to-tumor ratio between the two

  19. Tc99m/T1201 cross-talk corrections on a dedicated cardiac CZT SPECT camera

    NASA Astrophysics Data System (ADS)

    Chiasson, Stephanie

    Single Photon Emission Computed Tomography (SPECT) is a standard method for evaluating heart disease. A new dedicated cardiac camera with CZT detectors offers improved energy resolution and sensitivity compared to standard SPECT systems. Simultaneous Tc99m/T1201 protocols are fast, but correction for cross-talk between isotopes is necessary to achieve good image quality. The Triple-Energy-Window (TEW) correction method is easy to implement and provides accurate scatter estimation in single-isotope studies. We retrospectively assessed the cross-talk correction using clinically acquired single-isotope studies: 52 T1201 studies and 52 Tc99m-tetrofosmin studies, matched by gender and BMI. Projection data from Tl-stress and Tc-rest studies were combined to create contaminated data before reconstruction. TEW corrections were evaluated in both primary energy windows. Modifications to the corrections were required. The modified approach results in residual cross-talk as low as 2% but high noise levels were present in the corrected images. Further modifications are needed to reduce noise.

  20. Compartmental analysis of technetium-99m-teboroxime kinetics employing fast dynamic SPECT at rest and stress

    SciTech Connect

    Chiao, P.C.; Ficaro, E.P.; Dayaniki, F.

    1994-08-01

    The authors have examined the feasibility of compartmental analysis of {sup 99m}Tc-teboroxime kinetics in measuring physiological changes in response to adenosine-induced coronary vasodilation. To evaluate the effect of tracer recirculation on {sup 99m}Tc-teboroxime kinetics in the myocardium, they also compared compartmental analysis with washout analysis (monoexponertial fitting), which does not account for this effect. Eight healthy male volunteers were imaged using fast dynamic SPECT protocols (5 sec per tomographic image) at rest and during adenosine infusion. A two-compartment model was used and compartmental parameters K1 and k2 (characterizing the diffusion of {sup 99m}Tc-teboroxime from the blood to the myocardium and from the myocardium to the blood, respectively) were fitted from myocardial time-activity curves and left ventricular input functions. Both K1 and washout estimates for the whole left ventricular myocardium changed significantly in response to coronary vasodilation. Mean stress-to-rest (S/R) ratios were almost two times higher for K1 (S/R = 2.7 {plus_minus} 1.1) than for washout estimates (S/R = 1.5 {plus_minus} 0.3). Estimation of K1 for all local regions, except the septal wall, is feasible because variations in K1 estimates for all local regions, except the septum during stress, are comparable with those for the global region. The authors conclude that quantitative compartmental analysis of {sup 99m}Tc-teboroxime kinetics provides a sensitive indicator for changes in response to adenosine-induced coronary vasodilation. 39 refs., 7 figs., 1 tab.

  1. A comparison of rat SPECT images obtained using 99mTc derived from 99Mo produced by an electron accelerator with that from a reactor

    NASA Astrophysics Data System (ADS)

    Galea, R.; Wells, R. G.; Ross, C. K.; Lockwood, J.; Moore, K.; Harvey, J. T.; Isensee, G. H.

    2013-05-01

    Recent shortages of molybdenum-99 (99Mo) have led to an examination of alternate production methods that could contribute to a more robust supply. An electron accelerator and the photoneutron reaction were used to produce 99Mo from which technetium-99m (99mTc) is extracted. SPECT images of rat anatomy obtained using the accelerator-produced 99mTc with those obtained using 99mTc from a commercial generator were compared. Disks of 100Mo were irradiated with x-rays produced by a 35 MeV electron beam to generate about 1110 MBq (30 mCi) of 99Mo per disk. After target dissolution, a NorthStar ARSII unit was used to separate the 99mTc, which was subsequently used to tag pharmaceuticals suitable for cardiac and bone imaging. SPECT images were acquired for three rats and compared to images for the same three rats obtained using 99mTc from a standard reactor 99Mo generator. The efficiency of 99Mo-99mTc separation was typically greater than 90%. This study demonstrated the delivery of 99mTc from the end of beam to the end user of approximately 30 h. Images obtained using the heart and bone scanning agents using reactor and linac-produced 99mTc were comparable. High-power electron accelerators are an attractive option for producing 99Mo on a national scale.

  2. Artificial neural network classifier for the diagnosis of Parkinson's disease using [99mTc]TRODAT-1 and SPECT

    NASA Astrophysics Data System (ADS)

    Acton, Paul D.; Newberg, Andrew

    2006-06-01

    Imaging the dopaminergic neurotransmitter system with positron emission tomography (PET) or single photon emission tomography (SPECT) is a powerful tool for the diagnosis of Parkinson's disease (PD). Previous studies have indicated that human observers have a diagnostic accuracy similar to conventional ROI analysis of SPECT imaging data. Consequently, it has been hypothesized that an artificial neural network (ANN), which can mimic the pattern recognition skills of human observers, may provide similar results. A set of patients with PD, and normal healthy control subjects, were studied using the dopamine transporter tracer [99mTc]TRODAT-1 and SPECT. The sample was comprised of 81 patients (mean age ± SD: 63.4 ± 10.4 years; age range: 39.0-84.2 years) and 94 healthy controls (mean age ± SD: 61.8 ± 11.0 years; age range: 40.9-83.3 years). The images were processed to extract the striatum and the striatal pixel values were used as inputs to a three-layer ANN. The same set of data was used to both train and test the ANN, in a 'leave one out' procedure. The diagnostic accuracy of the ANN was higher than any previous analysis method applied to the same data (94.4% total accuracy, 97.5% specificity and 91.4% sensitivity). However, it should be stressed that, as with all applications of an ANN, it was difficult to interpret precisely what triggers in the images were being detected by the network.

  3. Pattern of brain blood perfusion in tinnitus patients using technetium-99m SPECT imaging

    PubMed Central

    Mahmoudian, Saeid; Farhadi, Mohammad; Gholami, Saeid; Saddadi, Fariba; Karimian, Ali Reza; Mirzaei, Mohammad; Ghoreyshi, Esmaeel; Ahmadizadeh, Majid; Lenarz, Thomas

    2012-01-01

    Background and Purpose: Tinnitus is associated with an increased activity in central auditory system as demonstrated by neuroimaging studies. Brain perfusion scanning using single photon emission computed tomography (SPECT) was done to understand the pattern of brain blood perfusion of tinnitus subjects and find the areas which are mostly abnormal in these patients. Materials and Methods: A number of 122 patients with tinnitus were enrolled to this cross-sectional study. They underwent SPECT and magnetic resonance imaging (MRI) of brain, and the images were fused to find the regions with abnormal perfusion. Results: SPECT scan results were abnormal in 101 patients (83%). Most patients had bilateral abnormal perfusion (N = 65, 53.3%), and most subjects had abnormality in middle-temporal gyrus (N = 83, 68%) and temporoparietal cortex (N = 46, 37.7%). Patients with multifocal involvement had the least mean age than other 2 groups (patients with no abnormality and unifocal abnormality) (P value = 0.045). Conclusions: Brain blood perfusion pattern differs in patient with tinnitus than others. These patients have brain perfusion abnormality, mostly in auditory gyrus (middle temporal) and associative cortex (temporoparietal cortex). Multifocal abnormalities might be due to more cognitive and emotional brain centers involvement due to tinnitus or more stress and anxiety of tinnitus in the young patients. PMID:23267375

  4. Quantitation of brain perfusion with {sup 99m}{Tc}-bicisate and single SPECT scan: Comparison with microsphere measurements

    SciTech Connect

    Pupi, A.; De Cristofaro, T.R.; Passeri, A.; Castagnoli, A.; Bacciottini, L.; Bottoncetti, A.; Dal Pozzo, G.; Santoro, G.M.; Antoniucci, D.

    1994-01-01

    This study describes and validates in a preliminary manner a method to measure the steady-state influx constant (K{sub 1}) of {sup 99m}{Tc}-bicisate with one single photon emission computed tomography (SPECT) scan. The method is based on the analysis of the arterial concentration of the radioactivity. The results of this quantitation procedure were compared with regional CBF (rCBF) measurements made using {sup 99m}{Tc}-microspheres (MI). Two quantitative indexes of perfusion, fractional brain uptake (FBU) and normalized (with cerebellum) brain uptake (NBU), were also evaluated. Two SPECT studies were performed on seven cardiovascular patients who had no signs of neurological disease. In the first of these, {sup 99m}{Tc}-bicisate was used, while in the other, which was performed 2 days later, MI were injected into the left heart ventricle. The values of the FBU, NBU, and K{sub 1} of {sup 99m}{Tc}-bicisate were calculated in several gray and white matter brain regions of interest (ROIs) and compared with the rCBF values measured with MI in coupled ROIs. Mean FBU values were 0.00008 {+-} 0.00002 and 0.00004 {+-} 0.00001 in the gray and the white matter, respectively. Mean NBU values were 0.99 {+-} 0.04 and 0.54 {+-} 0.05, mean K{sub 1} values were 0.36 {+-} 0.06 and 0.19 {+-} 0.03 ml g{sup {minus}1} min{sup {minus}1} and mean rCBF values were 0.51 {+-} 0.04 and 0.27 {+-} 0.04 ml g{sup {minus}1} min{sup {minus}1} in gray and white matter, respectively. Analysis of variance of the regression gave different F values for the regressions with rCBF of FBU (F = 19, n = 126), NBU (F = 289, n = 112), and K{sub 1}(F = 117, n = 112), and K{sub 1}(F = 117, n = 126). The regression of K{sub 1} versus rCBF was K{sub 1} = 0.08 {+-} 0.55 rCBF. 25 refs., 5 figs., 2 tabs.

  5. Normal qualitative and quantitative Tc-99m sestamibi myocardial SPECT: spectrum of intramyocardial distribution during exercise and at rest.

    PubMed

    Lette, J; Caron, M; Cerino, M; McNamara, D; Metayer, S; D'Aoust, S; Eybalin, M C; Levesseur, A; Grégoire, J; Arsenault, A

    1994-04-01

    Exercise myocardial perfusion imaging with Tc-99m sestaMIBI is routinely used to detect underlying coronary stenoses. Ischemia is diagnosed in regions that display decreased tracer uptake during exercise as compared to rest. Tc-99m sestaMIBI SPECT images of 42 healthy volunteers were assessed both qualitatively (tomographic slices) and quantitatively (sectored polar map) for potential sources of misinterpretation. On the myocardial tomographic slices, the most common culprit artifacts were diaphragmatic attenuation and bowel interposition, which caused fixed or reversible "perfusion defects" in the inferior and posterior regions (in 19/35 abnormal segments), and artifacts related to the presence and shift of hot spots (observed in 11/28 men; in women, they were more difficult to demonstrate because of the overriding effect of breast attenuation). Hot spots shifts between exercise and rest usually resulted in pseudo-reversible defects in the anterolateral and lateral walls. The quantified polar map display of the myocardium showed a physiologic decrease in sestaMIBI activity in the basal anterolateral and basal posterolateral areas in men during exercise. There are many normal variants that may mimic coronary artery disease on tomographic sestaMIBI images. Before reporting an area of decreased activity as either a fixed or reversible perfusion defect, the interpreter should ensure that it does not represent an artifact or a normal variation in the intramyocardial distribution of sestaMIBI during exercise. PMID:8004868

  6. Dual isotope cross-talk correction in Tc-99m/In-111 small-animal SPECT

    NASA Astrophysics Data System (ADS)

    Timmins, Rachel

    Dual-isotope imaging via energy discrimination is a major strength of SPECT but image quality is degraded by cross-talk interference. Direct application of clinically developed cross-talk correction techniques in small-animals is not ideal. Reduced subject size may allow adequate quantification with simpler cross-talk correction methods. This study evaluated four simple cross-talk correction methods for In-111/Tc--99m small-animal imaging: triple energy window (TEW), applied pre- and post-correction, convolution subtraction, and a vendor-supplied correction. Each method was evaluated using a three-syringe phantom filled with either Tc-99m, In-111, or a mixture of the two at five different ratios. The optimal method was tested on in-vivo rat images. A modified TEW applied in projection space visually provided the best removal of In-111 cross-talk and reduced it quantitatively by 96%. The mixed syringe ratios were recovered to within 5%. In-vivo testing provided inconclusive results indicating that a true dual-isotope study is still necessary.

  7. Sci—Thur PM: Imaging — 05: Calibration of a SPECT/CT camera for quantitative SPECT with {sup 99m}Tc

    SciTech Connect

    Gaudin, Émilie; Montégiani, Jean-François; Després, Philippe; Beauregard, Jean-Mathieu

    2014-08-15

    While quantitation is the norm in PET, it is not widely available yet in SPECT. This work's aim was to calibrate a commercially available SPECT/CT system to perform quantitative SPECT. Counting sensitivity, dead-time (DT) constant and partial volume effect (PVE) of the system were assessed. A dual-head Siemens SymbiaT6 SPECT/CT camera equipped with low energy high-resolution collimators was studied. {sup 99m}Tc was the radioisotope of interest because of its wide usage in nuclear medicine. First, point source acquisitions were performed (activity: 30–990MBq). Further acquisitions were then performed with a uniform Jaszczak phantom filled with water at high activity (25–5000MBq). PVE was studied using 6 hot spheres (diameters: 9.9–31.2 mm) filled with {sup 99m}Tc (2.8MBq/cc) in the Jaszczak phantom, which was: (1) empty, (2) water-filled and (3) water-filled with low activity (0.1MBq/cc). The data was reconstructed with the Siemens's Flash3D iterative algorithm with 4 subsets and 8 iterations, attenuation-correction (AC) and scatter-correction (SC). DT modelling was based on the total spectrum counting rate. Sensitivity was assessed using AC-SC reconstructed SPECT data. Sensitivity and DT for the sources were 99.51±1.46cps/MBq and 0.60±0.04µs. For the phantom, sensitivity and DT were 109.9±2.3cps/MBq and 0.62±0.13µs. The recovery-coefficient varied from 5% for the 9.9mm, to 80% for the 31.2mm spheres. With our calibration methods, both sensitivity and DT constant of the SPECT camera had little dependence on the object geometry and attenuation. For small objects of known size, recovery-coefficient can be applied to correct PVE. Clinical quantitative SPECT appears to be possible and has many potential applications.

  8. Model-based correction for scatter and tailing effects in simultaneous 99mTc and 123I imaging for a CdZnTe cardiac SPECT camera

    NASA Astrophysics Data System (ADS)

    Holstensson, M.; Erlandsson, K.; Poludniowski, G.; Ben-Haim, S.; Hutton, B. F.

    2015-04-01

    An advantage of semiconductor-based dedicated cardiac single photon emission computed tomography (SPECT) cameras when compared to conventional Anger cameras is superior energy resolution. This provides the potential for improved separation of the photopeaks in dual radionuclide imaging, such as combined use of 99mTc and 123I . There is, however, the added complexity of tailing effects in the detectors that must be accounted for. In this paper we present a model-based correction algorithm which extracts the useful primary counts of 99mTc and 123I from projection data. Equations describing the in-patient scatter and tailing effects in the detectors are iteratively solved for both radionuclides simultaneously using a maximum a posteriori probability algorithm with one-step-late evaluation. Energy window-dependent parameters for the equations describing in-patient scatter are estimated using Monte Carlo simulations. Parameters for the equations describing tailing effects are estimated using virtually scatter-free experimental measurements on a dedicated cardiac SPECT camera with CdZnTe-detectors. When applied to a phantom study with both 99mTc and 123I, results show that the estimated spatial distribution of events from 99mTc in the 99mTc photopeak energy window is very similar to that measured in a single 99mTc phantom study. The extracted images of primary events display increased cold lesion contrasts for both 99mTc and 123I.

  9. Superfluorinated PEI Derivative Coupled with (99m) Tc for ASGPR Targeted (19) F MRI/SPECT/PA Tri-Modality Imaging.

    PubMed

    Guo, Zhide; Gao, Mengna; Song, Manli; Li, Yesen; Zhang, Deliang; Xu, Duo; You, Linyi; Wang, Liangliang; Zhuang, Rongqiang; Su, Xinhui; Liu, Ting; Du, Jin; Zhang, Xianzhong

    2016-07-01

    Fluorinated polyethylenimine derivative labeled with radionuclide (99m) Tc is developed as a (19) F MRI/SPECT/PA multifunctional imaging agent with good asialoglycoprotein receptors (ASGPR)-targeting ability. This multifunctional agent is safe and suitable for (19) F MRI/SPECT/PA imaging and has the potential to detect hepatic diseases and to assess liver function, which provide powerful support for the development of personalized and precision medicine. PMID:27159903

  10. Comparison of facet joint activity on 99mTc-MDP SPECT/CT with facet joint signal change on MRI with fat suppression

    PubMed Central

    Lehman, Vance T.; Murphy, Robert C.; Schenck, Louis A.; Carter, Rickey E.; Johnson, Geoffrey B.; Kotsenas, Amy L.; Morris, Jonathan M.; Nathan, Mark A.; Wald, John T.; Maus, Timothy P.

    2016-01-01

    PURPOSE We compared signal change on magnetic resonance imaging (MRI) with fat suppression and bone scan activity of lumbar facet joints to determine if these two imaging findings are correlated. METHODS We retrospectively identified all patients who underwent imaging of the lumbar spine for pain evaluation using both technetium-99m methylene disphosphonate single-photon emission computed tomography/computed tomography (99mTc-MDP SPECT/CT) and MRI with at least one fat-suppressed T2- or T1-weighted sequence with gadolinium enhancement within a 180-day interval, at our institution between 1 January 2008 and 19 February 2013. Facet joint activity on 99mTc-MDP SPECT/CT and peri-facet signal change on MRI were rated as normal or increased. Agreement between the two examination types were determined with the κ and prevalence-adjusted bias-adjusted κ (PABAK) statistics. RESULTS This study included 60 patients (28 male, 47%), with a mean age of 49±19.7 years (range, 12–93 years). The κ value indicated no agreement between 99mTc-MDP SPECT/CT and MRI (κ=−0.026; 95% confidence interval: −0.051, 0.000). The PABAK values were fair to high at each spinal level, which suggests that relatively low disease prevalence lowered the κ values. Together, the κ and PABAK values indicate that there is some degree of intermodality agreement, but that it is not consistent. CONCLUSION Overall, facet joint signal change on fat-suppressed MRI did not always correlate with increased 99mTc-MDP SPECT/CT activity. MRI and 99mTc-MDP SPECT/CT for facet joint evaluation should not be considered interchangeable examinations in clinical practice or research. PMID:27035592

  11. (99m)Tc SPECT imaging agent based on cFLFLFK for the detection of FPR1 in inflammation.

    PubMed

    Stasiuk, Graeme J; Holloway, Paul M; Rivas, Charlotte; Trigg, William; Luthra, Sajinder Kaur; Morisson Iveson, Veronique; Gavins, Felicity N E; Long, Nicholas J

    2015-03-21

    Non-invasive imaging of the inflammatory process can provide great insight into a wide variety of disease states, aiding diagnosis, evaluation and effective targeted treatment. During inflammation, blood borne leukocytes are recruited, through a series of activation and adhesion steps, to the site of injury or infection where they migrate across the blood vessel wall into the tissue. Thus, tracking leukocyte recruitment and accumulation provides a dynamic and localised read out of inflammatory events. Current leukocyte imaging techniques require ex vivo labelling of patient blood, involving laborious processing and potential risks to both patient and laboratory staff. Utilising high affinity ligands for leukocyte specific receptors may allow for injectable tracers that label leukocytes in situ, omitting potentially hazardous ex vivo handling. Formyl peptide receptors (FPRs) are a group of G-protein coupled receptors involved in the chemotaxis and inflammatory functioning of leukocytes. Highly expressed on leukocytes, and up-regulated during inflammation, these receptors provide a potential target for imaging inflammatory events. Herein we present the synthesis and initial in vitro testing of a potential Single Photon Emission Computed Tomography (SPECT) leukocyte tracer. The FPR1 antagonist cFLFLFK-NH2, which displays high affinity with little physiological effect, has been linked via a PEG motif to a (99m)Tc chelate. This tracer shows in vitro binding to human embryonic kidney cells expressing the FPR1 receptor, and functional in vitro tests reveal cFLFLFK-NH2 compounds to have no effect on inflammatory cell functioning. Overall, these data show that (99m)Tc.cFLFLFK-NH2 may be a useful tool for non-invasive imaging of leukocyte accumulation in inflammatory disease states. PMID:25603955

  12. The key role of 99mTc-MIBI SPECT/CT in the diagnosis of parathyroid adenoma: a case report.

    PubMed

    Li, Qing; Pan, Jiemin; Luo, Quanyong; Wang, Yan; Bao, Yuqian; Jia, Weiping

    2015-06-01

    The concomitant occurrence of primary hyperparathyroidism (PHPT) due to parathyroid adenoma and papillary thyroid carcinoma (PTC) is not common. The co-occurrence of parathyroid tumors and thyroid diseases can lead to misdiagnosis owing to mutual interference of imaging in the early period of disease. The most commonly used imaging techniques for the preoperative localization of parathyroid and thyroid adenomas are technetium-99m sestamibi (99mTc-MIBI) scintigraphy and ultrasonography of the neck. Recently, 99mTc-MIBI single-photon emission computed tomography associated with computed tomography scintigraphy (SPECT/CT) has been used to detect PHPT, and its diagnostic value is being evaluated. Herein, we report a patient with an unusual co-occurrence of parathyroid adenoma and multiple thyroid diseases, including papillary thyroid carcinoma, thyroid adenoma and lymphocytic thyroiditis, which were localized with 99mTc-MIBI SPECT/CT and confirmed surgically. We suggest that 99mTc-MIBI SPECT/CT can play an important role in the diagnosis of parathyroid and thyroid lesions. PMID:26154096

  13. Crossed Fused Renal Ectopia: Presentations on 99mTc-MAG3 Scan, 99mTc-DMSA SPECT, and Multidetector CT.

    PubMed

    Moon, Eun Ha; Kim, Min-Woo; Kim, Young Jun; Sun, In O

    2015-10-01

    Crossed renal ectopia is an uncommon developmental anomaly in which both kidneys are located on the same side of the body. The present case describes a 20-year-old man who underwent the military entrance physical examination. The ultrasound showed the right kidney in normal site with slightly increased size, but the left kidney was not identified. Tc-MAG3 scan showed a single kidney with 2 ureters, and the orifices of the ureters were connected at both sides of bladder. Tc-DMSA SPECT and contrast-enhanced multidetector CT were performed and revealed crossed fused renal ectopia. PMID:26252333

  14. Simultaneous Technetium-99m/Thallium-201 SPECT Imaging with Model-Based Compensation for Cross-Contaminating Effects

    PubMed Central

    Kadrmas, Dan J.; Frey, Eric C.; Tsui, Benjamin M.W.

    2009-01-01

    Simultaneous acquisition of dual-isotope SPECT data offers a number of advantages over separately acquired data; however, simultaneous acquisition can result in cross-contamination between isotopes. In this work we propose and evaluate two frameworks for iterative model-based compensation of cross-contamination in dual-isotope SPECT. The methods were applied to cardiac imaging with Technetium-99m-sestamibi and Thallium-201, and they were compared to a subtraction-based compensation method using a cross-talk estimate obtained from an auxiliary energy window. Monte Carlo simulations were performed to carefully study aspects of bias and noise for the methods, and a torso phantom with cardiac insert was used to evaluate the performance of the methods for experimentally acquired data. The cross-talk compensation methods substantially improved lesion contrast and significantly reduced quantitative errors for simultaneously acquired data. Thallium image normalized mean square error (NMSE) was reduced from 0.522 without cross-talk compensation to as low as 0.052 with model-based cross-talk compensation. This is compared to a NMSE of 0.091 for the subtraction-based compensation method. The application of a preliminary model for crosstalk arising from lead fluorescence x-rays and collimator scatter gave promising results, and the future development of a more accurate model for collimator interactions would likely benefit simultaneous Tc/Tl imaging. Model-based compensation methods provide feasible cross-talk compensation in clinically acceptable times, and they may ultimately make simultaneous dual-isotope protocols an effective alternative for many imaging procedures. PMID:10442716

  15. 99mTc-3P-RGD2 SPECT to monitor early response to bevacizumab therapy in patients with advanced non-small cell lung cancer

    PubMed Central

    Chen, Bin; Zhao, Guoqing; Ma, Qingjie; Ji, Bin; Ji, Tiefeng; Xin, Hua; Gao, Shi

    2015-01-01

    The present study assessed the predictive value of 99mTc-3(poly-(ethylene glycol), PEG) 4-arginine-glycine-aspartic (99mTc-3P-RGD2) single photon emission computed tomography (SPECT) for the early identification of response to antiangiogenic treatment with bevacizumab in patients with advanced non-small cell lung cancer (NSCLC). Patients with advanced NSCLC treated with bevacizumab were prospectively studied with 99mTc-3P-RGD2 SPECT before and after 2 weeks from start of treatment. The tumor response was evaluated with RECIST criteria and related to observed change in the tumor to non-tumor (T/N) ratio for the largest known lesion. Receiver operating characteristic (ROC) curve analysis was used to determine T/N ratio changes with regard to predicting response to bevacizumab therapy. Change in T/N ratio was also related to progression-free survival (PFS) and overall survival (OS). Twenty-six patients were included, and 23 were finally assessable for metabolic response evaluation with 99mTc-3P-RGD2 SPECT. The cut-off value of T/N ratio change defined by ROC analysis was 24.4%. The sensitivity, specificity, and negative predictive value of 99mTc-3P-RGD2 SPECT for predicting tumor response were 81.8%, 91.7%, and 84.6%, respectively. Using the cut-off value defined by ROC analysis on 99mTc-3P-RGD2 SPECT, metabolic non-progressive disease patients (mNP) showed prolonged PFS (5.6 months versus 3.4 months; P < 0.001) and OS (17.1 months versus 8.6 months; P < 0.001) than metabolic progressive disease patients (mP). 99mTc-3P-RGD2 SPECT scan is a promising test to predict tumor response in patients with advanced non-small cell lung cancer early in the course of bevacizumab therapy. PMID:26884883

  16. Bombesin receptors and transplanted stem cells in rat brain: High-resolution scan with 99mTc BN1.1

    NASA Astrophysics Data System (ADS)

    Scopinaro, F.; Paschali, E.; Di Santo, G.; Antonellis, T.; Massari, R.; Trotta, C.; Gourni, H.; Bouziotis, P.; David, V.; Soluri, A.; Varvarigou, A. D.

    2006-12-01

    The aim of this work is to detect the presence of transplanted stem cells (TSC) in rat brain with high-resolution (HR) scintigraphy and labelled bombesin (BN). BN is a morphogen for Central Nervous System (CNS) as well as for other organs: CNS-oriented TSC over-express BN Receptors (BNR). BN is also a neurotransmitter and modulates several functions of CNS. 99mTc labelled BN-like peptide scan of CNS is the ideal method to detect growing TSC once knowing normal distribution of BNRs in CNS. HR Planar and single photon emission computerized tomography (SPECT) images of rat brain were performed with new HR detectors (Li-tech, Italy). Pertechnetate, 99mTc HMPAO and the new 99mTc BN1.1 (patented) were i.v. administered in five rats. HR SPECT of 99mTc BN1.1 detected olfactory tract, fronto-lateral cortex, cerebellum, basal ganglia and amygdale. Results of SPECT were confirmed by bio-distribution study performed after autopsy of three of the five rats. The remaining two rats underwent cerebral lesions followed by transplant of TSC. Three months later, HR scintigraphy was repeated and showed images completely different from previous basal study, with hot spot of 99mTc BN1.1 corresponding to the site of TSC transplant. Immuno-histochemistry confirmed the presence of viable TSC. Not only 99mTc BN1.1 HR scan showed viability of transplanted TSC but also the "background brain" was the still now unknown map of BNR in mammalian brain.

  17. [Usefulness of 201Tl/123I-BMIPP myocardial SPECT to evaluate myocardial viability and area at risk in acute myocardial infarction--comparison with 201Tl/99mTc-PYP dual SPECT].

    PubMed

    Isobe, N; Toyama, T; Hoshizaki, H; Oshima, S; Taniguchi, K

    1997-04-01

    To evaluate the area at risk and the myocardial viability of acute myocardial infarction (AMI), we compared rest 123I-beta-methyl iodophenyl pentadecanoic acid (123I-BMIPP) and 201Tl myocardial SPECT with 201Tl/99mTc-PYP dual SPECT (D-SPECT) in 65 patients (mean age 64 +/- 11 years) with AMI. D-SPECT was performed in 3 to 5 days, 123I-BMIPP myocardial SPECT in 5 to 7 days, and left ventriculography on 1 month after onset of AMI. Furthermore, 201Tl/123I-BMIPP myocardial SPECT and left ventriculography were performed on 4 months after onset of AMI. The area which showed the reduced 123I-BMIPP uptake was larger than that showed the accumulation of 99mTc-PYP. The improvement of regional wall motion on 4 months after onset of AMI tended to be more closely correlated with the existence of discrepancy zone between 201Tl and 123I-BMIPP uptake than that of overlap zone between 201Tl and 99mTc-PYP uptake in acute period. We conclude that 201Tl/123I-BMIPP myocardial SPECT is more useful to evaluate the area at risk and myocardial viability of AMI than D-SPECT. PMID:9183144

  18. Model-based correction for scatter and tailing effects in simultaneous 99mTc and 123I imaging for a CdZnTe cardiac SPECT camera.

    PubMed

    Holstensson, M; Erlandsson, K; Poludniowski, G; Ben-Haim, S; Hutton, B F

    2015-04-21

    An advantage of semiconductor-based dedicated cardiac single photon emission computed tomography (SPECT) cameras when compared to conventional Anger cameras is superior energy resolution. This provides the potential for improved separation of the photopeaks in dual radionuclide imaging, such as combined use of (99m)Tc and (123)I . There is, however, the added complexity of tailing effects in the detectors that must be accounted for. In this paper we present a model-based correction algorithm which extracts the useful primary counts of (99m)Tc and (123)I from projection data. Equations describing the in-patient scatter and tailing effects in the detectors are iteratively solved for both radionuclides simultaneously using a maximum a posteriori probability algorithm with one-step-late evaluation. Energy window-dependent parameters for the equations describing in-patient scatter are estimated using Monte Carlo simulations. Parameters for the equations describing tailing effects are estimated using virtually scatter-free experimental measurements on a dedicated cardiac SPECT camera with CdZnTe-detectors. When applied to a phantom study with both (99m)Tc and (123)I, results show that the estimated spatial distribution of events from (99m)Tc in the (99m)Tc photopeak energy window is very similar to that measured in a single (99m)Tc phantom study. The extracted images of primary events display increased cold lesion contrasts for both (99m)Tc and (123)I. PMID:25803643

  19. 99mTc-MDP bone SPECT for the evaluation of sternal ischaemia following internal mammary artery dissection.

    PubMed

    Lorberboym, M; Medalion, B; Bder, O; Lockman, J; Cohen, N; Schachner, A; Cohen, A J

    2002-01-01

    Coronary artery bypass grafting (CABG) is one of the most frequently performed operations in the United States. The use of internal mammary artery (IMA) grafting has been identified as increasing the risk of sternal wound infections and mediastinitis. The purpose of our study was to prospectively evaluate the effect of different techniques of left internal mammary artery (LIMA) harvesting on sternal vascularity. Thirty-three patients undergoing primary coronary artery bypass grafting were studied. The patients were divided into groups that received a skeletonized IMA (group I, n=11), a pedicled IMA (group II, n=12), or a semiskeletonized IMA (group III, n=10) graft. Each patient underwent a preoperative 99mTc-methylene diphosphonate bone scan using single photon emission computed tomography (SPECT). The ratio of the mean counts/pixel for each side of the sternum was obtained. Post-operatively, all patients had a repeat bone SPECT. Ratios of unilateral sternal uptakes were compared to the preoperative study. A univariable analysis of post-operative to pre-operative ratios revealed statistically significant reduction in vascularity to the left side of the sternum post-operatively in group II compared with groups I and III (0.68 0.12 vs 0.99 0.24 and 0.93 0.09; P<0.01). There was no difference between groups I and III (P=1). Multivariable analysis revealed only the type of harvesting to be associated with post-operative reduction in left to right sternal activity ratio (P<0.02). Pairwise comparisons revealed that differences are due to pedicled type of harvesting (group II vs group I, P=0.03; II vs III, P=0.001; and I vs III, P=0.115). A pedicled IMA graft causes acute post-operative sternal ischaemia. This does not occur when the IMA is skeletonized or semiskeletonized. Hence, it may be prudent to minimize dissection during mobilization of the IMA to decrease the likelihood of post-operative sternal complications. PMID:11748437

  20. Correlation between clinical severity of central nervous system (CNS) lupus and findings on single photon emission computed tomographic (SPECT) images of the brain; preliminary results

    SciTech Connect

    Silverman, I.E.; Zeit, R.M.; Von Feldt, J.M.

    1994-05-01

    Systemic Lupus Erythematosis (SLE) commonly causes significant neuropsychiatric disorders. The purpose of this study was to review the brain SPECT studies of SLE patients with clinical evidence of CNS involvement and determine whether there is a correlation between the findings on SPECT images and the clinical manifestations of this serious phase of the disease. We enrolled 19 SLE patients and 12 normal controls in this study. The level of each patient`s disease activity was determined by the SLE Disease Activity Index (SLEDAI), an established method of scoring disease severity which is heavily weighted toward neuropsychiatric symptomatology, for 15 of the 19 SLE patients. The SLEDAI was calculated within a 10 day window of the date when the SPECT scan was obtained. SPECT scans were performed 30 minutes following the intravenous administration of 99mTc-HMPAO. Results are discussed.

  1. Use of the cavity-to-myocardial count ratio with Tc-99m sestamibi myocardial perfusion SPECT to predict reduced left ventricular function

    SciTech Connect

    Heerden, B.B. van; Heerden, P.D.R. van; Wasserman, H.J.

    1994-05-01

    In patients with left ventricular dysfunction, the left ventricular cavity appears abnormally photopenic on SPECT images, both with T1-201 and Tc-99m sestamibi showed a linear correlation between the cavity-to-myocardial count ratio (C/M ratio) and left ventricular ejection fraction (LVEF) with T1-201 SPECT. Using an exercise ratio of 0.4 as the lower limit of normal, they could predict a reduced LVEF with a sensitivity of 83% and specificity of 78%. The purpose of our study was to ascertain whether the C/M ratio could also be used as an indicator of LVEF when using Tc-99m sestamibi as imaging agent.

  2. Technetium-99m bis (aminoethanethiol) complexes with amine sidechains--potential brain perfusion imaging agents for SPECT

    SciTech Connect

    Efange, S.M.; Kung, H.F.; Billings, J.; Guo, Y.Z.; Blau, M.

    1987-06-01

    In an effort to develop new clinically useful technetium-99m bis(aminoethanethiol) ((/sup 99m/Tc)BAT) complexes for the evaluation of regional cerebral perfusion, two new BAT ligands containing amines in the sidechain were synthesized and subsequently complexed with /sup 99m/Tc to yield the target complexes: (/sup 99m/Tc)DEA and (/sup 99m/Tc)TMPDA. Each complex was obtained as mixtures of two isomers, syn and anti, which were separated chromatographically. In biodistribution studies, both isomers of (/sup 99m/Tc)TMPDA showed little uptake in the brain. In contrast, the brain uptake values at 2 and 15 min for (/sup 99m/Tc)DEA-anti were 0.99 and 0.26, whereas, the corresponding values for DEA-syn were 2.27, 0.64% dose/organ, respectively. Autoradiographic studies (in rats) using both isomers of (/sup 99m/Tc)DEA show a fixed regional distribution and a higher concentration of radioactivity in the gray matter relative to the white matter. Planar imaging using (/sup 99m/Tc)DEA-syn clearly demonstrates localization of the complex in the brain with a T 1/2 of 41 min, suggesting some potential for use with single photon emission computed tomography.

