Search

Background An assessment of cardiac events and survival using quantitative gated myocardial single-photon emission computed tomography (SPECT) (J-ACCESS) associated several risk factors with cardiac events in Japan. The clinical course after revascularization and/or optimal medical therapy (OMT) was followed in patients with coronary artery disease (CAD) at moderate-to-high risk estimated by software incorporating the J-ACCESS risk model. The present study aimed to determine the relevance of changes in estimated risk to outcomes of these therapies. Methods This study included 494 patients with possible or definite CAD who underwent initial pharmacological stress 99mTc-tetrofosmin myocardial perfusion SPECT (MPS) before and eight months after therapy. Major cardiac event risk during 3 years of follow-up was calculated using an equation based on that in the J-ACCESS study. Patients with ≥ 10% cardiac event risk estimated at the first MPS (n = 31) were analyzed and followed up for at least 1 year. Results Estimated risk was reduced by ≥ 5% in 14 patients (45%) after therapy. During a follow-up period of 22.1 ± 6.7 months, one patient without such reduction had a major cardiac event. Mean %summed stress scores significantly decreased from baseline to follow-up in patients with and without risk reduction. Left ventricular ejection fraction (LVEF [%]) at rest was significantly increased at the second, compared with the first MPS between patients with, than without risk reduction (57 ± 17 vs. 45 ± 16%, p = 0.001 and 50 ± 11 vs. 49 ± 9%, p = 0.953, respectively). Conclusions A reduction in cardiac ischemia and an increase in LVEF by revascularization and/or OMT were necessary to avoid cardiac events among patients with moderate-to-high estimated risk, and changes in event risk were quantifiable.

Background: The goal of this study was to evaluate the prevalence of depression and anxiety in patients subjected to myocardial perfusion imaging (MPI) with 99mTc tetrofosmin stress-rest single-photon emission computer tomography (SPECT), and their impact on their cardiological events or disease. Material and Methods: Patients referred to the Nuclear Medicine Department for 99mTc tetrofosmin myocardial MPI-SPECT were asked to fulfill the Zung Self-Rating Depression Scale (ZDS) and Hamilton anxiety questionnaire (HAQ). Among 213 patients who completed the ZDS and HAQ, 80 patients (59 males and 21 females) were selected for this study because they had no known psychological disease, other disease that could influence psychological status, or use of narcotic drugs. Collected data from MPI and psychological status were subsequently analyzed. Results: Among all 80 patients, 52 patients (65%) had abnormal MPI of whom 28/52 (53.8%) exhibited either depression, anxiety or both, and 28 (35%) patients had normal MPI of whom 10/28 (35.7%) had abnormal psychological status. The higher number of patients with abnormal psychological status in association with abnormal MPI was noted predominantly in patients with previously established coronary artery disease. A correlation was also noted between obesity, cardiac heredity and depression or anxiety in patients with abnormal MPI. Conclusions: Patients that exhibit depression, anxiety, or both, have high rates of myocardial ischemia, and thus are at risk for subsequent cardiological events.

Measurement of myocardial blood flow (MBF) is feasible using SPECT imaging but the acquisition requires more time than usual. Our study assessed the impact of reducing acquisition times on the accuracy and repeatability of the uptake rate constant (K1). Twenty-nine patients underwent two rest/stress studies with Tc-99m-tetrofosmin 18 ± 13 days apart, using a one-day rest/stress dynamic SPECT imaging protocol with a solid-state cardiac camera. A 5-minute static image was acquired prior to tracer injection for subtraction of residual activity, followed immediately by 11-minute of list-mode data collection. Static image acquisition times of 0.5, 1, and 3 minutes and dynamic imaging times of 5, 7, and 9 minutes were simulated by truncating list-mode data. Images were reconstructed with/without attenuation correction and with/without motion correction. Kinetic parameters were calculated using a 1-tissue-compartment model. K1 increased with reduced dynamic but not static imaging time (P 0.17). A shortened imaging protocol of 3-minute (rest) or 30-second (stress) static image acquisition and 9 minutes of dynamic image acquisition altered K1 by less than 5% compared to a previously validated 11-minute acquisition.

PET/CT is the standard for quantitative assessments of myocardial blood flow (MBF), but it requires short-lived-tracers, costly, and not widely available. SPECT with Cadmium Zinc Telluride (CZT) detectors allows dynamic acquisition and quantitation of MBF. The study aims were to compare MBF measurements by 99mTc-tetrofosmin-CZT to N13NH3 PET/CT after regadenoson-induced coronary hyperemia and to evaluate the effect of attenuation correction (AC). 54 patients were evaluated at rest and during vasodilation by 99mTc-tetrofosmin-CZT and N13NH3 PET/CT within 2 weeks. MBF and MBF reserve (MFR) were measured by CZT with or without AC (NAC). The global rest MBF was 0.76 ± 0.19 mL/min/gr by PET and 0.76 ± 0.24 by AC-CZT (P = NS) and 1.14 ± 0.4 by NAC-CZT (P < 0.001 vs PET and AC-CZT). Stress MBF was higher when measured by PET than AC-CZT (1.87 ± 0.45 vs 1.62 ± 0.68 mL/min/gr, P < 0.0008), but lower than NAC-CZT (2.36 ± 1.1, P < 0.0003). The MBF reserve ratio (MFR) was higher by PET than AC-CZT (2.52 ± 0.56 vs 2.22 ± 1 (P < 0.009) and NAC-CZT (2.18 ± 1.0, P < 0.004). Linear regression was better between PET (MFR and stress MBF) and AC-CZT than between PET and NAC-CZT. ROC curve analysis showed the significant ability of AC-CZT to predict MFR < 2 and stress MBF < 1.7 (AUC = 0.75 and 0.82 respectively) and to differentiate between normal and CAD patients (AUC = 0.747 and 0.892 for MFR and stress MBF, respectively). Our data show a reasonable correlation between MBF and MFR measured by N13NH3-PET and 99mTc-Tetrofosmin-CZT SPECT. NAC-CZT overestimates MBF. AC is recommended when using CZT for measuring MBF.

The accumulation of high levels of 99mTc-tetrofosmin (99mTc-TF) in the hepatobiliary system can lead to imaging artifacts and interference with diagnosis. The present study investigated the transport mechanisms of 99mTc-TF and attempted to apply competitive inhibition using a specific inhibitor to reduce 99mTc-TF hepatic accumulation. In this in vitro study, 99mTc-TF was incubated in HEK293 cells expressing human organic anion transporting polypeptide 1B1 (OATP1B1), OATP1B3, OATP2B1, organic anion transporter 2 (OAT2), organic cation transporter 1 (OCT1), OCT2, and Na+-taurocholate cotransporting polypeptide with or without each specific inhibitor to evaluate the contribution of each transporter to 99mTc-TF transportation. In vivo studies, dynamic planar imaging, and single photon emission computed tomography (SPECT) experiments with rats were performed to observe alterations to 99mTc-TF pharmacokinetics using cimetidine (CMT) as an OCT1 inhibitor. Time–activity curves in the liver and heart were acquired from dynamic data, and the 99mTc-TF uptake ratio was calculated from SPECT. From the in vitro study, 99mTc-TF was found to be transported by OCT1 and OCT2. When CMT-preloaded rats and control rats were compared, the hepatic accumulation of the 99mTc-TF was reduced, and the time to peak heart count shifted to an earlier stage. The hepatic accumulation of 99mTc-TF was markedly suppressed, and the heart-to-liver ratio increased 1.6-fold. The pharmacokinetics of 99mTc-TF were greatly changed by OCT1 inhibitor. Even in humans, the administration of OCT1 inhibitor before cardiac SPECT examination may reduce 99mTc-TF hepatic accumulation and contribute to the suppression of artifacts and the improvement of SPECT image quality., Pharmaceutics, 13(7), art. no. 1073; 2021

