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1.
J Supercomput ; : 1-51, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37359340

RESUMO

This paper proposes a novel approach that uses a spectral clustering method to cluster patients with e-health IoT devices based on their similarity and distance and connect each cluster to an SDN edge node for efficient caching. The proposed MFO-Edge Caching algorithm is considered for selecting the near-optimal data options for caching based on considered criteria and improving QoS. Experimental results demonstrate that the proposed approach outperforms other methods in terms of performance, achieving decrease in average time between data retrieval delays and the cache hit rate of 76%. Emergency and on-demand requests are prioritized for caching response packets, while periodic requests have a lower cache hit ratio of 35%. The approach shows improvement in performance compared to other methods, highlighting the effectiveness of SDN-Edge caching and clustering for optimizing e-health network resources.

2.
Pers Ubiquitous Comput ; 27(3): 697-713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-33223984

RESUMO

Internet of Things (IoT) and smart medical devices have improved the healthcare systems by enabling remote monitoring and screening of the patients' health conditions anywhere and anytime. Due to an unexpected and huge increasing in number of patients during coronavirus (novel COVID-19) pandemic, it is considerably indispensable to monitor patients' health condition continuously before any serious disorder or infection occur. According to transferring the huge volume of produced sensitive health data of patients who do not want their private medical information to be revealed, dealing with security issues of IoT data as a major concern and a challenging problem has remained yet. Encountering this challenge, in this paper, a remote health monitoring model that applies a lightweight block encryption method for provisioning security for health and medical data in cloud-based IoT environment is presented. In this model, the patients' health statuses are determined via predicting critical situations through data mining methods for analyzing their biological data sensed by smart medical IoT devices in which a lightweight secure block encryption technique is used to ensure the patients' sensitive data become protected. Lightweight block encryption methods have a crucial effective influence on this sort of systems due to the restricted resources in IoT platforms. Experimental outcomes show that K-star classification method achieves the best results among RF, MLP, SVM, and J48 classifiers, with accuracy of 95%, precision of 94.5%, recall of 93.5%, and f-score of 93.99%. Therefore, regarding the attained outcomes, the suggested model is successful in achieving an effective remote health monitoring model assisted by secure IoT data in cloud-based IoT platforms.

3.
Addict Health ; 14(3): 224-228, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36544982

RESUMO

Background: Coronary slow flow phenomenon (CSFP) represents a clinical entity with recurrent chest pain leading to living impairment. The present study aimed to investigate whether opium use correlates with primary CSFP. Methods: This study included Iranian patients with suspected coronary artery disease who underwent myocardial perfusion imaging. Coronary blood flow was measured quantitatively using the thrombolysis in myocardial infarction (TIMI) frame count and slow flow was defined as TIMI grade 2 standard deviations. Age and clinical conditions including diabetes mellitus (DM), hypertension (HTN), hyperlipidemia (HLP), history of chest pain, and opium use were recorded. First, the characteristics of the two groups were compared and then the main analyses were conducted to examine the relationship between CSFP and opium use. Data were analyzed using t test and chi-square test via SPSS 25.0. The significance level was set at P<0.05. Findings: This study was conducted on 44 male patients with documented CSFP who had no stenotic lesions and 134 control group male patients who had normal coronary arteries with normal flow. The mean age was similar in the two groups (54.25 vs.52.69, P=0.474). Two groups were significantly different in terms of history of chest pain (P=0.003), but there was no significant difference in HTN (P=0.084), DM (P=0.284), HLP (P=0.183), smoking (P=0.696), and opium use (P=0.107). Conclusion: This study indicated that opium use is not associated with primary CSFP.