  3. Evaluation of simultaneous 201Tl/99mTc dual-isotope cardiac SPECT imaging with model-based crosstalk compensation using canine studies

    PubMed Central

    Du, Y.; Links, J. M.; Becker, L.; DiPaula, A. F.; Frank, T.; Schuleri, K. H.; Lardo, A. C.; Frey, E. C.

    2014-01-01

    Background Simultaneous 201Tl/99mTc-Sestamibi dual-isotope myocardial perfusion SPECT imaging can reduce imaging time and produce perfectly registered rest/stress images. However, crosstalk from 99mTc into 201Tl images can significantly reduce 201Tl image quality. We have developed a model-based compensation (MBC) method to compensate for this crosstalk. The method has previously been validated with phantom and simulation studies. In this study, we evaluated the MBC method using a canine model. Methods Left anterior descending or left circumflex coronary artery stenoses were created in 50 adult mongrel dogs weighing 20–30 kg. The dogs were injected with 111 MBq (3 mCi) of 201Tl at rest, and a SPECT study acquired. Stress was induced by administering adenosine to the dog, followed by injection of 740 MBq (20 mCi) of 99mTc-Sestamibi at peak stress. A second SPECT study was performed with data acquired in both 201Tl and 99mTc energy windows to provide simultaneous dual-isotope projection data. The images were reconstructed using the ordered subsets-expectation maximization (OS-EM) reconstruction algorithm with compensation for attenuation, scatter and detector response. For simultaneously acquired 201Tl data, we also applied the MBC method to compensate for crosstalk contamination from 99mTc. Results Without compensation, 99mTc crosstalk increased the estimated 201Tl activity concentration in the rest images and reduced defect contrast. After MBC, the 201Tl images were in good agreement with the registered single isotope images and ex vivo count data. The ischemic (IS) to non-ischemic (NIS) region 201Tl activity concentration ratios were computed for single isotope and dual isotope studies. The correlation with ex vivo IS-NIS ratios was 0.815 after MBC, compared to the 0.495 from data without compensation. In addition, the regression line for the IS-NIS ratios with MBC was almost parallel to the line of identity with a slope of 0.93, compared to a slope of 0

  4. (99m)Tc-Labeled Multifunctional Low-Generation Dendrimer-Entrapped Gold Nanoparticles for Targeted SPECT/CT Dual-Mode Imaging of Tumors.

    PubMed

    Li, Xin; Xiong, Zuogang; Xu, Xiaoying; Luo, Yu; Peng, Chen; Shen, Mingwu; Shi, Xiangyang

    2016-08-10

    Development of cost-effective and highly efficient nanoprobes for targeted tumor single-photon emission computed tomography (SPECT)/computed tomography (CT) dual-mode imaging remains a challenging task. Here, multifunctional dendrimer-entrapped gold nanoparticles (Au DENPs) modified with folic acid (FA) and labeled with (99m)Tc were synthesized for targeted dual-mode SPECT/CT imaging of tumors. Generation 2 (G2) poly(amidoamine) (PAMAM) dendrimers (G2-NH2) conjugated with cyclic diethylenetriamine pentaacetic anhydride (cDTPAA) via an amide linkage and FA via a spacer of polyethylene glycol (PEG) were used for templated synthesis of Au core NPs, followed by labeling of (99m)Tc via chelation. The thus created multifunctional Au DENPs were well-characterized. It is shown that particles with an average Au core diameter of 1.6 nm can be dispersed in water, display stability under different conditions, and are cytocompatible in the studied concentration range. Further results demonstrate that the multifunctional nanoprobe is able to be utilized for targeted SPECT/CT dual-mode imaging of cancer cells having FA receptor (FAR)-overexpression in vitro and the established subcutaneous tumor model in vivo within a time frame up to 4 h. The formed multifunctional Au DENPs synthesized using dendrimers of low-generation may be employed as an effective and economic nanoprobe for SPECT/CT imaging of different types of FAR-expressing tumors. PMID:27434031

  5. Complete improvement in a patient with multiple irreversible defects of the left ventricle on 99m technetium-sestamibi SPECT after percutaneous coronary intervention.

    PubMed

    Javadi, H; Porpiranfar, M A; Semnani, S; Jallalat, S; Yavari, P; Mogharrabi, M; Hooman, A; Amini, A; Barekat, M; Iranpour, D; Assadi, M; Asli, I N

    2012-10-01

    99mTc-sestamibi has been investigated as a potential viability marker; initial studies have shown good concordance between 201Tl and 99mTc-sestamibi activities in both viable and nonviable myocardium. However, assessment of myocardial viability by 99mTc-sestamibi remains controversial for tissue recovery after revascularization. Here, we present a patient with several regions of severely diminished and irreversible (defect persisting in both early and delay images of each set scanning) defects on initial scan which were dissolved completely on the follow up scan after an intervention. In a 75 year-old Asian woman with acute myocardial infarction who received thrombolytic therapy and subjected to percutaneous coronary angiography (PCI) on day 28 after acute myocardial infarction(MI), resting 99mTc-sestamibi SPECT was applied on day 4 (initial scan) and 138 (follow up scan) after acute MI at 30 and 180 min after injection of tracer (740 MBq); Two-dimensional echocardiography was carried out at the same time. On the initial image set, there was irreversible defects in the apex, anteroapical, inferoapical, anteroseptal, septal and also anterior walls, while the follow up image was normal in all regions.The angiography intervention showed just significant stenosis on left anterior descending (LAD) vessel (95%). This may highlight the failure of 99mTc-sestamibi as a marker of myocardial viability and also mandate further validating of the procedure with follow up scan or other modalities for myocardial viability investigation. PMID:23090825

  6. Technetium-99m-d, 1-HM-PAO: a new radiopharmaceutical for imaging regional brain perfusion using SPECT--a comparison with iodine-123 HIPDM

    SciTech Connect

    Leonard, J.P.; Nowotnik, D.P.; Neirinckx, R.D.

    1986-12-01

    A new radiopharmaceutical, technetium-99m hexamethylpropyleneamine oxime (/sup 99m/Tc-d, 1-HM-PAO), has been reported to cross the blood-brain-barrier and to distribute in brain in proportion to regional blood flow. This study reports brain imaging obtained with /sup 99m/Tc-d,1 HM-PAO in 20 subjects; seven without evidence of cerebral disease and 13 with cerebrovascular disorders. In 16 patients comparative data were available with N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3-propanediamine ((/sup 123/I)HIPDM). Technetium-99m-d, 1-HM-PAO is retained sufficiently long to allow single photon emission computed tomography (SPECT) with widely available rotating gamma camera systems. The kinetics demonstrated a rapid brain uptake and prolonged retention of activity in cerebral structures. Good tomographic images are obtained with much higher uptake in gray than in white matter. Blood flow maps are comparable to those achieved with (/sup 123/I)HIPDM and established strokes were clearly seen, with similar details as in HIPDM studies. Delayed studies showed that the distribution in the brain remained virtually unchanged. Technetium-99m-d, 1-HM-PAO imaging appears particularly promising in routine examination of patients with cerebrovascular disorders.

  7. SPECT with (/sup 99m/Tc)-d,l-hexamethyl-propylene amine oxime (HM-PAO) compared with regional cerebral blood flow measured by PET: effects of linearization

    SciTech Connect

    Yonekura, Y.; Nishizawa, S.; Mukai, T.; Fujita, T.; Fukuyama, H.; Ishikawa, M.; Kikuchi, H.; Konishi, J.; Andersen, A.R.; Lassen, N.A.

    1988-12-01

    In order to validate the use of technetium-99m-d,l-hexamethylpropyleneamine oxime (HM-PAO) as a flow tracer, a total of 21 cases were studied with single photon emission computerized tomography (SPECT), and compared to regional cerebral blood flow (rCBF) measured by position emission tomography (PET) using the oxygen-15 CO2 inhalation technique. Although HM-PAO SPECT and rCBF PET images showed a similar distribution pattern the HM-PAO SPECT image showed less contrast between high and low activity flow regions than the rCBF image and a nonlinear relationship between HM-PAO activity and rCBF was shown. Based on the assumption of flow-dependent backdiffusion of HM-PAO from the brain, we applied a linearization algorithm to correct the HM-PAO SPECT images. The corrected HM-PAO SPECT images revealed a good linear correlation with rCBF (r = 0.901, p less than 0.001). The results indicated HM-PAO can be used as a flow tracer with SPECT after proper correction.

  8. SPECT brain imaging of the dopaminergic system in Parkinsonism using {sup 123}I and {sup 99m}Tc labeled agents

    SciTech Connect

    Du Yong

    2004-12-01

    SPECT brain imaging of the dopaminergic system using {sup 123}I and {sup 99m}Tc labeled agents, especially the simultaneous imaging of both pre- and postsynaptic neurons, promises to provide accurate diagnosis and differentiation of Parkinsonism. However, there are many degrading factors that affect the quality and quantitative accuracy of the SPECT images. These degrading factors limit the potential clinical applications of brain SPECT imaging. In this work, we studied these degrading factors by developing and validating a Monte Carlo (MC) method that provides accurate SPECT simulation with detailed modeling of the photon interactions inside the collimator detector system. To compensate for the partial volume effect (PVE) in the SPECT images caused by finite spatial resolution, we developed a new PVE compensation method that takes into account the effects of nonlinearity in iterative reconstruction-based compensation for image degrading factors, including attenuation, scatter, and collimator detector response. Compensation using the new method greatly improved the quantitative accuracy of brain SPECT images. We have also developed model-based method that can accurately estimate the downscatter and crosstalk contamination in the {sup 123}I imaging and the simultaneous {sup 123}I/{sup 99m}Tc dual-isotope imaging. Based on the model-based method, two different approaches to model-based downscatter and crosstalk contamination compensation were proposed. Both methods are based on iterative reconstruction and include compensation for other imaging degrading factors. The model-based downscatter and crosstalk compensation method provided greatly improved accuracy of activity estimates with little effect on the precision. Finally, optimization of energy windows for simultaneous {sup 123}I/{sup 99m}Tc acquisition was performed to find the energy windows with the best trade-off between minimizing the crosstalk and maximizing the detection efficiency for simultaneous

  9. Comparison of myocardial contrast echocardiography with NC100100 and 99mTc sestamibi SPECT for detection of resting myocardial perfusion abnormalities in patients with previous myocardial infarction

    PubMed Central

    Jucquois, I; Nihoyannopoulos, P; D'Hondt, A; Roelants, V; Robert, A; Melin, J; Glass, D; Vanoverschelde, J

    2000-01-01

    OBJECTIVE—To determine whether myocardial contrast echocardiography (MCE) following intravenous injection of perfluorocarbon microbubbles permits identification of resting myocardial perfusion abnormalities in patients who have had a previous myocardial infarction.
PATIENTS AND INTERVENTIONS—22 patients (mean (SD) age 66 (11) years) underwent MCE after intravenous injection of NC100100, a novel perfluorocarbon containing contrast agent, and resting 99mTc sestamibi single photon emission computed tomography (SPECT). With both methods, myocardial perfusion was graded semiquantitatively as 1 = normal, 0.5 = mild defect, and 0 = severe defect.
RESULTS—Among the 203 normally contracting segments, 151 (74%) were normally perfused by SPECT and 145 (71%) by MCE. With SPECT, abnormal tracer uptake was mainly found among normally contracting segments from the inferior wall. By contrast, with MCE poor myocardial opacification was noted essentially among the normally contracting segments from the anterior and lateral walls. Of the 142 dysfunctional segments, 87 (61%) showed perfusion defects by SPECT, and 94 (66%) by MCE. With both methods, perfusion abnormalities were seen more frequently among akinetic than hypokinetic segments. MCE correctly identified 81/139 segments that exhibited a perfusion defect by SPECT (58%), and 135/206 segments that were normally perfused by SPECT (66%). Exclusion of segments with attenuation artefacts (defined as abnormal myocardial opacification or sestamibi uptake but normal contraction) by either MCE or SPECT improved both the sensitivity (76%) and the specificity (83%) of the detection of SPECT perfusion defects by MCE.
CONCLUSIONS—The data suggest that MCE allows identification of myocardial perfusion abnormalities in patients who have had a previous myocardial infarction, provided that regional wall motion is simultaneously taken into account.


Keywords: myocardial contrast echocardiography; NC100100

  10. Radiation exposure of the investigator's hand during fusion imaging of the thyroid with 99mTcO4-free-hand SPECT and ultrasound.

    PubMed

    Freesmeyer, Martin; Winkens, Thomas; Opfermann, Thomas; Kühnel, Christian

    2016-03-01

    The objective of this study was to assess the radiation exposure of the investigators' hand during free-hand single photon emission tomography/ultrasound ((99m)TcO4-fhSPECT/US) of the thyroid. Conventional dosimetry by rings with thermoluminescent detectors (TLDs) was performed in 32 patients (Group A), followed by TLD-chipstrate dosimetry in further 20 patients (Group B). In both the groups, the ambient dose rate was measured by dose rate meter (DRM). The applied activity was in the range of 60-80 MBq (99m)TcO4. In Group A, the exposure per investigation was 7.53 µSv (calculated average) by ring dosimetry and 9.02±5.64 µSv by DRM; in Group B, 10.93 and 9.51 ± 1.76 µSv, respectively. Based on estimated 1224 yearly thyroid investigations per nuclear medicine specialist in Germany, the estimated cumulative yearly exposure of the hand was 11.32 mSv. The hand exposure during a thyroid (99m)TcO4-fhSPECT/US of 20-min duration proved modest and comparable with different methods. Yearly examinations in excess of 1000 per investigator are not expected to add a relevant cumulative risk. PMID:26231559

  11. (99m)Tc(N)-DBODC(5), a potential radiolabeled probe for SPECT of multidrug resistance: in vitro study.

    PubMed

    Bolzati, Cristina; Carta, Davide; Gandin, Valentina; Marzano, Cristina; Morellato, Nicolò; Salvarese, Nicola; Cantore, Mariangela; Colabufo, Nicola Antonio

    2013-06-01

    [(99m)Tc(N)(DBODC)(PNP5)](+) [DBODC is bis(N-ethoxyethyl)dithiocarbamato; PNP5 is bis(dimethoxypropylphosphinoethyl)ethoxyethylamine], abbreviated as (99m)Tc(N)-DBODC(5), is a lipophilic cationic mixed compound investigated as a myocardial imaging agent. The findings that this tracer accumulates in mitochondrial structures through a mechanism mediated by the negative mitochondrial membrane potential and that the rapid efflux of (99m)Tc(N)-DBODC(5) from nontarget tissues seems to be associated with the multidrug resistance (MDR) P-glycoprotein (P-gp) transport function open up the possibility to extend its clinical applications to tumor imaging and noninvasive MDR studies. The rate of uptake at 4 and 37 °C of (99m)Tc(N)-DBODC(5) was evaluated in vitro in selected human cancer cell lines and in the corresponding sublines before and after P-gp and/or MDR-associated protein (MRP) modulator/inhibitor treatment using (99m)Tc-sestamibi as a reference. The results indicated that (1) the uptake of both (99m)Tc(N)-DBODC(5) and (99m)Tc-sestamibi is correlated to metabolic activity of the cells and (2) the cellular accumulation is connected to the level of P-gp/MRP expression; in fact, an enhancement of uptake in resistant cells was observed after treatment with opportune MDR inhibitor/modulator, indicating that the selective blockade of P-gp/MRP prevented efflux of the tracers. This study provides a preliminary indication of the applicability of (99m)Tc(N)-DBODC(5) in tumor imaging and in detecting P-gp/MRP-mediated drug resistance in human cancer. In addition, the possibility to control the hydrophobicity and pharmacological activity of this heterocomplex through the variation of the substituents on the ligands backbone without affecting the P2S2 coordinating sphere makes (99m)Tc(N)-DBODC(5) a suitable scaffold for the preparation of a molecular probe for single photon emission computed tomography of MDR. PMID:23543234

  12. In vivo detection of small tumour lesions by multi-pinhole SPECT applying a 99mTc-labelled nanobody targeting the Epidermal Growth Factor Receptor

    PubMed Central

    Krüwel, Thomas; Nevoltris, Damien; Bode, Julia; Dullin, Christian; Baty, Daniel; Chames, Patrick; Alves, Frauke

    2016-01-01

    The detection of tumours in an early phase of tumour development in combination with the knowledge of expression of tumour markers such as epidermal growth factor receptor (EGFR) is an important prerequisite for clinical decisions. In this study we applied the anti-EGFR nanobody 99mTc-D10 for visualizing small tumour lesions with volumes below 100 mm3 by targeting EGFR in orthotopic human mammary MDA-MB-468 and MDA-MB-231 and subcutaneous human epidermoid A431 carcinoma mouse models. Use of nanobody 99mTc-D10 of a size as small as 15.5 kDa enables detection of tumours by single photon emission computed tomography (SPECT) imaging already 45 min post intravenous administration with high tumour uptake (>3% ID/g) in small MDA-MB-468 and A431 tumours, with tumour volumes of 52.5 mm3 ± 21.2 and 26.6 mm3 ± 16.7, respectively. Fast blood clearance with a serum half-life of 4.9 min resulted in high in vivo contrast and ex vivo tumour to blood and tissue ratios. In contrast, no accumulation of 99mTc-D10 in MDA-MB-231 tumours characterized by a very low expression of EGFR was observed. Here we present specific and high contrast in vivo visualization of small human tumours overexpressing EGFR by preclinical multi-pinhole SPECT shortly after administration of anti-EGFR nanobody 99mTc-D10. PMID:26912069

  13. In vivo detection of small tumour lesions by multi-pinhole SPECT applying a (99m)Tc-labelled nanobody targeting the Epidermal Growth Factor Receptor.

    PubMed

    Krüwel, Thomas; Nevoltris, Damien; Bode, Julia; Dullin, Christian; Baty, Daniel; Chames, Patrick; Alves, Frauke

    2016-01-01

    The detection of tumours in an early phase of tumour development in combination with the knowledge of expression of tumour markers such as epidermal growth factor receptor (EGFR) is an important prerequisite for clinical decisions. In this study we applied the anti-EGFR nanobody (99m)Tc-D10 for visualizing small tumour lesions with volumes below 100 mm(3) by targeting EGFR in orthotopic human mammary MDA-MB-468 and MDA-MB-231 and subcutaneous human epidermoid A431 carcinoma mouse models. Use of nanobody (99m)Tc-D10 of a size as small as 15.5 kDa enables detection of tumours by single photon emission computed tomography (SPECT) imaging already 45 min post intravenous administration with high tumour uptake (>3% ID/g) in small MDA-MB-468 and A431 tumours, with tumour volumes of 52.5 mm(3) ± 21.2 and 26.6 mm(3) ± 16.7, respectively. Fast blood clearance with a serum half-life of 4.9 min resulted in high in vivo contrast and ex vivo tumour to blood and tissue ratios. In contrast, no accumulation of (99m)Tc-D10 in MDA-MB-231 tumours characterized by a very low expression of EGFR was observed. Here we present specific and high contrast in vivo visualization of small human tumours overexpressing EGFR by preclinical multi-pinhole SPECT shortly after administration of anti-EGFR nanobody (99m)Tc-D10. PMID:26912069

  14. [The diagnostic value of Tc-99m PYP, Tl-201 dual isotope SPECT to predict the viability of damaged myocardium in the acute phase of myocardial infarction--comparison with stress, delayed, and reinjected Tl-201 SPECT].

    PubMed

    Matsuo, H; Watanabe, S; Arai, M; Kotoo, Y; Oohashi, H; Oda, H; Ueno, K; Matsubara, T; Ohno, M; Mori, S

    1991-05-01

    To assess the diagnostic value of Tc-99m PYP, Tl-201 dual isotope SPECT for the evaluation of myocardial viability, segmental comparison between dual isotope SPECT and exercise, delayed, and reinjected Tl study were performed with 18 AMI patients. Among 72 damaged myocardial segments, 48 segments (67%) were judged as viable by chronic phase Tl studies. The segments with severely reduced Tl uptake by dual SPECT showed significantly lower prevalence of viable myocardium than the segments with reduced and normal Tl uptake (p less than 0.001). The segments with PYP accumulation localized to the subendocardium represented the favorable outcome compared with the transmural accumulation (p less than 0.001). And overlap segments show better prognosis than the segments without overlap (p less than 0.05). Most importantly, we can get better predictive accuracy of myocardial scar by dual isotope SPECT than the judgement by Tl or PYP SPECT alone (83.3% vs 77.8%, 68.1%). Thus, we conclude that Tc-99m PYP, Tl-201 dual isotope SPECT is useful to assess the severity of myocardial damage in the acute phase of myocardial infarction. PMID:1653372

  15. Diagnosis of bone infection by complementary role of technetium-99m MDP and technetium-99m hexamethylpropylene-amineoxime-leukocytes

    PubMed Central

    Al-Zahrani, Abdullah; El-Saban, Khaled; Al-Sakhri, Hijji

    2012-01-01

    Purpose: Valuate complementary role of 99mTc-MDP bone scan and 99mTechnetium hexamethylpropylene-amineoxime (99mTc-HMPAO) labeled leukocyte scintigraphy in diagnosis of bone infection. Patients and Methods: Ninety one sites suspected to have bone infection were divided in to two groups: Group I 49 sites with current endo-prothesis; and group II 42 sites with no prosthesis. All patients were subjected to serial images of 99mTc-HMPAO labeled leukocyte (99mTc-white blood cells (WBCs)), triple phase bone scan (99mTc-MDP) and plain X-ray, in addition to clinical and bacteriological assessment, together with follow-up. Results: The overall sensitivity (Sn) was found to be 34.9%, 95.4%, and 86% for plain X-ray, 99mTc-MDP, and 99mTc-WBCs respectively. Concerning specificity (Sp) was found to be 47.9%, 45.8%, and 91.7% respectively for the three imaging modalities. 99mTc-WBCs showed better Sn, Sp, and accuracy in group I (95%, 93.1% and 93.9%, respectively) compared to 40%, 41.4%, and 40.8% for plain X-ray and 90%, 62%, and 73.5% respectively for 99mTc-MDP. On the other hand, 99mTc-MDP proved to have best Sn 100% versus 78.3% and 30.4% for 99mTc-WBCs and plain X-ray respectively. Yet, Sp and accuracy was found to best for 99mTc-WBCs (89.5% and 83.3% respectively) compared to 57.9% and 42.9% for plain X-ray and 21.1% and 64.3% for 99mTc-MDP. Conclusion: Combined imaging with 99mTc-WBCs and 99mTc-MDP proved to be effective in early detection of bone infection in the presence or absence of prosthesis. PMID:23919069

  16. [Verbal auditory agnosia: SPECT study of the brain].

    PubMed

    Carmona, C; Casado, I; Fernández-Rojas, J; Garín, J; Rayo, J I

    1995-01-01

    Verbal auditory agnosia are rare in clinical practice. Clinically, it characterized by impairment of comprehension and repetition of speech but reading, writing, and spontaneous speech are preserved. So it is distinguished from generalized auditory agnosia by the preserved ability to recognize non verbal sounds. We present the clinical picture of a forty-years-old, right handed woman who developed verbal auditory agnosic after an bilateral temporal ischemic infarcts due to atrial fibrillation by dilated cardiomyopathie. Neurophysiological studies by pure tone threshold audiometry: brainstem auditory evoked potentials and cortical auditory evoked potentials showed sparing of peripheral hearing and intact auditory pathway in brainstem but impaired cortical responses. Cranial CT-SCAN revealed two large hypodenses area involving both cortico-subcortical temporal lobes. Cerebral SPECT using 99mTc-HMPAO as radiotracer showed hypoperfusion just posterior in both frontal lobes nect to Roland's fissure and at level of bitemporal lobes just anterior to Sylvian's fissure. PMID:8556589

  17. [Clinical evaluation of patients with right ventricular infarction detected by dual SPECT imaging of thallium-201 and technetium-99m pyrophosphate].

    PubMed

    Kuwano, H; Kimura, M; Sakai, K; Ishiguro, J; Ishida, H; Okabe, M

    1994-10-01

    We evaluated clinical significance of dual-nuclide SPECT imaging (D-SPECT) of thallium-201 and technetium-99m pyrophosphate (PYP) in patients of acute inferior left ventricular infarction with PYP uptake in the right ventricle (PYP (+) group) in comparison with those without PYP uptake (PYP (-) group). There was no difference in coronary risk factors, history of angina, blood pressure, heart rate, and hemodynamics on admission between PYP (+) group and PYP (-) group. The duration from onset to admission was longer in PYP (+) group and coronary reperfusion therapies were carried out in few cases. In 7 of 8 PYP-positive patients, the diagnosis of right ventricular infarction was made only by D-SPECT. Four of 8 were complicated with shock within three days, and the duration of hospitalization was longer. Coronary angiography demonstrated many proximal lesions (50%) in PYP (+) group but few ones (18%) in PYP (-) group. D-SPECT was very useful for diagnosing acute right ventricular infarction, and it might contribute to the prevention of shock if performed within a few days. PMID:7807721

  18. SPECT Imaging of Mice with 99mTc-Radiopharmaceuticals Obtained from 99Mo Produced by 100Mo(n,2n)99Mo and Fission of 235U

    NASA Astrophysics Data System (ADS)

    Hashimoto, Kazuyuki; Nagai, Yasuki; Kawabata, Masako; Sato, Nozomi; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji; Ohta, Masayuki; Konno, Chikara; Ochiai, Kentaro; Kawauchi, Yukimasa; Ohta, Akio; Shiina, Takayuki; Takeuchi, Nobuhiro; Ashino, Hiroki; Nakahara, Yuto

    2015-04-01

    The distribution of 99mTc-radiopharmaceutical in mouse was determined by single photon emission computed tomography (SPECT) for the first time using 99mTc, which was separated by thermochromatography from 99Mo produced via the 100Mo(n,2n)99Mo reaction with accelerator neutrons. The SPECT image was comparable to that obtained using the fission product 99Mo. Radionuclidic and radiochemical purities of the separated 99mTc and its aluminum concentration met the United States Pharmacopeia regulatory requirements for 99mTc from the fission product 99Mo. These results provide important evidence that the 99mTc-radiopharmaceutical formulated using the (n,2n) 99Mo can be a promising substitute for the fission product 99Mo. The current and forthcoming problem of ensuring a reliable and constant supply of 99Mo in Japan can be partially mitigated.

  19. Predictive Models for Regional Hepatic Function Based upon 99mTc-IDA SPECT and Local Radiation Dose for Physiological Adaptive RT

    PubMed Central

    Wang, Hesheng; Feng, Mary; Frey, Kirk A.; Ten Haken, Randall K.; Lawrence, Theodore S.; Cao, Yue

    2013-01-01

    Purpose High dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed prior to and during the course of RT using 99mTc-labeled immindodiacetic acid (IDA) SPECT could predict regional liver function reserve after RT. Methods and Materials Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans prior to RT, during, and one month after completion of RT. Indocyanine green (ICG) tests (a measure of overall liver function) were performed within 1 day of each scan. 3D volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After co-registration of the CT/SPECT and the treatment planning CT, HEF dose-response functions during and post-RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, Dose, Priori and Adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function post-RT. Results The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r = −0.80, p<0.0001), for all time points. Linear correlations between local doses and regional HEFs one month post-RT were significant in 12 patients. In the priori model, regional HEF post-RT was predicted by the planned dose and regional HEF assessed prior to RT (R=0.71, p<0.0001). In the adaptive model, regional HEF post-RT was predicted by regional HEF re-assessed during RT and the remaining planned local dose (R=0.83, p<0.0001). Conclusions 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of

  20. A new dual-isotope convolution cross-talk correction method: a Tl-201/Tc-99m SPECT cardiac phantom study.

    PubMed

    Knesaurek, K

    1994-10-01

    Simultaneous dual-isotope SPECT imaging provides a clear advantage in situations where two concurrent metabolic, anatomic, or background measurements are desired. It obviates the need for two separate imaging sessions, reduces patient motion problems, and provides exact image registration between images. However, a potential limitation of dual-isotope SPECT imaging is contribution of scattered and primary photons from one radionuclide into the second radionuclide's photopeak energy window, referred to here as cross-talk. Cross-talk in both photopeak energy windows can significantly degrade image quality, resolution, and quantitation to an unacceptable level. Simple cross-talk correction method used in dual-radionuclide in vitro counting, even applied on a pixel-by-pixel basis, does not account for the differences in spatial distribution of the photopeak and cross-talk photons. Here a new convolution cross-talk correction method is presented. The convolution filters are derived from point response functions (PRFs) for Tc-99m and Tl-201 point sources. Three separate acquisitions were performed, each with two 20% wide energy windows, one centered at 140 keV and another at 70 keV. The first acquisition was done with Tc-99m solution only, the second with Tl-201 solution only, and the third with a mixture of Tc-99m and Tl-201. The nonuniform RH-2 thorax-heart phantom was used to test a new correction technique. The main difficulty and limitation of the convolution correction approach is caused by the variation in PRF as a function of depth. Thus, average PRF should be used in the creation of an approximative filter.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7869989

  1. SPECT brain perfusion imaging with Tc-99m ECD: Semi-quantitative regional analysis and database mapping

    SciTech Connect

    Schiepers, C.; Hegge, J.; De Roo, M.

    1994-05-01

    Brain SPECT is a well accepted method for the assessment of brain perfusion in various disorders such as epilepsy, stroke, dementia. A program for handling the tomographic data was developed, using a commercial spreadsheet (Microsoft EXCEL) with a set of macro`s for analysis, graphic display and database management of the final results.

  2. Gallbladder Activity on 99mTc-Labeled Red Cell Scintigraphy Confirmed by SPECT/CT Imaging.

    PubMed

    Wang, Ling; Jing, Hongli; Chen, Libo; Wang, Zhenghua; Li, Fang

    2016-09-01

    Tc-labeled red cell (Tc-RBC) scintigraphy is commonly used to detect gastrointestinal bleeding. Gallbladder visualization on Tc-RBC scintigraphy is not common. We present a case of gallbladder visualization on Tc-RBC scintigraphy confirmed by SPECT/CT imaging in a patient with chronic renal failure and anemia. PMID:27405034

  3. SPECT imaging of Moyamoya disease using /sup 99m/Tc-HM-PAO. Comparison with computed tomography findings

    SciTech Connect

    Mountz, J.M.; Foster, N.L.; Ackermann, R.J.; Bluemlein, L.; Petry, N.A.; Kuhl, D.E.

    1988-10-01

    /sup 99m/Tc-HM-PAO was used to evaluate regional cerebral blood flow in a 26-year-old woman with Moyamoya disease. This patient had an 18-month history of recurrent neurologic deficits and had angiographic evidence of Moyamoya disease. She had used oral contraceptives and cigarettes, but had no other risk factors for stroke. Single photon emission computed tomographic images showed bilateral and asymmetric reductions in blood flow to anterior and lateral brain regions. These findings correlated better with clinical symptomatology and suggested more extensive brain involvement than did computed tomography.

  4. Initial In Vivo Quantification of Tc-99m Sestamibi Uptake as a Function of Tissue Type in Healthy Breasts Using Dedicated Breast SPECT-CT

    PubMed Central

    Mann, Steve D.; Perez, Kristy L.; McCracken, Emily K. E.; Shah, Jainil P.; Wong, Terence Z.; Tornai, Martin P.

    2012-01-01

    A pilot study is underway to quantify in vivo the uptake and distribution of Tc-99m Sestamibi in subjects without previous history of breast cancer using a dedicated SPECT-CT breast imaging system. Subjects undergoing diagnostic parathyroid imaging studies were consented and imaged as part of this IRB-approved breast imaging study. For each of the seven subjects, one randomly selected breast was imaged prone-pendant using the dedicated, compact breast SPECT-CT system underneath the shielded patient support. Iteratively reconstructed and attenuation and/or scatter corrected images were coregistered; CT images were segmented into glandular and fatty tissue by three different methods; the average concentration of Sestamibi was determined from the SPECT data using the CT-based segmentation and previously established quantification techniques. Very minor differences between the segmentation methods were observed, and the results indicate an average image-based in vivo Sestamibi concentration of 0.10 ± 0.16 μCi/mL with no preferential uptake by glandular or fatty tissues. PMID:22956950

  5. Optimization of the filter parameters in (99m)Tc myocardial perfusion SPECT studies: the formulation of flowchart.

    PubMed

    Shibutani, Takayuki; Onoguchi, Masahisa; Yamada, Tomoki; Kamida, Hiroki; Kunishita, Kohei; Hayashi, Yuuki; Nakajima, Tadashi; Kinuya, Seigo

    2016-06-01

    Myocardial perfusion single photon emission computed tomography (SPECT) is typically subject to a variation in image quality due to the use of different acquisition protocols, image reconstruction parameters and image display settings by each institution. One of the principal image reconstruction parameters is the Butterworth filter cut-off frequency, a parameter strongly affecting the quality of myocardial images. The objective of this study was to formulate a flowchart for the determination of the optimal parameters of the Butterworth filter for filtered back projection (FBP), ordered subset expectation maximization (OSEM) and collimator-detector response compensation OSEM (CDR-OSEM) methods using the evaluation system of the myocardial image based on technical grounds phantom. SPECT studies were acquired for seven simulated defects where the average counts of the normal myocardial components of 45° left anterior oblique projections were approximately 10-120 counts/pixel. These SPECT images were then reconstructed by FBP, OSEM and CDR-OSEM methods. Visual and quantitative assessment of short axis images were performed for the defect and normal parts. Finally, we formulated a flowchart indicating the optimal image processing procedure for SPECT images. Correlation between normal myocardial counts and the optimal cut-off frequency could be represented as a regression expression, which had high or medium coefficient of determination. We formulated the flowchart in order to optimize the image reconstruction parameters based on a comprehensive assessment, which enabled us to perform objectively processing. Furthermore, the usefulness of image reconstruction using the flowchart was demonstrated by a clinical case. PMID:27052439

  6. (99m)Tc-HisoDGR as a Potential SPECT Probe for Orthotopic Glioma Detection via Targeting of Integrin α5β1.