Myocardial perfusion scintigraphy (MPS) is based on visual qualitative interpretation and hence interobserver variability might affect clinical decision-making for the patient. Quantification of single photon emission computed tomography (SPECT) imaging enables absolute measurement of treatment efficacy. The aim of this experimental study is to assess quantitative accuracy and precision of iterative image reconstruction (Evolution; Q.Metrix package; GE Healthcare, Little Chalfont, UK), making use of both phantom and patient studies, for potential application of 99mTc-tetrofosmin SPECT/CT in coronary artery disease (CAD) patients. This research consists of a phantom study and an experimental validation study with patient data. An anthropomorphic torso phantom with cardiac insert was filled with technetium (99mTc) and acquired on a SPECT/CT gamma (Discovery 670 Pro; GE Healthcare). Seven sets of 6 acquisitions were evaluated containing a cardiac insert with various defect sizes and configurations. Subsequently, volumes‐of‐interest of the defects were manually drawn on CT to assess the recovery coefficient (RC). Bull’s eye plots were composed to evaluate the uptake per segment. Finally, 99mTc-tetrofosmin SPECT/CT scans were collected retrospectively in ten CAD patients after bone marrow cell treatment and evaluated using Evolution. The phantom study shows that the activity concentration converged after seven iterations (ten subsets) using Evolution. SPECT/CT data were reconstructed with and without Butterworth post-filtering. The average repeatability deviation of all configurations was 2.66% and 2.90% (%SD mean) for the filtered and unfiltered data, respectively. The accuracy after Butterworth post-filtering was lower compared to the unfiltered data with a mean(SD) RC of 0.66 ± 0.06 and 0.71 ± 0.05, respectively (p

Funding Acknowledgements Type of funding sources: None. Introduction Cardiac 123I-mIBG SPECT imaging provides information on regional myocardial innervation. However, there is no consensus on how to use a, 17-segment based score to assess prognosis. The present study examined whether a simpler regional scoring approach for evaluation of 123I-mIBG SPECT combined with rest 99mTc-tetrofosmin SPECT myocardial perfusion imaging could be used for the prediction of arrhythmic events (AEs) in ischemic heart failure (HF). Methods 261 ischemic HF subjects (NYHA II/III, LVEF ≤35% on gated SPECT) of the ADMIRE-HF study cohort with complete cardiac 123I-mIBG and rest 99mTc-tetrofosmin SPECT studies were enrolled. Both SPECT image sets were read together by 2 experienced nuclear imagers and scored by consensus. In addition to standard 17 segments scoring, the readers classified walls (i.e. anterior, lateral, inferior, septum and apex) as normal, matched defect of innervation and perfusion, mismatched (i.e., innervation defect lager than perfusion defect) or reverse mismatched (i.e., innervation defect smaller than perfusion defect). Cox proportional hazards ratios (HR) were used to determine if the visual segmental wall classification innervation/perfusion mismatch score, 123I-mIBG summed defect scores (SDS), 99mTc-tetrofosmin SDS and innervation/perfusion mismatch SDS, age, LVEF, NYHA class, B-type natriuretic peptide (BNP) and norepinephrine (NE) plasma levels were associated with occurrence of AEs (i.e. sudden cardiac death, sustained VT, resuscitated cardiac arrest, appropriate ICD therapy). Results At 2-year median follow-up, 38 subjects (14.6%) had AEs. Subjects with 1 or 2 mismatched walls were more than twice as likely to have AEs compared with subjects with either 0 or 3-5 mismatched walls (24.0% vs 10.8%, p = 0.006). Cox regression analyses showed that the combination of the presence of visual mismatch in 1-2 walls and BNP and were the only independent predictors of AEs (HR 2.583 [1.261-5.107],p = 0.001) However, compared to the visual mismatch, the contribution of BNP is relatively small (i.e., HR 1.001 [1.000-1.001]). Conclusion In ischemic HF with LVEF ≤35 the highest risk of AEs occurs in subjects with intermediate levels of visual wall-level innervation/perfusion mismatches. Therefore, a simple visual wall-level based assessment of combined cardiac 123I-mIBG and rest 99mTc-tetrofosmin SPECT can be used to differentiate those HF patients at higher AE risk from those with relatively low AE risk. Table 1. Cox regression analysis Variable HR (95% CI) X2 change X2 p-value AE’s 1-2 mismatched segments 2.412 (1.204-4.830) 6.581 5.880 0.010 BNP 1-2 mismatched segments 1.001 (1.000-1.001) 2.538 (1.261-5.107) 13.434 4.129 0.001 Abstract Figure. Kaplan Meier curves for AEs

Purpose In this prospective study we compared the accuracy of 18F-fluorocholine PET/CT with that of 99mTc-MIBI or99mTc-tetrofosmin SPECT/CT in the preoperative detection of parathyroid adenoma in patients with primary hyperparathyroidism. We also assessed the value of semiquantitative parameters in differentiating between parathyroid hyperplasia and adenoma. Methods Both 18F-fluorocholine PET/CT and 99mTc-MIBI/tetrofosmin SPECT/CT were performed in 100 consecutive patients with biochemical evidence of primary hyperparathyroidism. At least one abnormal focus on either 18F-fluorocholine or 99mTc-MIBI/tetrofosmin corresponding to a parathyroid gland or ectopic parathyroid tissue was considered as a positive finding. In 76 patients with positive findings on at least one imaging modality, surgical exploration was performed within 6 months, and the results were related to histopathological findings and clinical and laboratory findings at 3–6 months as the standard of truth. In 24 patients, no surgery was performed: in 18 patients with positive imaging findings surgery was refused or considered risky, and in 6 patients imaging was negative. Therefore, data from 82 patients (76 undergoing surgery, 6 without surgery) in whom the standard of truth criteria were met, were used in the final analysis. Results All patients showed biochemical evidence of primary hyperparathyroidism with a mean serum calcium level of 2.78 ± 0.34 mmol/l and parathormone (PTH) level of 196.5 ± 236.4 pg/ml. The study results in 76 patients with verified histopathology and 3 patients with negative imaging findings were analysed. Three of six patients with negative imaging showed normalized serum PTH and calcium levels on laboratory follow-up at 3 and 6 months, and the results were considered true negative. In a patient-based analysis, the detection rate with 18F-fluorocholine PET/CT was 93% (76/82), but was only 61% (50/82) with 99mTc-MIBI/tetrofosmin SPECT/CT. In a lesion-based analysis, the sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of 18F-fluorocholine PET/CT in the detection of parathyroid adenoma were 93.7%, 96.0%, 90.2%, 97.4% and 95.3%, respectively, and of 99mTc-MIBI/tetrofosmin SPECT/CT were 60.8%, 98.5%, 94.1%, 86.3% and 87.7%, respectively. Although 18F-fluorocholine PET-positive adenomatous lesions showed higher SUVmax values than the hyperplastic glands (6.80 ± 3.78 vs. 4.53 ± 0.40) in the semiquantitative analysis, the difference was not significant (p = 0.236). The mean size (measured as the length of the greatest dimension) and weight of adenomas were 15.9 ± 7.6 mm (median 15 mm, range 1–40 mm) and 1.71 ± 1.86 g (median 1 g, range: 0.25–9 g), respectively. Among the analysed parameters including serum calcium and PTH and the size and weight of parathyroid adenomas, size was significantly different between patients with negative 99mTc-MIBI/tetrofosmin SPECT/CT and those with positive 99mTc-MIBI/tetrofosmin SPECT/CT (mean size 13.4 ± 7.6 mm vs. 16.9 ± 7.4 mm, respectively; p = 0.042). Conclusion In this prospective study, 18F-fluorocholine PET/CT showed promise as a functional imaging modality, being clearly superior to 99mTc-MIBI/tetrofosmin SPECT/CT, especially in the detection and localization of small parathyroid adenomas in patients with primary hyperparathyroidism. SUVmax was higher in parathyroid adenomas than in hyperplasia. However, further evaluation of this modality is needed.