4.
Sci Rep ; 12(1): 17520, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266467

RESUMO

SiRNA is a new generation of drug molecules and a new approach for treating a variety of diseases such as cancer and viral infections. SiRNA delivery to cells and translocation into cytoplasm are the main challenges in the clinical application of siRNA. Lipid carriers are one of the most successful carriers for siRNA delivery. In this study, we investigated the interaction of siRNA with a zwitterionic bilayer and how ion concentration and lipid conjugation can affect it. The divalent cation such as Mg2+ ions could promote the siRNA adsorption on the bilayer surface. The cation ions can bind to the head groups of lipids and the grooves of siRNA molecules and form bridges between the siRNA and bilayer surface. Our findings demonstrated the bridges formed by divalent ions could facilitate the attachment of siRNA to the membrane surface. We showed that the divalent cations can regulate the bridging-driven membrane attachment and it seems the result of this modulation can be used for designing biomimetic devices. In the following, we examined the effect of cations on the interaction between siRNA modified by cholesterol and the membrane surface. Our MD simulations showed that in the presence of Mg2+, the electrostatic and vdW energy between the membrane and siRNA were higher compared to those in the presence of NA+. We showed that the electrostatic interaction between membrane and siRNA cannot be facilitated only by cholesterol conjugated. Indeed, cations are essential to create coulomb repulsion and enable membrane attachment. This study provides important insight into liposome carriers for siRNA delivery and could help us in the development of siRNA-based therapeutics. Due to the coronavirus pandemic outbreak, these results may shed light on the new approach for treating these diseases and their molecular details.


Assuntos
Bicamadas Lipídicas , Simulação de Dinâmica Molecular , RNA Interferente Pequeno/genética , Bicamadas Lipídicas/metabolismo , Lipossomos , Cátions Bivalentes , Membrana Celular/metabolismo , Cátions , Colesterol
5.
Artigo em Inglês | MEDLINE | ID: mdl-34746376

RESUMO

Ridge-like regularization often leads to improved generalization performance of machine learning models by mitigating overfitting. While ridge-regularized machine learning methods are widely used in many important applications, direct training via optimization could become challenging in huge data scenarios with millions of examples and features. We tackle such challenges by proposing a general approach that achieves ridge-like regularization through implicit techniques named Minipatch Ridge (MPRidge). Our approach is based on taking an ensemble of coefficients of unregularized learners trained on many tiny, random subsamples of both the examples and features of the training data, which we call minipatches. We empirically demonstrate that MPRidge induces an implicit ridge-like regularizing effect and performs nearly the same as explicit ridge regularization for a general class of predictors including logistic regression, SVM, and robust regression. Embarrassingly parallelizable, MPRidge provides a computationally appealing alternative to inducing ridge-like regularization for improving generalization performance in challenging big-data settings.

6.
World J Nucl Med ; 20(1): 17-22, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33850485

RESUMO

Radioiodine ablation following surgery is the accepted treatment for patients with differentiated thyroid cancer (DTC). Since that surgical volume and radioiodine dose can have impact on treatment outcome, we aimed to evaluate them on the treatment outcome of low-risk DTC patients. Low-risk DTC patients were classified into four groups, including (1) thyroidectomy was performed by thyroid surgeon and low-dose (1850 MBq [30 mCi]) radioiodine was administered (n = 17), (2) thyroidectomy was performed by thyroid surgeon and high-dose (3700 MBq [100 mCi]) radioiodine was administered (n = 10), (3) thyroidectomy was performed by general surgeon and low-dose radioiodine was administered (n = 22), and (4) thyroidectomy was performed by general surgeon and high-dose radioiodine was administered (n = 29). All patients were followed at least for 6 months and also for evaluation of treatment success, neck sonography, thyroid-stimulating hormone-off, thyroglobulin (Tg)-off, and anti-Tg-off tests were performed. Furthermore, two common radioiodine treatment-associated side effects, including dry mouth, and nausea/vomiting were assessed for all patients. Seventy-eight low-risk DTC patients (female: 70 [89.7%]; male: 8 [10.3%]) aged from 18 to 78 years old with mean of 41.96 ± 13.42 years were enrolled in this study. In total, the treatment was successful in 96.2% of patients. There was no significant difference in treatment success among groups (P > 0.05), while there was a significant association among administered activity and side effects. In low dose patients, only one patient complained from dry mouth; however, 11/39 patients who received high dose of iodine complained from dry mouth (P = 0.002). In addition, 9/39 high dose patients suffered from vomiting/nausea, while none of low-dose patients suffered from vomiting/nausea (P = 0.001). In low-risk DTC patients, surgical volume and amounts of radioiodine had no significant impact on treatment results; therefore, low dose radioiodine following thyroidectomy may be preferable to low-risk DTC patients to avoid side effects.