    PubMed

    Zhao, Haitao; Gao, Hannan; Zhai, Luoping; Liu, Xujie; Jia, Bing; Shi, Jiyun; Wang, Fan

    2016-05-18

    Integrins, a large family of cell adhesion receptors, have been shown to play an important role for glioma proliferation and invasion. Several integrin receptors, including αvβ3, αvβ5, and α5β1, have generated clinical interest for glioma diagnosis and antitumor therapy. Integrin α5β1 has been highlighted as a prognostic and diagnostic marker in glioma, and its expression is correlated with a worse prognosis in high-grade glioma. However, unlike extensively studied integrins αvβ3 and αvβ5, very few integrin α5β1-specific radiotracers have been reported. Developing α5β1-specific radiotracers may provide alternative diagnosis and evaluation options in addition to well-studied αvβ3/αvβ5-specific tracers, and they may add new documents for profiling tumor progression. Here, a novel integrin α5β1-specific probe (99m)Tc-HisoDGR was fabricated for SPECT (single-photon emission computed tomography) imaging of glioma. To confirm its selective targeting of integrin α5β1 in vivo, the mouse models of α5β1-positive U87MG human glioma were subjected to SPECT/CT scans, and biodistribution experiments and blocking studies were performed. Small-animal SPECT/CT imaging experiments demonstrated that the tumors were clearly visualized in both subcutaneous and orthotopic glioma tumor models with clear background at 0.5, 1, and 2 h p.i. The tumor accumulation of (99m)Tc-HisoDGR showed significant reduction when excess cold isoDGR peptide was coinjected, suggesting that the tumor uptake was specifically mediated. Our work revealed that (99m)Tc-HisoDGR represented a powerful molecular probe for integrin α5β1-positive cancer imaging; moreover, it might be a promising tool for evaluating malignancy, predicting prognosis, selecting subpopulations of patients who might be sensitive to integrin α5β1-targeted drugs, and assessing and monitoring the response to integrin α5β1-targeted drugs in clinical trials. PMID:27098436

  7. The Effect of Morphine on Regional Cerebral Blood Flow Measured by 99mTc-ECD SPECT in Dogs

    PubMed Central

    Adriaens, Antita; Peremans, Kathelijne; Waelbers, Tim; Vandermeulen, Eva; Croubels, Siska; Duchateau, Luc; Dobbeleir, André; Audenaert, Kurt; Eersels, Jos; Vermeire, Simon; De Spiegeleer, Bart; Polis, Ingeborgh

    2014-01-01

    To gain insights into the working mechanism of morphine, regional cerebral blood flow (rCBF) patterns after morphine administration were assessed in dogs. In a randomized cross-over experimental study, rCBF was estimated with 99mTc-Ethylcysteinate Dimer single photon emission computed tomography in 8 dogs at baseline, at 30 minutes and at 120 minutes after a single bolus of morphine. Perfusion indices (PI) in the frontal, parietal, temporal and occipital cortex and in the subcortical and cerebellar region were calculated. PI was significantly decreased 30 min after morphine compared to baseline in the right frontal cortex. The left parietal cortex and subcortical region showed a significantly increased PI 30 min after morphine compared to baseline. No significant differences were noted for the other regions or at other time points. In conclusion, a single bolus of morphine generated a changing rCBF pattern at different time points. PMID:25295733

  8. Pituitary Prolactinoma Imaged by 99mTc-Sestamibi SPECT/CT in a Multiple Endocrine Neoplasia Type 1 Patient.

    PubMed

    Pan, Yu; Lv, Jing; Guo, Rui; Pan, Mengyi; Zhang, Yifan

    2016-06-01

    A 35-year-old woman who had undergone bilateral inferior parathyroidectomy for primary hyperparathyroidism was referred to our hospital to evaluate the cause of irregular menses, galactorrhea, and paroxysmal headache. Multiple endocrine neoplasia type 1 was then suspected for the high levels of plasma prolactin, parathyroid hormone, serum calcium, insulin, and related symptoms. A Tc-sestamibi SPECT/CT acquired to evaluate parathyroid glands unexpectedly revealed an increased accumulation in the pituitary gland, which was further confirmed by enhanced magnetic resonance imaging as a pituitary microadenoma. Bromocriptine treatment gradually reduced the prolactin level. PMID:26828146

  9. Accurate Characterization of Skeletal Lesions in Tuberous Sclerosis Complex Using 99mTc MDP SPECT/CT.

    PubMed

    Parida, Girish Kumar; Dhull, Varun Singh; Karunanithi, Sellam; Arora, Saurabh; Sharma, Anshul; Shamim, Shamim Ahmed

    2015-09-01

    We report a 15-year-old patient with tuberous sclerosis complex or Bourneville's disease with history of generalized tonic-clonic seizure for last 2 years and was currently on antiepileptic medication. He also had a history of left nephrectomy for renal cell carcinoma clear cell type. The patient had multiple adenoma sebaceum over the nasolabial region, ash leaf spots over the lower limbs, a Shagreen patch over the back, and multiple calcified tubers in the subependymal region. He was then referred for the skeletal scintigraphy to look for skeletal lesions, which revealed involvement of bilateral humeri, tibiae, and iliac bones accurately characterized on SPECT/CT. PMID:26098284

  10. 99mTc-labelled anti-CD11b SPECT/CT imaging allows detection of plaque destabilization tightly linked to inflammation.

    PubMed

    Liu, Guobing; Hu, Yan; Xiao, Jie; Li, Xiao; Li, Yanli; Tan, Hui; Zhao, Yanzhao; Cheng, Dengfeng; Shi, Hongcheng

    2016-01-01

    It remains challenging to predict the risk of rupture for a specific atherosclerotic plaque timely, a thrombotic trigger tightly linked to inflammation. CD11b, is a biomarker abundant on inflammatory cells, not restricted to monocytes/macrophages. In this study, we fabricated a probe named as (99m)Tc-MAG3-anti-CD11b for detecting inflamed atherosclerotic plaques with single photon emission computed tomography/computed tomography (SPECT/CT). The ApoE-knockout (ApoE(-/-)) mice were selected to establish animal models, with C57BL/6J mice used for control. A higher CD11b(+)-cell recruitment with higher CD11b expression and more serious whole-body inflammatory status were identified in ApoE(-/-) mice. The probe showed high in vitro affinity and specificity to the Raw-264.7 macrophages, as well as inflammatory cells infiltrated in atherosclerotic plaques, either in ex vivo fluorescent imaging or in in vivo micro-SPECT/CT imaging, which were confirmed by ex vivo planar gamma imaging, Oil-Red-O staining and CD11b-immunohistochemistry staining. A significant positive relationship was identified between the radioactivity intensity on SPECT/CT images and the CD11b expression in plaques. In summary, this study demonstrates the feasibility of anti-CD11b antibody mediated noninvasive SPECT/CT imaging of inflammatory leukocytes in murine atherosclerotic plaques. This imaging strategy can identify inflammation-rich plaques at risk for rupture and evaluate the effectiveness of inflammation-targeted therapies in atheroma. PMID:26877097

  11. 99mTc-labelled anti-CD11b SPECT/CT imaging allows detection of plaque destabilization tightly linked to inflammation

    PubMed Central

    Liu, Guobing; Hu, Yan; Xiao, Jie; Li, Xiao; Li, Yanli; Tan, Hui; Zhao, Yanzhao; Cheng, Dengfeng; Shi, Hongcheng

    2016-01-01

    It remains challenging to predict the risk of rupture for a specific atherosclerotic plaque timely, a thrombotic trigger tightly linked to inflammation. CD11b, is a biomarker abundant on inflammatory cells, not restricted to monocytes/macrophages. In this study, we fabricated a probe named as 99mTc-MAG3-anti-CD11b for detecting inflamed atherosclerotic plaques with single photon emission computed tomography/computed tomography (SPECT/CT). The ApoE-knockout (ApoE−/−) mice were selected to establish animal models, with C57BL/6J mice used for control. A higher CD11b+-cell recruitment with higher CD11b expression and more serious whole-body inflammatory status were identified in ApoE−/− mice. The probe showed high in vitro affinity and specificity to the Raw-264.7 macrophages, as well as inflammatory cells infiltrated in atherosclerotic plaques, either in ex vivo fluorescent imaging or in in vivo micro-SPECT/CT imaging, which were confirmed by ex vivo planar gamma imaging, Oil-Red-O staining and CD11b-immunohistochemistry staining. A significant positive relationship was identified between the radioactivity intensity on SPECT/CT images and the CD11b expression in plaques. In summary, this study demonstrates the feasibility of anti-CD11b antibody mediated noninvasive SPECT/CT imaging of inflammatory leukocytes in murine atherosclerotic plaques. This imaging strategy can identify inflammation-rich plaques at risk for rupture and evaluate the effectiveness of inflammation-targeted therapies in atheroma. PMID:26877097

  12. Simultaneous 99mTc-MDP/123I-MIBG tumor imaging using SPECT-CT: Phantom and constructed patient studies

    PubMed Central

    Rakvongthai, Yothin; Fakhri, Georges El; Lim, Ruth; Bonab, Ali A.; Ouyang, Jinsong

    2013-01-01

    Purpose: Authors’ goal is to evaluate the performance of simultaneous 99mTc-MDP/123I-MIBG tumor imaging with fast Monte-Carlo (MC) based joint iterative reconstruction as compared to sequential 99mTc-MDP and 123I-MIBG tumor imaging. Methods: Noise-free 99mTc and 123I SPECT projections were acquired separately using an anthropomorphic torso phantom modified to include a fillable tube around the lungs to mimic ribs. Additionally, 99mTc and 123I projections were acquired separately using a 1-cm spherical “tumor” placed at various distances from one detector. Tumor-present data were generated by adding tumor projections to the torso phantom data, which were scaled to the total counts in typical clinical studies. Twenty-five noise realizations were generated by adding Poisson noise to the projection data for each radionuclide. Dual-radionuclide data were synthesized by summing the 99mTc and 123I projections. Image reconstruction was performed using: (1) SR-OSEM, ordered subset expectation maximization (OSEM) without scatter correction (SC) using single-radionuclide (SR) data; (2) SR-MC-OSEM, OSEM with a fast MC-based SC using SR data; (3) DR-OSEM, OSEM without SC using dual-radionuclide (DR) data; and (4) DR-MC-JOSEM, joint OSEM with a fast MC-based SC using DR data. Ten 99mTc-MDP and ten 123I-MIBG data sets, which had tumors mathematically inserted, were also used to evaluate the performance of authors’ approach. For the phantom study, relative bias and relative standard deviation of tumor uptake were computed for each tumor using the tumor uptake in the noise-free single-radionuclide images, which were reconstructed by SR-MC-OSEM, as the gold standard. For both the phantom and constructed patient studies, mean contrast and standard deviation of contrast were computed for each tumor for both the single- and dual-radionuclide images. Additionally, contrast recovery was computed as the ratio between mean contrast and the mean contrast for SR-MC-OSEM. Results: For

  13. Higher nigrostriatal dopamine neuron loss in early than late onset Parkinson's disease?--a [99mTc]-TRODAT-1 SPECT study.

    PubMed

    Shih, Ming Chi; Franco de Andrade, Luiz Augusto; Amaro, Edson; Felicio, Andre Carvalho; Ferraz, Henrique Ballalai; Wagner, Jairo; Hoexter, Marcelo Queiroz; Lin, Li Fu; Fu, Ying Kai; Mari, Jair Jesus; Tufik, Sergio; Bressan, Rodrigo Affonseca

    2007-04-30

    Early-onset Parkinson's disease (EOPD) is distinct from the classic late-onset PD (LOPD) because of its slower disease progression. The aim of this study was to compare dopamine neuronal loss in EOPD with that of LOPD with the same disease duration, through dopamine transporter (DAT) estimation. Fourteen patients, seven EOPD (<50 years) and seven LOPD, matched for disease duration were scanned with [(99m)Tc]-TRODAT-1-SPECT (INER-Taiwan), and were assessed with standard PD scales. EOPD patients had 34% lower striatal DAT binding potential (BP) compared with that of LOPD patients (BP = 0.29 +/- 0.12, BP = 0.44 +/- 0.12, P < 0.02) with similar PD severity. These results suggest that EOPD patients have greater dopamine density loss than LOPD patients without motor-symptom worsening. PMID:17290452

  14. Tomographic studies of rCBF with (/sup 99m/Tc)-HM-PAO SPECT in patients with brain tumors: comparison with C VO2 continuous inhalation technique and PET

    SciTech Connect

    Langen, K.J.; Herzog, H.; Kuwert, T.; Roosen, N.; Rota, E.; Kiwit, J.C.; Bock, W.J.; Feinendegen, L.E.

    1988-12-01

    In 10 patients with malignant gliomas, the intracerebral distribution of (/sup 99m/Tc)-hexamethylpropylene-amine oxime ((/sup 99m/Tc)-HM-PAO) was studied with single photon emission computed tomography (SPECT) in comparison with C VO2 steady-state inhalation technique to measure cerebral blood flow using positron emission tomography (PET). In all instances, the cerebral (/sup 99m/Tc)-HM-PAO distribution was comparable with the regional pattern of cerebral blood flow (rCBF) observed with PET. This was confirmed by a significant correlation of tumor to cortex and tumor to white matter ratios between these two experimental methods. However, the contrast between high and low activity regions in the SPECT scans was significantly less than that in the PET scans. Contrast enhancement of the SPECT scans was accomplished using a correction formula proposed by Lassen.

  15. Using adaptive neuro-fuzzy inference system technique for crosstalk correction in simultaneous 99mTc/201Tl SPECT imaging: A Monte Carlo simulation study

    NASA Astrophysics Data System (ADS)

    Heidary, Saeed; Setayeshi, Saeed

    2015-01-01

    This work presents a simulation based study by Monte Carlo which uses two adaptive neuro-fuzzy inference systems (ANFIS) for cross talk compensation of simultaneous 99mTc/201Tl dual-radioisotope SPECT imaging. We have compared two neuro-fuzzy systems based on fuzzy c-means (FCM) and subtractive (SUB) clustering. Our approach incorporates eight energy-windows image acquisition from 28 keV to 156 keV and two main photo peaks of 201Tl (77±10% keV) and 99mTc (140±10% keV). The Geant4 application in emission tomography (GATE) is used as a Monte Carlo simulator for three cylindrical and a NURBS Based Cardiac Torso (NCAT) phantom study. Three separate acquisitions including two single-isotopes and one dual isotope were performed in this study. Cross talk and scatter corrected projections are reconstructed by an iterative ordered subsets expectation maximization (OSEM) algorithm which models the non-uniform attenuation in the projection/back-projection. ANFIS-FCM/SUB structures are tuned to create three to sixteen fuzzy rules for modeling the photon cross-talk of the two radioisotopes. Applying seven to nine fuzzy rules leads to a total improvement of the contrast and the bias comparatively. It is found that there is an out performance for the ANFIS-FCM due to its acceleration and accurate results.

  16. Assessment of cardiac function using myocardial perfusion imaging technique on SPECT with 99mTc sestamibi

    NASA Astrophysics Data System (ADS)

    Gani, M. R. A.; Nazir, F.; Pawiro, S. A.; Soejoko, D. S.

    2016-03-01

    Suspicion on coronary heart disease can be confirmed by observing the function of left ventricle cardiac muscle with Myocardial Perfusion Imaging techniques. The function perfusion itself is indicated by the uptake of radiopharmaceutical tracer. The 31 patients were studied undergoing the MPI examination on Gatot Soebroto Hospital using 99mTc-sestamibi radiopharmaceutical with stress and rest conditions. Stress was stimulated by physical exercise or pharmacological agent. After two hours, the patient did rest condition on the same day. The difference of uptake percentage between stress and rest conditions will be used to determine the malfunction of perfusion due to ischemic or infarct. Degradation of cardiac function was determined based on the image-based assessment of five segments of left ventricle cardiac. As a result, 8 (25.8%) patients had normal myocardial perfusion and 11 (35.5%) patients suspected for having partial ischemia. Total ischemia occurred to 8 (25.8%) patients with reversible and irreversible ischemia and the remaining 4 (12.9%) patients for partial infarct with characteristic the percentage of perfusion ≤50%. It is concluded that MPI technique of image-based assessment on uptake percentage difference between stress and rest conditions can be employed to predict abnormal perfusion as complementary information to diagnose the cardiac function.

  17. Biodistribution and kinetic studies of technetium-99m labeled Naja naja karachiensis venom via gamma scintigraphic and SPECT images.

    PubMed

    Bin-Asad, Muhammad Hassham-Hassan; e-Sabih, Durr; Ahmad, Israr; Choudhry, Bashir Ahmad; Murtaza, Ghulam; Hussain, Izhar

    2015-07-01

    Naja naja karachiensis have been responsible for plentiful deaths in Pakistan. To investigate bio distribution and blood kinetics, venom was labeled with the radiotracer (technetium-99m) by following the method of direct labeling technique. Its maximum labeling percentage was 97.7% (pH 6, 100 µg stannous chloride dihydrate) which was higher than some other reported venom. Radio labeled venom was stable for more than 4 hours both in vivo (96%) and in vitro (serum 94.1%, saline 94.3%) experimentations. Intravenous doses of venom (250 µg, 0.5 mCi) were found to be evenly distributed (having R/L ratio=1.0) in all parts of sacrificed rabbits. Kidneys (53.75% activity/g) and urinary bladder (23.70% activity/g) were found with the copious quantity of injected dose of venom. Rest of all other organs was found with subsequent remaining dose of venom. Among them, lungs (14.2% activity/g), liver (4.32% activity/g), bones (1.38% activity/g), heart (0.8% activity/g), blood (0.56% activity/g), skin (0.45% activity/g), intestines (0.35% activity/g), skeleton muscles (0.3% activity/g), brain (0.14% activity/g) and stomach (0.05% activity/g) are included. After 24 hours of injection, poisoned blood of rabbits was almost cleared from venom. Gamma scintigraphic images (up to 2 hours) along with bio distribution suggest that kidneys are main organs of excretion in rabbits. Elimination started immediately after administration of venom however, possible sites for metabolism of venom are liver and lungs. More accumulation of venom in heart compared to brain suggests its higher affinity (thus possible higher toxicity) to cardiac muscles as compared to brain tissues. PMID:26142502

  18. Design and preclinical evaluation of a 99mTc-labelled diabody of mAb J591 for SPECT imaging of prostate-specific membrane antigen (PSMA)

    PubMed Central

    2014-01-01

    Background Sensitive and specific detection of nodal status, sites of metastases and low-volume recurrent disease could greatly improve management of patients with advanced prostate cancer. Prostate-specific membrane antigen (PSMA) is a well-established marker for prostate carcinoma with increased levels of expression in high-grade, hormone-refractory and metastatic disease. The monoclonal antibody (mAb) J591 is directed against an extracellular epitope of PSMA and has been shown to efficiently target disseminated disease including metastases in lymph nodes and bone. Its use as a diagnostic imaging agent however is limited due to its slow pharmacokinetics. In this study a diabody derived from mAb J591 was developed as a single photon emission computed tomography (SPECT) tracer with improved pharmacokinetics for the detection of PSMA expression in prostate cancer. Methods A diabody in VH-VL orientation and with a C-terminal cysteine was expressed in HEK293T cells and purified by a combination of metal ion affinity and size exclusion chromatography. Specificity and affinity were determined in cell binding studies. For SPECT imaging, the diabody was site-specifically labelled with [99mTc(CO)3]+ via the C-terminal His tag and evaluated in a subcutaneous DU145/DU145-PSMA prostate carcinoma xenograft model. Results J591C diabody binds to PSMA-expressing cells with low nanomolar affinity (3.3 ± 0.2 nM). SPECT studies allowed imaging of tumour xenografts with high contrast from 4 h post injection (p.i.). Ex vivo biodistribution studies showed peak tumour uptake of the tracer of 12.1% ± 1.7% injected dose (ID)/g at 8 h p.i. with a tumour to blood ratio of 8.0. Uptake in PSMA-negative tumours was significantly lower with 6.3% ± 0.5% at 8 h p.i. (p < 0.001). Conclusion The presented diabody has favourable properties required to warrant its further development for antibody-based imaging of PSMA expression in prostate cancer, including PSMA-specific uptake

  19. Cerebral SPECT imaging: Impact on clinical management

    SciTech Connect

    Bloom, M.; Jacobs, S.; Pozniakof, T.

    1994-05-01

    Although cerebral SPECT has been reported to be of value in a variety of neurologic disorders, there is limited data available on the value of SPECT relative to clinical management decisions. The purpose of this study was to determine the effect of cerebral SPECT imaging on patient management. A total of 94 consecutive patients referred for clinical evaluation with brain SPECT were included in this study. Patients were assigned to one of nine groups depending on the clinical indication for the study. These groups included transient ischemia (16), stroke (20), dementia (18), seizures (5), hemorrhage (13), head trauma (6), arteriovenous malformations (6), encephalopathy (6) and a miscellaneous (4) group. All patients were injected with 99mTc HMPAO in doses ranging from 15 mCi to 22 mCi (555 MBq to 814 MBq) and scanned on a triple headed SPECT gamma camera. Two weeks after completion of the study, a standardized interview was conducted between the nuclear and referring physicians to determine if the SPECT findings contributed to an alteration in patient management. Overall, patient management was significantly altered in 47% of the cases referred. The greatest impact on patient management occurred in the group evaluated for transient ischemia, where a total of 13/16 (81%) of patients had their clinical management altered as a result of the cerebral SPECT findings. Clinical management was altered in 61% of patients referred for evaluation of dementia, 67% of patients evaluated for arteriovenous malformations, and 50% of patients with head trauma. In the remainder of the patients, alteration in clinical management ranged from 17% to 50% of patients. This study demonstrates the clinical utility of cerebral SPECT imaging since in a significant number of cases clinical management was altered as a result of the examination. Long term follow up will be necessary to determine patient outcome.

  20. Maximum Standardized Uptake Value of (99m)Tc Hydroxymethylene Diphosphonate SPECT/CT for the Evaluation of Temporomandibular Joint Disorder.

    PubMed

    Suh, Min Seok; Lee, Won Woo; Kim, Young-Kyun; Yun, Pil-Young; Kim, Sang Eun

    2016-09-01

    Purpose To evaluate the diagnostic accuracy of the quantitative parameter standardized uptake value (SUV) at single photon emission computed tomography (SPECT)/computed tomography (CT) for the evaluation of temporomandibular joint (TMJ) disorder (TMD). Materials and Methods This study was approved by the institutional review board, and the need for informed consent was waived. Forty-four TMJs in 22 patients with TMD (five men and 17 women; mean age ± standard deviation, 30.0 years ± 12.1) were evaluated. The patients underwent planar bone scintigraphy and SPECT/CT 3-4 hours after injection of technetium 99m hydroxymethylene diphosphonate. The planar scintigraphy parameter of relative ratio (RR) and SPECT/CT parameters mean SUV (SUVmean) and maximum SUV (SUVmax) were compared for the visual assessment of TMD on planar scintigraphy images and for the presence of TMJ arthralgia. Group comparisons, receiver operating characteristic analysis, and Pearson correlation analysis were conducted. Results SUVmax gradually increased from normal (2.82 ± 0.73) to mild or moderately abnormal (3.56 ± 0.76, P < .05) and then to severely abnormal (4.86 ± 1.25, P < .05). However, RR and SUVmean did not vary significantly according to visual grade (P > .05). On the other hand, SUVmax was significantly greater in arthralgic TMJs (4.15 ± 1.11) than in nonarthralgic TMJs (2.97 ± 0.75, P < .001), as was SUVmean (1.63 ± 0.42 vs 1.30 ± 0.31, respectively; P = .005). However, there was no significant difference in RR (3.61 ± 0.57 vs 3.76 ± 0.68, P = .45). In receiver operating characteristic curve analyses for arthralgic TMJ, SUVmax had the greatest area under the curve (area of 0.815). Conclusion SUVmax derived from bone SPECT/CT may be useful for the evaluation of TMD. (©) RSNA, 2016 Online supplemental material is available for this article. PMID:27035060

  1. TU-F-12A-04: Differential Radiation Avoidance of Functional Liver Regions Defined by 99mTc-Sulfur Colloid SPECT/CT with Proton Therapy

    SciTech Connect

    Bowen, S; Miyaoka, R; Kinahan, P; Sandison, G; Vesselle, H; Nyflot, M; Apisarnthanarax, S; Saini, J; Wong, T

    2014-06-15

    Purpose: Radiotherapy for hepatocellular carcinoma patients is conventionally planned without consideration of spatial heterogeneity in hepatic function, which may increase risk of radiation-induced liver disease. Pencil beam scanning (PBS) proton radiotherapy (pRT) plans were generated to differentially decrease dose to functional liver volumes (FLV) defined on [{sup 99m}Tc]sulfur colloid (SC) SPECT/CT images (functional avoidance plans) and compared against conventional pRT plans. Methods: Three HCC patients underwent SC SPECT/CT scans for pRT planning acquired 15 min post injection over 24 min. Images were reconstructed with OSEM following scatter, collimator, and exhale CT attenuation correction. Functional liver volumes (FLV) were defined by liver:spleen uptake ratio thresholds (43% to 90% maximum). Planning objectives to FLV were based on mean SC SPECT uptake ratio relative to GTV-subtracted liver and inversely scaled to mean liver dose of 20 Gy. PTV target coverage (V{sub 95}) was matched between conventional and functional avoidance plans. PBS pRT plans were optimized in RayStation for single field uniform dose (SFUD) and systematically perturbed to verify robustness to uncertainty in range, setup, and motion. Relative differences in FLV DVH and target dose heterogeneity (D{sub 2}-D{sub 98})/D50 were assessed. Results: For similar liver dose between functional avoidance and conventional PBS pRT plans (D{sub mean}≤5% difference, V{sub 18Gy}≤1% difference), dose to functional liver volumes were lower in avoidance plans but varied in magnitude across patients (FLV{sub 70%max} D{sub mean}≤26% difference, V{sub 18Gy}≤8% difference). Higher PTV dose heterogeneity in avoidance plans was associated with lower functional liver dose, particularly for the largest lesion [(D{sub 2}-D{sub 98})/D{sub 50}=13%, FLV{sub 90%max}=50% difference]. Conclusion: Differential avoidance of functional liver regions defined on sulfur colloid SPECT/CT is feasible with proton

  2. Quantitative evaluation of simultaneous reconstruction with model-based crosstalk compensation for 99mTc/123I dual-isotope simultaneous acquisition brain SPECT.

    PubMed

    Du, Yong; Frey, Eric C

    2009-06-01

    A model-based method has been previously developed to estimate and compensate for the crosstalk and downscatter contamination in simultaneous 123I/99mTc dual-isotope SPECT imaging. In this method, photon scatter in the object is modeled using the effective source scatter estimate technique. Photon interactions with the collimator-detector are estimated using precalculated Monte Carlo simulated point response functions. Two different approaches, simultaneous and alternating model-based compensations, have been proposed for iterative reconstruction-based crosstalk and downscatter contamination compensation. In this work, both model-based approaches were evaluated in the context of quantitative accuracy when imaging the dopaminergic system using both Monte Carlo simulated and experimentally acquired data. Results indicate that mddel-based estimates of the crosstalk and downscatter contamination in both energy windows were in good agreement with the truth for the simulated data. The effects of the contamination reduced image contrast and overestimated absolute activity in all structures by up to 66%. Compensation using both model-based approaches improved image contrast. Errors in absolute activity quantitation were also reduced to less than +/-5% for most brain structures. The accuracy of striatal specific binding potentials, calculated as the ratio of activity in various striatal structures to the background, was also greatly improved after model-based compensation. In conclusion, model-based compensation of simultaneously acquired images of 99mTc and 123I labeled brain imaging agents provided image quality and quantitative accuracy that were comparable to the image without crosstalk. Both proposed compensation approaches can potentially be applied clinically, but when reconstruction time is a limiting factor, the alternating model-based compensation may be preferable. PMID:19610291

  3. Sci—Thur PM: Imaging — 04: An iterative triple energy window (TEW) approach to cross talk correction in quantitative small animal Tc99m and In111 SPECT

    SciTech Connect

    Prior, P; Timmins, R; Wells, R G

    2014-08-15

    Dual isotope SPECT allows simultaneous measurement of two different tracers in vivo. With In111 (emission energies of 171keV and 245keV) and Tc99m (140keV), quantification of Tc99m is degraded by cross talk from the In111 photons that scatter and are detected at an energy corresponding to Tc99m. TEW uses counts recorded in two narrow windows surrounding the Tc99m primary window to estimate scatter. Iterative TEW corrects for the bias introduced into the TEW estimate resulting from un-scattered counts detected in the scatter windows. The contamination in the scatter windows is iteratively estimated and subtracted as a fraction of the scatter-corrected primary window counts. The iterative TEW approach was validated with a small-animal SPECT/CT camera using a 2.5mL plastic container holding thoroughly mixed Tc99m/In111 activity fractions of 0.15, 0.28, 0.52, 0.99, 2.47 and 6.90. Dose calibrator measurements were the gold standard. Uncorrected for scatter, the Tc99m activity was over-estimated by as much as 80%. Unmodified TEW underestimated the Tc99m activity by 13%. With iterative TEW corrections applied in projection space, the Tc99m activity was estimated within 5% of truth across all activity fractions above 0.15. This is an improvement over the non-iterative TEW, which could not sufficiently correct for scatter in the 0.15 and 0.28 phantoms.

  4. [Clinical usefulness of 201Tl/99mTc-PYP dual myocardial quantitative gated SPECT program using low-dose dobutamine loading in assessment of myocardial viability in patient with acute myocardial infarction--a case report].

    PubMed

    Irie, Hidekazu; Ito, Kazuki; Koide, Masahiro; Taniguchi, Takuya; Yokoi, Hirokazu; Nakamura, Reo; Kinoshita, Noriyuki; Hashimoto, Tetsuo; Tamaki, Shunichi; Sawada, Takahisa; Azuma, Akihiro; Matsubara, Hiroaki

    2006-05-01

    An 86-year-old man with chest pain was admitted to our hospital. Coronary angiography revealed 99% stenosis of the mid segment of the left anterior descending coronary artery, therefore, a coronary stent was implanted. Immediately after the stent implantation, 99% stenosis occurred at the proximal site of the 1st diagonal artery because of stent jeal. On the 4th hospital day, ECG-gated 201TL/99mTc-PYP dual myocardial quantitative gated SPECT was performed at rest and during low-dose dobutamine loading. The 201Tl scintigraphy revealed moderately reduced uptake in the anterior, septal and apical walls, and 99mTc-PYP uptake was observed in the mid-anterior wall. A three-dimensional surface display of gated 201Tl SPECT images showed severe hypokinesis in the anterior, septal and apical walls at rest. On the other hand, during low-dose dobutamine loading, improved wall motion was observed in the basal anterior and septal walls, while no change was observed in the midanterior and apical wall movements. Three-dimensional surface display of gated 201Tl/99mTc-PYP dual SPECT images revealed similar patterns of wall motion as those of gated 201Tl SPECT images at rest. During low-dose dobutamine loading, on the other hand, a three-dimensional surface display of gated 201Tl/99mTc-PYP dual SPECT images revealed improved wall motion in the basal anterior, septal and apical walls, but worsened wall motion of the mid-anterior wall. After 6 months, a follow-up coronary angiography revealed no re-stenosis of the stent, but 99% stenosis at the proximal aspect of the 1st diagonal artery. Left ventriculography revealed improved wall motion in the apex and akinesis of the mid-anterior wall. These wall motion findings were similar to those visualized in the three-dimensional surface display of gated 201Tl/99mTc-PYP dual SPECT images during low-dose dobutamine loading in the acute phase. These results suggest that 201Tl/99mTc-PYP dual myocardial quantitative gated SPECT using low

  5. Scatter and crosstalk corrections for {sup 99m}Tc/{sup 123}I dual-radionuclide imaging using a CZT SPECT system with pinhole collimators

    SciTech Connect

    Fan, Peng; Hutton, Brian F.; Holstensson, Maria; Ljungberg, Michael; Hendrik Pretorius, P.; Prasad, Rameshwar; Liu, Chi; Ma, Tianyu; Liu, Yaqiang; Wang, Shi; Thorn, Stephanie L.; Stacy, Mitchel R.; Sinusas, Albert J.

    2015-12-15

    Purpose: The energy spectrum for a cadmium zinc telluride (CZT) detector has a low energy tail due to incomplete charge collection and intercrystal scattering. Due to these solid-state detector effects, scatter would be overestimated if the conventional triple-energy window (TEW) method is used for scatter and crosstalk corrections in CZT-based imaging systems. The objective of this work is to develop a scatter and crosstalk correction method for {sup 99m}Tc/{sup 123}I dual-radionuclide imaging for a CZT-based dedicated cardiac SPECT system with pinhole collimators (GE Discovery NM 530c/570c). Methods: A tailing model was developed to account for the low energy tail effects of the CZT detector. The parameters of the model were obtained using {sup 99m}Tc and {sup 123}I point source measurements. A scatter model was defined to characterize the relationship between down-scatter and self-scatter projections. The parameters for this model were obtained from Monte Carlo simulation using SIMIND. The tailing and scatter models were further incorporated into a projection count model, and the primary and self-scatter projections of each radionuclide were determined with a maximum likelihood expectation maximization (MLEM) iterative estimation approach. The extracted scatter and crosstalk projections were then incorporated into MLEM image reconstruction as an additive term in forward projection to obtain scatter- and crosstalk-corrected images. The proposed method was validated using Monte Carlo simulation, line source experiment, anthropomorphic torso phantom studies, and patient studies. The performance of the proposed method was also compared to that obtained with the conventional TEW method. Results: Monte Carlo simulations and line source experiment demonstrated that the TEW method overestimated scatter while their proposed method provided more accurate scatter estimation by considering the low energy tail effect. In the phantom study, improved defect contrasts were

  6. PLA-PEG nanocapsules radiolabeled with 99mTechnetium-HMPAO: release properties and physicochemical characterization by atomic force microscopy and photon correlation spectroscopy.

    PubMed

    Pereira, Maira Alves; Mosqueira, Vanessa Carla Furtado; Vilela, José Mário Carneiro; Andrade, Margareth Spangler; Ramaldes, Gilson Andrade; Cardoso, Valbert Nascimento

    2008-01-01

    The present work describes the preparation, characterization and labelling of conventional and surface-modified nanocapsules (NC) with 99m Tc-HMPAO. The size, size distribution and homogeneity were determined by photon correlation spectroscopy (PCS) and zeta potential by laser doppler anemometry. The morphology and the structural organization were evaluated by atomic force microscopy (AFM). The stability and release profile of the NC were determined in vitro in plasma. The results showed that the use of methylene blue induces significant increase in the encapsulation efficiency of 99m Tc-HMPAO, from 24.4 to 49.8% in PLA NC and 22.37 to 52.93% in the case of PLA-PEG NC (P<0.05) by improving the complex stabilization. The average diameter of NC calculated by PCS varied from 216 to 323 nm, while the average diameter determined by AFM varied from 238 to 426 nm. The AFM analysis of diameter/height ratios suggested a greater homogeneity of the surface-modified PLA-PEG nanocapsules compared to PLA NC concerning their flattening properties. The in vitro release of the 99m Tc-HMPAO in plasma medium was faster for the conventional PLA NC than for the surface-modified NC. For the latter, 60% of the radioactivity remained associated with NC, even after 12h of incubation. The results suggest that the surface-modified 99m Tc-HMPAO-PLA-PEG NC was more stable against label leakage in the presence of proteins and could present better performance as radiotracer in vivo. PMID:17983736

  7. Quantitative measurements of cerebral blood flow using SPECT and (/sup 99m/Tc)-d,l-HM-PAO compared to xenon-133

    SciTech Connect

    Andersen, A.R.; Friberg, H.H.; Schmidt, J.F.; Hasselbalch, S.G.

    1988-12-01

    The uptake and retention in a 2 cm thick brain section was recorded serially by SPECT after i.v. injection of (99mTc)-d,l-HM-PAO (HM-PAO). In 16 patients, the fraction of the administered dose retained by the brain was 5.2 +/- 1%, showing a peak after 40-50s, then decreasing by 10% within the first 10 min and then by only 0.4% per hour. The image contrast was measured in each patient as the regional hemispheric asymmetry difference in percent of the highest value of the two regions. It decreased from 31% at 30-40 s to 25% at 10 min. At 24 h, a value of 19% was reached. Using the images obtained at 10 min after injection, a region to region comparison of the original and corrected HM-PAO images to the xenon-133 regional cerebral blood flow (rCBF) images was performed. Forty-four patients with stroke, epilepsy, dementia, basal ganglia disease, and tumors and control subjects were included in this comparison. The algorithm proposed by Lassen et al. was used to correct the original images for back diffusion of tracer (brain to blood); a good correlation very close to the line of identity between the corrected HM-PAO and xenon-133 data was obtained when using a conversion/clearance ratio of 1.5 and when the noninvolved hemisphere was used as a reference region (r = 0.86, p less than 0.0001). Serial arterial and cerebral venous blood sampling was performed over 10 min following i.v. injection of HM-PAO in six patients. An overall brain retention fraction of 0.37 +/- 0.03 (mean +/- SEM) was calculated from the data. An average CBF of 0.62 +/- 0.12 ml/g/min was determined on the basis of the Fick principle; this compared to a value of 0.59 +/- 0.09 ml/g/min (mean +/- SEM) measured by the xenon-133 inhalation method. The two sets of CBF values correlated linearly with a correlation coefficient of 0.97 (p less than 0.01).