Objective: The prevalence of coronary artery disease (CAD) is high in patients with diabetes. Because ischemia and infarction are often silent in diabetic patients, diagnosis of CAD occurs inevitably late. It is essential to identify the presence of CAD in diabetic patients to start early treatment. Therefore, the aim of this study was to determine the prevalence of abnormal myocardial perfusion in asymptomatic type 2 diabetic patients using myocardial perfusion imaging. Methods: Fifty-nine patients with type 2 diabetes, who did not have any history of CAD, but did have risk factors underwent myocardial perfusion single-photon emission computed tomography (SPECT) imaging using 99mTc-tetrofosmin and a 2-day stress–rest protocol. Two nuclear medicine specialists independently interpreted the images. Statistical analysis was performed to determine if there is a correlation between the presence of perfusion abnormalities and the history of diabetes (duration of disease, type of treatment, level of control, and presence and type of complications). The influence of other factors such as age, sex, smoking history, and family history of CAD, with abnormal scans were also studied. Results: Of the 59 patients, abnormal scans were detected in 22 (37%) including 16 with reversible defects due to stress-induced ischemia. Hence the prevalence was 37%. Duration of diabetes, use of insulin, nephropathy, and neuropathy were significantly associated with abnormal scans (p = 0.048, p = 0.045, p = 0.006, and p = 0.03, respectively). Additionally, positive family history of CAD was highly associated with perfusion abnormalities (p

Considered rare disease in the past, primary hyperparathyroidism (PHPT) has dramatically increased in incidence over the past thirty years with the introduction of routine calcium measurements; it is now approximately 42 per 100 000 persons. By far, the most common lesion found in patients with PHPT is the solitary parathyroid adenoma, occurring in 85%-90% of patients, while in the rest 10%- 15% primary hyperplasia of the parathyroid glands is present. Currently, the most widely used surgical approach is minimally invasive parathyroidectomy which is associated with less post-surgery complications and shorter operation time. To be successful this procedure needs to rely on a precise preoperative localization of the abnormal parathyroid glands, hence preoperative parathyroid imaging gained so large importance. The rationale for locating abnormal parathyroid tissue prior to surgery is that the glands can be notoriously unpredictable in their location. There is a general consensus that the best imaging procedure identifying abnormal parathyroid glands is the preoperative scintigraphy with99mTc-sestamibi or99mTc-tetrofosmin. It is characterized with high sensitivity and specificity exceeding those of ultrasound, CT or MRI. Combining scintigraphy with the other imaging techniques increases the precision for topic localization.

Background: Measurement of myocardial blood flow (MBF) with single photon emission computed tomography (SPECT) is feasible using cardiac cameras with solid-state detectors. SPECT MBF has been shown to be accurate when compared with positron emission tomography MBF measured in the same patients. However, the value of a test result applied to an individual patient depends strongly on the precision or repeatability of the test. The purpose of our study is to measure the precision of SPECT MBF measurements using 99m Tc-tetrofosmin and a solid-state cardiac camera. Methods: SPECT MBF was measured in 30 patients and repeated at a mean interval of 18 days. MBF was evaluated from images with and without attenuation correction based on a separately acquired CT scan. The dynamic images were processed independently by 2 operators using in-house kinetic analysis software that applied a 1-tissue-compartment model. The K1 rate constant was converted to MBF using previously determined extraction fraction corrections. Correction for patient body motion was applied manually. Results: The average coefficient of variation (COV) in the differences between the 2 MBF measurements was between 28% and 31%. The interobserver COV was between 11% and 15%. Myocardial flow reserve is the ratio of MBF measured at stress and rest, and the COV is correspondingly higher. The COV for the difference in repeated myocardial flow reserve was 33% to 38%, whereas the interobserver COV was 13% to 22%. Conclusions: The COV for the difference in SPECT MBF measurements obtained on separate days is 28% to 31%. The corresponding COV for myocardial flow reserve is 33% to 38%.

The use of cadmium-zinc-telluride-based scanners may increase the clinical feasibility of simultaneous dual-isotope imaging. In the current study, we sought to investigate a potential acquisition time in simultaneous Tc-tetrofosmin/I-β-methyl-p-iodophenyl pentadecanoic acid dual-isotope imaging using a Discovery NM/CT 670 cadmium-zinc-telluride.Simultaneous Tc-tetrofosmin/I-β-methyl-p-iodophenyl pentadecanoic acid dual-isotope imaging was performed in 29 patients who had undergone primary percutaneous coronary intervention for acute myocardial infarction. Referenced images with an acquisition time of 65 s/view (16.25 min) were reframed to produce images with acquisition times of 33, 16, and 8 s/view. The values for the quantitative-gated single-photon emission computed tomography (SPECT) and the quantitative perfusion SPECT were compared.The quantitative-gated SPECT values for images with 33, 16, and 8 s/views showed good consistency with those for 65 s/view (the lower 95% confidence intervals for the intraclass correlation were ≥0.80). The quantitative perfusion SPECT values for Tc-tetrofosmin images with 33, 16, and 8 s/views also showed good consistency with those for 65 s/view; however, the quantitative perfusion SPECT values for I-β-methyl-p-iodophenyl pentadecanoic acid images with an acquisition time of 8 s/view were not consistent with the reference acquisition time of 65 s/view.The quantitative-gated SPECT and quantitative perfusion SPECT values obtained from images with shorter acquisition times correlated with the values obtained from images with a reference acquisition time of 65 s/view; however, tracer-specific predisposition should be considered. These findings suggest that it is possible to reduce acquisition time when performing simultaneous Tc-tetrofosmin/I-β-methyl-p-iodophenyl pentadecanoic acid dual-tracer imaging with the novel cadmium-zinc-telluride scanner.

99mTc-tetrofosmin (99mTc-TF) is a single-photon emission computed tomography tracer that has been used for brain tumor imaging. The aim of the study was to assess if 99mTc-TF uptake by glioblastoma cells correlates with their response to temozolomide (TMZ). We investigated the correlation of TMZ antitumor effect with the 99mTc-TF uptake in two glioblastoma cell lines. The U251MG cell line is sensitive to TMZ, whereas T98G is resistant. Viability and proliferation of the cells were examined by trypan blue exclusion assay and xCELLigence system. Cell cycle was analyzed with flow cytometry. The radioactivity in the cellular lysate was measured with a gamma scintillation counter. TMZ induced G2/M cell cycle arrest in U251MG cells, whereas there was no effect on cell cycle in T98G cells. Lower 99mTc-TF uptake was observed in U251MG cells that were exposed to TMZ compared to control (P = 0.0159). No significant difference in respect to 99mTc-TF uptake was found in T98G cells when exposed to TMZ compared to control (P = 0.8). With 99mTc-TF, it was possible to distinguish between TMZ-sensitive and resistant glioblastoma cells within 6 h of treatment initiation. Thus, 99mTc-TF uptake may consist a novel approach to assess an early response of glioblastoma to chemotherapy and deserves further investigation.

