The utility and prognostic value of dipyridamole technetium-99m sestamibi myocardial perfusion imaging SPECT in predicting perioperative cardiac events following non-cardiac surgery

Objective: A perioperative cardiac events is one of the most important medical concerns for both surgeons and patients. The purpose of the current study was to determine the prognostic value of myocardial perfusion imaging (MPI), using dipyridamole 99m Tc-MIBI, for the prediction of perioperative cardiac events. Materials and methods: This study included 253 patients who were candidates for non-cardiac elective surgery and underwent scanning with dipyridamole 99m Tc-MIBI. Based on normal or abnormal MPI, patients were divided into two groups and all preoperative cardiac events were recorded. Risk factors, including diabetes mellitus, dyslipidemia, hypertension, smoking and age .70 years, were compared between patients with normal and abnormal MPI and, also, in patients with or without cardiac events. Results: There were 197 patients with normal and 56 patients with abnormal MPI. In total, 14 patients had perioperative cardiac events, which included myocardial infarction (MI), hypotension, arrhythmia and death; of the 14 patients with perioperative cardiac events, 12 had abnormal and two had normal MPI. There were statistically meaningful differences between the two groups (p<0.001). Based on these findings, we determined that MPI had a sensitivity of 85.7%, a specificity of 81.6%, an accuracy of 81.8%, a positive predictive value of 21.4 % and a negative predictive value of 98.9%. Conclusion: The incidence of perioperative cardiac events is higher in patients with abnormal MPI. Dipyridamole 99m Tc-MIBI myocardial perfusion imaging can accurately detect the preoperative cardiac risk of patients undergoing major non-cardiac surgery. Based on these findings, the occurrence of perioperative cardiac events in patients with abnormal MPI should be considered, especially in the older age population (age ≥70). © The Author(s) 2013

A study of the time of hospital discharge of differentiated thyroid cancer patients after receiving iodine-131 for thyroid remnant ablation treatment

The aim of this study was to measure the radiation exposure rate from differentiated thyroid carcinoma (DTC) patients who had received iodine-131 (131I) treatment, and to evaluate hospital discharge planning in relation to three different sets of regulations. We studied 100 patients, 78 females and 22 males, aged 13 to 79 years (mean 44.40±15.83 years) with DTC, in three Groups who were treated with 3.7, 5.5 or 7.4GBq of 131I, respectively. The external whole-body dose rates following oral administration of 131I were measured after each one of the first three hospitalization days. A multivariant linear analysis was performed, considering exposure rates as dependent variables to the administered dose for treatment, age, gender, regional and/or distant metastases, thyroglobulin (Tg), antibodies to Tg and thyroid remnant in the three dose groups. We found that the exposure rates after each of the three first days of hospitalization were 30, 50 and 70μSvh-1 at 1m. All our DTC patients had an acceptable dose rate on days 2 and 3 that allowed their hospital discharge. After only 1 day of hospitalization, just 3/11 cases showed not permissible exposure rates above 70μSvh-1. In conclusion, it is the opinion of the authors that after measuring the exposure rates, most treated, DTC patients could be discharged after only one day of hospitalization, even some of those treated with high doses of 131I (7.4GBq). Patients, who received the higher doses of 131I, should not be released before their individual exposure rate is measured

Hepatopulmonary syndrome with right-to-left shunt in cirrhotic patients using macro-aggregated albumin lung perfusion scan: Comparison with contrast echocardiography and association with clinical data [Sirotik hastalardaki sağ-sol şant ile ilişkili hepatopulmoner sendromun tanısında makro-agregant albümin akciğer perfüzyon sintigrafisinin kontrast ekokardiyografi ile karşılaştırılması ve klinik veriler ile ilişkisi]