  8. Diagnostic value of 18F-FDG PET in the assessment of myocardial viability in coronary artery disease: A comparative study with 99mTc SPECT and echocardiography

    PubMed Central

    Al Moudi, Mansour; Sun, Zhong-Hua

    2014-01-01

    Objective To investigate the diagnostic value of 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in the assessment of myocardial viability in patients with known coronary artery disease (CAD) when compared to 99mTc single photon emission computed tomography (SPECT) and echocardiography, with invasive coronary angiography as the gold standard. Methods Thirty patients with diagnosed CAD met the selection criteria, with 10 of them (9 men, mean age 59.5 ± 10.5 years) undergoing all of these imaging procedures consisting of SPECT and PET, echocardiography and invasive angiography. Diagnostic sensitivity of these less invasive modalities for detection of myocardial viability was compared to invasive coronary angiography. Inter- and intra-observer agreement was assessed for diagnostic performance of SPECT and PET. Results Of all patients with proven CAD, 50% had triple vessel disease. Diagnostic sensitivity of SPECT, PET and echocardiography was 90%, 100% and 80% at patient-based assessment, respectively. Excellent agreement was achieved between inter-observer and intra-observer agreement of the diagnostic value of SPECT and PET in myocardial viability (k = 0.9). Conclusion 18F-FDG PET has high diagnostic value in the assessment of myocardial viability in patients with known CAD when compared to SPECT and echocardiography. Further studies based on a large cohort with incorporation of 18F-FDG PET into patient management are warranted. PMID:25278972

  9. Reduced 123I Ioflupane Binding in Bilateral Diabetic Chorea: Findings With 18F FDG PET, 99mTc ECD SPECT, and 123I MIBG Scintigraphy.

    PubMed

    Sato, Kenichiro; Hida, Ayumi; Kameyama, Masashi; Morooka, Miyako; Takeuchi, Sousuke

    2016-06-01

    We report a 64-year-old man with diabetic chorea whom we investigated with dopamine transporter SPECT, F FDG PET, Tc ethylcysteinate dimer (ECD) SPECT, and I metaiodobenzylguanidine (MIBG) scintigraphy. Dopamine transporter SPECT revealed reduced I ioflupane binding in the bilateral striatum. F FDG PET showed metabolic dysfunction in the bilateral striatum, as shown in earlier studies. Tc ECD SPECT revealed reduced brain perfusion in the bilateral caudate nucleus and putamen. I MIBG scintigraphy revealed no cardiac sympathetic nerve dysfunction. Our case suggests a possible nigrostriatal presynaptic dopaminergic involvement in diabetic chorea. PMID:26975011

  10. Reproducibility of area at risk assessment in acute myocardial infarction by T1- and T2-mapping sequences in cardiac magnetic resonance imaging in comparison to Tc99m-sestamibi SPECT.

    PubMed

    Langhans, Birgit; Nadjiri, Jonathan; Jähnichen, Christin; Kastrati, Adnan; Martinoff, Stefan; Hadamitzky, Martin

    2014-10-01

    Area at risk (AAR) is an important parameter for the assessment of the salvage area after revascularization in acute myocardial infarction (AMI). By combining AAR assessment by T2-weighted imaging and scar quantification by late gadolinium enhancement imaging cardiovascular magnetic resonance (CMR) offers a promising alternative to the "classical" modality of Tc99m-sestamibi single photon emission tomography (SPECT). Current T2 weighted sequences for edema imaging in CMR are limited by low contrast to noise ratios and motion artifacts. During the last years novel CMR imaging techniques for quantification of acute myocardial injury, particularly the T1-mapping and T2-mapping, have attracted rising attention. But no direct comparison between the different sequences in the setting of AMI or a validation against SPECT has been reported so far. We analyzed 14 patients undergoing primary coronary revascularization in AMI in whom both a pre-intervention Tc99m-sestamibi-SPECT and CMR imaging at a median of 3.4 (interquartile range 3.3-3.6) days after the acute event were performed. Size of AAR was measured by three different non-contrast CMR techniques on corresponding short axis slices: T2-weighted, fat-suppressed turbospin echo sequence (TSE), T2-mapping from T2-prepared balanced steady state free precession sequences (T2-MAP) and T1-mapping from modified look locker inversion recovery (MOLLI) sequences. For each CMR sequence, the AAR was quantified by appropriate methods (absolute values for mapping sequences, comparison with remote myocardium for other sequences) and correlated with Tc99m-sestamibi-SPECT. All measurements were performed on a 1.5 Tesla scanner. The size of the AAR assessed by CMR was 28.7 ± 20.9 % of left ventricular myocardial volume (%LV) for TSE, 45.8 ± 16.6 %LV for T2-MAP, and 40.1 ± 14.4 %LV for MOLLI. AAR assessed by SPECT measured 41.6 ± 20.7 %LV. Correlation analysis revealed best correlation with SPECT for T2-MAP at a T2-threshold of 60 ms

  11. Simplified quantification method for in vivo SPECT/CT imaging of asialoglycoprotein receptor with (99m)Tc-p(VLA-co-VNI) to assess and stage hepatic fibrosis in mice.

    PubMed

    Zhang, Deliang; Guo, Zhide; Zhang, Pu; Li, Yesen; Su, Xinhui; You, Linyi; Gao, Mengna; Liu, Chang; Wu, Hua; Zhang, Xianzhong

    2016-01-01

    The goal of this study is to develop a noninvasive method of SPECT imaging to quantify and stage liver fibrosis with an Asialoglycoprotein receptor (ASGP-R) targeting tracer-(99m)Tc-p(VLA-co-VNI). ASGP-Rs are well known to specifically express in the mammalian liver. Here, we demonstrated ASGP-R expression decreased in carbon tetrachloride (CCl4)-induced mouse model. ASGP-R expression correlated with liver fibrosis progression. ASGP-R could be a useful marker in the stage of liver fibrosis. Liver uptake value (LUV) derived by SPECT imaging was used to assess liver fibrosis in the CCl4-induced mouse model. LUV = [radioactivity (liver uptake)/radioactivity (injected)] × 100/liver volume. The LUV decreased along with the disease progression. The relationships between LUV and liver hydroxyproline (i.e. collagen), as well as Sirius Red were established and verified. A strong negative linear correlation was found between LUV and hydroxyproline levels (r = -0.83) as well as LUV and Sirius Red quantification (r = -0.83). In conclusion, SPECT imaging with (99m)Tc-p(VLA-co-VNI) is useful in evaluating and staging liver fibrosis in vivo. PMID:27150943

  12. Simplified quantification method for in vivo SPECT/CT imaging of asialoglycoprotein receptor with 99mTc-p(VLA-co-VNI) to assess and stage hepatic fibrosis in mice

    PubMed Central

    Zhang, Deliang; Guo, Zhide; Zhang, Pu; Li, Yesen; Su, Xinhui; You, Linyi; Gao, Mengna; Liu, Chang; Wu, Hua; Zhang, Xianzhong

    2016-01-01

    The goal of this study is to develop a noninvasive method of SPECT imaging to quantify and stage liver fibrosis with an Asialoglycoprotein receptor (ASGP-R) targeting tracer—99mTc-p(VLA-co-VNI). ASGP-Rs are well known to specifically express in the mammalian liver. Here, we demonstrated ASGP-R expression decreased in carbon tetrachloride (CCl4)-induced mouse model. ASGP-R expression correlated with liver fibrosis progression. ASGP-R could be a useful marker in the stage of liver fibrosis. Liver uptake value (LUV) derived by SPECT imaging was used to assess liver fibrosis in the CCl4-induced mouse model. LUV = [radioactivity (liver uptake)/radioactivity (injected)] × 100/liver volume. The LUV decreased along with the disease progression. The relationships between LUV and liver hydroxyproline (i.e. collagen), as well as Sirius Red were established and verified. A strong negative linear correlation was found between LUV and hydroxyproline levels (r = −0.83) as well as LUV and Sirius Red quantification (r = −0.83). In conclusion, SPECT imaging with 99mTc-p(VLA-co-VNI) is useful in evaluating and staging liver fibrosis in vivo. PMID:27150943

  13. Liver Trapping of (99m)Tc Macroaggregated Albumin During Ventilation/Perfusion Scintigraphy in a Patient With Superior Vena Cava Stenosis as Demonstrated by SPECT/CT.

    PubMed

    Rousseau, Etienne; Leclerc, Yves; Prévost, Sylvain; Keu, Khun Visith

    2015-07-01

    A 50-year-old woman presented to our institution with a 1-day history of right posterior thoracic pain and dyspnea. She had a previous history of conservative resection of a high-grade basal-like infiltrating ductal carcinoma of the right breast 2 years before, subsequently treated by chemotherapy and radiotherapy. A ventilation and perfusion (VQ) scintigraphy performed for suspected pulmonary embolism showed an abnormal deposition of (99m)Tc macroaggregated albumin ((99m)Tc-MAA) in the left lobe of the liver. This unusual finding prompted additional imaging that demonstrated a superior vena cava stenosis. PMID:26018706

  14. Simultaneous Tc-99m/I-123 dual-radionuclide myocardial perfusion/innervation imaging using Siemens IQ-SPECT with SMARTZOOM collimator.

    PubMed

    Du, Yong; Bhattacharya, Manojeet; Frey, Eric C

    2014-06-01

    Simultaneous dual-radionuclide myocardial perfusion/innervation SPECT imaging can provide important information about the mismatch between scar tissue and denervated regions. The Siemens IQ-SPECT system developed for cardiac imaging uses a multifocal SMARTZOOM collimator to achieve a four-fold sensitivity for the cardiac region, compared to a typical parallel-hole low-energy high-resolution collimator, but without the data truncation that can result with conventional converging-beam collimators. The increased sensitivity allows shorter image acquisition times or reduced patient dose, making IQ-SPECT ideal for simultaneous dual-radionuclide SPECT, where reduced administrated activity is desirable in order to reduce patient radiation exposure. However, crosstalk is a major factor affecting the image quality in dual-radionuclide imaging. In this work we developed a model-based method that can estimate and compensate for the crosstalk in IQ-SPECT data. The crosstalk model takes into account interactions in the object and collimator-detector system. Scatter in the object was modeled using the effective source scatter estimation technique (ESSE), previously developed to model scatter with parallel-hole collimators. The geometric collimator-detector response was analytically modeled in the IQ-SPECT projector. The estimated crosstalk was then compensated for in an iterative reconstruction process. The new method was validated with data from both Monte Carlo simulations and physical phantom experiments. The results showed that the estimated crosstalk was in good agreement with simulated and measured results. After model-based compensation the images from simultaneous dual-radionuclide acquisitions were similar in quality to those from single-radionuclide acquisitions that did not have crosstalk contamination. The proposed model-based method can be used to improve simultaneous dual-radionuclide images acquired using IQ-SPECT. This work also demonstrates that ESSE scatter

  15. Simultaneous Tc-99m/I-123 Dual Radionuclide Myocardial Perfusion/Innervation Imaging Using Siemens IQ-SPECT with SMARTZOOM Collimator

    PubMed Central

    Du, Yong; Bhattacharya, Manojeet; Frey, Eric. C.

    2014-01-01

    Simultaneous dual-radionuclide myocardial perfusion/innervation SPECT imaging can provide important information about mismatch between scar tissue and denervated regions. The Siemens IQ-SPECT system developed for cardiac imaging uses a multifocal SMARTZOOM collimator to achieve a four-fold sensitivity for the cardiac region compared to a typical parallel-hole low-energy high-resolution collimator but without the data truncation that can result with conventional converging-beam collimators. The increased sensitivity allows shorter image acquisition times or reduced patient dose, making IQ-SPECT ideal for simultaneous dual-radionuclide SPECT, where reduced administrated activity is desirable in order to reduce patient radiation exposure. However, crosstalk is a major factor affecting the image quality in dual-radionuclide imaging. In this work we developed a model-based method that can estimate and compensate for the crosstalk in IQ-SPECT data. The crosstalk model takes into account interactions in the object and collimator-detector system. Scatter in the object was modeled using the effective source scatter estimation technique (ESSE), previously developed to model scatter with parallel-hole collimators. The geometric collimator detector response was analytically modeled in the IQ-SPECT projector. The estimated crosstalk was then compensated for in an iterative reconstruction process. The new method was validated with data from both Monte Carlo simulation and physical phantom experiments. The results showed that the estimated crosstalk was in good agreement with simulated and measured results. After model-based compensation the images from simultaneous dual-radionuclide acquisitions were similar in quality to those from single radionuclide acquisitions that did not have crosstalk contamination. The proposed model-based method can be used to improve simultaneous dual-radionuclide images acquired using IQ-SPECT. This work also demonstrates that ESSE scatter modeling

  16. Simultaneous Tc-99m/I-123 dual-radionuclide myocardial perfusion/innervation imaging using Siemens IQ-SPECT with SMARTZOOM collimator

    NASA Astrophysics Data System (ADS)

    Du, Yong; Bhattacharya, Manojeet; Frey, Eric C.

    2014-06-01

    Simultaneous dual-radionuclide myocardial perfusion/innervation SPECT imaging can provide important information about the mismatch between scar tissue and denervated regions. The Siemens IQ-SPECT system developed for cardiac imaging uses a multifocal SMARTZOOM collimator to achieve a four-fold sensitivity for the cardiac region, compared to a typical parallel-hole low-energy high-resolution collimator, but without the data truncation that can result with conventional converging-beam collimators. The increased sensitivity allows shorter image acquisition times or reduced patient dose, making IQ-SPECT ideal for simultaneous dual-radionuclide SPECT, where reduced administrated activity is desirable in order to reduce patient radiation exposure. However, crosstalk is a major factor affecting the image quality in dual-radionuclide imaging. In this work we developed a model-based method that can estimate and compensate for the crosstalk in IQ-SPECT data. The crosstalk model takes into account interactions in the object and collimator-detector system. Scatter in the object was modeled using the effective source scatter estimation technique (ESSE), previously developed to model scatter with parallel-hole collimators. The geometric collimator-detector response was analytically modeled in the IQ-SPECT projector. The estimated crosstalk was then compensated for in an iterative reconstruction process. The new method was validated with data from both Monte Carlo simulations and physical phantom experiments. The results showed that the estimated crosstalk was in good agreement with simulated and measured results. After model-based compensation the images from simultaneous dual-radionuclide acquisitions were similar in quality to those from single-radionuclide acquisitions that did not have crosstalk contamination. The proposed model-based method can be used to improve simultaneous dual-radionuclide images acquired using IQ-SPECT. This work also demonstrates that ESSE scatter

  17. Ischemic "memory image" in acute myocardial infarction of 123I-BMIPP after reperfusion therapy: a comparison with 99mTc-pyrophosphate and 201Tl dual-isotope SPECT.

    PubMed

    Mochizuki, Teruhito; Murase, Kenya; Higashino, Hiroshi; Miyagawa, Masao; Sugawara, Yoshifumi; Kikuchi, Takanori; Ikezoe, Junpei

    2002-12-01

    Ischemic "memory image" is a phenomenon of 123I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) in which an area at risk of acute myocardial infarction (AMI), could be detected as a defect in a couple of weeks even after successful reperfusion therapy. The purpose of this study was to clarify the incidence of the ischemic "memory image" of 123I-BMIPP in patients with AMI by comparing 99mTc-PYP and 201Tl dual-isotope SPECT. Materials consisted of 14 patients with successfully reperfused AMI and 20 patients with old myocardial infarction (OMI). All AMI patients underwent PYP/Tl dual-isotope SPECT within 1 week after the onset of AMI, and BMIPP SPECT was performed within 1 week after the PYP/Tl dual-isotope SPECT. The extent and severity of the defect of BMIPP and Tl were visually scored into four grades: 0 = no defect to 3 = large or severe defect. These scores were compared. PYP positive AMI lesions were concordant with BMIPP defects (13/14). In AMI, both the extent and severity scores of BMIPP were higher than 201Tl (p < 0.001). Differences (BMIPP - Tl) of extent and severity scores were greater in AMI than in OMI (p < 0.001). In conclusion, the ischemic "memory image" obtained by means of the BMIPP is a common phenomenon (13/14) in AMI, and helpful in evaluating the area at risk. PMID:12593422

  18. Bitemporal hypoperfusion in transient global amnesia: 99m-Tc-HM-PAO SPECT and neuropsychological findings during and after an attack.

    PubMed Central

    Stillhard, G; Landis, T; Schiess, R; Regard, M; Sialer, G

    1990-01-01

    We report a patient who was evaluated neuropsychologically and with single photon emission computed tomography (SPECT) during and after an episode of transient global amnesia. During the attack, there was patchy retrograde amnesia and an inability to learn both verbal and non-verbal material. SPECT showed severe bitemporal hypoperfusion. Serial neuro-psychological testing documented a rapid recovery of recognition, but delayed recovery in reproduction of learned information. Recovery of spontaneous verbal and figural fluency was even further delayed. Follow up SPECT examination showed a recovered cerebral perfusion. This case supports the hypothesis that TGA is associated with transient hypoperfusion of bilateral medial-temporal brain structures and suggests an additional involvement of structures responsible for drive and initiation. Images PMID:2341849

  19. Cerebral blood flow changes with acute cocaine intoxication: clinical correlations with SPECT, CT, and MRI.

    PubMed

    Mena, I; Giombetti, R J; Miller, B L; Garrett, K; Villanueva-Meyer, J; Mody, C; Goldberg, M A

    1994-01-01

    In summary, these data suggest that widespread primary or secondary cerebral vasoconstriction is common in patients with neurological complications from cocaine. In most patients, SPECT showed wide-spread hypoperfusion in regions that had no clear clinical significance (e.g., the periventricular area). In many, the SPECT was performed more than 24 hours after the onset of neurological symptomatology. These findings raise several questions. It has been assumed that these SPECT changes in patients with acute neurological symptoms are temporary, although it will be important to determine whether these areas of hypoperfusion persist after symptoms have abated. Recently, Holman and colleagues (1991) found multifocal and deep areas of hypoperfusion with SPECT in 16 of 18 patients with a history of chronic cocaine abuse. Although most of the subjects tested positive for cocaine, several had abstained from cocaine use for weeks prior to the study. All 18 subjects had neuropsychological deficits, 13 mild and 5 moderate. Similarly, Pascual-Leone and colleagues (1991) have shown that CT scan atrophy strongly correlates with the duration of cocaine abuse, suggesting that brain injury may occur with continued use of cocaine. It is the authors' concern that cocaine abuse might produce permanent changes in cerebral perfusion. In conclusion, brain SPECT was found to be a useful procedure in the evaluation of acute cocaine intoxication. Brain SPECT revealed focal cortical lesions not seen on head CT or MRI, which corresponded to clinical deficits. In addition, [99mTc]HMPAO brain SPECT had a characteristic scalloped appearance, and this may be a marker for acute intoxication with cocaine. This study further supports the contention that cocaine causes neurological disease by its vasoconstrictive action. PMID:7603541

  20. Technetium-99m nitrido dithiocarbamate complex with lateral ester groups: A potential agent for cerebral perfusion. Direct labeling and kinetic results in baboons

    SciTech Connect

    Bottlaender, M.; Bourguignon, M.; Maziere, M.

    1994-05-01

    Previous studies have shown that technetium-99m-nitrido (TcN) complexes of ester derivatives of dithiocarbamate cross the brain-blood barrier and one term of this class, namely the complex formed with sarcosine methyl ester dithiocarbamate (TcN-PR13) is retained in the brain of Cynomolgus monkeys. However these compounds were obtained through an in situ esterification of preformed TcN dicarboxylic derivative. We have been able to synthesize one term of this class of ligands, the sarcosine methylester dithiocarbamate, by reacting sarcosine with thionyl chloride in methanol to give the sarcosine methyl ester, which was reacted with carbon disulfide and NaOH in methanol to give the sodium salt of the dithiocarbamate derivative which was isolated as an oil. The corresponding TcN complex was obtained with a radiochemical purity greater than 96% by a kit method. The complex was injected in baboons and its radioactive distribution compared to that obtained with Tc-HMPAO. Blood and plasma kinetics were calculated from arterial sampling whereas tissue kinetics (brain, lungs) were obtained by ROI`s analysis. The values of the half-life in the blood were comparable for the two tracers, although the absolute activity was about 20% lower for TcN-PR13. The brain uptake of TcN-PR13 was 10% lower than that observed for Tc-HMPAO, and remained stable during 2 hours. TcN-PR13 displayed lower lung uptake and faster clearance from this organ than Tc-HMPAO. Brain/Lung ratios were 1.11 and 1.65 at 30 and 60 min for TcN-PR13 compared to 0.93 and 0.99 at the same time for Tc-HMPAO.

  1. Reduced hypothalamic blood flow after radiation treatment of nasopharyngeal cancer: SPECT studies in 34 patients

    SciTech Connect

    Chieng, P.U.; Huang, T.S.; Chang, C.C.; Chong, P.N.; Tien, R.D.; Su, C.T. )

    1991-07-01

    To determine the effect of cranial irradiation on hypothalamic blood flow, the authors performed 44 regional cerebral blood flow studies with 99mTc hexamethyl propyleneamine oxime (HMPAO) single-photon emission CT (SPECT) on four normal volunteers and 34 patients with pathologically proved nasopharyngeal cancer. Twenty-three men and 15 women, 30-65 years old, were divided into four study groups: group 1 served as a control and consisted of four normal volunteers and six patients studied prior to cranial irradiation; group 2 patients had cranial irradiation half a year before the SPECT study (n = 12, one from group 1); group 3 patients were irradiated 1 year before the study (n = 13, three from group 1 and two from group 2); and group 4 patients were irradiated at least 5 years before SPECT imaging (n = 9). Six patients were studied twice. Quantification of the 99mTc-HMPAO brain SPECT studies was done separately by three radiologists to obtain the hypothalamus/occipital (H/O) and hypothalamus/parasagittal (H/P) ratios. Endocrinologic studies were performed in all cases and the hypothalamus-thyrotroph-thyroid, hypothalamus-gonadotroph-testis (ovary), hypothalamus-lactotroph, hypothalamus-somatotroph, and hypothalamus-corticotroph-adrenal axes were evaluated separately. They determined that regional hypothalamic blood flow was reduced after cranial irradiation in patients with nasopharyngeal cancer. The H/O ratio of groups 3 and 4 did not differ from that of group 2 (one-half year after cranial irradiation). The H/O ratio was significantly reduced 6 months and 1 year after cranial irradiation; mean {plus minus} SD = 0.5801 {plus minus} 0.0829 (p less than .025), 0.5725 {plus minus} 0.0791 (p less than .01) versus 0.6477 {plus minus} 0.0458 before cranial irradiation, respectively.

  2. Follow-up (99m)Tc EC renal dynamic scintigraphy and DMSA-III SPECT/CT in unmasking a masqueraded case of Horseshoe kidney.

    PubMed

    Jain, T K; Basher, R K; Mittal, B R; Bhatia, A; Rao, K L N

    2015-01-01

    Hydronephrosis is a common finding in urinary tract outflow obstruction. Chronically obstructed hydronephrotic system may be associated with parenchymal changes. Ultrasound, intravenous urography, micturating cysto-urethrogram and scintigraphy are commonly performed to evaluate the cause of obstruction. In childhood, pelviureteric junction obstruction is a common cause of the hydronephrosis. Hydronephrosis can also be present in horseshoe kidneys due to poor drainage. However, a large sized hydronephrotic cavity may obscure the finding of horseshoe kidney. A case was reported, and it was diagnosed as horseshoe kidney on follow-up renal dynamic scan and confirmed with the help of dimercaptosuccinic acid SPECT/CT. PMID:26139030

  3. Performance of a novel collimator for high-sensitivity brain SPECT

    SciTech Connect

    El Fakhri, Georges; Ouyang Jinsong; Zimmerman, Robert E.; Fischman, Alan J.; Kijewski, Marie Foley

    2006-01-15

    We assessed improvements in performance in detection and estimation tasks due to a novel brain single photon computed tomography collimator. Data were acquired on the CeraSPECT{sup TM} scanner using both new and standard collimators. The new variable focusing collimator SensOgrade{sup TM} samples the projections unequally, with central regions more heavily represented, to compensate for attenuation of counts from central brain structures. Furthermore, it utilizes more of the cylindrical crystal surface. Two phantom studies were performed. The first phantom was a 21-cm-diameter cylindrical background containing nine spheres ranging from 0.5 to 5 cm{sup 3} in volume. {sup 99m}Tc sphere to background activity ratio was 10:1. Twenty-nine 10-min datasets were acquired with each collimator. The second phantom was the Radiology Support Devices (Long Beach, CA) striatal phantom with striatal-background ratios of 10:1 on the left and 5:1 on the right. Twenty-nine 4-min datasets were acquired with each collimator. Perfusion imaging using {sup 99m}Tc-HMPAO was also performed in three healthy volunteers using both collimators under identical simulations. Projections were reconstructed by filtered backprojection with an unwindowed ramp filter. The nonprewhitening matched filter signal-to-noise ratio (NPW-SNR) was computed as a surrogate for human performance in detecting spherical lesions. Sphere activity concentration, radius, and location coordinates were simultaneously estimated by fitting images to an assumed model using an iterative nonlinear algorithm. Resolution recovery was implicit in the estimation procedure, as the point spread function was incorporated into the model. NPW-SNR for sphere detection was 1.5 to 2 times greater with the new collimator; for the striatal phantom the improvement in SNR was 54%. The SNR for estimating sphere activity concentration improved by 46 to 89 % for spheres located more than 5 cm from the phantom center. Images acquired with the

  4. Growth Arrest Line Mimicking Lymphoma Involvement: The Findings of (99m)Tc-MDP Bone SPECT/CT and Serial Bone Scan in a Child with Non-Hodgkin's Lymphoma.

    PubMed

    Kim, Chanwoo; Kim, Ji Young; Choi, Yun Young; Lee, Seunghun; Lee, Young-Ho

    2016-06-01

    Growth arrest lines appear as dense sclerotic lines parallel to the growth plate of long bones on radiography. We describe the case of a 9-year-old female with growth arrest lines initially masquerading as lymphoma involvement on (99m)Tc-MDP bone scintigraphy who had been treated with chemotherapy for non-Hodgkin's lymphoma about 3 years previously. Subsequent regional bone SPECT/CT clearly diagnosed the growth arrest lines, and retrograde review of previous bone scintigraphy demonstrated line migration in this patient. Growth arrest lines should be considered a possible diagnosis on bone scintigraphy, especially in the surveillance of children who have experienced severe childhood infections, malnutrition, immobilization, or treatment with immunosuppressive or chemotherapeutic drugs that may inhibit bone growth. PMID:27275365

  5. Synthesis and Evaluation of Tricarbonyl (99m)Tc-Labeled 2-(4-Chloro)phenyl-imidazo[1,2-a]pyridine Analogs as Novel SPECT Imaging Radiotracer for TSPO-Rich Cancer.

    PubMed

    Choi, Ji Young; Iacobazzi, Rosa Maria; Perrone, Mara; Margiotta, Nicola; Cutrignelli, Annalisa; Jung, Jae Ho; Park, Do Dam; Moon, Byung Seok; Denora, Nunzio; Kim, Sang Eun; Lee, Byung Chul

    2016-01-01

    The 18-kDa translocator protein (TSPO) levels are associated with brain, breast, and prostate cancer progression and have emerged as viable targets for cancer therapy and imaging. In order to develop highly selective and active ligands with a high affinity for TSPO, imidazopyridine-based TSPO ligand (CB256, 3) was prepared as the precursor. (99m)Tc- and Re-CB256 (1 and 2, respectively) were synthesized in high radiochemical yield (74.5% ± 6.4%, decay-corrected, n = 5) and chemical yield (65.6%) by the incorporation of the [(99m)Tc(CO)₃(H₂O)₃]⁺ and (NEt₄)₂[Re(CO)₃Br₃] followed by HPLC separation. Radio-ligand 1 was shown to be stable (>99%) when incubated in human serum for 4 h at 37 °C with a relatively low lipophilicity (logD = 2.15 ± 0.02). The rhenium-185 and -187 complex 2 exhibited a moderate affinity (Ki = 159.3 ± 8.7 nM) for TSPO, whereas its cytotoxicity evaluated on TSPO-rich tumor cell lines was lower than that observed for the precursor. In vitro uptake studies of 1 in C6 and U87-MG cells for 60 min was found to be 9.84% ± 0.17% and 7.87% ± 0.23% ID, respectively. Our results indicated that (99m)Tc-CB256 can be considered as a potential new TSPO-rich cancer SPECT imaging agent and provides the foundation for further in vivo evaluation. PMID:27409602

  6. Synthesis and Evaluation of Tricarbonyl (99m)Tc-Labeled 2-(4-Chloro)phenyl-imidazo[1,2-a]pyridine Analogs as Novel SPECT Imaging Radiotracer for TSPO-Rich Cancer.

    PubMed

    Choi, Ji Young; Iacobazzi, Rosa Maria; Perrone, Mara; Margiotta, Nicola; Cutrignelli, Annalisa; Jung, Jae Ho; Park, Do Dam; Moon, Byung Seok; Denora, Nunzio; Kim, Sang Eun; Lee, Byung Chul

    2016-01-01

    The 18-kDa translocator protein (TSPO) levels are associated with brain, breast, and prostate cancer progression and have emerged as viable targets for cancer therapy and imaging. In order to develop highly selective and active ligands with a high affinity for TSPO, imidazopyridine-based TSPO ligand (CB256, 3) was prepared as the precursor. (99m)Tc- and Re-CB256 (1 and 2, respectively) were synthesized in high radiochemical yield (74.5% ± 6.4%, decay-corrected, n = 5) and chemical yield (65.6%) by the incorporation of the [(99m)Tc(CO)₃(H₂O)₃]⁺ and (NEt₄)₂[Re(CO)₃Br₃] followed by HPLC separation. Radio-ligand 1 was shown to be stable (>99%) when incubated in human serum for 4 h at 37 °C with a relatively low lipophilicity (logD = 2.15 ± 0.02). The rhenium-185 and -187 complex 2 exhibited a moderate affinity (Ki = 159.3 ± 8.7 nM) for TSPO, whereas its cytotoxicity evaluated on TSPO-rich tumor cell lines was lower than that observed for the precursor. In vitro uptake studies of 1 in C6 and U87-MG cells for 60 min was found to be 9.84% ± 0.17% and 7.87% ± 0.23% ID, respectively. Our results indicated that (99m)Tc-CB256 can be considered as a potential new TSPO-rich cancer SPECT imaging agent and provides the foundation for further in vivo evaluation. PMID:27399688

  7. Synthesis and Evaluation of Tricarbonyl (99m)Tc-Labeled 2-(4-Chloro)phenyl-imidazo[1,2-a]pyridine Analogs as Novel SPECT Imaging Radiotracer for TSPO-Rich Cancer.

    PubMed

    Choi, Ji Young; Iacobazzi, Rosa Maria; Perrone, Mara; Margiotta, Nicola; Cutrignelli, Annalisa; Jung, Jae Ho; Park, Do Dam; Moon, Byung Seok; Denora, Nunzio; Kim, Sang Eun; Lee, Byung Chul

    2016-01-01

    The 18-kDa translocator protein (TSPO) levels are associated with brain, breast, and prostate cancer progression and have emerged as viable targets for cancer therapy and imaging. In order to develop highly selective and active ligands with a high affinity for TSPO, imidazopyridine-based TSPO ligand (CB256, 3) was prepared as the precursor. (99m)Tc- and Re-CB256 (1 and 2, respectively) were synthesized in high radiochemical yield (74.5% ± 6.4%, decay-corrected, n = 5) and chemical yield (65.6%) by the incorporation of the [(99m)Tc(CO)₃(H₂O)₃]⁺ and (NEt₄)₂[Re(CO)₃Br₃] followed by HPLC separation. Radio-ligand 1 was shown to be stable (>99%) when incubated in human serum for 4 h at 37 °C with a relatively low lipophilicity (logD = 2.15 ± 0.02). The rhenium-185 and -187 complex 2 exhibited a moderate affinity (Ki = 159.3 ± 8.7 nM) for TSPO, whereas its cytotoxicity evaluated on TSPO-rich tumor cell lines was lower than that observed for the precursor. In vitro uptake studies of 1 in C6 and U87-MG cells for 60 min was found to be 9.84% ± 0.17% and 7.87% ± 0.23% ID, respectively. Our results indicated that (99m)Tc-CB256 can be considered as a potential new TSPO-rich cancer SPECT imaging agent and provides the foundation for further in vivo evaluation. PMID:27457557

  8. Synthesis and Evaluation of Tricarbonyl 99mTc-Labeled 2-(4-Chloro)phenyl-imidazo[1,2-a]pyridine Analogs as Novel SPECT Imaging Radiotracer for TSPO-Rich Cancer

    PubMed Central

    Choi, Ji Young; Iacobazzi, Rosa Maria; Perrone, Mara; Margiotta, Nicola; Cutrignelli, Annalisa; Jung, Jae Ho; Park, Do Dam; Moon, Byung Seok; Denora, Nunzio; Kim, Sang Eun; Lee, Byung Chul

    2016-01-01

    The 18-kDa translocator protein (TSPO) levels are associated with brain, breast, and prostate cancer progression and have emerged as viable targets for cancer therapy and imaging. In order to develop highly selective and active ligands with a high affinity for TSPO, imidazopyridine-based TSPO ligand (CB256, 3) was prepared as the precursor. 99mTc- and Re-CB256 (1 and 2, respectively) were synthesized in high radiochemical yield (74.5% ± 6.4%, decay-corrected, n = 5) and chemical yield (65.6%) by the incorporation of the [99mTc(CO)3(H2O)3]+ and (NEt4)2[Re(CO)3Br3] followed by HPLC separation. Radio-ligand 1 was shown to be stable (>99%) when incubated in human serum for 4 h at 37 °C with a relatively low lipophilicity (logD = 2.15 ± 0.02). The rhenium-185 and -187 complex 2 exhibited a moderate affinity (Ki = 159.3 ± 8.7 nM) for TSPO, whereas its cytotoxicity evaluated on TSPO-rich tumor cell lines was lower than that observed for the precursor. In vitro uptake studies of 1 in C6 and U87-MG cells for 60 min was found to be 9.84% ± 0.17% and 7.87% ± 0.23% ID, respectively. Our results indicated that 99mTc-CB256 can be considered as a potential new TSPO-rich cancer SPECT imaging agent and provides the foundation for further in vivo evaluation.

  9. A standardized method for the construction of tracer specific PET and SPECT rat brain templates: validation and implementation of a toolbox.