(99m)Tc-tetrofosmin single photon emission computed tomography ((99m)Tc-tetrofosmin SPECT) has an important role in the assessment of coronary artery disease. Despite being its main indication, this study does not only evaluate myocardial perfusion, but much more. Moreover, during the SPECT acquisition, the field area covered includes many important organs of the thorax and abdomen, so extracardiac abnormalities can be observed. The correct etiologic diagnosis of them is only possible if we understand how (99m)Tc-tetrofosmin works and make a comprehensive investigation of the clinical history of the patient.

This prospective study investigated radiation exposure dose (RED) to main operator (MO) and supervisory operator (SO) performing dypiridamole stress testing in a 1-d rest/stress 99mTc tetrofosmin single-photon emission computed tomography (SPECT) of consecutive 42 patients. MO was instructed to be close to the patients during the entire procedures including the vasodilator and radiotracer injection. SO mainly recorded the data on the procedures apart from the patients. RED, procedure time (PT) and internal radioactivity (IR) of patients were measured before and after a secondary tracer injection for stress SPECT, respectively. RED was significantly greater to MO than to SO (6.2 ± 2.7 vs 2.5 ± 2.1 μSV per stress procedure, p < 0.0001). Multivariate analyses revealed that IR and PT were significantly independent factors to predict RED to both operators. Operators performing pharmacologic stress procedure should be aware that IR and PT are independent factors for RED in 99mTc myocardial perfusion imaging.

Background Exercise 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) is a useful tool for short- and medium-term risk stratifications. Currently, the long-term prognostic application of this technique has not been evaluated. Methods and Results Exercise 99mTc-tetrofosmin was performed in 655 consecutive patients. Ten patients who underwent revascularization

PURPOSE The aim of this study was to assess the relationship between administered 99mTc tetrofosmin activity in myocardial gated-SPECT and findings of myocardial perfusion and left ventricular ejection fraction (LVEF) as markers of diagnostic outcome. MATERIALS AND METHODS Fifty-two patients with heterogeneous cardiac diseases and a clinical referral for myocardial perfusion imaging were prospectively studied. A separate-day acquisition protocol was adopted with a low fixed activity of 370 MBq, which corresponds to an average reduction of 31% with respect to the median value of 533 MBq usually administered in our laboratory. A standard acquisition with a time/frame of 25 seconds was performed (ST). Immediately after the conclusion of the first acquisition, a second acquisition was performed with a high time/frame of 33 seconds (HT), which corresponds to an increase of 31% with respect to standard time/frame adopted in our laboratory. The order of ST and HT acquisitions was randomized in individual patients. The summed stress scores (SSS), the summed rest scores (SRS), the LVEF, and the end-diastolic volume (EDV) were automatically calculated. RESULTS The image quality score was significantly higher in HT than in ST. No significant differences were found in SSS, SRS, LVEF, and EDV between HT and ST SPECT. The agreement between HT and ST was 84% (kw=0.88) in the correct classification of stress images. The agreement between HT and ST was 84% (k=0.70) in the detection of ischemia and scar. The limits of agreement between the HT and the ST methods were roughly within ±3 points for SSS and SRS, ±13% for poststress LVEF, and ±18 mL for poststress EDV. CONCLUSIONS Using about half of the activity recommended by the current diagnostic reference levels for separate-day myocardial perfusion imaging, the present study demonstrates that images may be obtained using ST protocol with quantitative results comparable with those from studies performed using the HT protocol, which is equivalent to an administered activity of 530 MBq. The former protocol would allow for a significant reduction of the dose to the patients as well as to the operators. Further studies are needed to confirm that this dose-sparing approach does not hamper sensitivity and specificity for coronary stenoses.

Differentiating neoplastic from non-neoplastic intracranial lesions is of paramount importance for patient management. Benign lesions can have many of the features of malignant brain tumors on both computed tomography (CT) and conventional magnetic resonance imaging (MRI). Herewith, we set out to investigate the role of (99m)Tc-Tetrofosmin (⁹⁹(m)Tc-TF) brain SPECT in the differentiation of neoplastic from non-neoplastic intracranial lesions. We prospectively studied, between September 2004 and September 2009, patients with intracranial lesions suspected of being tumors on CT/MRI that were operated on. All patients with suspected tumor on CT/MRI underwent ⁹⁹(m)Tc-TF brain SPECT within a week before surgery and CT/MRI studies. Radiotracer accumulation in intracranial lesions was assessed visually and then a semiquantitative method of image analysis was applied, by calculating the lesion-to-normal (L/N) uptake ratio. We compared the L/N ratios between low-grade gliomas and high-grade gliomas, low and high-grade gliomas and intra-axial non-neoplastic lesions, low and high-grade gliomas and metastases, and typical versus anaplastic meningiomas Ninety patients suffered from neoplastic lesions and 16 harboured non-neoplastic pathologies. There was a significant difference between low-grade gliomas and high-grade gliomas (P = 0.0019). ROC analysis provided 2.8 as the optimum cutoff value thresholding discrimination between these two groups, with 91.3% sensitivity and 83.3% specificity. When comparing gliomas (low and high-grade) with intra axial non-neoplastic lesions the difference was statistically significant (P0.0001). There was no statistically significant difference between gliomas (low and high-grade) and metastases. Regarding meningiomas, there was a statistically significant difference between typical and anaplastic meningiomas (P = 0.0002). ROC analysis provided 9.6 as the optimum cutoff value thresholding discrimination between these two groups, with 96% sensitivity and 100% specificity. (99m)Tc-TF brain SPECT may differentiate neoplastic from non-neoplastic intracranial pathologies and could prove useful for pre-surgical evaluation of intracranial lesions.

Early diagnosis and initiating treatment of cardiac sarcoidosis are essential because cardiac involvement is an important prognostic factor. Although there are many reports on the diagnosis of cardiac sarcoidosis, the literature on predicting the efficacy of steroid therapy is very limited. The purposes of this study were to investigate the myocardial washout of (99m)Tc-tetrofosmin (TF), and to evaluate the predictability of left ventricular (LV) functional recovery after steroid therapy in patients with cardiac sarcoidosis.We performed TF-gated SPECT and echocardiography for ten patients with cardiac sarcoidosis before and after initiating steroid therapy. SPECT images were acquired at 30 min (early images) and 3 h (delayed images) after injection. We calculated the total defect score (TDS) and left ventricular ejection fraction (LVEF). The washout score (WOS) was considered as the difference between the early and delayed TDS. In addition, we defined DeltaLVEF as the change in LVEF after initiating steroid therapy. Furthermore, we analyzed the regional TF myocardial uptake (%uptake) and the regional LV function (wall thickness, WT) by the 20-segment model on polar maps as regional indices. The regional washout (RWO) was defined as the change in %uptake between the early and delayed images in TF SPECT before the therapy. We calculated the improvement factor of the regional LV function as DeltaWT (WT after initiating therapy - WT before the therapy) and investigated the relationships among the indices.We observed WO in 6 of 10 patients (60%). Decreased WT on echocardiography was observed in only 2 of 6 patients (33.3%) in the WO(+) group and in all 4 patients (100%) in the WO(-) group (p0.05). WOS before initiating steroid therapy exhibited a good correlation with DeltaLVEF (r = 0.685, p0.05). In the regional analysis, %uptake in the early images and delayed images before therapy did not significantly correlate with DeltaWT. In contrast, RWO before therapy was well correlated with DeltaWT (r = 0.435, p0.05).Our preliminary study shows that there is a relationship between washout of (99m)Tc-tetrofosmin and the LV functional recovery after steroid therapy in patients with cardiac sarcoidosis.