Objectives: The diagnosis of hepatopulmonary syndrome (HPS) which is a common complication in cirrhotic patients is still subject to debate. This study investigated the association of clinical findings with HPS in cirrhotic patients using macro-aggregated albumin lung perfusion scan (99mTc-MAA lung scintigraphy). In addition, comparison between99mTc-MAA lung scintigraphy and contrast echocardiography (CEE) in detection of HPS was also performed. Methods: In this study, 27 patients with cirrhosis underwent99mTc-MAA lung scintigraphy and contrast echocardiography comparison CEE and the frequency of HPS was assessed in them and also was compared across the other variables. Results: The99mTc-MAA lung scintigraphy showed HPS in 13 patients (48.1%) while CEE demonstrated HPS in 5 patients with cirrhosis (18.51%). HPS was mild in 40.74% (11/27) of the patients, and severe in only 2 patients. There was no relationship between gender, disease duration, having diagnosis of disease previously, pulmonary symptoms and Child-Pugh score variations and HPS (p>0.05). Comparison of hemodynamic indices, arterial blood gas analysis and laboratory indices between patients with and without HPS was also non-significant (p value >0.05). Among coagulation factors assessed in cirrhotic patients, we found only significant correlation between HPS and prothrombin time (p<0.05). Conclusion: HPS, particularly its mild form, is noted in a great number of patients with cirrhosis using 99mTc-MAA lung scintigraphy. Because of its technical ease, and possibility to obtain objective quantitative information,99mTc-MAA lung scintigraphy can be complementary to other diagnostic methods in the evaluation of HPS assessment, although additional studies are needed

Significance of microalbuminuria in predicting silent myocardial ischemia in patients with type 2 diabetes using myocardial perfusion imaging

Objectives: In light of increased risk of cardiovascular events and the poor prognosis of coronary artery disease (CAD) in diabetic versus non-diabetic patients and also with respect to the importance of early diagnosis of CAD in this status, the study was aimed to assess the importance of microalbuminuria in predicting silent myocardial ischemia (SMI) in patients with type 2 diabetes using myocardial perfusion imaging (MPI). Methods: This study included 120 patients with diabetes type 2, but without previously known CAD or any cardiac symptoms that were stratified into two groups based on presence/absence of microalbuminuria. All participants underwent CAD evaluation using gated myocardial perfusion single-photon emission computed tomography (MPS) imaging. Other clinical and laboratory indices were also recorded. Results: Studied population consisted of 84 males (70%) and 36 females (30%), totally 120 patients with mean age of 58.61±9.90). In total, asymptomatic ischemia was detected in 78 (65%) of the included diabetic patients. Stress induced ischemia was found in 56 patients (87.5%) of albumin+ (Alb) group and in 22 patients (39.3%) of Alb-group. The frequency of stress induced ischemia was 10.81 times higher in the patients with microalbuminuria compared to Alb-ones [p0.05). Conclusion: The current study showed that abnormal MPI findings are significantly more common in diabetic patients with microalbuminuria. With respect to low cost and availability of urine Alb detection tests, it might be as a biomarker for prediction of SMI in diabetic population. © 2019 by Turkish Society of Nuclear Medicine Molecular Imaging and Radionuclide Therapy published by Galenos Yayınevi

Assessment of radioiodine clearance in patients with differentiated thyroid cancer

Radioiodine (131I iodide) has long been a safe, effective and widely used treatment in the management of differentiated thyroid cancer (DTC). Concerns regarding stochastic radiogenic risks have led to regulatory criteria for the release from medical confinement of patients who receive such radionuclide therapy. Over a 6-y period, the external whole-body dose rates at 1 m from 562 DTC patients were measured with an ionisation chamber calibrated in microsieverts per hour out to 5-d post-administration. Patients were stratified into four administered activity groups: 3.7 GBq (36.8 ), 5.55 GBq (47.3 ), 7.4 GBq (12.8 ) and 9.25 GBq (3 ). Consistent with previously published data, the current study demonstrated that a bi-phasic model accurately described 131I-iodide kinetics up to at least 5-d post-administration in DTC patients, providing data that would be useful in formulating radiation safety guidelines for staff and other individuals coming into contact with such patients after treatment. © The Author 2012. Published by Oxford University Press. All rights reserved