7.
Indian J Crit Care Med ; 25(1): 43-47, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33603300

RESUMO

BACKGROUND: Toxicity and side effects of long-term use of opioids are well studied, but little information exists regarding electrophysiological disturbances of opium consumption. While natural opium has been regarded safe to a great extent among traditional communities, concerns are emerging owing to the available evidence of QT prolongation that have been exposed during recent outcome surveillance of patients under opioid use. Potential QT prolonging interactions would raise a higher level of such concern in opium users during COVID pandemic and warrant attention. MATERIALS AND METHODS: This study was designed to detect the prevalence of QTc prolongation among opium users and nonusers. Two groups were compared with regard to gender, age, and median QTc interval. Normal and prolonged QTc intervals of user group were compared with respect to age, sex, dose of opium consumption, and duration of opium consumption. RESULTS: 123 opium users and 39 controls were investigated. Median QTc interval in opium user and non-user group was 460 vs 386 milliseconds, respectively (p value < 0.001). In all, 59.3%, (95% CI: 50.51-67.62%) of cases and none of non-user had prolonged QTc interval (p value < 0.001). There was no significance between normal and prolonged QTc intervals with respect to dose and duration of opium use. CONCLUSION: This study indicated that opium consumption is associated with QTc prolongation. This prolongation does not relate to dose and duration of opium use. Further study is propounded to assess the clinical significance of these results and to determine risk rating of opium compared to other opioids in this regard. HOW TO CITE THIS ARTICLE: Javadi HR, Mirakbari SM, Allami A, Yazdi Z, Katebi K. Opium-associated QT Interval Prolongation: A Cross-sectional Comparative Study. Indian J Crit Care Med 2021;25(1):43-47.

8.
Nuklearmedizin ; 58(3): 249-257, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31060081

RESUMO

INTRODUCTION: This study aimed to assess the usefulness of a risk-adopted management system known as dynamic risk stratification (DRS) in comparison with the American (ATA) and European Thyroid Associations' (ETA) risk classifications in the management of pediatric patients with differentiated thyroid cancer (DTC). MATERIALS AND METHODS: The current study included 50 pediatric patients with DTC who were treated with total or near total thyroidectomy and radioiodine ablation whose risk assessment was initially defined according to the ATA and ETA guidelines. During the two years after initial treatment, patients were reclassified according to their DRS. RESULTS: The study showed that the ability of the DRS system to predict the final outcome was superior to that of the ATA and ETA guidelines. The observed variance in predicting final outcome was 2.3 % for ETA, 14.8 % for ATA, and 83.4 % for DRS. In intermediate/high-risk patients, according to the ATA/ETA guidelines, an excellent response to initial therapy resulted in a noteworthy reduction (about 40 %) for detection of structural disease at the time of final follow-up. The risk of structural disease at the time of final follow-up was significantly higher in the structural incomplete response group (HR = 23.34, P = 0.00) and biochemical incomplete response group (HR = 13.83, P = 0.03) than in the excellent response group. CONCLUSION: The data documented the significance of re-stratifying pediatric patients with DTC on the basis of the findings obtained at the time of or after their initial therapy (total thyroidectomy and radioiodine ablation), predominantly in the intermediate/high-risk patients. In addition, DRS helped to better modulate the later follow-up, excluding a large number of intermediate/high risk patients from needless intensive workups, allowing personalization of follow-up management.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/terapia , Adolescente , Criança , Pré-Escolar , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Medicina de Precisão , Prognóstico , Estudos Retrospectivos , Medição de Risco , Taxa de Sobrevida , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia , Resultado do Tratamento
9.
Genomics ; 111(6): 1902-1912, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30611877