Objectives: Brain single-photon emission computed tomography (SPECT) has been proposed as a potentially useful modality for the metabolic assessment of various brain tumors. Material and methods: In a 10-patient prospective pilot study we evaluated whether (99m)Tc-Tetrofosmin ((99m)Tc-TF) uptake correlates with glioma proliferative activity assessed by flow cytometric analysis. (99m)Tc-TF brain SPECT was performed shortly before surgical tumor excision. Results: Eight patients were diagnosed with glioblastoma multiform and 2 with anaplastic astrocytoma. All tumors were aneuploid. We found a significant positive linear correlation between 99mTc-TF uptake and percentage of tumor cells on the S-phase of the cell cycle (r=0.92, P=0.001). Conclusion: Initial evidence suggests that 99mTc-TF could provide a non-invasive indicator of glioma proliferative activity. (C) 2009 Elsevier B.V. All rights reserved. Clin Neurol Neurosurg

In the early days, hospital radiopharmacy usually fell under the remit of medical physics and regulation was somewhat informal. An early guideline on preparation of radiopharmaceuticals in hospitals was published by the British Institute of Radiology in 1975. With the loss of Crown Immunity in 1991, radiopharmacy came under the full scrutiny of the MHRA and standards have been continually tightened since then. Indeed, the UK led the world in this, for which the world does not thank us. Members of the UK community continue to play an important role nationally and internationally in advancing the practice of hospital radiopharmacy. This chapter explores the evolution of hospital radiopharmacy in the UK.

Gated single-photon emission computed tomography (G-SPECT) was used to evaluate cardiac risk associated with noncardiac surgery and determine the benefits and indications of this technique for this type of surgery.Patients scheduled to undergo noncardiac surgery under the supervision of anesthesiologists and subjected to preoperative cardiac evaluation using G-SPECT during the 26-month period between June 2000 and August 2002 were followed for the presence/absence of cardiac events (i.e., cardiac death, myocardial infarction, unstable angina, congestive heart failure, or fatal arrhythmia) during surgery and the postoperative period until discharged. Relationships between the occurrence of cardiac events and preoperative G-SPECT findings were evaluated.A total of 39 patients underwent G-SPECT; 6 of the 39 exhibited abnormal ejection fraction (left ventricular ejection fraction, LVEFor=50%) and end-systolic volume (ESVor=50 ml). Surgery was suspended for three of these six patients and cardiac events developed in the remaining three patients. Both abnormal perfusion images (PI) and abnormal wall thickening (WT) were observed in all six patients. All six patients exhibited abnormal LVEF and/or ESV. Three patients had either abnormal PI or WT, and a cardiac event occurred in one of them. Of the five patients who experienced cardiac events during or after surgery, two exhibited a short run of ventricular tachycardia requiring a continuous administering of antiarrhythmic drugs, whereas the remaining three patients exhibited cardiac failure requiring inotropic support following surgery.The results of this study indicate that the occurrence of perioperative cardiac events can be predicted by considering the severity of expected surgical stress and preoperative G-SPECT findings for LVEF, PI, and WT. We conclude that G-SPECT is quite useful for cardiac risk assessment in patients undergoing noncardiac surgery.

We evaluated the usefulness of (99m)Tc-tetrofosmin planar scintigraphy acquired with a high-resolution (HR) dedicated breast camera in comparison with conventional single-photon emission computed tomography (SPECT) and pinhole-SPECT (P-SPECT) in breast cancer (BC) axillary lymph node metastasis detection in a consecutive series of 76 BC patients, 28 of whom had axillary lymph node metastases, including 9 positive at clinical examination. HR planar scintigraphy was true positive in only 7 patients with3 palpable metastases (sensitivity: 25%), while SPECT was true positive in 23 of 28 cases (sensitivity: 82.1%) and P-SPECT in 25 of 28 (sensitivity: 89.3%). SPECT was false negative in 5 patients with nonpalpableor= 3 nodes, including 2 with one micrometastatic node, while P-SPECT was false negative in the latter 2 cases, and in another of the cases, false negative at SPECT with one macrometastatic node. Neither planar nor SPECT had false-positive findings (specificity: 100%), while P-SPECT had two (specificity: 95.8%). P-SPECT presented the best resolution in showing the metastatic nodes and was the only procedure able to define the number of involved nodes, thus delivering important prognostic information. HR planar scintigraphy appears an ineffective diagnostic tool in BC axillary lymph node metastasis detection, only succeeding in identifying palpable and3 metastatic nodes. SPECT should be preferred, significantly improving the sensitivity of planar scintigraphy, especially when using a pinhole collimator.

Objectives Myocardial perfusion SPECT is frequently affected by artefacts related to abdominal activity. Metoclopramide has been suggested to relieve this, but two previous studies have shown conflicting results. Methods Ninety-five patients received 10mg metoclopramide orally after injection of 99m Tc-tetrofosmin for the stress scan and 86 patients had metoclopramide after their rest injection. A control group of 82 patients did not receive metoclopramide. Scans were evaluated visually by three readers. Results Metoclopramide given before the stress scan led to abdominal activity being visually better in 16 scans, worse in 10, and unchanged in 67 scans, compared to the same patient's rest scan without metoclopramide administration. Metoclopramide administered before the rest scan resulted in abdominal activity in 11 scans being visually better, in 19 worse, and 53 scans were deemed unchanged. These differences were not significant. The number of repeat stress or rest scans was not significantly different between patients who had received metoclopramide and those who had not. The administration of metoclopramide, irrespective of whether it was given before the stress or rest scan, made no significant difference to inferior wall-to-abdomen count ratio. Conclusion Neither qualitative nor quantitative analysis showed an effect of metoclopramide on abdominal activity in myocardial perfusion SPECT.