    PubMed

    Vállez Garcia, David; Casteels, Cindy; Schwarz, Adam J; Dierckx, Rudi A J O; Koole, Michel; Doorduin, Janine

    2015-01-01

    High-resolution anatomical image data in preclinical brain PET and SPECT studies is often not available, and inter-modality spatial normalization to an MRI brain template is frequently performed. However, this procedure can be challenging for tracers where substantial anatomical structures present limited tracer uptake. Therefore, we constructed and validated strain- and tracer-specific rat brain templates in Paxinos space to allow intra-modal registration. PET [18F]FDG, [11C]flumazenil, [11C]MeDAS, [11C]PK11195 and [11C]raclopride, and SPECT [99mTc]HMPAO brain scans were acquired from healthy male rats. Tracer-specific templates were constructed by averaging the scans, and by spatial normalization to a widely used MRI-based template. The added value of tracer-specific templates was evaluated by quantification of the residual error between original and realigned voxels after random misalignments of the data set. Additionally, the impact of strain differences, disease uptake patterns (focal and diffuse lesion), and the effect of image and template size on the registration errors were explored. Mean registration errors were 0.70 ± 0.32 mm for [18F]FDG (n = 25), 0.23 ± 0.10mm for [11C]flumazenil (n = 13), 0.88 ± 0.20 mm for [11C]MeDAS (n = 15), 0.64 ± 0.28 mm for [11C]PK11195 (n = 19), 0.34 ± 0.15 mm for [11C]raclopride (n = 6), and 0.40 ± 0.13 mm for [99mTc]HMPAO (n = 15). These values were smallest with tracer-specific templates, when compared to the use of [18F]FDG as reference template (p<0.001). Additionally, registration errors were smallest with strain-specific templates (p<0.05), and when images and templates had the same size (p ≤ 0.001). Moreover, highest registration errors were found for the focal lesion group (p<0.005) and the diffuse lesion group (p = n.s.). In the voxel-based analysis, the reported coordinates of the focal lesion model are consistent with the stereotaxic injection procedure. The use of PET/SPECT strain- and tracer

  10. A Standardized Method for the Construction of Tracer Specific PET and SPECT Rat Brain Templates: Validation and Implementation of a Toolbox

    PubMed Central

    Vállez Garcia, David; Casteels, Cindy; Schwarz, Adam J.; Dierckx, Rudi A. J. O.; Koole, Michel; Doorduin, Janine

    2015-01-01

    High-resolution anatomical image data in preclinical brain PET and SPECT studies is often not available, and inter-modality spatial normalization to an MRI brain template is frequently performed. However, this procedure can be challenging for tracers where substantial anatomical structures present limited tracer uptake. Therefore, we constructed and validated strain- and tracer-specific rat brain templates in Paxinos space to allow intra-modal registration. PET [18F]FDG, [11C]flumazenil, [11C]MeDAS, [11C]PK11195 and [11C]raclopride, and SPECT [99mTc]HMPAO brain scans were acquired from healthy male rats. Tracer-specific templates were constructed by averaging the scans, and by spatial normalization to a widely used MRI-based template. The added value of tracer-specific templates was evaluated by quantification of the residual error between original and realigned voxels after random misalignments of the data set. Additionally, the impact of strain differences, disease uptake patterns (focal and diffuse lesion), and the effect of image and template size on the registration errors were explored. Mean registration errors were 0.70±0.32mm for [18F]FDG (n = 25), 0.23±0.10mm for [11C]flumazenil (n = 13), 0.88±0.20 mm for [11C]MeDAS (n = 15), 0.64±0.28mm for [11C]PK11195 (n = 19), 0.34±0.15mm for [11C]raclopride (n = 6), and 0.40±0.13mm for [99mTc]HMPAO (n = 15). These values were smallest with tracer-specific templates, when compared to the use of [18F]FDG as reference template (p&0.001). Additionally, registration errors were smallest with strain-specific templates (p&0.05), and when images and templates had the same size (p≤0.001). Moreover, highest registration errors were found for the focal lesion group (p&0.005) and the diffuse lesion group (p = n.s.). In the voxel-based analysis, the reported coordinates of the focal lesion model are consistent with the stereotaxic injection procedure. The use of PET/SPECT strain- and tracer-specific templates allows

  11. Preparation and biological evaluation of (99m)Tc-ropinirole as a novel radiopharmaceutical for brain imaging.

    PubMed

    Motaleb, M A; Ibrahem, I T; Ayoub, V R; Geneidi, A S

    2016-04-01

    Noninvasive brain imaging is a process that allows scientists and physicians to view and monitor the areas of the brain. The aim of this study was to formulate a novel radiopharmaceutical for the detection of brain disorders at early stages in susceptible patients. (99m) Tc-ropinirole was prepared by the direct complexation of ropinirole with technetium-99m. The results showed that the radiochemical yield (99m) Tc-ropinirole was 92 ± 2.87% and the radiochemical yield was evaluated by paper chromatography and HPLC. In vitro studies showed that the formed complex was stable for up to 6 h. In vivo uptake of (99m) Tc-ropinirole in the brain was 4.87 ± 0.15% injected dose/g organ at 30 min post-injection, which cleared from the brain with time till it reaches 2.3% at 2 h post-injection indicating that the brain uptake of (99m) Tc-ropinirole is higher than that of the commercially available (99m) Tc-HMPAO, which is 2.25% at 30 min. Pre-dosing mice with cold ropinirole reduced the brain uptake to 0.26 ± 0.01% injected dose/g organ, so this confirms the high specificity and selectivity of this radiotracer for the assessment of the dopamine receptors. PMID:26913705

  12. Brain perfusion SPECT with Brodmann areas analysis in differentiating frontotemporal dementia subtypes.

    PubMed

    Valotassiou, Varvara; Papatriantafyllou, John; Sifakis, Nikolaos; Tzavara, Chara; Tsougos, Ioannis; Psimadas, Dimitrios; Kapsalaki, Eftychia; Fezoulidis, Ioannis; Hadjigeorgiou, George; Georgoulias, Panagiotis

    2014-01-01

    Despite the known validity of clinical diagnostic criteria, significant overlap of clinical symptoms between Frontotemporal dementia (FTD) subtypes exists in several cases, resulting in great uncertainty of the diagnostic boundaries. We evaluated the perfusion between FTD subtypes using brain perfusion (99m)Tc-HMPAO SPECT with Brodmann areas (BA) mapping. NeuroGam software was applied on single photon emission computed tomographic (SPECT) studies for the semi-quantitative evaluation of perfusion in BA and the comparison with the software's normal database. We studied 91 consecutive FTD patients: 21 with behavioural variants (bvFTD), 39 with language variants (lvFTD) [12 with progressive non-fluent aphasia (PNFA), 27 with semantic dementia (SD)], and 31 patients with progressive supranuclear palsy (PSP)/corticobasal degeneration (CBD). Stepwise logistic regression analyses showed that the BA 28L and 32R could independently differentiate bvFTD from lvFTD, while the BA 8R and 25R could discriminate bvFTD from SD and PNFA, respectively. Additionally, BA 7R and 32R were found to discriminate bvFTD from CBD/PSP. The only BA that could differentiate SD from PNFA was 6L. BA 6R and 20L were found to independently differentiate CBD/PSP from lvFTD. Moreover, BA 20L and 22R could discriminate CBD/PSP from PNFA, while BA 6R, 20L and 45R were found to independently discriminate CBD/PSP from SD. Brain perfusion SPECT with BA mapping can be a useful additional tool in differentiating FTD variants by improving the definition of brain areas that are specifically implicated, resulting in a more accurate differential diagnosis in atypical or uncertain forms of FTD. PMID:25387340

  13. Technetium-99m hexamethylpropylene amine oxime leucocyte scintigraphy in the differential diagnosis of cerebral abscesses.

    PubMed

    Spinelli, F; Sara, R; Milella, M; Ruffini, L; Sterzi, R; Causarano, I R; Sberna, M

    2000-01-01

    The diagnosis of brain abscess is often difficult, as the clinical symptoms are not specific. Computed tomography (CT) and magnetic resonance imaging (MRI) are highly sensitive, but different cerebral lesions, especially neoplasms, can have the same ring-like contrast enhancement. Brain abscess is a severe illness requiring rapid diagnosis to choose the most appropriate therapy. Technetium-99m hexamethylpropylene amine oxime (HMPAO)-labelled leucocyte scintigraphy is commonly used to detect an inflammatory process. The aim of this study was to present the results obtained with leucocyte scintigraphy in 65 patients with intracranial mass lesions and clinical findings compatible to or suggestive of brain abscess. The final diagnosis, based on surgery, clinical findings and stereotatic puncture, was brain abscess in 17 patients, primary brain neoplasm in 22, brain metastasis in 16, lymphoma in 2, cysticercosis in 2, hematoma in 2 and cerebral infarction in 4. 99mTc-HMPAO leucocyte scintigraphy was positive in all abscess cases. The scan was negative in the rest of the patients examined, with the exception of one lesion, which was finally diagnosed as a tumour (1 false-positive). All patients who did not have false-negative scans were treated with steroids. The sensitivity, specificity and diagnostic accuracy of leucocyte scintigraphy was 100%, 97.8% and 98.4%, respectively. In conclusion, in our experience, leucocyte scintigraphy is a valuable aid in the differential diagnosis between abscess and neoplasm. PMID:10654146

  14. Technetium-99m generator system

    DOEpatents

    Mirzadeh, S.; Knapp, F.F. Jr.; Collins, E.D.

    1998-06-30

    A {sup 99}Mo/{sup 99m}Tc generator system includes a sorbent column loaded with a composition containing {sup 99}Mo. The sorbent column has an effluent end in fluid communication with an anion-exchange column for concentrating {sup 99m}Tc eluted from the sorbent column. A method of preparing a concentrated solution of {sup 99m}Tc includes the general steps of: (a) providing a sorbent column loaded with a composition containing {sup 99}Mo, the sorbent column having an effluent end in fluid communication with an anion-exchange column; (b) eluting the sorbent column with a salt solution to elute {sup 99m}Tc from the sorbent and to trap and concentrate the eluted {sup 99m}Tc on the ion-exchange column; and (c) eluting the concentrated {sup 99m}Tc from the ion-exchange column with a solution comprising a reductive complexing agent. 1 fig.

  15. Technetium-99m generator system

    DOEpatents

    Mirzadeh, Saed; Knapp, Jr., Furn F.; Collins, Emory D.

    1998-01-01

    A .sup.99 Mo/.sup.99m Tc generator system includes a sorbent column loaded with a composition containing .sup.99 Mo. The sorbent column has an effluent end in fluid communication with an anion-exchange column for concentrating .sup.99m Tc eluted from the sorbent column. A method of preparing a concentrated solution of .sup.99m Tc includes the general steps of: a. providing a sorbent column loaded with a composition containing .sup.99 Mo, the sorbent column having an effluent end in fluid communication with an anion-exchange column; b. eluting the sorbent column with a salt solution to elute .sup.99m Tc from the sorbent and to trap and concentrate the eluted .sup.99m Tc on the ion-exchange column; and c. eluting the concentrated .sup.99m Tc from the ion-exchange column with a solution comprising a reductive complexing agent.

  16. Decreased regional cerebral blood flow in the bilateral thalami and medulla oblongata determined by an easy Z-score (eZIS) analysis of (99m)Tc-ECD-SPECT images in a case of MM2-thalamic-type sporadic Creutzfeldt-Jakob disease.

    PubMed

    Hayashi, Yuichi; Iwasaki, Yasushi; Yoshikura, Nobuaki; Asano, Takahiko; Hatano, Taku; Tatsumi, Shinsui; Satoh, Katsuya; Kimura, Akio; Kitamoto, Tetsuyuki; Yoshida, Mari; Inuzuka, Takashi

    2015-11-15

    We report a case of autopsy-verified MM2-thalamic-type sporadic Creutzfeldt-Jakob disease (sCJD) in a 46-year-old patient with a 16-month history of abnormal behavior, progressive dementia, insomnia, and speech disturbances without family history. Neurological examination revealed progressive dementia, frontal signs, insomnia, speech disturbance, gait disturbance and bilaterally exaggerated tendon reflexes. Both brain MRI and cerebrospinal fluid examinations, including 14-3-3 protein, yielded normal results. An easy Z-score (eZIS) analysis for (99m)Tc-ethyl cysteinate dimer-single photon emission computed tomography ((99m)Tc-ECD-SPECT) revealed decreased regional cerebral blood flow in the bilateral thalami and medulla oblongata. PRNP gene analysis revealed methionine homozygosity at codon 129 without mutation. Neuropathological examinations revealed severe neuronal loss, gliosis, and hypertrophic astrocytosis in the medial thalamus and inferior olivary nucleus. A slight depletion of Purkinje cells was observed. PrP immunostaining showed no obvious PrP deposits in the basal ganglia, thalamus, cerebellum, or brainstem; however, mild synaptic-type PrP deposits with some smaller plaque-like structures were only partially observed in the localized region of the frontal lobe with the spongiform change. Western blot analyses of protease-resistant PrP showed a type 2 pattern. In conclusion, eZIS analysis of (99m)Tc-ECD-SPECT images is useful for detecting both thalamic and medullary lesions. This is the first case of medullary lesions detected in a live patient with MM2-thalamic-type sCJD using SPECT. PMID:26421831

  17. Acceptance test of a commercially available software for automatic image registration of computed tomography (CT), magnetic resonance imaging (MRI) and 99mTc-methoxyisobutylisonitrile (MIBI) single-photon emission computed tomography (SPECT) brain images.

    PubMed

    Loi, Gianfranco; Dominietto, Marco; Manfredda, Irene; Mones, Eleonora; Carriero, Alessandro; Inglese, Eugenio; Krengli, Marco; Brambilla, Marco

    2008-09-01

    This note describes a method to characterize the performances of image fusion software (Syntegra) with respect to accuracy and robustness. Computed tomography (CT), magnetic resonance imaging (MRI), and single-photon emission computed tomography (SPECT) studies were acquired from two phantoms and 10 patients. Image registration was performed independently by two couples composed of one radiotherapist and one physicist by means of superposition of anatomic landmarks. Each couple performed jointly and saved the registration. The two solutions were averaged to obtain the gold standard registration. A new set of estimators was defined to identify translation and rotation errors in the coordinate axes, independently from point position in image field of view (FOV). Algorithms evaluated were local correlation (LC) for CT-MRI, normalized mutual information (MI) for CT-MRI, and CT-SPECT registrations. To evaluate accuracy, estimator values were compared to limiting values for the algorithms employed, both in phantoms and in patients. To evaluate robustness, different alignments between images taken from a sample patient were produced and registration errors determined. LC algorithm resulted accurate in CT-MRI registrations in phantoms, but exceeded limiting values in 3 of 10 patients. MI algorithm resulted accurate in CT-MRI and CT-SPECT registrations in phantoms; limiting values were exceeded in one case in CT-MRI and never reached in CT-SPECT registrations. Thus, the evaluation of robustness was restricted to the algorithm of MI both for CT-MRI and CT-SPECT registrations. The algorithm of MI proved to be robust: limiting values were not exceeded with translation perturbations up to 2.5 cm, rotation perturbations up to 10 degrees and roto-translational perturbation up to 3 cm and 5 degrees. PMID:17549564

  18. Compression type stress fracture of femoral neck with equivocal X-ray features diagnosed on 99mTc-MDP SPECT/CT in a case of trivial hip pain

    PubMed Central

    Vitalkar, Saurabh; Manglunia, Ashmi S.; Kulkarni, Arvind; Puranik, Ameya D.

    2016-01-01

    Stress insufficiency fracture is usually diagnosed clinically and on the basis of routine X-ray imaging findings. However, the absence of any known predisposing factors and negative or occult radiographic findings pose diagnostic challenges. We report the case of an elderly male patient who presented with a chief complaint of trivial left hip pain and with equivocal radiographic findings. Triphasic 99mTc-methylene diphosphonate bone scan and single-photon emission computed tomography/computed tomography helped in arriving at the diagnosis of stress insufficiency fracture involving femoral neck. PMID:27385898

  19. Compression type stress fracture of femoral neck with equivocal X-ray features diagnosed on (99m)Tc-MDP SPECT/CT in a case of trivial hip pain.

    PubMed

    Vitalkar, Saurabh; Manglunia, Ashmi S; Kulkarni, Arvind; Puranik, Ameya D

    2016-01-01

    Stress insufficiency fracture is usually diagnosed clinically and on the basis of routine X-ray imaging findings. However, the absence of any known predisposing factors and negative or occult radiographic findings pose diagnostic challenges. We report the case of an elderly male patient who presented with a chief complaint of trivial left hip pain and with equivocal radiographic findings. Triphasic (99m)Tc-methylene diphosphonate bone scan and single-photon emission computed tomography/computed tomography helped in arriving at the diagnosis of stress insufficiency fracture involving femoral neck. PMID:27385898

  20. Use of technetium-99m isonitrile (RP-30A) in assessing left ventricular perfusion and function at rest and during exercise in coronary artery disease, and comparison with coronary arteriography and exercise thallium-201 SPECT imaging

    SciTech Connect

    Iskandrian, A.S.; Heo, J.; Kong, B.; Lyons, E.; Marsch, S. )

    1989-08-01

    This study compared the results of stress and rest single-photon emission computed tomography imaging of myocardial perfusion using technetium-99m isonitrile (RP-30A) with the results of stress and redistribution tomographic thallium imaging and the results of coronary arteriography in 39 patients, 11 without and 28 with coronary artery disease (CAD). Each patient underwent 2 exercise studies at identical workload, heart rate and double product. In a subset of 13 patients, concomitant evaluation of left ventricular (LV) function using first-pass radionuclide angiography with a multi-crystal camera also was performed with bolus injections of isonitrile. Isonitrile had similar sensitivity (82 vs 82%, difference not significant), a slightly--but not significantly--higher specificity (100 vs 82%) and similar predictive accuracy (87 vs 82%) to thallium-201. The tracer uptake was assessed in 20 segments/study. There was concordance between the isonitrile and thallium-201 images in 723 of the 780 segments (93%) (kappa = 0.83 +/- 0.02). In general, the isonitrile images were considered of better quality than the thallium-201 images. All 10 patients with CAD who underwent concomitant first-pass radionuclide angiography had either perfusion abnormalities or an abnormal ejection fraction response to exercise. Thus, technetium-99m isonitrile provides a reliable method of assessment of CAD with a sensitivity, specificity and predictive accuracy comparable to that of exercise thallium-201 imaging. Additional advantages include better image quality and the ability to obtain concomitant assessment of LV function with the use of first-pass radionuclide angiography.

  1. A neutral technetium-99m complex for myocardial imaging

    SciTech Connect

    Narra, R.K.; Nunn, A.D.; Kuczynski, B.L.; Feld, T.; Wedeking, P.; Eckelman, W.C. )

    1989-11-01

    Technetium-99m-CDO-MeB (Bis(1,2-cyclohexanedione-dioximato(1-)- O)-(1,2-cyclohexanedione dioximato(2-)-O)methyl-borato(2-)- N,N',N'',N''',N'''',N''''')-chlorotechnetium belongs to a family of compounds generally known as boronic acid adducts of technetium dioxime complexes (BATOs). It has an intrinsic affinity for the myocardium, with negligible lung activity and rapid blood clearance. The uptake of 3.44% ID in rat heart at 1 min postinjection for ({sup 99m}Tc)CDO-MeB versus 3.03% for {sup 201}TI indicates high extraction of ({sup 99m}Tc)CDO-MeB by the myocardium. In dogs an ischemic defect is clearly seen in SPECT images obtained 10 min after injection of ({sup 99m}Tc)CDO-MeB. Tissue distribution data in rats show that ({sup 99m}Tc)CDO-MeB is excreted primarily in the feces and to a lesser extent in the urine. Approximately 80% of the activity is excreted within 24 hr after injection.

  2. Comparison of an adaptive neuro-fuzzy inference system and an artificial neural network in the cross-talk correction of simultaneous 99 m Tc / 201Tl SPECT imaging using a GATE Monte-Carlo simulation

    NASA Astrophysics Data System (ADS)

    Heidary, Saeed; Setayeshi, Saeed; Ghannadi-Maragheh, Mohammad

    2014-09-01

    The aim of this study is to compare the adaptive neuro-fuzzy inference system (ANFIS) and the artificial neural network (ANN) to estimate the cross-talk contamination of 99 m Tc / 201 Tl image acquisition in the 201 Tl energy window (77 ± 15% keV). GATE (Geant4 Application in Emission and Tomography) is employed due to its ability to simulate multiple radioactive sources concurrently. Two kinds of phantoms, including two digital and one physical phantom, are used. In the real and the simulation studies, data acquisition is carried out using eight energy windows. The ANN and the ANFIS are prepared in MATLAB, and the GATE results are used as a training data set. Three indications are evaluated and compared. The ANFIS method yields better outcomes for two indications (Spearman's rank correlation coefficient and contrast) and the two phantom results in each category. The maximum image biasing, which is the third indication, is found to be 6% more than that for the ANN.

  3. Accessory spleen mimicking pancreatic tumour: evaluation by 99mTc-labelled colloid SPECT/CT study. Report of two cases and a review of nuclear medicine methods utility.

    PubMed

    Pachowicz, M; Mocarska, A; Starosławska, E; Pietrzyk, Ł; Chrapko, B

    2015-01-01

    The accessory spleen is a common congenital anomaly, typically asymptomatic and harmless to the patient. However, in some clinical cases, this anomaly beco-mes significant as it can be mistaken for a tumour or lymph node and be missed during a therapeutic splenectomy. There are nuclear medicine modalities which can be applied in the identification and localisation of an accessory spleen. They include scintigraphy with radiolabelled colloids or heat damaged red blood cells, which are trapped in the splenic tissue. Modern techniques, including hybrid imaging, enable simultaneous structure and tracer distribution evaluations. Additionally, radiation-guided surgery can be used in cases where the accessory spleen, which is usually small (not exceeding 1 cm) and difficult to find among other tissues, has to be removed. In the study, we would like to present 2 cases of patients in which the malignancy had to be excluded for the reason that the multiple accessory spleens were very closely related to the pancreas. There was a lack of certainty in the multi-phase computed tomography (CT) evaluation; however, this situation was clearly resolved by using the 99mTc-stannous colloid single photon emission computed tomography/ CT study. We would also like to briefly analyse the clinical applications of nuclear medicine in case of an accessory spleen. PMID:26620518

  4. Development of Tc-99m Imaging Agents for Abeta Plaques

    SciTech Connect

    Zhi-Ping, Zhuang; Mei-Ping Kung; Catherihne Hou; Hank F. Kung

    2008-09-26

    Development of SPECT imaging agents based on Tc-99m targeting Aβ plaques is useful for diagnosis of Alzheimer’s disease (AD). A stilbene derivative, [11C]SB-13, showing promise in detecting senile plaques present in AD patients has been reported previously1,2. Based on the 4’-amino-stilbene core structure we have added substituted groups through which a chelating group, N2S2, was conjugated. We report herein a series of Tc-99m labeled stilbene derivative conjugated with a TcO[N2S2] core. The syntheses of stilbenes containing a N2S2 chelating ligand are achieved by a scheme shown. Lipophilic 99mTc stilbene complexes were successfully prepared and purified through HPLC. Preliminary results of in vitro labeling of brain sections from transgenic mice showed very promising plaque labeling. These 99mTc stilbene derivatives are warranted for further evaluations as potential imaging agents targeting amyloid plaques.

  5. Impact of boronate capping groups on biological characteristics of novel (99m)Tc(III) complexes [(99m)TcCl(CDO)(CDOH)2B-R] (CDOH2 = cyclohexanedione dioxime).

    PubMed

    Yang, Yong; Zheng, Yumin; Tomaselli, Elena; Fang, Wei; Liu, Shuang

    2015-02-18

    This study sought to explore the impact of boronate groups on the heart uptake and myocardial retention of novel (99m)Tc(III) complexes [(99m)TcCl(CDO)(CDOH)2B-R] ((99m)Tc-ISboroxime: R = isoxazol-4-yl (IS); (99m)Tc-MPboroxime: R = N-methylpyridinium (MP); (99m)Tc-PAboroxime: R = pyrazol-3-yl (PA); (99m)Tc-PYboroxime: R = pyridin-3-yl (PY); and (99m)Tc-5Uboroxime: R = uracil-5-yl (5U)). All five new (99m)Tc(III) radiotracers were prepared in high yield and high radiochemical purity (RCP = 90-98%), and they remained stable in the kit mixture for >6 h. Biodistribution and imaging (planar and SPECT) studies were carried out using Sprague-Dawley (SD) rats. Planar image quantification was performed to compare their myocardial retention and liver clearance kinetics. It was found that their heart retention and liver clearance curves were best fitted to the biexponential decay function. The initial heart uptake at 0-1 min after injection followed the general ranking order of (99m)Tc-ISboroxime (4.98 ± 1.05%ID) ∼ (99m)Tc-Teboroxime (4.56 ± 0.91%ID) ∼ (99m)Tc-PAboroxime (4.03 ± 1.23%ID) ∼ (99m)Tc-PYboroxime (4.07 ± 0.80%ID) > (99m)Tc-5Uboroxime (3.24 ± 0.67%ID) > (99m)Tc-MPboroxime (2.53 ± 0.65%ID). The fast-phase myocardial retention time followed the general order of (99m)Tc-PAboroxime (3.21 ± 0.29 min) > (99m)Tc-Teboroxime (1.63 ± 0.40 min) ∼ (99m)Tc-PYboroxime (1.57 ± 0.29 min) ∼ (99m)Tc-ISboroxime (1.55 ± 0.32 min) > (99m)Tc-MPboroxime (0.68 ± 0.16 min) > (99m)Tc-5Uboroxime (0.33 ± 0.11 min). (99m)Tc-PAboroxime (3.05 ± 1.10%ID/g) and (99m)Tc-ISboroxime (3.75 ± 0.68%ID/g) had the 2 min initial heart uptake very close to that of (99m)Tc-Teboroxime (3.30 ± 0.50%ID/g). However, the myocardial retention time of (99m)Tc-PAboroxime was significantly longer than that of (99m)Tc-ISboroxime and (99m)Tc-Teboroxime. Even though the best time window is 0-5 min for SPECT image acquisition, high quality SPECT images could be obtained during the first 30 min

  6. [Noninvasive diagnosis of cardiac involvement by technetium-99m-pyrophosphate (Tc-99m PYP) myocardial scintigraphy in 2 cases of familial amyloid polyneuropathy and 1 case of secondary amyloidosis].

    PubMed

    Takezaki, M; Ishida, Y; Morozumi, T; Tani, A; Sato, H; Hori, M; Kitabatake, A; Kamada, T; Kimura, K; Kozuka, T

    1989-12-01

    To validate the significance of technetium-99m-pyrophosphate (Tc-99m PYP) myocardial scintigraphy in diagnosing cardiac amyloidosis, 2 patients with familial amyloid polyneuropathy (FAP) and 1 patient with amyloidosis secondary to chronic rheumatic arthritis were studied. All three patients had echocardiographic abnormalities, which were increased wall thickness of the interventricular septum and the left ventricular posterior wall, and granular sparkling appearance in the septum. In 2 patients with FAP, abnormal myocardial uptake of Tc-99m PYP was diffusely detected in Tc-99m PYP SPECT. In the remaining 1 patient with secondary amyloidosis, however, Tc-99m PYP SPECT showed no abnormality, although we had confirmed the presence of myocardial amyloid deposits (type AA amyloid protein) with high amount in the histological examination. Thus, these results indicate that Tc-99m PYP scintigraphy may have a limitation in detecting cardiac involvement in secondary amyloidosis although it is useful in FAP. PMID:2560088

  7. Tc-99m Labeled carrier for imaging

    DOEpatents

    Henze, Eberhard

    1984-01-01

    Novel radionuclide imaging agents, having particular application for lymphangiography are provided by non-covalently binding Tc-99m to a pharmaceutically acceptable cross-linked polysaccharide. Upon injection of the Tc-99m labeled polysaccharide into the blood stream, optimum contrast can be obtained within one hour.

  8. Cyclotron Production of Technetium-99m

    NASA Astrophysics Data System (ADS)

    Gagnon, Katherine M.

    Technetium-99m (99mTc) has emerged as the most widely used radionuclide in medicine and is currently obtained from a 99Mo/ 99mTc generator system. At present, there are only a handful of ageing reactors worldwide capable of producing large quantities of the parent isotope, 99Mo, and owing to the ever growing shutdown periods for maintenance and repair of these ageing reactors, the reliable supply 99mTc has been compromised in recent years. With an interest in alternative strategies for producing this key medical isotope, this thesis focuses on several technical challenges related to the direct cyclotron production of 99mTc via the 100Mo(p,2n)99mTc reaction. In addition to evaluating the 100Mo(p,2n)99mTc and 100Mo(p,x)99Mo reactions, this work presented the first experimental evaluation of the 100Mo(p,2n) 99gTc excitation function in the range of 8-18 MeV. Thick target calculations suggested that large quantities of cyclotron-produced 99mTc may be possible. For example, a 6 hr irradiation at 500 μA with an energy window of 18→10 MeV is expected to yield 1.15 TBq of 99mTc. The level of coproduced 99gTc contaminant was found to be on par with the current 99Mo/99mTc generator standard eluted with a 24 hr frequency. Highly enriched 100Mo was required as the target material for 99mTc production and a process for recycling of this expensive material is presented. An 87% recovery yield is reported, including metallic target preparation, irradiation, 99mTc extraction, molybdate isolation, and finally hydrogen reduction to the metal. Further improvements are expected with additional optimization experiments. A method for forming structurally stable metallic molybdenum targets has also been developed. These targets are capable of withstanding more than a kilowatt of beam power and the reliable production and extraction of Curie quantities of 99mTc has been demonstrated. With the end-goal of using the cyclotron-produced 99mTc clinically, the quality of the cyclotron

  9. A partial defect in technetium-99m pyrophosphate image suggesting cardiac rupture following acute myocardial infarction.

    PubMed

    Tsujino, M; Hiroe, M; Sugimoto, K; Miyahara, Y; Ishii, Z; Taniguchi, K; Marumo, F

    1992-01-01

    We present the case of a 70-year-old woman with acute myocardial infarction who died of cardiac rupture on the 2nd hospital day. Dual isotope single photon emission computed tomography (SPECT) using thallium-201 chloride and technetium-99m pyrophosphate (PYP) performed on the 2nd hospital day showed a large perfusion defect in the anteroseptal wall on 201Tl image and a increased accumulation on 99mTc-PYP image in the anterior area consistent with a partial defect. Autopsy performed 1 h after death revealed a tear in the left ventricular anterior wall consistent with the defect on the 99mTc-PYP image. We propose that the finding of a partial defect in 99mTc-PYP is an interesting finding which may be associated with cardiac rupture following acute myocardial infarction. PMID:1533369

  10. An Exploratory Study on 99mTc-RGD-BBN Peptide Scintimammography in the Assessment of Breast Malignant Lesions Compared to 99mTc-3P4-RGD2

    PubMed Central

    Chen, Qianqian; Ma, Qingjie; Chen, Minglong; Chen, Bin; Wen, Qiang; Jia, Bing; Wang, Fan; Sun, Butong; Gao, Shi

    2015-01-01

    Purpose This study aimed to explore the diagnostic performance of single photon emission computed tomography / computerized tomography (SPECT/CT) using a new radiotracer 99mTc-RGD-BBN for breast malignant tumor compared with 99mTc-3P4-RGD2. Methods 6 female patients with breast malignant tumors diagnosed by fine needle aspiration cytology biopsy (FNAB) who were scheduled to undergo surgery were included in the study. 99mTc-3P4-RGD2 and 99mTc-RGD-BBN were performed with single photon emission computed tomography (SPECT) at 1 hour after intravenous injection of 299 ± 30 MBq and 293 ± 32 MBq of radiotracers respectively at separate day. The results were evaluated by the Tumor to non-Tumor ratios (T/NT). 99mTc-RGD-BBN and 99mTc-3P4-RGD2 SPECT/CT images were interpreted independently by 3 experienced nuclear medicine physicians using a 3-point scale system. All of the samples were analyzed immunohistochemically to evaluate the integrin αvβ3 and gastrin-releasing peptide receptor (GRPR) expression. The safety, biodistribution and radiation dosimetry of 99mTc-RGD-BBN were also evaluated in the healthy volunteers. Results No serious adverse events were reported in any of the patients during the study. The effective radiation dose entirely conformed to the relevant standards. A total of 6 palpable malignant lesions were detected using 99mTc-RGD-BBN SPECT/CT with clear uptake. All malignant lesions were also detected using 99mTc-3P4-RGD2 SPECT/CT. The results showed that five malignant lesions were with clear uptake and the other one with barely an uptake. 4 malignant cases were found with both αvβ3 and GRPR expression, 1 case with only GRPR positive expression (integrin αvβ3 negative) and 1 case with only integrin αvβ3 positive expression (GRPR negative). Conclusion 99mTc-RGD-BBN is a safe agent for detecting breast cancer. 99mTc-RGD-BBN may have the potential to make up for the deficiency of 99mTc-3P4-RGD2 in the detection of breast cancer with only GRPR positive

  11. Regional brain uptake and retention of Tc-99m-propylene amine oxime derivatives

    SciTech Connect

    Chaplin, S.B.; Oberle, P.O.; Hoffman, T.J.; Volkert, W.A.; Holmes, R.A.; Nowotnik, D.P.; Pickett, R.D.; Neirinckx, R.

    1985-05-01

    Tc-99m-propylene amine oxime (Tc-99m-PnAO) is a neutral lipophilic chelate that rapidly and passively enters the cerebral cortex (80% on first pass in baboon brain) and then clears exponentially leaving inadequate activity to perform conventional SPECT brain imaging. When side chains are attached to the PnAO backbone lipophilicity is increased, as well as brain retention. In this work the authors evaluated regional brain uptake and retention of Tc-99m-PnAO and several of its derivatives in rat brain using serial autoradiography (ARG). Autoradiographs of each Tc-99m chelate at 5 sec. post peak brain uptake demonstrate discrete grey to white matter differentiation. White matter tracts are well delineated and the darker areas of grey matter appearing in the midbrain and thalamus, corresponding to areas of high capillary density and high blood flow documented with C-14-iodoantipyrine, are easily distinguished. Within 5 min. of the peak uptake the regional uptake and grey/white differentiation is lost on the Tc-99m-PnAO ARG. In contrast the 5 min. ARG of the more lipophilic Tc-99m, chelate with dimethyl-PnAO (DMPnAO) shows the complete reverse of the 5 sec. ARG, with greater activity in the white matter tracts than in the grey matter. One of the derivatives, tetramethyl-PAO (TMPAO) complexed with Tc-99m is retained in the grey matter of rat brain and shows persistent grey to white localization for at least 60 min., analogous to what has been reported with I-123-IMP. These results suggest that Tc-99m-TMPAO or one of its derivatives may be appropriate for SPECT imaging of cerebral blood flow abnormalities.

  12. The functional hepatic volume assessed by 99mTc-GSA hepatic scintigraphy.

    PubMed

    Wu, J; Ishikawa, N; Takeda, T; Tanaka, Y; Pan, X Q; Sato, M; Todoroki, T; Hatakeyama, R; Itai, Y

    1995-11-01

    The accuracy of measurement of the functional hepatic volume by single photon emission computed tomography (SPECT) with 99mTc-galactosyl serum albumin (99mTc-GAS) was evaluated. 99mTc-GSA planar scintigraphic images were obtained dynamically and the hepatic SPECT imaging was then performed in 25 patients with hepatobiliary tumors. The patients were divided into 4 groups with normal hepatic function, and mild, moderate and severe hepatic dysfunction. The functional hepatic volume determined by SPECT was compared with the morphological hepatic volume determined by compute tomography. The ratio of the hepatic volumes obtained by the two methods was calculated. The mean hepatic volume ratio was 96.6 +/- 2.3% in the normal hepatic function group and 95.9 +/- 2.2% in the mild dysfunction group (n.s.). In both the moderate and severe hepatic dysfunction groups, the hepatic volume ratio was smaller than that in the normal group (87.9 +/- 5.2%, p < 0.0001, and 71.9 +/- 7.6%, p < 0.0001, respectively). There was a linear correlation between the hepatic volume ration and various indices of reserve hepatic function, such as LHL15 (r = 0.83, p < 0.0001), HH15(r = 0.74, p < 0.0001), and ICG15 (r = 0.75, p < 0.0005). These results indicate that the hepatic volume ratio is proportional to the severity of hepatic dysfunction, and suggest that the functional hepatic volume measured with 99mTc-GSA faithfully reflects the functioning hepatocyte mass. 99mTc-GSA scintigraphy and hepatic SPECT therefore provide information regarding global and regional reserve hepatic function. PMID:8770291

  13. Preparation and Biodistribution of Technetium-99m-Labeled Bis- Misonidazole (MISO) as an Imaging Agent for Tumour Hypoxia.