RESUMO

The ultimate goal of the Recommender System (RS) is to offer a proposal that is very close to the user's real opinion. Data clustering can be effective in increasing the accuracy of production proposals by the RS. In this paper, single-objective hybrid evolutionary approach is proposed for clustering items in the offline collaborative filtering RS. This method, after generating a population of randomized solutions, at each iteration, improves the population of solutions first by Genetic Algorithm (GA) and then by using the Gravitational Emulation Local Search (GELS) algorithm. Simulation results on standard datasets indicate that although the proposed hybrid meta-heuristic algorithm requires a relatively high run time, it can lead to more appropriate clustering of existing data and thus improvement of the Mean Absolute Error (MAE), Root Mean Square Error (RMSE) and Coverage criteria.


Assuntos
Algoritmos , Cromossomos , Análise por Conglomerados , Bases de Dados Factuais , Genética Populacional/métodos , Humanos , Mutação
10.
Materials (Basel) ; 11(12)2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30501094

RESUMO

In current research, the effect of the multi-directional forging (MDF) process on the microstructure, texture, mechanical and electrical properties of AA-6063 under different heat treatment conditions at various MDF temperatures was studied. The annealed AA-6063 alloy was processed up to three passes of MDF at ambient temperature. Three passes of this process were also applied to the solution-treated AA-6063 at ambient temperature and 177 °C. Microstructural investigations demonstrated that the MDF process led to a significant reduction in the average grain size as well as a considerable increase in the fraction of low angle grain boundaries. Texture analysis revealed that copper and Goss textures were mainly developed within the annealed and solution-treated samples of AA-6063, respectively. The hardness and shear strength values of all processed samples also showed a sizeable improvement compared to the initial heat-treated samples. For example, the hardness and shear yield strength value of the solution-treated sample MDFed for three passes showed more than 100 and 70% increase, respectively. The effect of the MDF process on the electrical conductivity of AA-6063 under different heat treatment conditions at various temperatures was negligible. So, it can be concluded that the MDF process increased the mechanical properties without an appreciable decrease in electrical conductivity.

11.
Mol Imaging Radionucl Ther ; 27(2): 55-60, 2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29889026

RESUMO

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.

12.
Mater Sci Eng C Mater Biol Appl ; 78: 1195-1202, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575957

RESUMO

In the present study, for the first time, polycaprolactone (PCL) and gelatin (GEL) were used for neural differentiation of human induced pluripotent stem cells (hiPSCs) in the form of bi-electrospun nanofibers. The electrospun fibers were evaluated by FTIR and tensile analysis. MTT assay was used to evaluate the toxicity on the scaffolds. The hiPSCs were seeded on the fibers and after 14days in neural differentiation medium. To confirm the differentiation, real-time PCR and immunocytochemistry (ICC) analyses were performed. For morphological studies of fibers and cultured cells on them, scanning electron microscopy (SEM) and optical microscopy (OM) were used. Our results indicated that hiPSCs had differentiated to neural cells completely after incubation time. Our study demonstrates that PCL/GEL bi-electrospun nanofibers not only have the capability to support hiPSCs differentiation to neural cells, but they also are able to enhance and improve such process. Overall, PCL/GEL scaffolds seem to be a feasible, reliable and easily accessed composite for further tissue engineering experiments.