Background Coronary artery disease impairs cardiac vasodilatory reserve. A low ratio of cardiac to hepatic vasodilatory reserve may be diagnostic for coronary artery disease. Aim To compare the ratio of cardiac to hepaticuptake of 9 9 m Tc-tetrofosmin during adenosine infusion and at rest in patients with and without coronary artery disease in order to determine whether the ratio was significantly different between the two groups. Methods Fifty-one patients who underwent coronary angiography and adenosine stress myocardial perfusion imaging using 9 9 m Tc-tetrofosmin were studied retrospectively. Anterior planar images from the single photon emission computed tomography (SPECT) raw data were used to draw regions of interest around the heart and liver. The counts per pixel in each region were used to calculate the stress ratio (SR) and the rest ratio (RR) as follows: SR=(cardiac counts per pixel)at s t r e s s /(hepatic counts per pixel) a t stress; RR=(cardiac counts per pixel)at r e s t /(hepatic counts per pixel)at rest. The SR and SR/RR ratios were compared in patients with and without significant coronary artery disease. Receiver operating characteristic curves were drawn for SR and SR/RR. Results The SR and SR/RR ratios were significantly lower in patients with significant coronary artery disease than in patients without (P

99mTc tetrofosmin is predominantly cleared by the hepatobiliary system and its scan is analogous to a cholescintigraphy. The radiopharmaceutical may be localized in the bone marrow. During cardiac acquisition, when the area being viewed includes the lower thorax and abdomen, abnormalities of the liver, gallbladder and kidneys, and the radioactivity in the oesophagus, stomach and bowel, as well as bone marrow uptake, can be depicted by routine raw data cine images. Excluding the intrathoracic abnormalities, these abdominal abnormalities are illustrated in this paper.Retrospectively, we reviewed the raw data cine images from 566 patients. These images were 180 degrees or 360 degrees rotation and showed the abdominal organs and thoracic cage, including the ribs, sternum and spine. We found 234 abnormalities, which were correlated with radiography, laboratory and clinical findings.Intra-abdominal abnormalities included bone marrow visualization, 93 occurrences (39.7%); duodeno-gastric (DG) and entero-gastric (EG) reflux, 47 (20.1%); non-visualization of the gallbladder, including possible causes of cholelithiasis, acute cholecystitis, or cholecystectomy, 31 (13.2%); elevation of the right diaphragm and depression of diaphragm, 30 (12.8%); renal abnormalities, including absent kidney, renal atrophy and cyst, 12 (5.1%); splenomegaly, 10 (4.3%); liver, including hepatomegaly and cirrhosis of the liver, eight (3.4%); and breast attenuation resulting in photopenia in the liver, three (1.2%).(1) The bone marrow uptake of the vertebrae accounts for almost 40% of the abdominal abnormalities, and is usually concordant with anaemia; (2) DG and EG refluxes represent 20% of abdominal abnormalities; they may have a clinical impact and may or may not interfere with SPECT processes and result in artifacts of the inferior wall of the left ventricle; (3) non-visualization of the gallbladder should prompt a search for cholelithiasis; and (4) benign renal cyst or cirrhosis of the liver could also be demonstrated. These coincidental findings may be included in routine cardiac SPECT reports that may have clinical impact because they give the referring physician the chance to pursue further clinical investigation.

OBJECTIVE This study was performed to assess whether post-stress and rest functional parameters, as measured by gated-SPECT, provide additional predictive value for long-term prognosis, over clinical and perfusion data in patients (pts.) with low left ventricular ejection fraction (LVEF). METHODS 647 consecutive pts. underwent stress/rest gated-SPECT, and 497 were followed for a mean period of 516 +/- 264 days. Segmental perfusion and motion/thickening (post-stress and rest) were analysed visually, while EF and LV volumes were calculated using an automatic algorithm (QGS). The post-stress and rest ratio were determined for both end-diastolic (EDV) and end-systolic volume (ESV), while the post-stress LVEF change was calculated subtracting rest-EF from stress-EF. RESULTS 84/497 pts. showed rest EF < 40%, and 15/84 (18%) experienced a cardiac event (3 cardiac deaths, 1 infarction, 3 hospitalized angina and 9 late revascularizations). The perfusion and functional parameters were not significantly more compromised in pts. with cardiac events compared with pts. without events. Post-stress ESV was the only index significantly higher in pts. with low EF and events compared with pts. with low EF without events (150 +/- 72 ml vs. 123 +/- 53 ml, P = 0.02). Univariate Cox analysis of clinical, perfusion and functional data showed that the best predictor of cardiac events was stress-ESV (score 6.5, P = 0.01), followed by rest-ESV, rest-EDV, stress-EDV and stress-LVEF. Multivariate analysis demonstrated that the addition of stress-ESV to stress-EF, yielded a significant increase in the global chi2 in the prediction of hard events (cardiac death/infarction) (score 4.634, P = 0.03). CONCLUSION In patients with depressed LVEF, stress-ESV was the only independent predictor of long-term outcome.

99mTc-tetrofosmin seems to show a prolonged thyroid retention when compared with 99m Tc-sestamibi; this may explain its poorer performance in the dual-phase parathyroid scintigraphy. In order to verify objectively whether and to what extent 99m Tc-sestamibi and 99m Tc-tetrofosmin uptake and retention differ in the thyroid gland, we performed a head-to-head comparison between the tracers in 86 euthyroid subjects enrolled in five centres. Data were compared with those of 99m Tc-pertechnetate obtained from the same subjects. For comparison purposes, quantitative data from the salivary glands were also obtained. 99m Tc-sestamibi showed a higher early thyroid uptake (2.26±0.52 vs. 2.01±0.49, respectively; P

We investigated 99mTc-tetrofosmin scintigraphy in 27 patients with Kaposi’s sarcoma: 20 had classic (CK), 5 AIDS-associated (AK) and 2 transplantation-associated (TK) variants. Twenty-three patients had clinically evident cutaneous and/or mucosal lesions, 9 of them with associated sarcomatous lymphadenopathy; 2 TK patients had only lymph nodes or other extracutaneous Kaposi sites. Both planar and SPECT 99mTc-tetrofosmin scintigraphies were performed in all cases and neck pinhole (P)-SPECT in selected patients. 99mTc-tetrofosmin uptake was observed in 88% of patients with clinically evident cutaneous and/or extracutaneous Kaposi lesions. Scintigraphy gave additional information on cutaneous lesion extent, particularly SPECT regarding deep invasion and subclinical sites in some cases. However, scintigraphy was less sensitive in the detection of small, isolated and scattered lesions. SPECT/P-SPECT were positive in 8/8 patients with sarcomatous lymph nodes, planar imaging in 5/8, ultrasonography in 7/8, while all procedures were negative in 6 other patients with reactive or HIV infection lymph nodes. SPECT demonstrated lymphadenopathy remission in 1 TK patient after immunosuppressive therapy modification and, like planar imaging, ascertained an associated lymphoma with 67Ga-citrate combined. 99mTc-tetrofosmin scintigraphy, especially SPECT, can be useful both in the detection and staging of Kaposi sarcoma lesions as a complementary tool to clinical and other conventional diagnostic methods.

The purpose of this investigation was to compare the efficiency of two different imaging protocols using two different clinically available 99mTc labelled myocardial perfusion tracers. One thousand one hundred and thirty-four imaging studies were performed prospectively, using either 99mTc-tetrofosmin or 99mTc-sestamibi, alternating the use of each tracer for a total period of 8 months. 99mTc-tetrofosmin rest studies were performed with injections of 259MBq-370MBq and imaging 30 min later. Exercise studies were performed with injections of 777MBq-1.11GBq and imaging 20 min later. 99mTc-sestamibi studies used doses similar to those in the 99mTc-tetrofosmin studies. Imaging followed a standard procedure, at 60 min after rest injection, and 30 min after exercise. For patients undergoing pharmacological stress testing99mTc-sestamibi was imaged 45 min after injection and 99mTc-tetrofosmin was imaged 30 min after injection. Variables analysed were (1) injection-to-imaging time for the procedure, and (2) the number of repeated scans because of extra cardiac activity. The completion time for the rest study was significantly shorter for 99mTc-tetrofosmin compared to 99mTc-sestamibi (47.7+/-21.7 min vs 74.3+/-25.8 min P

Myocellular kinetics of 201Tl, 99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-furifosmin were investigated using retrogradely-perfused guinea-pig hearts. Relative retention decreased in the order 99mTc-MIBI ==> 99mTc-tetrofosmin ==> 99mTc-furifosmin. 201Tl and 99mTc-MIBI exhibited bi- (t1,t2), 99mTc-tetrofosmin and 99mTc-furifosmin triexponential (t1,t2,t3) time-activity-curves. Latest-phase elimination-half-life increased from 201Tl (t2) ==> 99mTc-MIBI (t2) ==> 99mTc-tetrofosmin (t3) ==> 99mTc-furifosmin (t3), showing a significant increase in deteriorating myocardium for all tracers but 99mTc-furifosmin. Delayed elimination in deteriorating myocardium explains at least partly the redistribution phenomenon of 201Tl, and suggests a similar phenomenon for 99mTc-MIBI and 99mTc-tetrofosmin.