    PubMed

    Wang, Feng; Fan, Di; Qian, Jun; Zhang, Zhe; Zhu, Jianhua; Chen, Jian

    2015-01-01

    Diagnosis of tumour hypoxia is an important aspect in determining the course of tumour therapy. In this study, we developed a novel imaging agent, (99m)Tc-ethylenedicysteine-bis-misonidazole ((99m)Tc-EC-MISO), for diagnosing tumour hypoxia. We used 2-nitroimidazole as a reactant to synthesize the amino derivative of misonidazole (MISO) in the first step and then conjugated the di-amino derivative of MISO to the chelating agent ethylenedicysteine (EC) for labelling (99m)Tc in the second step. (99m)Tc-pertechnetate ((99m)TcO4-) was reduced by tin chloride (SnCl2) for radiolabeling. The radiochemical purity was up to 94%. Tissue biodistribution and SPECT/CT imaging studies were conducted on subcutaneous gliomal tumour-bearing mice. The tumour-to-muscle ratio in the (99m)Tc-EC-MISO group increased with time, up to 4.6 at 4 h after injection. SPECT/CT imaging confirmed that the tumours could be visualized clearly with (99m)Tc-EC-MISO at 2 h. By introducing a second 2-nitroimidazole redox centre, an apparent hypoxic accumulation of this novel (99m)Tc-labeled imaging agent in the tumour was observed. PMID:25938423

  14. [Imaging of hyperparathyroidism-Ultrasonography and 99mTc-MIBI scintigraphy-].

    PubMed

    Kawabe, Joji; Higashiyama, Shigeaki; Yoshida, Atsushi; Kotani, Kohei; Shiomi, Susumu

    2016-06-01

    Treatments for primary hyperparathyroidism due to adenoma, hyperplasia and carcinoma and secondary hyperparathyroidism are mainly surgical resections of them. Accurate imaging diagnoses of the existences and the regions are very important for reductions of invasiveness. We describe ultrasonography and 99mTc-MIBI scintigraphy of hyperparathyroidism. We explain an advantage, a disadvantage and diagnosability of these modalities. We mention utilities of SPECT/CT, too. We show echogram and 99mTc-MIBI scintigraphy images about 3 cases of hyperparathyroidism. PMID:27230842

  15. Utility of (99m)Tc RBC Scintigraphy in Diagnosing Parotid Venous Malformations.

    PubMed

    Patel, Rosan; Saad, Hannan; Srinivasan, Ashok; Brown, Richard K J

    2015-07-01

    Venous malformations of the parotid glands are uncommon and can be difficult to confirm on routine anatomical imaging alone because of overlap of imaging features with other more common parotid lesions. (99m)Tc RBC scans combined with SPECT/CT offer a noninvasive way to diagnose parotid venous malformations without the need for biopsy. Combined with anatomical findings of phleboliths (when present), the diagnosis can be reliably determined. We present a case where MRI and biopsy were inconclusive, but the SPECT/CT was used to confirm the suspicion of a benign venous malformation. PMID:26018710

  16. Synthesis and Evaluation of (99m)Tc-Labeled Dimeric Folic Acid for FR-Targeting.

    PubMed

    Guo, Zhide; Gao, Mengna; Song, Manli; Shi, Changrong; Zhang, Pu; Xu, Duo; You, Linyi; Zhuang, Rongqiang; Su, Xinhui; Liu, Ting; Du, Jin; Zhang, Xianzhong

    2016-01-01

    The folate receptor (FR) is overexpressed in a wide variety of human tumors. In our study, the multimeric concept was used to synthesize a dimeric folate derivative via a click reaction. The novel folate derivative (HYNIC-D₁-FA₂) was radiolabeled with (99m)Tc using tricine and trisodium triphenylphosphine-3,3',3″-trisulfonate (TPPTS) as coligands ((99m)Tc-HYNIC-D₁-FA₂) and its in vitro physicochemical properties, ex vivo biodistribution and in vivo micro-SPECT/CT imaging as a potential FR targeted agent were evaluated. It is a hydrophilic compound (log P = -2.52 ± 0.13) with high binding affinity (IC50 = 19.06 nM). Biodistribution in KB tumor-bearing mice showed that (99m)Tc-HYNIC-D₁-FA₂ had high uptake in FR overexpressed tumor and kidney at all time-points, and both of them could obviously be inhibited when blocking with free FA in the blocking studies. From the in vivo micro-SPECT/CT imaging results, good tumor uptake of (99m)Tc-HYNIC-D₁-FA₂ was observed in KB tumor-bearing mice and it could be blocked obviously. Based on the results, this new radiolabeled dimeric FA tracer might be a promising candidate for FR-targeting imaging with high affinity and selectivity. PMID:27338334

  17. Radiopharmaceuticals for SPECT Cancer Detection

    NASA Astrophysics Data System (ADS)

    Chernov, V. I.; Medvedeva, A. A.; Zelchan, R. V.; Sinilkin, I. G.; Stasyuk, E. S.; Larionova, L. A.; Slonimskaya, E. M.; Choynzonov, E. L.

    2016-06-01

    The purpose of the study was to assess the efficacy of single photon emission computed tomography (SPECT) with 199Tl and 99mTc-MIBI in the detection of breast, laryngeal and hypopharyngeal cancers. Materials and Methods: a total of 220 patients were included into the study. Of them, there were 120 patients with breast lesions (100 patients with breast cancer and 20 patients with benign breast tumors) and '00 patients with laryngeal/hypopharyngeal diseases (80 patients with laryngeal/hypopharyngeal cancer and 20 patients with benign laryngeal/hypopharyngeal lesions). Results: no abnormal 199Tl uptake was seen in all patients with benign breast and laryngeal lesions, indicating a 100% specificity of 199Tl SPECT. In breast cancer patients, increased 199Tl uptake in the breast was visualized in 94.8% patients, 99mTc-MIBI in 93.4% patients. Increased 199Tl uptake in axillary lymph nodes was detected in 60% patients and 99mTc-MIBI in 93.1% patients. In patients with laryngeal/hypopharyngeal cancer, sensitivity of SPECT with 199Tl and 99mTc-MIBI were 95%. The 199Tl SPECT sensitivity in identification of regional lymph node metastases in patients with laryngeal/hypopharyngeal cancer was 75% and the 99mTc-MIBI SPECT sensitivity was 17%. Conclusion: the data obtained show that SPECT with 199Tl and 99mTc-MIBI can be used as one of the additional imaging methods in detection of tumors.

  18. Radiopharmaceuticals for SPECT cancer detection

    NASA Astrophysics Data System (ADS)

    Chernov, V. I.; Medvedeva, A. A.; Zelchan, R. V.; Sinilkin, I. G.; Stasyuk, E. S.; Larionova, L. A.; Slonimskaya, E. M.; Choynzonov, E. L.

    2016-08-01

    The purpose of the study was to assess the efficacy of single photon emission computed tomography (SPECT) with 199Tl and 99mTc-MIBI in the detection of breast, laryngeal and hypopharyngeal cancers. A total of 220 patients were included into the study: 120 patients with breast lesions (100 patients with breast cancer and 20 patients with benign breast tumors) and 100 patients with laryngeal/hypopharyngeal diseases (80 patients with laryngeal/hypopharyngeal cancer and 20 patients with benign laryngeal/hypopharyngeal lesions). No abnormal 199Tl uptake was seen in all patients with benign breast and laryngeal lesions, indicating a 100% specificity of 199Tl SPECT. In the breast cancer patients, the increased 199Tl uptake in the breast was visualized in 94.8% patients, 99mTc-MIBI—in 93.4% patients. The increased 199Tl uptake in axillary lymph nodes was detected in 60% patients, and 99mTc-MIBI—in 93.1% patients. In patients with laryngeal/hypopharyngeal cancer, the sensitivity of SPECT with 199Tl and 99mTc-MIBI was 95%. The 199Tl SPECT sensitivity in identification of regional lymph node metastases in the patients with laryngeal/hypopharyngeal cancer was 75% and the 99mTc-MIBI SPECT sensitivity was 17%. The data obtained showed that SPECT with 199Tl and 99mTc-MIBI can be used as one of the additional imaging methods in detection of tumors.

  19. Biodistribution and pharmacokinetics of the (99m)Tc labeled human elastase inhibitor, elafin, in rats.

    PubMed

    Kaschwich, Mark; Lützen, Ulf; Zhao, Yi; Tjiong, Angelina; Marx, Marlies; Haenisch, Sierk; Wiedow, Oliver; Preuss, Stefanie; Culman, Juraj; Zuhayra, Maaz

    2016-04-01

    Elafin is a potent reversible inhibitor of the pro-inflammatory proteases leukocyte elastase and protease 3. It is currently in clinical development for the use in postoperative inflammatory diseases. We investigated the pharmacokinetics of (99m)Tc-labeled elafin ((99m)Tc-Elafin) in blood and individual organs in rat after bolus intravenous injection using the single photon emission tomography (SPECT). (99m)Tc-Elafin predominantly accumulated in the kidney reaching a maximum of 8.5% ± 0.1% of the injected dose per gram (ID/g) at 5 min post injection (p.i) and decreased only slowly during 24 h. In contrast, the initially high radio activity recorded in the other organs rapidly decreased parallel to the radioactivity detected in blood. The blood kinetics fits to a two compartment kinetics model. The radio activity in the dissected kidney was 4.98 ± 1.24%ID/g 24 h p.i, while in other organs, including the brain, no accumulation of (99m)Tc-Elafin was detected. At this time point 30% of the detected radioactivity in the kidney was identified to be not metabolized (99m)Tc-Elafin. In conclusion, the blood and organ-specific kinetic data provide a basis for planning of adequate dosing regimens and the high accumulation of intact elafin in the kidney favors clinical developments targeting inflammatory kidney diseases, such as chronic allograft nephropathy after kidney transplantation. PMID:26948953

  20. Evaluation of 99mTcN-MPO as a New Myocardial Perfusion Imaging Agent in Normal Dogs and in an Acute Myocardial Infarction Canine Model: Comparison with 99mTc-Sestamibi

    PubMed Central

    Bu, Lihong; Li, Renfei; Jin, Zhongnan; Wen, Xiaofei; Liu, Shuang; Yang, Baofeng; Shen, Baozhong; Chen, Xiaoyuan

    2010-01-01

    Purpose 99mTcN-MPO ([99mTcN(mpo)(PNP5)]+: mpo=2-mercaptopyridine oxide and PNP5=N-ethoxyethyl-N,N-bis[2-(bis(3-methoxypropyl)phosphino)ethyl]amine) is a cationic 99mTc-nitrido complex, which has favorable biodistribution and myocardial uptake with rapid liver clearance in Sprague Dawley rats. The objective of this study was to compare the biodistribution and pharmacokinetics of 99mTcN-MPO and 99mTc-Sestamibi in normal dogs, and to evaluate the potential of 99mTcN-MPO as a myocardial perfusion agent in canines with acute myocardial infarction. Methods Five normal mongrel dogs were injected intravenously with 99mTcN-MPO. Venous blood samples were collected via a femoral vein catheter at 0.5, 1, 2, 3, 4, 5, 10, 20, 30, 40, 60, and 90 min post-injection (p.i.). Anterior-posterior planar images were acquired by γ-camera at 10, 20, 30, 60, 90, and 120 min p.i. Regions of interest (ROIs) were drawn around the heart, liver, and lungs. The heart/liver and heart/lung ratios were calculated by dividing the mean counts in heart ROI by the mean counts in the liver and lung ROI, respectively. For comparison, 99mTc-sestamibi was also evaluated in the same five dogs. The interval period between the two examinations was 1 week to eliminate possible interference between these two radiotracers. In addition, single positron emission computed tomography (SPECT) images in the canine infarct model were collected 24 h after myocardial infarction at 30 and 60 min after the administration of 99mTcN-MPO (n=4) or 99mTc-Sestamibi (n=4). Results It was found that 99mTcN-MPO and 99mTc-Sestamibi displayed very similar blood clearance characteristics during the first 90 min p.i. Both 99mTcN-MPO and 99mTc-Sestamibi had a rapid blood clearance with less than 50% of initial radioactivity remaining at 1 min and less than 5% at 30 min p.i. 99mTcN-MPO and 99mTc-Sestamibi both showed good heart/lung contrast. The heart/liver ratio of 99mTcN-MPO increased with time (0.53±0.06 at 10 min, 0.90±0.062 at

  1. SPECT imaging in a case of primary respiratory tract amyloidosis.

    PubMed

    Nishihara, M; Oda, J; Kamura, T; Kimura, M; Odano, I; Sakai, K

    1993-08-01

    SPECT findings in a very rare case of primary amyloidosis localized in the laryngotracheobronchial area are reported. SPECT using Tc-99m PYP revealed widespread uptake in the larynx and the entire tracheobronchial tree up to the subsegmental divisions; the areas corresponded to diffuse thickening and calcification of the walls on CT. SPECT using Ga-67 citrate also showed marked uptake in the same area, consistent with the findings shown by SPECT using Tc-99m PYP. PMID:8403700

  2. The use of 99mTc-Al2O3 for detection of sentinel lymph nodes in breast cancer

    NASA Astrophysics Data System (ADS)

    Sinilkin, I.; Chernov, V.; Medvedeva, A.; Zeltchan, R.; Slonimskaya, E.; Doroshenko, A.; Varlamova, N.; Skuridin, V.

    2016-08-01

    Purpose: to study the feasibility of using the new radiopharmaceutical based on the technetium-99m-labeled gamma-alumina for identification of sentinel lymph nodes (SLNs) in breast cancer patients. The study included two groups of breast cancer patients who underwent single photon emission computed tomography (SPECT) and intraoperaive gamma probe identification of sentinel lymph nodes (SLNs). To identify SLNs, the day before surgery Group I patients (n = 34) were injected with radioactive 99mTc-Al2O3, and Group II patients (n = 30) received 99mTc-labeled phytate colloid. A total of 37 SLNs were detected in Group I patients. The number of identified SLNs per patient ranged from 1 to 2 (the average number of identified SLNs was 1.08). Axillary lymph nodes were the most common site of SLN localization. 18 hours after 99mTc-Al2O3 injection, the percentage of its accumulation in the SLN was 7-11% (of the counts in the injection site) by SPECT and 17-31% by gamma probe detection. In Group II SLNs were detected in 27 patients. 18 hours after injection of the phytate colloid the percentage of its accumulation in the SLN was 1.5-2% out of the counts in the injection site by SPECT and 4-7% by gamma probe. The new radiopharmaceutical based on the 99mTc-Al2O3 demonstrates high accumulation in SLNs without redistribution through the entire lymphatic basin. The sensitivity and specificity of 99mTc-Al2O3 were 100% for both SPECT and intraoperative gamma probe identification.

  3. 99mTC-Methylene diphosphonate uptake at injury site correlates with osteoblast differentiation and mineralization during bone healing in mice

    PubMed Central

    Zhong, Zhendong A; Peck, Anderson; Li, Shihong; VanOss, Jeff; Snider, John; Droscha, Casey J; Chang, Tingtung A; Williams, Bart O

    2015-01-01

    99mTc-Methylene diphosphonate (99mTc-MDP) is widely used in clinical settings to detect bone abnormalities. However, the mechanism of 99mTc-MDP uptake in bone is not well elucidated. In this study, we utilized a mouse tibia injury model, single-photon emission computed tomography (gamma scintigraphy or SPECT), ex vivo micro-computed tomography, and histology to monitor 99mTc-MDP uptake in injury sites during skeletal healing. In an ex vivo culture system, calvarial cells were differentiated into osteoblasts with osteogenic medium, pulsed with 99mTc-MDP at different time points, and quantitated for 99mTc-MDP uptake with a gamma counter. We demonstrated that 99mTc-MDP uptake in the injury sites corresponded to osteoblast generation in those sites throughout the healing process. The 99mTc-MDP uptake within the injury sites peaked on day 7 post-injury, while the injury sites were occupied by mature osteoblasts also starting from day 7. 99mTc-MDP uptake started to decrease 14 days post-surgery, when we observed the highest level of bony tissue in the injury sites. We also found that 99mTc-MDP uptake was associated with osteoblast maturation and mineralization in vitro. This study provides direct and biological evidence for 99mTc-MDP uptake in osteoblasts during bone healing in vivo and in vitro. PMID:26273540

  4. Soft-tissue uptake of 99mTc-diphosphonate and 99mTc-pyrophosphate in amyloidosis.

    PubMed

    Janssen, S; Piers, D A; van Rijswijk, M H; Meijer, S; Mandema, E

    1990-01-01

    This study describes the results of scintigraphy with 99mTc-labeled methylene-diphosphonate (99mTc-MDP) and pyrophosphate (99mTc-PYP) as a noninvasive test for the distribution of organ involvement in five different types of amyloidosis. Scintigraphy with 99mTc-labeled phosphates appeared to be a sensitive noninvasive screening test for the extent and the distribution of organ involvement in systemic AA and systemic AL amyloidosis as well as in local bronchial amyloid, local dermal amyloid, and familial amyloidotic polyneuropathy. Echocardiography, however, was more sensitive for demonstrating cardiac involvement in systemic amyloidosis than 99mTc-MDP or 99mTc-PYP scintigraphy. 99mTc-MDP images showed a better contrast than 99mTc-PYP images, although there was no difference in the extent or the intensity of soft-tissue uptake. PMID:2166666

  5. (99m)Tc-bioorthogonal click chemistry reagent for in vivo pretargeted imaging.

    PubMed

    García, María Fernanda; Zhang, Xiuli; Shah, Manankumar; Newton-Northup, Jessica; Cabral, Pablo; Cerecetto, Hugo; Quinn, Thomas

    2016-03-15

    Metal-free click chemistry has become an important tool for pretargeted approaches in the molecular imaging field. The application of bioorthogonal click chemistry between a pretargeted trans-cyclooctene (TCO) derivatized monoclonal antibody (mAb) and a (99m)Tc-modified 1,2,4,5-tetrazine for tumor imaging was examined in vitro and in vivo. The HYNIC tetrazine compound was synthesized and structurally characterized, confirming its identity. Radiolabeling studies demonstrated that the HYNIC tetrazine was labeled with (99m)Tc at an efficiency of >95% and was radiochemically stable. (99m)Tc-HYNIC tetrazine reacted with the TCO-CC49 mAb in vitro demonstrating its selective reactivity. In vivo biodistribution studies revealed non-specific liver and GI uptake due to the hydrophobic property of the compound, however pretargeted SPECT imaging studies demonstrated tumor visualization confirming the success of the cycloaddition reaction in vivo. These results demonstrated the potential of (99m)Tc-HYNIC-tetrazine for tumor imaging with pretargeted mAbs. PMID:26875936

  6. [Marked 99mTc-PYP myocardial accumulation immediately after reperfusion in a patient with acute myocardial infarction].

    PubMed

    Adachi, Yoshihiko; Ito, Kazuki; Nishikawa, Susumu; Yuba, Tatsuya; Tsubakimoto, Yoshinori; Takata, Hiroki; Kato, Shuji; Azuma, Akihiro; Sugihara, Hiroki; Nakagawa, Masao

    2003-02-01

    We reported a case of a 72-year-old man with chest pain. An electrocardiogram showed ST segment elevation in I, II, III, aVL, aVF and V1-6 leads. 99mTc-tetrofosmin myocardial SPECT showed defect in the anterior, septal, apical and inferior walls. Coronary angiography showed 99% stenosis of the proximal right coronary artery and total occlusion of the midsegment of the left anterior descending coronary artery. Therefore, direct PTCA was performed for each lesion to achieve reperfusion. We didnt's see reperfusion injury during PTCA of the left coronary artery. On the other side, we saw severe reperfusion injury, such as slow-flow, arrhythmia and falling blood pressure during PTCA of the right coronary artery. After four hours, 99mTc-PYP myocardial SPECT showed marked uptake in the apical and inferior walls, and mild uptake in the anterior and posterior walls. After three days, severely-reduced uptake of 99mTc-PYP in the apex was noted, and mild uptake in the mid-portion of the anterior wall and the mid-portion of the inferior wall. Though reperfusion injury was seen, three was mild myocardial uptake of 99mTc-PYP in the area of the right coronary artery. On the other side, despite no reperfusion injury, there showed marked uptake during the acute phase and defect during the subacute phase in the area of the left coronary artery. Wall motion of the left ventricle was normal in the area of the right coronary artery and akinesis was seen on the left. These findings suggest that 99mTc-tetrofosmin and 99mTc-PYP myocardial SPECT are useful for visualization of reperfusion injury during the acute phase and for estimation of function during the chronic phase, better even than electrocardiogram or coronary angiography. PMID:12701202

  7. Retention of 99mTc-DMSA(III) and 99mTc-nanocolloid in different syringes affects imaging quality.

    PubMed

    Bauwens, Matthias; Pooters, Ivo; van der Pol, Jochen; Mottaghy, Felix M; van Kroonenburgh, Marinus

    2014-04-01

    (99m)Tc-dimercaptosuccinic acid [DMSA(III)] and colloidal human serum albumin ((99m)Tc-nanocolloid) are widely used radiopharmaceuticals. Recently, in our institution we encountered image quality problems in DMSA scans after changing the brand of syringes we were using, which triggered us to look into the adsorption properties of syringes from different brands for (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid. We also describe a clinical case in which adsorption of (99m)Tc-DMSA(III) caused inferior imaging quality. DMSA and nanocolloid were labeled with (99m)Tc following manufacturer guidelines. After synthesis, syringes with (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid were stored for 15, 30, 60, and 120 min. We evaluated Luer Lock syringes manufactured by different brands such as Artsana, Henke-Sass-Wolf, B. Braun Medical N.V., CODAN Medizinische Geräte GmbH & Co KG, Becton Dickinson and Company, and Terumo Europe. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid was acceptably low for all syringes (<13%), except for two brands with (99m)Tc-DMSA(III) adsorption rates of 36 and 30%, respectively, and for one brand with a (99m)Tc-nanocolloid adsorption rate of 27%. Adsorption of (99m)Tc-DMSA(III) and (99m)Tc-nanocolloid reaches critical levels in syringes produced by two brands, potentially causing poor image quality--for example, in DMSA scans using pediatric radiopharmaceutical doses. It is advised to check the compatibility of any radiopharmaceutical with syringes as an integral part of the quality assurance program. PMID:24569706

  8. Pharmacokinetics of the phosphatidylserine tracers 99mTc-lactadherin and 99mTc-annexin V in pigs

    PubMed Central

    2013-01-01

    Background Phosphatidylserine (PS) is a phospholipid normally located in the inner leaflet of the cell membrane. PS is translocated from the inner to the outer leaflet of the plasma membrane during the early stages of apoptosis and in necrosis. In cell and animal studies, reversible PS externalisation to the outer membrane leaflet has been observed in viable cells. Hence, PS markers have been proposed as markers of both reversibly and irreversibly damaged cells. The purpose of this experimental study in pigs was to investigate the kinetics of the newly introduced PS marker technetium-99m-labelled lactadherin (99mTc-lactadherin) in comparison with the well-known PS tracer 99mTc-annexin V with special reference to the renal handling of the tracers. The effective dose for humans was estimated from the biodistribution in 24 mice. Methods Nine anaesthetised pigs randomly allocated into two treatment groups were administered a single injection of either 99mTc-lactadherin or 99mTc-annexin V. Renal perfusion was assessed by simultaneous injection of 51Cr-EDTA. Throughout the examinations, planar, dynamic scintigraphy of the trunk was performed, urine was collected and arterial and renal vein blood was sampled. The effective dose was estimated using the adult male phantom from the RADAR website. Results 99mTc-lactadherin was cleared four times faster from plasma than 99mTc-annexin V, 57 ± 13 ml/min (mean ± SD) versus 14 ± 2 ml/min. 99mTc-lactadherin had a predominant uptake in the liver, whereas 99mTc-annexin V was primarily taken up by the kidneys. The estimated effective human dose after single injection of 99mTc-lactadherin and 99mTc-annexin V was 5.8 and 11 μSv/MBq, respectively. Conclusions The high hepatic uptake of 99mTc-lactadherin compromises the use of 99mTc-lactadherin for imaging PS externalisation in the liver. Due to scatter from the liver, the use of in vivo visualisation of PS externalisation in the lower thorax and upper abdomen by 99m

  9. Evaluation of Technetium-99m glucoheptonate single photon emission computed tomography for brain tumor grading

    PubMed Central

    Alam, Syed Shafiq; Junaid, Syed; Ahmed, Syed Mushtaq

    2016-01-01

    Background: This study is designed to appraise the diagnostic value of technetium-99m glucoheptonate (Tc-99m GHA) single photon emission computed tomography (SPECT) in brain tumor grading. Subjects and Methods: The study was performed on 30 patients referred from the Department of Neurosurgery, who were from both urban and rural areas. Data were collected through interview, history taking, and clinical examination followed by recording the desired parameters and finally imaging. The study subjects were divided into five groups: Controls (n = 4), low-grade tumors (n = 8), high-grade tumors (n = 8), metastases (n = 5), and nonneoplastic lesions (n = 5). This division was based on the World Health Organization (WHO) classification postclinico-histological diagnosis. Each of the subjects underwent contrast-enhanced computed tomography/contrast-enhanced magnetic resonance and Tc-99m GHA SPECT preoperatively. All were followed up postoperatively, and histopathological reports were regarded as the gold standard for tumor grading wherever available. Results: It was found that high-grade tumors (Grades III/IV and IV/IV according to the WHO classification) showed significantly higher tumor to normal (T/N) ratios as well as Tmax/N ratios when compared with low-grade tumors (Grades I/IV and II/IV), metastases or nonneoplastic lesions. Conclusions: In summary, the results of this study suggest that in situations where a preoperative grading of tumor is required Tc-99m GHA can be used in tumor grading and its use should be encouraged. Semi-quantitative analysis using both T/N as well as Tmax/N can be used in differentiating high-grade tumors from low-grade ones. PMID:27057217

  10. Clinical experience with technetium-99m teboroxime, a neutral, lipophilic myocardial perfusion imaging agent

    SciTech Connect

    Johnson, L.L.; Seldin, D.W. )

    1990-10-16

    Technetium-99m (Tc-99m) teboroxime is a new technetium-based myocardial perfusion imaging agent (investigational code = SQ30217 (Cardiotec, Squibb Diagnostics)). A member of a class of neutral, lipophilic, technetium-containing complexes known as boronic acid adducts of technetium dioxime (BATO) complexes, this agent is chemically very different from the cationic tracer thallium-201 (Tl-201) and from the cationic technetium complex Tc-99m sestamibi (Cardiolite, Du Pont Imaging Agents). Tc-99m teboroxime has high myocardial extraction, rapid blood clearance, little lung uptake and rapid myocardial washout. A biexponential pattern of myocardial washout is demonstrated in animals and in man. Effective half-lives of the 2 washout components in man are 5.2 minutes and 3.8 hours and represent approximately 66 and 33% of the myocardial activity, respectively. The first half-life for the myocardium is approximately 11 minutes. As the agent washes out of the heart, hepatic uptake occurs, peaking at about 5 minutes after injection. The liver is the major organ of excretion and receives, along with the large bowel, the largest radiation dose. Rapid imaging protocols using standard cameras have achieved good myocardial counts from 3 planar views acquired over a 4- to 5-minute period or for single photon emission computed tomography (SPECT) images acquired over a 10-minute period. An entire stress/rest procedure can be completed in 1 hour. Analysis of data from 155 patients from 4 centers using planar or SPECT imaging showed a sensitivity and specificity for blinded readings of 82 and 91%, respectively, when compared against overall clinical impression. 13 references.

  11. 99mTc radiolabelling of Fe3O4-Au core-shell and Au-Fe3O4 dumbbell-like nanoparticles

    NASA Astrophysics Data System (ADS)

    Felber, M.; Alberto, R.

    2015-04-01

    The development of nanoparticle-based dual-modality probes for magnetic resonance imaging (MRI) and positron emission tomography (PET) or single photon emission computed tomography (SPECT) is increasingly growing in importance. One of the most commonly used radionuclides for clinical SPECT imaging is 99mTc and the labelling of Fe3O4 nanoparticles with 99mTc was shown to be a successful strategy to obtain dual-modality imaging agents. In this work, we focus on gold containing magnetic nanomaterials. The radiolabelling of magnetic Fe3O4-Au core-shell and Fe3O4-Au dumbbell-like nanoparticles with the [99mTc(CO)3]+ fragment is described. The key elements for this 99mTc labelling approach are novel coating ligands, consisting of an anchor for the Au surface, a polyethylene glycol linker and a strong chelator for the [99mTc(CO)3]+ moiety.The development of nanoparticle-based dual-modality probes for magnetic resonance imaging (MRI) and positron emission tomography (PET) or single photon emission computed tomography (SPECT) is increasingly growing in importance. One of the most commonly used radionuclides for clinical SPECT imaging is 99mTc and the labelling of Fe3O4 nanoparticles with 99mTc was shown to be a successful strategy to obtain dual-modality imaging agents. In this work, we focus on gold containing magnetic nanomaterials. The radiolabelling of magnetic Fe3O4-Au core-shell and Fe3O4-Au dumbbell-like nanoparticles with the [99mTc(CO)3]+ fragment is described. The key elements for this 99mTc labelling approach are novel coating ligands, consisting of an anchor for the Au surface, a polyethylene glycol linker and a strong chelator for the [99mTc(CO)3]+ moiety. Electronic supplementary information (ESI) available: Analyses of Fe3O4-Au core-shell nanoparticles; analyses of Au-Fe3O4 dumbbell-like nanoparticles; 99mTc labelling of Fe3O4-Au core-shell nanoparticles; 99mTc complexes; 99mTc labelling of Au-Fe3O4 dumbbell-like nanoparticles; syntheses coating ligands. See

  12. 99mTc-ciprofloxacin for diagnosis of bacterial infection

    NASA Astrophysics Data System (ADS)

    Aungurarat, A.; Ngamprayad, T.; Dangprasert, M.; Phumkem, S.; Jowanaridhi, B.

    2015-05-01

    Preparation of 99mTc-ciprofloxacin for diagnosis of bacterial infection was investigated by varying factors which affected this compound. The optimum conditions for preparation of 99mTc-ciprofloxacin and a lyophilized kit for Tc-99m labelling were studied. The results from biodistribution study showed that the percentages of the injected dose per gram tissues of infected area at 1 and 3 hours after injection were around 0.25-0.56. 99mTc-ciprofloxacin was found sterile, pyrogen-free and non-toxic. Radiochemical purity was greater than 90% with greater than 6 hours of stability.

  13. 99mTc Labeled Glucagon-Like Peptide-1-Analogue (99mTc-GLP1) Scintigraphy in the Management of Patients with Occult Insulinoma

    PubMed Central

    Sowa-Staszczak, Anna; Trofimiuk-Müldner, Małgorzata; Stefańska, Agnieszka; Tomaszuk, Monika; Buziak-Bereza, Monika; Gilis-Januszewska, Aleksandra; Jabrocka-Hybel, Agata; Głowa, Bogusław; Małecki, Maciej; Bednarczuk, Tomasz; Kamiński, Grzegorz; Kowalska, Aldona; Mikołajczak, Renata; Janota, Barbara; Hubalewska-Dydejczyk, Alicja

    2016-01-01

    Introduction The aim of this study was to assess the utility of [Lys40(Ahx-HYNIC-99mTc/EDDA)NH2]-exendin-4 scintigraphy in the management of patients with hypoglycemia, particularly in the detection of occult insulinoma. Materials and Methods Forty patients with hypoglycemia and increased/confusing results of serum insulin and C-peptide concentration and negative/inconclusive results of other imaging examinations were enrolled in the study. In all patients GLP-1 receptor imaging was performed to localise potential pancreatic lesions. Results Positive results of GLP-1 scintigraphy were observed in 28 patients. In 18 patients postsurgical histopathological examination confirmed diagnosis of insulinoma. Two patients had contraindications to the surgery, one patient did not want to be operated. One patient, who presented with postprandial hypoglycemia, with positive result of GLP-1 imaging was not qualified for surgery and is in the observational group. Eight patients were lost for follow up, among them 6 patients with positive GLP-1 scintigraphy result. One patient with negative scintigraphy was diagnosed with malignant insulinoma. In two patients with negative scintigraphy Munchausen syndrome was diagnosed (patients were taking insulin). Other seven patients with negative results of 99mTcGLP-1 scintigraphy and postprandial hypoglycemia with C-peptide and insulin levels within the limits of normal ranges are in the observational group. We would like to mention that 99mTc-GLP1-SPECT/CT was also performed in 3 pts with nesidioblastosis (revealing diffuse tracer uptake in two and a focal lesion in one case) and in two patients with malignant insulinoma (with the a focal uptake in the localization of a removed pancreatic headin one case and negative GLP-1 1 scintigraphy in the other patient). Conclusions 99mTc-GLP1-SPECT/CT could be helpful examination in the management of patients with hypoglycemia enabling proper localization of the pancreatic lesion and effective

  14. Imaging of human pancreatic cancer xenografts by single-photon emission computed tomography with 99mTc-Hynic-PEG-AE105

    PubMed Central

    ZHANG, XIN; TIAN, YE; SUN, FANGFANG; FENG, HONGBO; YANG, CHUN; GONG, XIAOYAN; TAN, GUANG

    2015-01-01

    The elevated expression of urokinase-type plasminogen activator receptor (uPAR) is associated with the poor prognosis of pancreatic cancer patients. Thus, uPAR is a promising candidate as a molecular target for the non-invasive imaging of pancreatic cancer. The present study aimed to develop a technetium-99m (99mTc)-labeled uPAR-binding peptide for non-invasive single-photon emission computed tomography (SPECT) assessment of uPAR expression in pancreatic cancer xenograft models. A linear high-affinity uPAR peptide antagonist, Hynic-PEG-AE105, was labeled with 99mTc. Human uPAR-positive pancreatic cancer BxPC-3 cells were inoculated into nude mice. SPECT was performed in the pancreatic cancer xenograft mice models. The results showed that the rate of the 99mTc labeling of Hynic-PEG-AE105 was 97.72±1.73%. The tumor uptake of 99mTc-Hynic-PEG-AE105 was higher than the control inactive peptide 99mTc-Hynic-PEG-AE105mut at 4 h (3.37±0.11 vs. 1.36±0.18; P<0.001) and 6 h (3.64±0.25 vs. 1.28±0.20; P<0.001) (n=10). Moreover, a significant correlation was observed between the tumor uptake of 99mTc-Hynic-PEG-AE105 and uPAR expression (r=0.791, P=0.006). In conclusion, in the present study, a peptide-based SPECT tracer, 99mTc-Hynic-PEG-AE105, with a high purity and specific radioactivity was synthesized. 99mTc-Hynic-PEG-AE105 is a promising agent for the non-invasive determination of uPAR expression in pancreatic cancer. PMID:26622829

  15. Imaging of irradiated liver with Tc-99m-sulfur colloid and Tc-99m-IDA

    SciTech Connect

    Gelfand, M.J.; Saha, S.; Aron, B.S.