Role of 99mTc-ubiquicidin 29-41 scintigraphy to monitor antibiotic therapy in patients with orthopedic infection: A preliminary study

Introduction: Ubiquicidin (UBI) 29-41 is a cationic synthetic antimicrobial peptide fragment that binds preferentially with anionic microbial cell membranes at the site of infection. This study evaluated the potential ability of Tc-UBI 29-41 to assess response to antibiotic therapy in orthopedic infection. Methods: A total of 12 patients, 10 men and two women (mean age, 41.6 years; range, 23-75 years), with suspected orthopedic infection (bone, soft tissue, or prosthesis) and positive Tc-UBI scan for infection were included in the study. One day after the Tc-UBI scan, a bone scan was performed as well. After this evaluation, eight of the nine treated cases responded to the treatment. Then, one nonresponder patient and two nontreated patients of three cases underwent antibiotic therapy and were evaluated again 10-14 days later. After this, one of the two patients not treated the first time responded to therapy and two patients did not. Moreover, one patient refused to undergo therapy both the first and second time. Thus, 11 treated cases were analyzed in this study and divided in two groups: (a) nine treated responders and (b) two treated nonresponders. In all patients, erythrocyte sedimentation rate and C-reactive protein were measured and also wound cultures were assessed. Results: Quantitative analysis of erythrocyte sedimentation rate, C-reactive protein, and bone scan before and after the 10-14-day interval showed no significant change in either group, but a quantitative Tc-UBI scan at 30, 60, and 120 min after tracer injection indicated significant reduction in radiotracer uptake after the 10-14-day interval compared with the Tc-UBI scan before this interval in the responder group, and no significant change in the nonresponder group. Conclusion: The Tc-UBI scan can determine response to antibiotic therapy in orthopedic infection in humans. © 2011 Wolters Kluwer Health | Lippincott Williams and Wilkins

A novel scintigraphic agent, 99m Tc -UBI 29-41, to monitor antibiotic therapy in patients with orthopedic infection

Aim: Ubiquicidin (UBI) 29-41 is a cationic synthetic antimicrobial peptide fragment that binds preferentially with anionic microbial cell membranes at the site of infection. The current study evaluated the potential ability of 99m Tc-UBI 29-41 to assess response to antibiotic therapy in orthopedic infection.Matherials and methods: A total of 12 patients, 10 male and 2 female (mean age 41.6y; range 23- 75y), with suspected orthopedic infection (bone, soft tissue, or prosthesis) and positive UBI scan for infection were included in the study. One day after the 99m Tc-UBI scan, a bone scan was performed as well. After the first scan series, 9 of the 12 patients underwent appropriate treatment including empirical antibiotics; 3 patients refused treatment. After a 10-14 day interval all patients were divided into two groups: a) responder to therapy and 2) non-responder/non-treated. In all 12 patients, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured; and in most of them, wound cultures were carried out before and after the 10-14 day interval. Then, 3 of the 4 patients in the non-responder/non-treated group underwent antibiotic therapy and were evaluated again after 10-14 days. One of these patients responded to recent therapy and 2 patients did not. Thus, 15 cases were analyzed in this study and divided in two groups: a) 9 responder and b) 6 non-responder/non-treated. Results: Quantitative analysis of ESR, CRP, and bone scan before and after the 10-14 day interval showed no significant change in either group, but a quantitative 99m Tc-UBI scan 30, 60, and 120 minutes after tracer injection indicated significant reduction in radiotracer uptake after the 10-14 day interval compared to the 99m Tc-UBI scan before this interval in the responder group, and no significant change in the non-responder/ non -treated group. Conclusion: The 99m Tc-UBI scan can determine response to antibiotic therapy in orthopedic infection in humans