Resumen —Se ha realizado el estudio mediante SPECT y 99mTc-Tetrofosmin (TTF) en 115 pacientes con 119 lesiones pulmonares sospechosas de malignidad para valorar los posibles factores que intervienen en la captacion del radiofarmaco. Los indices de captacion del tumor respecto al tejido sano (indice TTF) se evaluaron respecto a: benignidad y malignidad, tipo histologico, estadio, diferenciacion celular, tamano, necrosis, supervivencia y la influencia de la P-glicoproteina (Pgp) en la captacion de TTF, detectada mediante inmunohistoquimica. En las 18 lesiones benignas estudiadas la media del indice TTF fue 1,01 ± 0,05 mientras que en las 101 malignas 1,59 ± 0,45 (p 3cm presentaron mayor captacion que los inferiores. En los pacientes con cancer de pulmon de celula no pequena se detecto una relacion positiva entre el indice TTF y la supervivencia, no asi en los pacientes con cancer de pulmon de celula pequena. En los tumores en los que se determino la presencia de Pgp existia una relacion inversa entre los indices de TTF y la expresion de Pgp. En suma, el estudio mediante SPECT toracico y 99mTc-TTF tiene un alto valor predictivo positivo para la presencia de cancer de pulmon, aunque un estudio negativo no excluye su existencia. Esto es debido a que existe una relacion inversa entre la captacion de 99mTc-TTF y la densidad de expresion de la Pgp.

Background Proton-pump inhibitors (PPIs) induce potentially interfering stomach wall activity in single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) with technetium-99m ((99m)Tc)-sestamibi. However, no data are available for (99m)Tc-tetrofosmin. We assessed the influence of prolonged (>2 weeks) PPI use on the stomach wall uptake of (99m)Tc-tetrofosmin in patients referred for stress MPI with a cadmium-zinc-telluride-based SPECT camera and its relation with dyspepsia symptoms. Methods and results Consecutive patients (n=127) underwent a 1-day adenosine stress-first SPECT-MPI with (99m)Tc-tetrofosmin, of whom 54 (43%) patients had been on PPIs for more than 2 weeks. Stomach wall activity was identified on stress SPECT using computed tomographic attenuation maps and was scored using a four-point grading scale into clinically relevant (scores 2 or 3) or nonrelevant (scores 0 or 1).Patients on PPIs had stomach wall uptake more frequently as compared with patients not using PPIs (22 vs. 7%, P=0.017). Dyspepsia was similar in both groups. Conclusion Prolonged use of PPIs is associated with stomach wall uptake of (99m)Tc-tetrofosmin in stress cadmium-zinc-telluride-SPECT images. Gastric symptoms were not associated with stomach wall uptake.

We evaluated the diagnostic accuracy of a new method for quantitative analysis of myocardial perfusion at exercise using 99m Tc-tetrofosmin tomographic imaging. m Tc-tetrofosmin imaging of an exercise-rest sequence was performed in 30 patients with coronary artery disease (CAD) and eight age-matched control subjects. The exercise-induced myocardial count increase was calculated as the relative value (per cent increase ratio, %IR) to that at rest by correcting for physical decay for 99m Tc and injected doses and by a subtraction technique. Exercise and rest 99m Tc-tetrofosmin images were assessed visually and quantitatively using the per cent peak count and %IR of the myocardial count at exercise. Segments with significant coronary stenosis (diameter stenosis =75% or more) showed a significantly lower %IR than did those without significant coronary stenosis in the CAD patients (37 ± 19% vs 63 ± 21%, P < 0.05). The diagnostic efficacy of visual analysis for detecting coronary stenosis was as follows: sensitivity, 58.1% and specificity, 81.4%. When %IR=37% was used for detecting significant coronary stenosis, sensitivity and specificity increased to 74.2% and 93.2%, respectively. Furthermore, the quantitative analysis significantly (P=0.04) improved the overall diagnostic accuracy from 73.3% to 86.7% compared to that of visual assessment. Thus, augmentation of myocardial 99m Tc-tetrofosmin uptake at exercise is blunted in the myocardium with significant coronary stenosis. The calculation of myocardial count increase at exercise relative to that at rest can improve the diagnostic value of 99m Tc-tetrofosmin SPECT imaging and may contribute to more accurate quantification of myocardial ischaemia and impaired tracer uptake in coronary artery disease.

The radioactivity in the organs adjacent to the heart causes interference with the quantitative assessment of myocardial uptake of tracer on scintigraphy. In order to investigate how much the functions of these organs affect myocardial uptake seen in imaging, we compared the myocardial uptake measured by means of a gamma camera with the actual activity in the excised organs.Methods: Thirty-three rats were imaged at 5, 10, 15, 30, 45, 60, 90 and 120 min after the administration of99mTc-tetrofosmin, and % injected dose per pixel (%ID/pixel) for each organ was assessed on planar images (PI measurement). Percent injected dose per gram of tissue (%ID/g) in the heart as well as lungs, liver, gastrointestines and blood was measured by means of a well scintillation counter (WC measurement). Comparison between PI and WC measurements was performed with % uptake, the PI-to-WC ratio and heart-to-organ ratios.Results: Our WC measurement showed an increase in cardiac uptake until 30 min (1.67±0.31%) postinjection and subsequent gradual decrease, whereas PI measurement showed maximum activity of 1.81±0.52% at 15 min postinjection. There was a prominent difference between the two measurements, particularly at 10 min, with a PI/WC ratio of about 1.6 times. Our WC measurement showed maximum pulmonary uptake at 15 min (0.87±0.31%) and a gradual decrease over 15 min, whereas PI measurement showed maximum uptake at 10 min (1.14±0.38%). There was hardly any variation in activity observed later than at 10 min. Our WC measurement showed hardly any variance in hepatic activity from 5 min (0.77±0.19%) to 30 min (0.69±0.27%) with a subsequent gradual decrease. The percent uptake in PI measurement was generally greater than that in WC measurement, and high values were found at 10 min and 15 min with PI/WC ratios of about 3.3 times and 2.3 times, respectively.Conclusion: Percent uptakes in PI measurement were greater than those in WC measurement. The difference between the two measurements was prominent in the early phases. The cardiac uptake in PI measurement was significantly greater than that in WC measurement at 10 min. It was considered that this discrepancy between the two measurements was caused by the Compton scatter from the organs adjacent to the heart.