    1981-09-01

    In three cases, irradiated regions of liver failed to concentrate Tc-99m-sulfur colloid. In two of these three, imaging with Tc-99m-acetanilide iminodiacetic acid (IDA) agents within five days showed near normal hepatic uptake of this hepatobiliary imaging agent. The hepatic parenchymal cells may be imaged with Tc-99m-IDA in some irradiated regions of liver, despite loss of reticuloendothelial cell function.

  16. Relative biological effectiveness of 99mTc radiopharmaceuticals.

    PubMed

    Narra, V R; Sastry, K S; Goddu, S M; Howell, R W; Strand, S E; Rao, D V

    1994-12-01

    The radiotoxicity of three 99mTc-labeled compounds is investigated using spermatogenesis in mouse testis as the experimental model, and spermatogonial cell survival as the biological end point. The radiopharmaceuticals studied are pertechnetate (99mTcO4-), pyrophosphate (99mTc-PYP), and hydroxyethylene diphosphate (99mTc-HDP). The mean lethal doses at 37% survival (D37) are 0.70 +/- 0.06, 0.84 +/- 0.13, and 0.59 +/- 0.08 Gy for 99mTcO4-, 99mTc-PYP, and 99mTc-HDP, respectively. When these results are compared with the D37 value obtained with external x rays or internal gamma rays, the relative biological effectiveness (RBE) of these compounds are 0.94 +/- 0.09, 0.79 +/- 0.13, and 1.1 +/- 0.16, respectively. These results show that the radiotoxicity of 99mTc in mouse testis is essentially similar to that of low-LET radiations (i.e., RBE approximately 1). To understand these results, the distribution of these radiocompounds in the testis is determined and correlated with the observed RBE values. The expected range of RBE values for 99mTc radiopharmaceuticals in organs is 0.95 to 1.5, depending on the fraction of organ activity that is bound to DNA. This suggests that the Auger electrons emitted in the decay of 99mTc are not capable of causing extreme toxicity in vivo. These results provide further support for 99mTc as the radionuclide of choice for imaging in nuclear medicine. PMID:7700199

  17. The role of Tc-99m IDA hepatobiliary and Tc-99m colloid hepatic imaging in primary biliary cirrhosis

    SciTech Connect

    Aburano, T.; Yokoyama, K.; Shuke, N.; Kinuya, S.; Takayama, T.; Tonami, N.; Hisada, K. )

    1991-01-01

    To assess the presence of primary biliary cirrhosis, 15 patients at various histopathologic stages were studied by Tc-99m IDA hepatobiliary and/or Tc-99m colloid hepatic imaging. In the earlier stages (I and II), seven of eight patients (88%) showed uniform hepatic retention of Tc-99m IDA. Of seven patients in the same stage, however, four (57%) showed no abnormality on Tc-99m colliod imaging. In three of these four negative patients (75%), uniform hepatic retention of Tc-99m IDA was noted. In the later stages (III and IV), all seven patients showed decreased clearance with or without delayed tracer appearance in the intestine and prominent hepatic retention on Tc-99m IDA imaging; with Tc-99m colloid imaging there was enlargement of the spleen and increased activity in the spleen and bone marrow. Thus, Tc-99m IDA imaging is considered to be more useful in revealing this functional disorder at the earlier stage of primary biliary cirrhosis and in evaluating progression from an earlier to a later stage of disease. Tc-99m colloid imaging also effectively evaluated progression.

  18. Importance of markers in Tc-99m pyrophosphate myocardial images

    SciTech Connect

    Vasavada, P.J.; Micklos, T.J.; Nishiyama, H.

    1985-02-01

    A false-positive Tc-99m PYP myocardial scan may result due to gastric activity from the breakdown of radiopharmaceuticals and accumulation of Tc-99m pertechnetate in gastric cells. Importance of anatomic landmarks during early blood pool images is emphasized to prevent this error.

  19. (99m)Tc-labeled porphyrin-lipid nanovesicles.

    PubMed

    Lee, Jae-Ho; Shao, Shuai; Cheng, Kenneth T; Lovell, Jonathan F; Paik, Chang H

    2015-01-01

    Porphyrin-lipid nanovesicles (PLN) have been developed with intrinsic capabilities as activatable multimodal photonic contrast agents. Radiolabeling of PLN encapsulating drugs could eventually be able to provide quantitative in vivo information for diagnosing and treating diseases. In this study, we developed (99m)Tc-labeled porphyrin-lipid nanovesicles ((99m)Tc-PLN) as a cargo-encapsulated formulation without significant impact on liposome integrity and encapsulation stability. 50 mM calcein was encapsulated into PLN by probe sonication. The size of the PLN was about 150 nm. The PLN were then reacted with (99m)Tc using SnCl2 dissolved in 1 mM HCl as a reducing agent and incubated for 10 min at 22 °C. The radiolabeling efficiency and stability of (99m)Tc-PLN were evaluated by instant thin-layer chromatography and low-pressure liquid chromatography (LPLC). (99m)Tc labeling was successful with a >92% labeling efficiency. LPLC showed that the liposomal elution peaks of the porphyrin-lipid and the calcein overlapped with the radioactivity elution peak of (99m)Tc-labeled PLN. The (99m)Tc-labeling procedure did not change the size of PLN. Encapsulated calcein remained inert inside PLN. Thus, this work lays out a simple and effective radiolabeling method using SnCl2 in HCl in the preparation of (99m)Tc-PLN. PMID:24963601

  20. Detection of esophageal ulcerations with technetium-99m albumin sucralfate

    SciTech Connect

    Goff, J.S.; Adcock, K.A.; Schmelter, R.

    1986-07-01

    Technetium-99m albumin-sucralfate ((/sup 99m/Tc)Su) can be used to demonstrate peptic ulcer disease in man and animals. We evaluated the usefulness of (/sup 99m/Tc)Su for detecting various grades of esophagitis. (/sup 99m/Tc)Su adhered to the distal esophagus for up to 3 hr in five of six patients with esophageal ulcers but adhered to only two of nine with lesser degrees of esophagitis. No adherence was seen in five patients without esophagitis. Thus, (/sup 99m/Tc)Su may not be useful for detecting any but the most severe grade of esophagitis. Based on these results, we speculate that the previously documented beneficial effects of sucralfate on mild to moderate esophagitis may be due to other mechanisms besides adherence to the ulcerated mucosa.

  1. Technetium-99m antimony colloid for bone-marrow imaging

    SciTech Connect

    Martindale, A.A.; Papadimitriou, J.M.; Turner, J.H.

    1980-11-01

    Technetium-99m antimony colloid was prepared in our laboratory for bone-marrow imaging. Optimal production of colloid particles of size range 1 to 13 nm was achieved by the use of polyvinylpyrrolidone of mol. wt. 44,000. Electron microscopy was used to size the particles. Studies in rabbits showed exclusive concentration in the subendothelial dendritic phagocytes of the bone marrow. Pseudopods from these cells were found to traverse interendothelial junctions and concentrate colloid from the sinusoids. Imaging studies of bone marrow in rabbits showed the superiority of the Tc-99m antimony colloid over the much larger colloidal particle of Tc-99m sulfur colloid. Tissue distribution studies in the rat confirmed that bone-marrow uptake of Tc-99m antimony colloid was greater than that of Tc-99m sulfur colloid, although blood clearance was much slower.

  2. Development of kit formulations for (99m) TcN-MPO: a cationic radiotracer for myocardial perfusion imaging.

    PubMed

    Zheng, Yumin; Ji, Shundong; Tomaselli, Elena; Liu, Shuang

    2014-07-01

    The objective of this study was to develop a kit formulation for [(99m) TcN(mpo)(PNP5)](+) (MPO = 2-mercaptopyridine oxide), ((99m) TcN-MPO) to support its clinical evaluations as a SPECT radiotracer. Radiolabeling studies were performed using three different formulations (two-vial formulation and single-vial formulations with/without SnCl2 ) to explore the factors influencing radiochemical purity (RCP) of (99m) TcN-MPO. We found that the most important factor affecting the RCP of (99m) TcN-MPO was the purity of PNP5. (99m) TcN-MPO was prepared >98% RCP (n = 20) using the two-vial formulation. For single-vial formulations with/without SnCl2 , β-cyclodextrin (β-CD) is particularly useful as a stabilizer for PNP5. The RCP of (99m) TcN-MPO was 95-98% using β-CD, but its RCP was only 90-93% with γ-cyclodextrin (γ-CD). It seems that PNP5 fits better into the inner cavity of β-CD, which forms more stable inclusion complex than γ-CD in the single-vial formulations. The results from biodistribution and imaging studies in Sprague-Dawley rats clearly demonstrated biological equivalence of three different formulations. Single photon-emission computed tomography data suggested that high quality images could be obtained at 0-30-min post-injection without significant interference from the liver radioactivity. Considering the ease for (99m) Tc-labeling and high RCP of (99m) TcN-MPO, the non-SnCl2 single-vial formulation is an attractive choice for future clinical studies. PMID:25070025

  3. Novel Approach to Prepare {sup 99m}Tc-Based Multivalent RGD Peptides

    SciTech Connect

    Shuang Liu

    2012-10-24

    This project presents a novel approach to prepare the {sup 99m}Tc-bridged multivalent RGD (arginine-glycine-aspartate) peptides. This project will focus on fundamentals of {sup 99m}Tc radiochemistry. The main objective of this project is to demonstrate the proof-of-principle for the proposed radiotracers. Once a kit formulation is developed for preparation of the {sup 99m}Tc-bridged multivalent RGD peptides, various tumor-bearing animal models will be used to evaluate their potential for SPECT (single photon-emission computed tomography) imaging of cancer. We have demonstrated that (1) multimerization of cyclic RGD peptides enhances the integrin {alpha}{sub v}{beta}{sub 3} bonding affinity and radiotracer tumor uptake; (2) addition of G{sub 3} or PEG{sub 4} linkers makes it possible for two RGD motifs in 3P-RGD{sub 2} and 3G-RGD{sub 2} to achieve simultaneous integrin {alpha}{sub v}{beta}{sub 3} binding; and (3) multimers are actually bivalent (not multivalent), the presence of extra RGD motifs can enhance the tumor retention time of the radiotracer.

  4. Breast-milk radioactivity after a Tc-99m DTPA aerosol/Tc-99m MAA lung study

    SciTech Connect

    Mountford, P.J.; Hall, F.M.; Wells, C.P.; Coakley, A.J.

    1984-10-01

    Measurements were made of the concentration of Tc-99m activity in samples of breast milk following an administration of Tc-99m DTPA aerosol for a lung ventilation image and one of Tc-99m MAA for lung perfusion. The activity was 222 nCi/ml of milk (8.2 kBq/ml) at 2 hr after the MAA injection, and it was found to be excreted exponentially with an effective half-life of 4.6 hr. There was a small incorporation of Tc-99m into breast-milk protein. The authors conclude that the combined use of these two Tc-99m agents did not indicate the interruption of breast feeding beyond 24 hr after administration of the MAA, and that for an aerosol ventiliation study alone, breast feeding need not be interrupted for more than 4 hr after the test.

  5. Sustained Availability of Technetium-99m - Possible Paths Forward

    SciTech Connect

    Pillai, M R A; Dash, A; Knapp Jr, Russ F

    2013-01-01

    The availability of technetium-99m (99mTc) for single-photon imaging in diagnostic nuclear medicine is crucial, and current availability is based on the molybdenum-99 (99Mo)/99mTc generator fabricated from fission-based molybdenum (F 99Mo) produced by use of highly enriched uranium (HEU) targets. The use of HEU targets is being phased out because of risks related to nuclear material proliferation, so alternative strategies for production of both 99Mo and 99mTc are being evaluated intensely. There are evidently no plans for replacement of the limited number of reactors that have primarily provided most of the 99Mo. The uninterrupted, dependable availability of 99mTc is a crucial issue. For these reasons, new options being pursued include both reactor- and accelerator-based strategies to sustain the continued availability of 99mTc without the use of HEU. In this paper the scientific and economic issues for transitioning from HEU to non-HEU are also discussed. In addition, the comparative advantages, disadvantages, technical challenges, present status, future prospects, security concerns, economic viability, and regulatory obstacles are reviewed. In addition, the international actions in progress towards evolving possible alternative strategies to produce 99Mo and/or 99mTc are analyzed. The breadth of technologies and new strategies under development to provide 99Mo and 99mTc reflects both the broad interest in and the importance of the pivotal role of 99mTc in diagnostic nuclear medicine.

  6. 99mTc-labeled Therapeutic Inhaled Amikacin Loaded Liposomes

    PubMed Central

    Lee, Jae-Ho; Cheng, Kenneth T.; Malinin, Vladimir; Li, Zhili; Yao, Zhengsheng; Lee, Sung-Jin; Gould, Christine M.; Olivier, Kenneth N.; Chen, Clara; Perkins, Walter R.; Paik, Chang H.

    2014-01-01

    The radiolabeling of the liposome surface can be a useful tool for in vivo tracking of therapeutic drug loaded liposomes. We investigated radiolabeling therapeutic drug (i.e., an antibiotic, amikacin) loaded liposomes with 99mTc, nebulization properties of 99mTc-labeled liposomal amikacin for inhalation (99mTc-LAI), and its stability by size exclusion low pressure liquid chromatography (LPLC). LAI was reacted with 99mTc using SnCl2 dissolved in ascorbic acid as a reducing agent for 10 min at room temperature. The labeled products were then purified by anion exchange resin. The purified 99mTc-LAI in 1.5% NaCl solution was incubated at 4oC to assess its stability by LPLC. The purified 99mTc-LAI was subjected to studies with a clinically used nebulizer (PARI eFlow®) and the Anderson Cascade Impactor (ACI). The use of ascorbic acid at 0.91 mM resulted in a quantitative labeling efficiency. The LPLC profile showed that the liposomal peak of LAI detected by a UV monitor at both 200 nm and 254 nm overlapped with the radioactivity peak of 99mTc-LAI, indicating that 99mTc-LAI is suitable for tracing LAI. The ACI study demonstrated that the aerosol droplet size distribution determined gravimetrically was similar to that determined by radioactivity. The liposome surface labeling method using SnCl2 in 0.91mM ascorbic acid produced 99mTc-LAI with a high labeling efficiency and stability that are adequate to evaluate the deposition and clearance of inhaled LAI in the lung by gamma scintigraphy. PMID:23879241

  7. (99m)Tc-labeled therapeutic inhaled amikacin loaded liposomes.

    PubMed

    Lee, Jae-Ho; Cheng, Kenneth T; Malinin, Vladimir; Li, Zhili; Yao, Zhengsheng; Lee, Sung-Jin; Gould, Christine M; Olivier, Kenneth N; Chen, Clara; Perkins, Walter R; Paik, Chang H

    2013-12-01

    The radiolabeling of the liposome surface can be a useful tool for in vivo tracking of therapeutic drug loaded liposomes. We investigated radiolabeling therapeutic drug (i.e. an antibiotic, amikacin) loaded liposomes with (99m)Tc, nebulization properties of (99m)Tc-labeled liposomal amikacin for inhalation ((99m)Tc-LAI), and its stability by size exclusion low-pressure liquid chromatography (LPLC). LAI was reacted with (99m)Tc using SnCl2 dissolved in ascorbic acid as a reducing agent for 10 min at room temperature. The labeled products were then purified by anion exchange resin. The purified (99m)Tc-LAI in 1.5% NaCl solution was incubated at 4 °C to assess its stability by LPLC. The purified (99m)Tc-LAI was subjected to studies with a clinically used nebulizer (PARI eFlow®) and the Anderson Cascade Impactor (ACI). The use of ascorbic acid at 0.91 mM resulted in a quantitative labeling efficiency. The LPLC profile showed that the liposomal peak of LAI detected by a UV monitor at both 200 nm and 254 nm overlapped with the radioactivity peak of (99m)Tc-LAI, indicating that (99m)Tc-LAI is suitable for tracing LAI. The ACI study demonstrated that the aerosol droplet size distribution determined gravimetrically was similar to that determined by radioactivity. The liposome surface labeling method using SnCl₂ in 0.91 mM ascorbic acid produced (99m)Tc-LAI with a high labeling efficiency and stability that are adequate to evaluate the deposition and clearance of inhaled LAI in the lung by gamma scintigraphy. PMID:23879241

  8. Lymphoscintigraphy in melanoma patients using Tc-99m dextran

    SciTech Connect

    Marciano, D.; Padgett, H.; Henze, E.; Carlson, C.; Bennett, L.R.

    1984-01-01

    Surgical removal of regional lymph nodes draining the site of a melanoma is a generally practiced procedure. It is often difficult in many cases of truncal melanomas near the midline or near the waistline to determine which group or groups of nodes to remove. Colloidal Au-198, Tc-99m sulfur colloid, and Tc-99m antimony sulfur colloid have all been used and have given useful clinical information. Objections, however, have been raised to the local radiation dose with these compounds. To reduce this problem while obtaining greater information on lymph flow, the authors have studied dextran, a macromolecule commonly used as plasma substitute. Dextran (average mol. wt. 72,000) labeled with Tc-99m has been used to study lymph drainage from the site of truncal melanoma in 29 patients. Serial images in the first hour following intradermal injection clearly demonstrate tracer in efferent lymphatics within 5 to 10 minutes, and brief pooling in the regional lymph nodes between 20 and 60 minutes. When compared with particulate tracers such as micro Tc-99m sulfur colloid, the Tc-99m dextran appears to move much faster through the lymphatics. Overall distribution of the Tc-99m dextran to lymph nodes is very similar to previous findings with micro Tc-99m sulfur colloid. Dextran drainage to more than one group of regional nodes was seen in 12/29 patients as compared with 17/50 patients using micro Tc-99m sulfur colloid. The superior images with Tc-99m dextran appear to make it the agent of choice.

  9. Abnormal regional cerebral blood flow found by technetium-99m ethyl cysteinate dimer brain single photon emission computed tomography in systemic lupus erythematosus patients with normal brain MRI findings.

    PubMed

    Chen, J J-H; Yen, R-F; Kao, A; Lin, C-C; Lee, C-C

    2002-11-01

    In this study, technetium-(99m) ethyl cysteinate dimer ((99m)Tc ECD) brain single photon emission computed tomography (SPECT) was used to detect regional cerebral blood flow (rCBF) of the brain in SLE patients with normal brain magnetic resonance imaging (MRI) findings. Twenty female SLE patients were enrolled in this study, divided into two groups. Group 1 consisted of 10 patients with neuropsychiatric manifestations. Group 2 consisted of 10 patients without neuropsychiatric manifestations. All patients had normal brain MRI findings. Another 10 SLE patients with abnormal MRI findings were included as group 3 for comparison. Meanwhile, 10 healthy female volunteers also underwent brain MRI and (99m)Tc ECD brain SPECT for comparison. The scans revealed hypoperfusion lesions in 9/20 (45%) SLE patients, including 7/10 (70%) cases in group 1 and 2/10 (20%) cases in group 2. In contrast, all 10 patients (100%) in group 3 had abnormal (99m)Tc ECD brain SPECT findings. The parietal lobes were the most commonly involved areas. We conclude that (99m)Tc ECD brain SPECT is more sensitive for detecting rCBF changes than is brain MRI in detecting the brain anatomic changes, and may have a diagnostic value in lupus cerebral involvement. However, (99m)Tc ECD brain SPECT may not be indicated for SLE patients with normal MRI and mild neuropsychiatric symptoms/signs, such headaches and dizziness. PMID:12447638

  10. Technetium-99m MDP vs technetium-99m dicarboxypropane diphosphonate. A clinical comparison in various pathologic conditions

    SciTech Connect

    Godart, G.; Durez, M.; Bevilacqua, M.; Abramovici, J.; Robience, Y.

    1986-02-01

    The performance of Tc-99m MDP vs Tc-99m dicarboxypropane diphosphonate (DPD) was evaluated in 20 patients with various skeletal bone diseases. Each patient was investigated twice, with an interval of three days between studies and using the same protocol, hence each case served as its own control. The results were: In a subjective interpretation by five independent and experienced investigators, the difference between agents was small, yet in favor of MDP. Region of interest (ROI) analysis of the pooled results in 74.4% of all cases shows a higher bone lesion to normal bone ratio (BL/NB), and in 79.3% of all cases, a better bone lesion to soft tissue ratio (BL/ST) with Tc-99m MDP. When considering pathology types separately, the BL/NB ratio of Tc-99m MDP was 17.7% higher than the one of Tc-99m DPD in metastases, 9.5% higher in rheumatoid arthritis, 2.8% higher in metabolic diseases, and 24% higher in bone fractures. Student's paired t test on the pooled BL/NB ratios shows a difference of 15.5% for Tc-99m MDP, significant at P = 0.00155. The overall results of our study favor Tc-99m MDP.

  11. Imaging considerations for a technetium-99m myocardial perfusion agent

    SciTech Connect

    English, R.J.; Jones, A.G.; Davison, A.; Lister-James, J.; Campbell, S.; Holman, B.L.

    1986-03-01

    Myocardial perfusion imaging with /sup 201/Tl chloride suffers from a number of physical, geometric, and dosimetric constraints that could be diminished if an agent labeled with /sup 99m/Tc were available. The cationic complex /sup 99m/Tc hexakis-(t-butylisonitrile)technetium(I) ((/sup 99m/Tc)TBI) has been shown to concentrate in the myocardial tissue of both animals and humans, with preliminary clinical studies demonstrating a number of technical attributes not possible with /sup 201/Tl. Technetium-99m-TBI is a promising myocardial imaging agent that may permit high quality planar, gated, and tomographic imaging of both myocardial ischemia and infarction with reduced imaging times and improved resolution.

  12. 99M-Technetium labeled tin colloid radiopharmaceuticals

    DOEpatents

    Winchell, Harry S.; Barak, Morton; Van Fleet, III, Parmer

    1976-07-06

    An improved 99m-technetium labeled tin(II) colloid, size-stabilized for reticuloendothelial organ imaging without the use of macromolecular stabilizers and a packaged tin base reagent and an improved method for making it are disclosed.

  13. Radiation absorbed dose from technetium-99m DTPA

    SciTech Connect

    Smith, T.; Zanelli, G.D.; Veall, N.

    1987-02-01

    The whole-body retention of intravenously administered (99mTc)DTPA was measured by urine analysis and whole-body counting in eight normal subjects. On average, the elimination of (99mTc)DTPA was faster in these subjects than in 11 patients under study for hypertension whose whole-body retention data were used in MIRD Dose Estimate Report No. 12. The average residence time for (99mTc)DTPA in total body, less bladder contents, was only 65% of the MIRD value. However, despite this difference, the dosimetry is similar in both cases largely owing to the influence of radioactivity in bladder contents. Approximately 2-3% of the administered radioactivity was retained in the body for a time that was long relative to the physical half-life of 99mTc, and probably reflects a small amount of protein binding of the DTPA preparation.

  14. [Diagnosis of achalasia using 99m-Tc pertechnetate scintigraphy].

    PubMed

    Mikosch, P; Gallowitsch, H J; Kresnik, E; Lind, P

    1997-06-01

    A 73-year-old patient presented a 99mTc scintiscan with a focal tracer accumulation left and caudal of the thyroid gland. Further investigations with sonography, CT, esophagoscopy and barium swallow provided the diagnosis of achalasia as the reason for focal 99mTc retention caudal of the thyroid gland. Explanation for 99mTc accumulation within the esophagus may be the nonspecific accumulation of 99mTc not only in the thyroid gland but also in the salivary glands. Excretion of the tracer follows with the saliva. Structural and motor disorders of the esophagus can thus lead to focal tracer retention within the esophagus simulating thyroid tissue. PMID:9395425

  15. [Imaging of thromboembolism by scintigraphy with the 99m-technetium-labelled synthetic peptide P280].

    PubMed

    Lastoria, S; Vergara, E; Varrella, P; Muto, P; Acampa, W; Caracò, C; Salvatore, M

    1995-12-01

    P280, a synthetic peptide composed of 26 aminoacids, has high affinity (Kd = 100 nM) and specificity for the glycoprotein IIb/IIIa (GPIIb/IIIa) receptor expressed on activated platelets. In this study we investigated the potential usefulness of imaging deep vein thrombosis (DVT) and pulmonary embolism (PE) in humans with 99mTc-P280. In 15 patients (9 men and 6 women; mean age +/- s.d.: 49.2 +/- 14.1) with known DVT and/or PE, serial images were acquired within 24 hours of the injection of approximately 200 micrograms of P280 radiolabelled with 10-23 mCi of 99mTc. P280 was labelled with the ligand exchange method using 99mTc-glucoheptonate. Rapid blood clearance (< or = 5% ID was still circulating in 1 hour) enabled identification of thrombi as early as 60 minutes after the injection, with significant thrombi-to-background ratios (range: 2-4) in 11/15 patients (73%), in 7/9 with DVT, in 2/3 with PE and in 2/3 patients with both DVT and PE. Radiotracer uptake was clearly detectable also in late scans, which confirms that 99mTc-P280 specifically binds to the thrombi through a receptor-mediated mechanism. PE localizations were detectable 3-4 hours after peptide injection, and in 2 cases SPECT enabled the detection of thrombi missed on planar views. Conversely, the test was negative in 4 patients who had the onset of clinical symptoms and the diagnosis of DVT and/or PE more than 40 days before scintigraphy. The lack of 99mTc-P280 uptake in the latter patients suggested that the peptide does not bind to thrombi when thrombogenesis is not active. These preliminary results clearly indicate scintigraphy with 99mTc-P280 to be a suitable, noninvasive and highly specific tool to image fresh clots causing DVT and/or PE. Thus, this technique might overcome the limitations of the imaging procedures currently in use. PMID:8685469

  16. Hepatic uptake of technetium-99m diphosphonate in thalassemia major

    SciTech Connect

    Levy, H.M.; Smith, R.

    1986-02-01

    Two cases of thalassemia major are presented in which bone scintigraphy demonstrated diffuse hepatic uptake of Tc-99m diphosphonate. Although abnormal splenic and renal uptake of Tc-99m phosphates has been reported in patients with thalassemia major, hepatic uptake has not been reported previously. This scintigraphic finding is presumably due to increased iron deposition in the liver, resulting from increased iron turnover and retention in these patients and from multiple previous blood transfusions.

  17. Post meningitis subdural hygroma: Anatomical and functional evaluation with (99m)Tc-ehylene cysteine dimer single photon emission tomography/computed tomography.

    PubMed

    Sharma, Punit; Mishra, Ajiv; Arora, Geetanjali; Tripathi, Madhavi; Bal, Chandrasekhar; Kumar, Rakesh

    2013-01-01

    Subdural hygroma is the collection of cerebrospinal fluid in the subdural space. Most often these resolve spontaneously. However, in cases with neurological complications surgical drainage may be needed. We here, present the case of an 8-year-old boy with post meningitis subdural hygroma. (99m)Tc-ehylene cysteine dimer ((99m)Tc-ECD) hybrid single photon emission tomography/computed tomography (SPECT/CT) carried out in this patient, demonstrated the subdural hygroma as well as the associated cerebral hypoperfusion. If (99m)Tc-ECD SPECT/CT is integrated into management of these patients, it can help in decision making with respect to conservative versus surgical management. PMID:24019670

  18. (99m) Tc-labeled tetramer and pentamer of single-domain antibody for targeting epidermal growth factor receptor in xenografted tumors.

    PubMed

    Li, Chongjiao; Feng, Hongyan; Xia, Xiaotian; Wang, Lifei; Gao, Bin; Zhang, Yongxue; Lan, Xiaoli

    2016-06-30

    The single-domain antibody EG2 can be fused with right-handed coiled-coil (RHCC) and human cartilage oligomeric matrix protein (COMP), to form the multivalent antibodies EG2-RHCC and EG2-COMP. We labeled these two antibodies with (99m) Tc and assessed their targeting efficiency for epidermal growth factor receptor (EGFR). Cell binding, uptake, efflux, and blocking studies were performed with EGFR high- and/or low-expressing cells with (99m) Tc-labeled EG2-RHCC or EG2-COMP. Single photon-emission computed tomography (SPECT) imaging and biodistribution studies were further carried out. Both (99m) Tc-EG2-RHCC and (99m) Tc-EG2-COMP can specially bind to EGFR in vitro. SPECT imaging showed that A431, which expresses high levels of EGFR, was clearly visible 6 h after (99m) Tc-EG2-COMP injection; however, it was not detectable after administration of (99m) Tc-EG2-RHCC. Uptake of both antibodies by the non-EGFR-secreting OCM-1 tumors was low. EG2-COMP shows promise in identifying EGFR over-expression in tumors; however, EG2-RHCC may not be suitable for targeting EGFR in vivo. PMID:27123559

  19. The first experience of using of 99mTc-Al2O3 for detection of sentinel lymph nodes in breast cancer

    NASA Astrophysics Data System (ADS)

    Doroshenko, A.; Chernov, V.; Medvedeva, A.; Zeltchan, R.; Slonimskaya, E.; Varlamova, N.; Skuridin, V.; Dergilev, A.; Sinilkin, I.

    2016-06-01

    Purpose: to study the feasibility of using the new radiopharmaceutical based on the technetium-99m-labeled gamma-alumina for identification of sentinel lymph nodes (SLNs) in breast cancer patients. Materials and methods. The study included two groups of breast cancer patients who underwent single photon emission computed tomography (SPECT) and intraoperaive gamma probe identification of sentinel lymph nodes (SLNs). To identify SLNs, the day before surgery Group I patients (n=34) were injected with radioactive 99mTc-Al203, and Group II patients (n=30) received 99mTc-labeled phytate colloid. Results. A total of 37 SLNs were detected in Group I patients. The number of identified SLNs per patient ranged from 1 to 2 (the average number of identified SLNs was 1.08). Axillary lymph nodes were the most common site of SLN localization. At 18 hours after 99mTc-Al203 injection, the percentage of its accumulation in the SLN was 7-11% (of the counts in the injection site) by SPECT and 17-31% by gamma probe detection. In Group II patients, SLNs were detected in 27 patients. At 18 hours after injection of the phytate colloid, the percentage of its accumulation in the SLN was 1.5-2% out of the counts in the injection site by SPECT and 4-7% by gamma probe. Conclusion. The new radiopharmaceutical based on the 99mTc - Al203 demonstrates high accumulation in SLNs without redistribution through the entire lymphatic basin. Sensitivity and specificity of 99mTc - Al203 were 100% for both SPECT and intraoperative gamma probe identification.

  20. Labeling cellular elements of blood with Technetium-99m

    SciTech Connect

    Dewanjee, M.K.

    1990-08-01

    The purpose of this proposal is to develop new technique of labeling platelets and white cells with Tc-99m radionuclide. The conditions of labeling canine platelets and white cells with the lipid-soluble Tc-99m HMPAO have been optimized. The function of labeled platelets were evaluated by the determination of platelet survival time and recovery and these values were compared with that of In-111 tropolone labeled platelets. We developed the bilateral femoral catheterization model for the evaluation of platelet-thrombosis on control and heparin-bonded catheters in dogs. We are evaluating platelet thrombosis in the hollow-fiber hemodialyzer with Tc-99m and In-111 labeled platelets. We have developed the flow-loop for in vitro studies and are using a pig model for quantitation of platelet-consumption during hemodialysis. We are currently evaluating the new technique of platelet and white cell-labeling with Tc-99m and testing them in animal models of thrombosis and infection (osteo-myelitis). We are also using the Tc-99m HMPAO labeled mixed white cells in the early diagnosis (3-hour post-injection) of acute and chronic infection in patients and comparing the results with that of IN-111 oxine labeled white cells.

  1. Evaluation of deoxyribonucleic acid toxicity induced by the radiopharmaceutical 99mTechnetium-Methylenediphosphonic acid and by stannous chloride in Wistar rats.

    PubMed

    Mattos, José Carlos Pelielo De; Matos, Vanessa Coutinho de; Rodrigues, Michelle Pinheiro; Oliveira, Marcia Betânia Nunes de; Dantas, Flavio José S; Santos-Filho, Sebastião David; Bernardo-Filho, Mario; Caldeira-de-Araujo, Adriano

    2012-01-01

    Radiopharmaceuticals are employed in patient diagnostics and disease treatments. Concerning the diagnosis aspect, technetium-99m (99mTc) is utilized to label radiopharmaceuticals for single photon computed emission tomography (SPECT) due to its physical and chemical characteristics. 99mTc fixation on pharmaceuticals depends on a reducing agent, stannous chloride (SnCl(2)) being the most widely-utilized. The genotoxic, clastogenic and anegenic properties of the 99mTc-MDP(methylene diphosphonate used for bone SPECT) and SnCl(2) were evaluated in Wistar rat blood cells using the Comet assay and micronucleus test. The experimental approach was to endovenously administer NaCl 0.9% (negative control), cyclophosphamide 50 mg/kg b.w. (positive control), SnCl(2) 500 μg/mL or 99mTc-MDP to animals and blood samples taken immediately before the injection, 3, and 24 h after (in the Comet assay) and 36 h after, for micronucleus test. The data showed that both SnCl(2) and 99mTc-MDP-induced deoxyribonucleic acid (DNA) strand breaks in rat total blood cells, suggesting genotoxic potential. The 99mTc-MDP was not able to induce a significant DNA strand breaks increase in in vivo assays. Taken together, the data presented here points to the formation of a complex between SnCl(2) in the radiopharmaceutical 99mTc-MDP, responsible for the decrease in cell damage, compared to both isolated chemical agents. These findings are important for the practice of nuclear medicine. PMID:23117436

  2. Development of (99m)Tc-labeled asymmetric urea derivatives that target prostate-specific membrane antigen for single-photon emission computed tomography imaging.

    PubMed

    Kimura, Hiroyuki; Sampei, Sotaro; Matsuoka, Daiko; Harada, Naoya; Watanabe, Hiroyuki; Arimitsu, Kenji; Ono, Masahiro; Saji, Hideo

    2016-05-15

    Prostate-specific membrane antigen (PSMA) is expressed strongly in prostate cancers and is, therefore, an attractive diagnostic and radioimmunotherapeutic target. In contrast to previous reports of PMSA-targeting (99m)Tc-tricarbonyl complexes that are cationic or lack a charge, no anionic (99m)Tc-tricarbonyl complexes have been reported. Notably, the hydrophilicity conferred by both cationic and anionic charges leads to rapid hepatobiliary clearance, whereas an anionic charge might better enhance renal clearance relative to a cationic charge. Therefore, an improvement in rapid clearance would be expected with either cationic or anionic charges, particularly anionic charges. In this study, we designed and synthesized a novel anionic (99m)Tc-tricarbonyl complex ([(99m)Tc]TMCE) and evaluated its use as a single-photon emission computed tomography (SPECT) imaging probe for PSMA detection. Direct synthesis of [(99m)Tc]TMCE from dimethyl iminodiacetate, which contains both the asymmetric urea and succinimidyl moiety important for PSMA binding, was performed using our microwave-assisted one-pot procedure. The chelate formation was successfully achieved even though the precursor included a complicated bioactive moiety. The radiochemical yield of [(99m)Tc]TMCE was 12-17%, with a radiochemical purity greater than 98% after HPLC purification. [(99m)Tc]TMCE showed high affinity in vitro, with high accumulation in LNCaP tumors and low hepatic retention in biodistribution and SPECT/CT studies. These findings warrant further evaluation of [(99m)Tc]TMCE as an imaging agent and support the benefit of this strategy for the design of other PSMA imaging probes. PMID:27073053

  3. Use of (/sup 99m/Tc)-HM-PAO in the diagnosis of primary degenerative dementia

    SciTech Connect

    Testa, H.J.; Snowden, J.S.; Neary, D.; Shields, R.A.; Burjan, A.W.; Prescott, M.C.; Northen, B.; Goulding, P.