The role of cognitive group therapy and happiness training on cerebral blood flow using 99mTc-ECD brain perfusion SPECT: A quasi-experimental study of depressed patients

Abstract Objective: The purpose of this study is to investigate the impact of cognitive group therapy and happiness training objectively in the local cerebral blood flow of patients with major depression (MD). Patients, material, methods: The present research is semi-experimental to pre- and post-test with a control group. Three groups were formed, and this number was incorporated in each group: 12 patients were chosen randomly; the first group of depressed patients benefited from the combination of pharmacotherapy and sessions of cognitive group therapy; the second group used a combination of pharmaco-therapy and sessions of happiness training; and a third group used only pharmacother-apy. We compared cognitive-behavioural therapy and happiness training efficacy with only pharmacotherapy in MD patients. We performed brain perfusion SPECT in each group, before and after each trial. Results: The study was conducted on 36 patients with MD (32 women and 4 men; mean age: 41.22 ± 9.08; range: 27–65 years). There were significant differences regarding the two trial effects into two experimental groups (p 0.05). In addition, there was significant difference among the regional cerebral blood flow in the frontal and prefrontal regions into two experimental groups before and after trials (p 0.05). Conclusion: This study demonstrated decreased cerebral perfusion in the frontal regions in MD patients, which increased following cognitive group therapy and happiness training. Because of its availability, low costs, easy performance, and the objective semi-quantitative information supplied, brain perfusion SPECT scanning might be useful to assess the diagnosis and therapy efficacy. Further exploration is needed to validate its clinical role. © Schattauer 2014

Factors That Impact Evaluation of Left Ventricular Systolic Parameters in Myocardial Perfusion Gated SPECT with 16 Frame and 8 Frame Acquisition Models

OBJECTIVE: Evaluating the effects of heart cavity volume, presence and absence of perfusion defect, gender and type of study (stress and rest) on the difference of systolic parameters of myocardial perfusion scan in 16 and 8 framing gated SPECT imaging. METHODS: Cardiac gated SPECT in both 16 and 8 framing simultaneously and both stress and rest phases at one-day protocol was performed for 50 patients. Data have been reconstructed by filter back projection (FBP) method and left ventricular (LV) systolic parameters were calculated by using QGS software. The effect of some factors such as LV cavity volume, presence and absence of perfusion defect, gender and type of study on data difference between 8 and 16 frames were evaluated. RESULTS: The differences in ejection fraction (EF), end-diastolic volume (EDV) and end-systolic volume (ESV) in both stress and rest were statistically significant. Difference in both framing was more in stress for EF and ESV, and was more in rest for EDV. Study type had a significant effect on differences in systolic parameters while gender had a significant effect on differences in EF and ESV in rest between both framings. CONCLUSION: In conclusion, results of this study revealed that difference of both 16 and 8 frames data in systolic phase were statistically significant and it seems that because of better efficiency of 16 frames, it cannot be replaced by 8 frames. Further well-designed studies are required to verify these findings

The electromagnetic interference of mobile phones on the function of a γ-camera

PURPOSE: The aim of the present study is to evaluate whether or not the electromagnetic field generated by mobile phones interferes with the function of a SPECT γ-camera during data acquisition. METHODS: We tested the effects of 7 models of mobile phones on 1 SPECT γ-camera. The mobile phones were tested when making a call, in ringing mode, and in standby mode. The γ-camera function was assessed during data acquisition from a planar source and a point source of Tc with activities of 10 mCi and 3 mCi, respectively. A significant visual decrease in count number was considered to be electromagnetic interference (EMI). RESULTS: The percentage of induced EMI with the γ-camera per mobile phone was in the range of 0% to 100%. The incidence of EMI was mainly observed in the first seconds of ringing and then mitigated in the following frames. CONCLUSIONS: Mobile phones are portable sources of electromagnetic radiation, and there is interference potential with the function of SPECT γ-cameras leading to adverse effects on the quality of the acquired images. © 2013 by Lippincott Williams and Wilkins