Objective The quantitative gated SPECT (QGS) software is able to calculate LV volumes and visualize LV wall motion and perfusion throughout the cardiac cycle using an automatic edge detection algorithm of the left ventricle. We evaluated the reliability of global and regional LV function assessment derived from QGS by comparing it with the results from left ventriculo-cineangiography (LVG). Patients In 20 patients with left ventricular dysfunction who underwent ECG gated 99mTc-tetrofosmin SPECT, the end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (LVEF) were calculated. The QGS-assessed regional wall motion was determined using the cinematic display. Results QGS-derived EDV, ESV and LVEF correlated well with those by LVG (p

A 68-year-old man suffering from chronic heart failure due to coronary artery disease (CAD) underwent rest technetium-99m (99mTc)-tetrofosmin and thallium-201 (201Tl) with reinjection studies, but died thereafter. The heart was removed and sectioned into short-axis slices and examined by gross and microscopic pathologic methods. A close correlation between the amount of residual cardiomyocytes and the level of regional tracer activity in the left ventricular wall was obtained for redistribution 201Tl, reinjection 201Tl and rest 99mTc tetrofosmin images. The correlation coefficients were r=0.901 for the 201Tl redistribution images, r=0.913 for the 201Tl reinjection images and r=0.917 for the rest 99mTc-tetrofosmin images. This case report provides further evidence of the validity of SPECT tetrofosmin imaging for the determination of myocardial viability in CAD. (Jpn Circ J 1999; 63: 64 - 67)

We present a patient with a large hiatal hernia resulting in duodenogastric reflux that was seen as abnormal activity below and behind the heart (retrocardiac) on SPECT images and on (99m)Tc-tetrofosmin cardiac SPECT raw-data projection images. Incidental findings such as extra- and retrocardiac activity in the thorax and abdomen should be included on all comprehensive cardiac SPECT reports.

99mTc-tetrofosmin myocardial imaging was performed in a 62-year-old woman who had undergone standard radical mastectomy for right breast cancer 6 years ago. Although the result was negative for the ischemic heart disease, it showed abnormal accumulation corresponding to the bone metastases in the spine. We believe that 99mTc-tetrofosmin imaging is helpful in detecting bone metastases from breast cancer.

Estudiamos de forma preliminar la captacion del nuevo radiofarmaco 99m Tc-tetrofosmin en carcinomas primarios de pulmon. Se analizan los resultados de los 5 casos estudiados de forma preoperatoria con tomografia tipo SPECT pulmonar (segun las siglas internacionales). Los hallazgos de imagen se contrastan con los resultados de la cirugia. El tamano de las tumoraciones oscilaba entre 3,5 y 9 cm. Las imagenes obtenidas, en todos los casos, demuestran una satisfactoria captacion del radiotrazador por la neoplasia que se define claramente del tejido pulmonar normal adyacente sin hallarse signos de interferencia por estructuras contiguas captantes del 99m Tc-tetrofosmin (corazon e higado) gracias a la resolucion espacial de las tomografias. Dados los resultados preliminares de este estudio, podemos afirmar que la SPECT pulmonar, utilizando el 99m Tc-tetrofosmin, puede ser una herramienta util en el diagnostico clinico de las tumoraciones malignas pulmonares, aunque se necesita seguir investigando para valorar el alcance de este hallazgo.

Hypoxia reduces the uptake of technetium-99m sestamibi (MIBI) in human cancer cell lines. In the current investigation, we attempted to identify the relationship between hypoxia-induced alteration of (99m)Tc-MIBI accumulation and expression of multi-drug resistance-associated protein (MRP) in the MCF7/WT breast cancer cell line and its subclonal cell line, MCF7/VP, which expresses high levels of MRP1. A second cationic compound, (99m)Tc-tetrofosmin (TF), was also examined. Cellular uptake of (99m)Tc-MIBI and (99m)Tc-TF was significantly higher in parental MCF7/WT cells than in MCF7/VP cells. Hypoxic conditions generated with a mixture of 95% N(2) and 5% CO(2) reduced cellular uptake of the two tracers in both parental MCF7/WT cells and MRP1-expressing MCF7/VP cells. Cell binding assay with iodine-125-labelled anti-MRP1 antibody demonstrated its specific binding to MCF7/VP cells. Hypoxia did not affect the amount of antibody bound to MCF7/VP cells. These results indicate that hypoxia-induced reduction of tracer uptake in tumour cells is a phenomenon independent of MRP function.

Chemical subjects, a lot of explanation about abstract concepts. Students' difficulties in understanding abstract concepts should be have a solutions. One solution that can be implemented is using games as a medium of learning in the classroom. Because of that, here a game called "Coronary Heart Diseases Diagnosis Game Using 99mTc-Tetrofosmin (SAN)" is developed to solve that problem. In this game students will act as doctors. Character of the doctor and patient behaviour should be designed in such a way as to resemble the real situation, therefore the proper design is necessary and appropriate for addressing the issue. The results of this study show the design of doctor character model, design of patient character model, the design of the doctor characters behaviour when diagnose coronary heart disease, and the design of the patient characters behaviour when diagnosed with coronary heart disease.

This study was done to examine the effect of asiaticoside on MCF-7 cell uptake of 99mTc-tetrofosmin (99mTc-Tfos) and 99mTc-sestamibi (99mTc-MIBI). Methods: The 3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate the effect of a 50% inhibitory concentration of asiaticoside on MCF-7 cell proliferation. MCF-7 cells were treated with 10, 20, 30, 40, and 50 μM asiaticoside for 48 h and then incubated with 59.2 MBq of either 99mTc-Tfos or 99mTc-MIBI tracer for 60 min. The uptake of the tracers was measured with a dose calibrator. Results: The 50% inhibitory concentration of asiaticoside for MCF-7 cells was determined with the MTT assay to be 40 μM. The uptake results were expressed as the mean ± SE radioactivity in MBq/mg of protein, and P values were also calculated (P values of 0.03 indicated significant differences). In the control (no asiaticoside) and at 10, 20, 30, 40, and 50 μM asiaticoside, the mean levels of 99mTc-Tfos uptake were 0.79 (SE, 0.059) (P = 0.14), 0.84 (SE, 0.057) (P = 0.60), 0.47 (SE, 0.034) (P = 0.03), 0.40 (SE, 0.050) (P = 0.03), 0.37 (SE, 0.050) (P = 0.03), and 0.15 (SE, 0.023) (P = 0.03), respectively; the mean levels of 99mTc-MIBI uptake were 0.95 (SE, 0.007) (P = 0.14), 0.81 (SE, 0.009) (P = 0.60), 0.79 (SE, 0.019) (P = 0.03), 0.63 (SE, 0.004) (P = 0.03), 0.13 (SE, 0.006) (P = 0.03), and 0.07 (SE, 0.008) (P = 0.03), respectively. Asiaticoside concentrations of 10, 20, 30, 40, and 50 μM revealed the uptake kinetics for both 99mTc-Tfos and 99mTc-MIBI in MCF-7 cells. 99mTc-Tfos and 99mTc-MIBI showed similar trends; the radioactivity uptake was dose dependent, and asiaticoside inhibited 16% and 47% of 99mTc-Tfos uptake and 99mTc-MIBI uptake in MCF-7 cells, respectively. Conclusion: This study showed that asiaticoside, acting as a biochemical modulator, may induce apoptosis and enhance antitumor activity in MCF-7 cells, as determined by 99mTc-Tfos and 99mTc-MIBI uptake. These findings are promising for cancer chemotherapy. Future studies should be performed to confirm our findings and to further delineate the clinical role of asiaticoside.