    1988-12-01

    The clinical value of single photon emission computed tomography (SPECT) in the differential diagnosis of dementia due to cerebral atrophy was evaluated by comparing the pattern of distribution (/sup 99m/Tc)-HM-PAO in three dementing conditions. Imaging was carried out in 26 patients with suspected Alzheimer's disease, 14 with dementia of the frontal-lobe type, and 13 with progressive supranuclear palsy. Images were evaluated and reported without knowledge of clinical diagnosis with respect to regions of reduced uptake of tracer. Reduced uptake in the posterior cerebral hemispheres was characteristic of Alzheimer's disease, while selective anterior hemisphere abnormalities characterized both dementia of the frontal-lobe type and progressive supranuclear palsy. The latter conditions could be distinguished on the basis of the appearance of integrity of the rim of the frontal cortex. The technique has an important role in the differentiation of degenerative dementias.

  4. Radionuclide imaging of myocardial infarction using Tc-99m TBI

    SciTech Connect

    Holman, B.L.; Campbell, S.; Kirshenbaum, J.M.; Lister-James, J.; Jones, A.G.; Davison, A.; Antman, E.

    1985-05-01

    The cationic complex Tc-99m t-butylisonitrile (TBI) concentrates in the myocardial tissue of several animal species. Its myocardial distribution is proportional to blood flow both in zones of ischemia and in normal myocardium at rest. Planar, tomographic, and gated myocardial images have been obtained using Tc-99m TBI in the human. The authors investigated the potential application of Tc-99m TBI imaging to detect and localize myocardial infarction. Four subjects without clinical evidence of cardiovascular disease and five patients with ECG evidence of previous myocardial infarction were studied. Tc-99m TBI (10mCi) was injected intravenously with the patient in a resting state with planar imaging in the anterior, 30 and 70 degree LAO projections beginning one hr after injection. The distribution of the tracer was homogeneous throughout the left ventricular wall in the normal subjects. Regional perfusion defects were present in 4/5 of the patients with myocardial infarction. Location of the defects corresponded to the location of the infarct using ECG criteria (2 inferoposterior and 2 anterior). The patient in whom the Tc-99m TBI image appeared normal had sustained a subendocardial myocardial infarct which could not be localized by ECG; the other 4 pts had transmural infarcts. Anterior and 30 degree LAO images were of excellent quality in all cases; there was overlap of the liver on the inferior wall of the left ventricle on the 70 degree LAO views. The authors conclude that accurate perfusion imaging may be possible using Tc-99m TBI in patients with transmural myocardial infarction.

  5. Leukocyte labeling with isonitrile complexes of Tc-99m

    SciTech Connect

    Van den Abbeele, A.D.; Solorzano, C.; Jones, A.G.; Beardsley, D.S.; Treves, S.; Davison, A.

    1985-05-01

    Leukocyte labelling with Tc-99m may result in a useful method for the detection and localization of active inflammatory processes in patients, particularly in the pediatric population. Previous studies qin this laboratory have shown that hexakis(alkylisonitrile)technetium(I) complexes readily label V79 lung fibroblasts in vitro, and this work is now being extended to isolated human white blood cells (WBC). Two lipophilic water-soluble technetium cations, the t-butyl (Tc-99m(TBI)) and cyclohexyl (Tc-99m(CHI)) analogs, were prepared essentially ligand-free at no-carrier-added levels in aqueous media and introduced in 10% propylene glycol/90% normal saline solution to WBC at room temperature. The cells were isolated from whole blood via sedimentation, centrifugation, and hypotonic hemolysis of the red blood cells. The labeling yield was studied as a function of incubation time (10-45 min), amount of activity (0.35-8.0 mCi), and total WBC (2.5 x 10/sup 7/-1.3 x 10/sup 8/). After 10 min incubation using 10/sup 8/ cells, the initial uptake of Tc-99m(TBI) was 40%, of which 50% remained bound after one saline wash. By contrast, the labeling efficiency with Tc-99m(CHI) was 85%, with 90% of the label still bound after washing. The labeling yield was unrelated to activity levels of incubation time, but was proportional to the number of WBC present. The entire process could be complemented in approximately one hour. The labeling yields with Tc-99m-(CHI) are comparable to those now obtained with the clinically available In-111 oxine.

  6. Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m

    SciTech Connect

    2010-01-01

    Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m is a linear electron accelerator-based technology for producing medical imaging radioisotopes from a separation process that heats, vaporizes and condenses the desired radioisotope. You can learn more about INL's education programs at http://www.facebook.com/idahonationallaboratory.

  7. Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m

    ScienceCinema

    None

    2013-05-28

    Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m is a linear electron accelerator-based technology for producing medical imaging radioisotopes from a separation process that heats, vaporizes and condenses the desired radioisotope. You can learn more about INL's education programs at http://www.facebook.com/idahonationallaboratory.

  8. [Complementary scintigraphic examinations (99mTc-MDP, 99mTc-MIBI and Octreoscan) in breast neoplasm assessment].

    PubMed

    Stefănescu, C; Chossiere, L; Rusu, V; Meignan, M

    1996-01-01

    Scintigraphic imagery was used in breast carcinoma mostly for the bone metastases screening, using 99mTc-MDP. Others radiopharmaceuticals can be used to visualize either the primary tumour or the soft tissues metastases. It's mainly the case of 99mTc-MIBI, and also of some somatostatin analogues, like Octreoscan. This case report of a patient with a T3N1M+ breast adenocarcinoma having different secondary sites represent also a prove of the complementarity of these explorations, which give the possibility of diagnostic and therapeutic evaluation and, in the same time, the possibility of a better understood of the metastasizing mechanism. PMID:9455458

  9. Poor Tc-99m dimercaptosuccinic acid uptake, re-evaluation with Tc-99m MAG3 scintigraphy in Lowe syndrome

    PubMed Central

    Koca, Gokhan; Atilgan, Hasan Ikbal; Demirel, Koray; Diri, Akif; Korkmaz, Meliha

    2011-01-01

    Tc-99m dimercaptosuccinic acid (DMSA) is filtered through the glomeruli and reabsorbed by the proximal tubules as low molecular weight proteins. In Lowe syndrome this mechanism is impaired and so poor DMSA uptake is seen. Poor DMSA uptake was shown in very few studies, but none mentioned normal Tc-99m MAG3 uptake. In this case, the patient had poor DMSA uptake, normal MAG3 uptake and a neurogenic bladder in anterior to the left kidney that attenuates left kidney. PMID:23559713

  10. Synthesis and biodistribution of neutral lipid-soluble Tc-99m complexes that cross the blood-brain barrier. [Monkeys

    SciTech Connect

    Kung, H.F.; Molnar, M.; Billings, J.; Wicks, R.; Blau, M.

    1984-03-01

    Three Tc-99m-labeled neutral 1,2-dithia-5,8-diazacyclodecane (BAT) chelates that are capable of crossing the blood-brain barrier (BBB) were prepared and evaluated. Biodistribution (i.v.) in rats showed a significant brain uptake (1-3%/whole brain) at 2 min. At 15 min the uptake dropped to about a tenth of the original level, indicating free passage in both directions across the BBB. Gamma camera images of a monkey confirmed the high initial brain uptake. This group of Tc-99m BAT compounds clearly exhibited in vivo stability and the ability to cross the BBB after an i.v. injection. Derivatives containing tertiary amine groups should have prolonged brain retention and might be suitable for SPECT studies of brain perfusion.

  11. Joint scintigraphy using technetium-99m pyrophosphate in experimental hemarthrosis

    SciTech Connect

    Salimi, Z.; Vas, W.; Restrepo, G.

    1986-02-01

    To determine the validity of a method for induction of experimental hemarthrosis in dogs and for the nuclear imaging of hemarthrosis, serial technetium-99m pyrophosphate ((/sup 99m/Tc)PYP) flow and blood-pool scans were performed monthly in eight dogs who received bi-weekly injections of autologous blood into their femoro-tibial joints (also called stifle joint). In four control dogs, one joint was injected with saline while the other joint received only a sham injection. In addition, two dogs received intra-articular injections of autologous blood into their right stifle joint and saline into their left stifle joint. These dogs were studied with /sup 99m/TcO/sub 4/ joint scintigraphy at monthly intervals. The dogs were periodically taken out of the study and explored surgically. Pathologic examination of synovial tissue was performed. Serial radiographs were also obtained and correlated with the scan and surgical findings. There was a striking abnormal increase in blood-pool activity of (/sup 99m/Tc)PYP in the treated stifle joints, commencing at the first examination after 1 mo of blood injections and continuing for the length of the study. All radiographs showed only minimal joint space widening and some soft-tissue swelling. On pathologic examination, both grossly and microscopically, there was profuse pannus formation, with intense inflammatory infiltrate replacing much of the subsynovial fat. The scintigraphic findings correlated well with these pathologic findings. This study not only validates this method for simulating hemophilic hemarthrosis but also suggests that (/sup 99m/Tc)PYP joint scintigraphy is a simple, and noninvasive method for monitoring the early changes in hemophilic arthropathy and is superior to pertechnetate imaging for this disease process.

  12. (99m) Tc radiolabeling and biological evaluation of nanoparticles functionalized with a versatile coating ligand.

    PubMed

    Felber, Michael; Bauwens, Matthias; Mateos, José M; Imstepf, Sebastian; Mottaghy, Felix M; Alberto, Roger

    2015-04-13

    Radiolabeling allows noninvasive imaging by single photon emission computed tomography (SPECT) or positron emission tomography (PET) for assessing the biodistribution of nanostructures. Herein, the synthesis of a new coating ligand for gold nanoparticles (AuNPs) and quantum dots (QDs) is reported. This ligand is multifunctional; it combines the metal chelate with conjugating functions to biological vectors. The concept allows the coupling of any targeting function to the chelator; an example for the prostate specific membrane antigen is given. Derivatized NPs can directly be labeled in one step with [(99m) Tc(OH2 )3 (CO)3 ](+) . AuNPs in particular are highly stable, a prerequisite for in vivo studies excluding misinterpretation of the biodistribution data. AuNPs with differing sizes (7 and 14 nm core diameter) were administered intravenously into nude NMRI mice bearing LNCaP xenografts. MicroSPECT images show for both probes rapid clearance from the blood pool through the hepatobiliary pathway. The 7 nm AuNPs revealed a significantly higher bone uptake than the 14 nm AuNPs. The high affinity towards bone mineral is further confirmed in vitro with hydroxyapatite. PMID:25765900

  13. Comparison of technetium-99m IgG with technetium-99m red blood cells labeling in cardiac blood-pool scintigraphy: a preliminary study.

    PubMed

    Javadi, Hamid; Asli, Isa Neshandar; Semnani, Shahriar; Jallalat, Sara; Ansari, Mojtaba; Amini, Abdullatif; Barekat, Maryam; Assadi, Majid

    2011-01-01

    This first clinical prospective study was conducted to use of technetium-99m immunoglobulin G ((99m)Tc-IgG) as compared with autologous (99m)Tc-red blood cells (RBC) in gated blood pool ventriculography. We studied 12 patients who referred to us for a possible diagnosis of liver hemangioma or infection. Six patients underwent gated planar blood pool (GPBP) acquisition using (99m)Tc-RBC and 6 GPBP acquisition using (99m)Tc-IgG. The use of (99m)Tc-IgG in cardiac blood pool studies provided comparable images to (99m)Tc-RBC. In conclusion, (99m)Tc-IgG, which is readily available and needs only a single injection, may be an attractive alternative to (99m)Tc-RBC for the estimation of various cardiac function parameters like left ventricular function. PMID:21512662

  14. A geometric method of measuring the left ventricular ejection fraction on gated Tc-99m sestamibi myocardial imaging.

    PubMed

    Miron, S D; Finkelhor, R; Penuel, J H; Bahler, R; Bellon, E M

    1996-06-01

    Geometric measurements of the left ventricular diameters as used in biplane angiocardiography and echocardiography were applied to gated SPECT Tc-99m sestamibi myocardial scintigrams in order to calculate the left ventricular ejection fraction. These measurements take no longer than 5 minutes and require no additional computer software. In a review of 79 examinations, the left ventricular ejection fraction calculated using these measurements correlated well with the echocardiographically estimated ejection fraction (r = 0.78, P < 0.0001). The technique is highly reproducible with an intraobserver correlation of r = 0.94 and interobserver correlation of r = 0.93. PMID:8744176

  15. [A new lymph node imaging agent--99mTc-polyphase liposome oleatis (99mTc-plo)].

    PubMed

    Yu, B F

    1988-07-01

    A new lymph node radio-imaging agent, technetium-99m polyphase liposome oleatis (99mTc-plo), has recently been developed. Polyphase liposome oleatis was labelled with radionuclide by stannous chloride method. The labelled rate was 90% or more as technically identified by thin layer chromatography, external gamma-camera imaging and radioautography. In animal experiment, 0.2-0.3 ml (0.2 mci) of the 99mTc-plo was injected subcutaneously into the toes web of rats. After half an hour, the regional lymph nodes of popliteal fossa were visualized very clearly. The imaging figures may keep their distinct shadow up to 24 hours. The tested rabbits were sacrificed 10 hours after 99mTc-plo injection for detecting various kinds of tissue and organ with a scintillation counter. The regional lymph nodes revealed the highest uptake rate of the new agent, 12,116; 1,303; 1,615 times higher than that of the adjacent muscles, liver and spleen, respectively. In clinical experiment, 0.2-0.3 ml (0.5-0.8 mci) of the 99mTc-plo was injected subcutaneously into the toes web of patients. Half an hour later, the lymph nodes of inguinal, external iliac and common iliac regions appeared in sequence. If the new agent is injected perianally, the internal iliac lymph nodes will be seen. No side effect was observed in both types of experiment. This new agent has been tried in rats, rabbits and dogs with similar positive results. The new lymph node imaging technique is simple, safe, reliable and reproducible. This agent, being directed toward the lymph nodes and possessing affinity to cancer cells, is expected to be supplementary method to CT and B-ultrasonography for detecting lymphoid malignancy and lymph node metastasis. PMID:3248482

  16. Bone metastasis on Tc99-m sestamibi myocardial perfusion scan

    PubMed Central

    Hatemi, Lachin; Jabi, Feraas

    2015-01-01

    A 75-year-old woman presented to our department for a stress myocardial perfusion imaging study with Tc99m-sestamibi. Incidental focal uptake, found in the left upper anterior chest, was initially felt to be located in the left breast. After additional single-photon CT imaging was performed the same day, extracardiac foci within the ribs, spine, and left lung (worrisome for active metastases) were shown to be present, with the initial focus located within a left rib rather than a breast. A review of previous radiographic and nuclear imaging studies confirmed metastatic disease from recurrent follicular thyroid cancer. Atypical focal extracardiac activity must be closely scrutinized for the possibility of malignancy, as Tc99m-sestamibi (in addition to being myocardium-avid) is tumor-avid.

  17. Tc-99m HIDA scintigraphy in segmental biliary obstruction

    SciTech Connect

    Zeman, R.K.; Gold, J.A.; Gluck, L.; Caride, V.J.; Burrell, M.; Hoffer, P.B.

    1981-05-01

    Segmental biliary obstruction as a result of primary or secondary hepatic malignancy has been reported with increasing frequency. For two representative patients, the clinical and Tc-99m HIDA scintigraphic findings in segmental biliary obstruction are described. The presence of photon-deficient dilated bile ducts in one segment of the biliary tree is highly suggestive of localized biliary obstruction and should be considered in the patient with suspected or proven hepatic malignancy despite the absence of jaundice.

  18. Tc-99m HIDA scintigraphy in segmental biliary obstruction

    SciTech Connect

    Zeman, R.K.; Gold, J.A.; Gluck, L.; Caride, V.J.; Burrell, M.; Hoffer, P.B.

    1981-05-01

    Segmental biliary obstruction as a result of primary or secondary hepatic malignancy has been reported with increasing frequency. For two representative patients, the clinical and Tc-99m HIDA scintigraphic findings in segmetal biliary obstruction are described. The presence of photon-deficient dilated bile ducts in one segment of the biliary tree is highly suggestive of localized biliary obstruction and should be considered in the patient with suspected or proven hepatic malignancy despite the absence of jaundice.

  19. Tc-99m pyrophosphate myocardial scanning in Chagas' disease

    SciTech Connect

    da Rocha, A.F.; Meguerian, B.A.; Harbert, J.C.

    1981-04-01

    Chagas' disease is a serious protozoan infection affecting up to 20% of populations in some endemic areas. Myocarditis and cardiomyopathy occur in 50% of patients who go on to develop chronic Chagas' disease. We have studied a patient with no overt cardiac symptoms who revealed intense myocardial uptake of Tc-99m pyrophosphate. The significance of this finding in relation to early detection and progress of therapy is explored.

  20. Tc-99m pyrophosphate myocardial scanning in Chagas' disease

    SciTech Connect

    Goncalves da Rocha, A.F.; Meguerian, B.A.; Harbert, J.C.

    1981-04-01

    Chagas' disease is a serious protozoan infection affecting up to 20% of populations in some endemic areas. Myocarditis and cardiomyopathy occur in 50% of patients who go on to develop chronic Chagas's disease. We have studied a patient with no overt cardiac symptoms who revealed intense myocardial uptake of Tc-99m pyrophosphate. The significance of this finding in relation to early detection and progress of therapy is explored.

  1. Chemical breakdown of technetium-99m DTPA during nebulization

    SciTech Connect

    Waldman, D.L.; Weber, D.A.; Oberdoerster, G.D.; Drago, S.R.; Utell, M.J.; Hyde, R.W.; Morrow, P.E.

    1987-03-01

    Aerosols of /sup 99m/Tc diethylenetriaminepentaacetic acid ((/sup 99m/Tc)DTPA) used for measuring lung permeability and lung ventilation require a radioaerosol delivery system to produce an aerosol with reproducible size and radiochemical purity. To test how well nebulizers meet this requirement, radiochemical purity of aerosols produced with a jet and an ultrasonic nebulizer was evaluated. The activity median aerodynamic diameter (AMAD) and geometric standard deviation (sigma g) of radioaerosols were 0.46 micron (sigma g = 1.6) for the jet nebulizer and 0.70 micron (sigma g = 1.7) for the ultrasonic nebulizer. Paper and liquid chromatographic assays were obtained on the (/sup 99m/Tc)DTPA aerosol solute produced with each nebulizer. The results of these tests showed major differences in radiochemical purity. Aerosols produced in the jet nebulizer consistently showed greater than 90% of the radioactivity bound to the DTPA ligand whereas aerosols produced in the ultrasonic nebulizer showed less than 10% of the radioactivity bound to DTPA. The results support the need to test radiochemical purity of aerosols before using an aerosol nebulizer for pulmonary imaging and clearance studies.

  2. Extramedullary Pulmonary Hematopoiesis Causing Pulmonary Hypertension and Severe Tricuspid Regurgitation Detected by Technetium-99m Sulfur Colloid Bone Marrow Scan and Single-Photon Emission Computed Tomography/CT

    PubMed Central

    Clarke, Michael John; Kannivelu, Anbalagan; Chinchure, Dinesh; Srinivasan, Sivasubramanian

    2014-01-01

    Extramedullary pulmonary hematopoiesis is a rare entity with a limited number of case reports in the available literature only. We report the case of a 66-year-old man with known primary myelofibrosis, in whom a Technetium-99m sulfur colloid bone marrow scan with single-photon emission computed tomography (SPECT)/CT revealed a pulmonary hematopoiesis as the cause of pulmonary hypertension and severe tricuspid regurgitation. To the best of our knowledge, this is the first description of Technetium-99m sulfur colloid SPECT/CT imaging in this rare condition. PMID:24843243

  3. Impact of Multiple Negative Charges on Blood Clearance and Biodistribution Characteristics of 99mTc-Labeled Dimeric Cyclic RGD Peptides

    PubMed Central

    2015-01-01

    This study sought to evaluate the impact of multiple negative charges on blood clearance kinetics and biodistribution properties of 99mTc-labeled RGD peptide dimers. Bioconjugates HYNIC-P6G-RGD2 and HYNIC-P6D-RGD2 were prepared by reacting P6G-RGD2 and P6D-RGD2, respectively, with excess HYNIC-OSu in the presence of diisopropylethylamine. Their IC50 values were determined to be 31 ± 5 and 41 ± 6 nM, respectively, against 125I-echistatin bound to U87MG glioma cells in a whole-cell displacement assay. Complexes [99mTc(HYNIC-P6G-RGD2)(tricine)(TPPTS)] (99mTc-P6G-RGD2) and [99mTc(HYNIC-P6D-RGD2)(tricine)(TPPTS)] (99mTc-P6D-RGD2) were prepared in high radiochemical purity (RCP > 95%) and specific activity (37–110 GBq/μmol). They were evaluated in athymic nude mice bearing U87MG glioma xenografts for their biodistribution. The most significant difference between 99mTc-P6D-RGD2 and 99mTc-P6G-RGD2 was their blood radioactivity levels and tumor uptake. The initial blood radioactivity level for 99mTc-P6D-RGD2 (4.71 ± 1.00%ID/g) was ∼5× higher than that of 99mTc-P6G-RGD2 (0.88 ± 0.05%ID/g), but this difference disappeared at 60 min p.i. 99mTc-P6D-RGD2 had much lower tumor uptake (2.20–3.11%ID/g) than 99mTc-P6G-RGD2 (7.82–9.27%ID/g) over a 2 h period. Since HYNIC-P6D-RGD2 and HYNIC-P6G-RGD2 shared a similar integrin αvβ3 binding affinity (41 ± 6 nM versus 31 ± 5 nM), the difference in their blood activity and tumor uptake is most likely related to the nine negative charges and high protein binding of 99mTc-P6D-RGD2. Despite its low uptake in U87MG tumors, the tumor uptake of 99mTc-P6D-RGD2 was integrin αvβ3-specific. SPECT/CT studies were performed using 99mTc-P6G-RGD2 in athymic nude mice bearing U87MG glioma and MDA-MB-231 breast cancer xenografts. The SPECT/CT data demonstrated the tumor-targeting capability of 99mTc-P6G-RGD2, and its tumor uptake depends on the integrin αvβ3 expression levels on tumor cells and neovasculature. It was concluded that

  4. The determination of relative renal function in a pediatric population using Tc-99m DTPA and Tc-99m DMSA

    SciTech Connect

    Rosen, P.R.; Kuruc, A.; Treves, S.T.

    1985-05-01

    Three methods for evaluating relative renal function in a pediatric population were compared. The clinical and nuclear medicine data of 73 patients were reviewed. Pertinent data included patient age, serum creatinine and the referral diagnosis (reflux, hypertension, obstructive uropathy). Time activity curves for renal regions of interest (ROI) were obtained by renography with Tc-99m DTPA, and deconvolved by an externally detected blood pool curve Furosemide was then administered to evaluate the renal collecting system (if indicated). This was followed by DMSA administration. Relative function was determined in 3 ways: 1) Accumulated renal DTPA activity 60-120 sec. following injection. 2) Amplitude of the tubular phase of the deconvolved renal curve and, 3) Accumulated Tc-99m DMSA activity in renal ROI 4 or 24 hrs. post-injection. Regression analysis revealed: 1) The basic relationship of relative functional data obtained by all three methods was not affected by creatinine, age or other factors. 2) The relationship between the three methods is linear and highly correlated. 3) The DMSA values may be predicted from either method of analyzing the DTPA study using appropriate predictor equations. The authors conclude that Tc-99m DMSA, due to its higher cost and more radiation exposure should not be used for the routine evaluation of relative renal function.

  5. Introduction of an 8-Aminooctanoic Acid Linker Enhances the melanoma uptake of Tc-99m-labeled Lactam Bridge-Cyclized Alpha-MSH Peptide

    PubMed Central

    Guo, Haixun; Miao, Yubin

    2015-01-01

    The purpose of this study was to examine the effects of amino acid, hydrocarbon and polyethylene glycol (PEG) linkers on melanoma targeting and imaging properties of 99mTc-labeled lactam bridge-cyclized HYNIC-linker-Nle-CycMSHhex {hydrazinonicotinamide-linker-Nle-c[Asp-His-DPhe-Arg-Trp-Lys]-CONH2} peptides. Methods four novel peptides {HYNIC-GGGNle-CycMSHhex, HYNIC-GSGNle-CycMSHhex, HYNIC-PEG2Nle-CycMSHhex and HYNIC-AocNle-CycMSHhex} were designed and synthesized. The melanocortin-1 (MC1) receptor binding affinities of the peptides were determined in B16/F1 melanoma cells. The biodistribution of 99mTc(EDDA)-HYNIC-GGGNle-CycMSHhex, 99mTc(EDDA)-HYNIC-GSGNle-CycMSHhex, 99mTc(EDDA)-HYNIC-PEG2Nle-CycMSHhex and 99mTc(EDDA)-HYNIC-AocNle-CycMSHhex were determined in B16/F1 melanoma-bearing C57 mice at 2 h post-injection to select a lead peptide for further evaluation. The melanoma targeting and imaging properties of 99mTc(EDDA)-HYNIC-AocNle-CycMSHhex were further examined because of its high melanoma uptake. Results The IC50 values of HYNIC-GGGNle-CycMSHhex, HYNIC-GSGNle-CycMSHhex, HYNIC-PEG2Nle-CycMSHhex, and HYNIC-AocNle-CycMSHhex were 0.7 ± 0.1, 0.8 ± 0.09, 0.4 ± 0.08, and 0.3 ± 0.06 nM in B16/F1 melanoma cells, respectively. Among these four 99mTc-labeled peptides, 99mTc(EDDA)-HYNIC-AocNle-CycMSHhex displayed the highest melanoma uptake (22.3 ± 1.72% ID/g) at 2 h post-injection. 99mTc(EDDA)-HYNIC-AocNle-CycMSHhex exhibited high tumor to normal organ uptake ratios except for the kidneys. The tumor/kidney uptake ratios of 99mTc(EDDA)-HYNIC-AocNle-CycMSHhex were 3.29, 3.63 and 6.78 at 2, 4 and 24 h post-injection. The melanoma lesions were clearly visualized by single photon emission computed tomography (SPECT)/CT using 99mTc(EDDA)-HYNIC-AocNle-CycMSHhex as an imaging probe at 2 h post-injection. Conclusion High melanoma uptake and fast urinary clearance of 99mTc(EDDA)-HYNIC-AocNle-CycMSHhex highlighted its potential for metastatic melanoma detection in the future

  6. Production of Multimeric Prostate-Specific Membrane Antigen Small Molecule Radiotracers using a Solid-Phase 99mTc Pre-Loading Strategy

    PubMed Central

    Misra, Preeti; Humblet, Valerie; Pannier, Nadine; Maison, Wolfgang; Frangioni, John V.

    2008-01-01

    Small molecule ligands specific for prostate-specific membrane antigen (PSMA) have the potential to improve prostate cancer imaging. However, highly charged ligands are difficult to label with 99mTc and to purify. In this study, we present an adamantane-trimerized small molecule that has nanomolar binding to PSMA, but that also has 12 negative charges. Methods To convert this molecule into a clinically viable SPECT diagnostic, we have developed a simple, cartridge-based, solid-phase pre-labeling strategy that, within 25 minutes, converts readily available and inexpensive 99mTc-pertechnetate into a chemically pure complex, with a reactive N-hydroxysuccinimide (NHS) ester, in neat organic solvent. This stable intermediate can label any amine-containing small molecule or peptide with 99mTc in one step, with high specific activity, and without the need for HPLC. Results Solid-phase conversion of 99mTc-pertechnetate to 99mTc-MAS3-NHS could be completed in 25 minutes, with >99% radiochemical purity and with no co-ligands present. This intermediate was then conjugated to adamantane-trimerized GPI in one step with >95% yield, and no need for HPLC purification. The final molecule bound specifically to living human tumor cells expressing PSMA on their surface. Quantitative comparison was made among GPI monomer, GPI trimer, and their 99mTc derivatives. Conclusion Our study describes a simple cartridge-based conversion of 99mTc pertechnetate to a useful, pre-loaded NHS ester intermediate that takes only 25 minutes to prepare and results in >99% radiochemical purity. Using this chemistry, we produce a high specific activity, 99mTc-labeled, PSMA-targeted small molecule, and demonstrate gamma ray radioscintigraphic imaging of living human prostate cancer cells. PMID:17631555

  7. PET/CT-Based Dosimetry in 90Y-Microsphere Selective Internal Radiation Therapy: Single Cohort Comparison With Pretreatment Planning on 99mTc-MAA Imaging and Correlation With Treatment Efficacy

    PubMed Central

    Song, Yoo Sung; Paeng, Jin Chul; Kim, Hyo-Cheol; Chung, Jin Wook; Cheon, Gi Jeong; Chung, June-Key; Lee, Dong Soo; Kang, Keon Wook

    2015-01-01

    Abstract 90Y PET/CT can be acquired after 90Y-microsphere selective radiation internal therapy (SIRT) to describe radioactivity distribution. We performed dosimetry using 90Y-microsphere PET/CT data to evaluate treatment efficacy and appropriateness of activity planning from 99mTc-MAA scan and SPECT/CT. Twenty-three patients with liver malignancy were included in the study. 99mTc-MAA was injected during planning angiography and whole body 99mTc-MAA scan and liver SPECT/CT were acquired. After SIRT using 90Y-resin microsphere, 90Y-microsphere PET/CT was acquired. A partition model (PM) using 4 compartments (tumor, intarget normal liver, out-target normal liver, and lung) was adopted, and absorbed dose to each compartment was calculated based on measurements from 99mTc-MAA SPECT/CT and 90Y-microsphere PET/CT, respectively, to be compared with each other. Progression-free survival (PFS) was evaluated in terms of tumor absorbed doses calculated by 99mTc-MAA SPECT/CT and 90Y-microsphere PET/CT results. Lung shunt fraction was overestimated on 99mTc-MAA scan compared with 90Y-microsphere PET/CT (0.060 ± 0.037 vs. 0.018 ± 0.026, P < 0.01). Tumor absorbed dose exhibited a close correlation between the results from 99mTc-MAA SPECT/CT and 90Y-microsphere PET/CT (r = 0.64, P < 0.01), although the result from 99mTc-MAA SPECT/CT was significantly lower than that from 90Y-microsphere PET/CT (135.4 ± 64.2 Gy vs. 185.0 ± 87.8 Gy, P < 0.01). Absorbed dose to in-target normal liver was overestimated on 99mTc-MAA SPECT/CT compared with PET/CT (62.6 ± 38.2 Gy vs. 45.2 ± 32.0 Gy, P = 0.02). Absorbed dose to out-target normal liver did not differ between 99mTc-MAA SPECT/CT and 90Y-microsphere PET/CT (P = 0.49). Patients with tumor absorbed dose >200 Gy on 90Y-microsphere PET/CT had longer PFS than those with tumor absorbed dose ≤200 Gy (286 ± 56 days vs. 92 ± 20 days, P = 0.046). Tumor absorbed dose calculated by 99m

  8. Retention of {sup 99m}{Tc}-bicisate in the human brain after intracarotid injection

    SciTech Connect

    Friberg, L.; Lassen, N.A.; Andersen, A.R.; Dam, M.

    1994-01-01

    {sup 99m}{Tc}-bicisate (ECD) was injected as a bolus into the internal carotid artery, and cerebral uptake and retention were recorded with fast-rotating single photon emission computed tomography (SPECT) equipment in four patients suffering from temporal lobe epilepsy. Quantitative regional cerebral blood flow (rCBF) was measured tomographically with the {sup 133}Xe inhalation technique. The authors applied a three-compartment kinetic model and algorithms modified from a previous analysis of {sup 99m}{Tc} d,l-hexamethylpropyleneamine oxide (HM-PAO) kinetics. The bicisate brain uptake and retention curve was very similar to that of HM-PAO, and it can be described by a triexponential function including an initial steep component representing the vascular transmitted spike, a second less steep component representing back-diffusion from brain tissue to blood, and a third, very slow component, representing the very slow loss due to incomplete retention of the deesterified hydrophilic metabolites. Computerized curve-fitting on data from three patients gave average kinetic values for the first-passage (unilateral) extraction of E = 0.60 (range, 0.59-0.61); the overall retained fraction of the tracer supplied was R = 0.44 (0.43-0.45), and the conversion/clearance ratio was {alpha} = k{sub 3}/k{sub 2} = 2.59 (2.38-2.77). This {alpha} is higher than that for HM-PAO, and therefore bicisate uptake as a function of blood flow is more linear than in HM-PAO. Less correction for backdiffusion is therefore needed. From 1 to 24 h there was an average loss of hydrophilic tracer of 3.5%/h, but the late distribution images were essentially unchanged over time, pointing to practically the same rate of loss in all regions. 18 refs., 5 figs., 2 tabs.

  9. Detection of obstructive uropathy using 99m technetium diethylenetriaminepentaacetic acid

    SciTech Connect

    Powers, T.A.; Grove, R.B.; Bauriedel, J.K.; Orr, S.C.; Melton, R.E.; Bowenn, R.D.

    1980-11-01

    A simple, accurate test with no morbidity and effective for the detection of urinary tract obstruction in patients with normal and impaired renal function would be of significant clinical use. The ability of 99m technetium diethylenetriaminepentaacetic acid to detect the presence or absence of obstruction is evaluated. Obstructions were defined as abnormal retention of activity in the collecting system persisting in the delayed images. Diethylentriaminepentaacetic acid identified correctly 13 of 13 patients proved to have obstruction and 17 of 18 without obstruction. These data indicate a sensitivity of 100 percent, specificity of 94 percent and accuracy of 97 percent.

  10. 99mTechnetium Sestamibi-123Iodine Scintigraphy Is More Accurate Than 99mTechnetium Sestamibi Alone before Surgery for Primary Hyperparathyroidism

    PubMed Central

    Ryhänen, Eeva M.; Schildt, Jukka; Heiskanen, Ilkka; Väisänen, Mika; Ahonen, Aapo; Löyttyniemi, Eliisa; Schalin-Jäntti, Camilla; Välimäki, Matti J.

    2015-01-01

    Objectives. Studies comparing outcome of single-99mTc-methoxyisobutylisonitrile (99mTc-sestamibi) and dual-tracer 99mTc-sestamibi scintigraphy in combination with 123I before primary surgery of primary hyperparathyroidism (PHPT) are scarce. Methods. We compared 99mTc-sestamibi/123I and 99mTc-sestamibi in a single-centre retrospective series of 269 PHPT patients. The results were related to laboratory, surgical and histological findings. Results. 99mTc-sestamibi/123I and 99mTc-sestamibi were positive in 206 (76.6%) and 111 (41.3%) of 269 patients, respectively (P < 0.001). Accuracies for 99mTc-sestamibi/123I and 99mTc-sestamibi were 63.4% and 34.9%, respectively (96% CI, P < 0.001). Prevalence of multiglandular disease was 15.2%. In multiglandular disease, 99mTc-sestamibi/123I and 99mTc-sestamibi revealed 43.8 and 22.1% of pathological glands, respectively (P < 0.001). Cure rate was similar for patients with (191/206; 92.7%) and without (59 of 63; 93.7%) a positive 99mTc-sestamibi/123I finding. Duration of targeted surgery (one or two quadrants) was 21 and 15 minutes shorter than bilateral neck exploration, respectively (both P < 0.001). Higher serum calcium (P = 0.014) and PTH (P = 0.055) concentrations and larger tumours (P < 0.001) characterized the 206 patients with a positive preoperative scan who were cured by removal of a single adenoma. Conclusions. 99mTc-sestamibi/123I scintigraphy is more accurate than 99mTc-sestamibi before surgery of PHPT. However, outcome of surgery is not determined by scintigraphy alone. PMID:25722888