Assuntos
Células-Tronco Pluripotentes Induzidas , Diferenciação Celular , Gelatina , Humanos , Nanofibras , Neurônios , Poliésteres , Engenharia Tecidual , Alicerces Teciduais
13.
Mol Imaging Radionucl Ther ; 26(1): 17-23, 2017 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-28291006

RESUMO

OBJECTIVE: Gastroparesis is defined as delayed gastric emptying and is a common medical condition in diabetic patients. Scintigraphy is commonly used as a standard diagnostic procedure for the quantitative assessment of gastroparesis. The aims of this study were to determine an optimum imaging time for the diagnosis of gastroparesis, to assess the prevalence of gastroparesis, to evaluate the correlation between endoscopy and scintigraphy findings as well as the correlation between gastric emptying with patient genders, blood glucose concentration, and functional dyspepsia. METHODS: Gastric emptying was assessed in 50 diabetic patients with a mean age of 50.16 years. For evaluation of gastric emptying, a test meal containing 2 pieces of toast, 120 cc non-labeled water and fried egg labeled with 1 mCi of 99mTc was given to each patient. The scintigraphy was performed immediately after ingestion and was repeated at 1, 1.5, 2 and 4 hours after ingestion. In some patients, an additional 90-minute dynamic scan was also acquired. RESULTS: The prevalence of gastroparesis in this study population was determined as 64%. Also, the results of this study revealed that a 4-hour scan after ingestion is more relevant than a 90-minute dynamic scan for the evaluation of delayed gastric emptying. There was no statistically significant difference between 1-hour and 2-hour scans, 1-hour and 90-minute scans, 2-hour and 90-minute scans, 2-hour and 4-hour scans. Likewise there was no significant correlation between blood glucose levels, gender and calculated values of gastric emptying time in all groups. CONCLUSION: According to our findings, it can be suggested that the prevalence of gastroparesis is higher than that mentioned in some previous studies. Also, this study indicates that a gastric emptying scintigraphy at 2 and 4 hours after meal ingestion might provide the anticipated clinical information in diabetic patients with dyspepsia without other evident reasons.

14.
Clin Nucl Med ; 41(12): 917-921, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27764045

RESUMO

BACKGROUND: Because one of the major sites for metastasis of thyroid cancers is the lung, studying the pattern of pulmonary metastasis may provide useful information for the effective treatment of these patients. In this study, by assessing the metastasis pattern, we aimed to identify the factors that may affect prognosis and response to treatment in patients with differentiated thyroid carcinoma (DTC) with pulmonary metastasis. METHODS: This retrospective study included 75 patients with DTC with pulmonary metastasis who were referred to our nuclear medicine section over a period of 10 years. The data obtained were analyzed with regard to response to treatment to assess the effects of the included factors on prognosis. RESULTS: Of the 1746 patients referred to our section, 75 (4.3%) had pulmonary metastasis. According to the pattern of pulmonary metastasis, they were divided into 4 groups: nodular, diffuse, combined, and other. The mean age of the patients was 43.8 ± 18.5 years. After the follow-up, 58 patients survived, 14 of whom responded to the treatment. The mean number of radioiodine therapy sessions that the patients received was 3.2 ± 2, and the mean cumulative dose was 554.7 ± 387.8 mCi. Statistical analysis of the data revealed that there was no significant difference in the response to treatment between patients with different patterns of pulmonary metastasis (P > 0.3). However, significant differences were reported in the response to treatment between patients with papillary thyroid carcinoma and those with follicular thyroid carcinoma (P < 0.03). The 1-, 5-, and 9-year survival rates were reported as 98%, 76%, and 51%, respectively. CONCLUSIONS: Patients with DTC with pulmonary metastasis have a relatively favorable prognosis and response rate, as well as longer survival. The type of DTC is the only factor that affects the response to treatment.


Assuntos
Adenocarcinoma Folicular/patologia , Carcinoma/patologia , Neoplasias Pulmonares , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Carcinoma Papilar , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Resultado do Tratamento , Adulto Jovem
15.
Nucl Med Rev Cent East Eur ; 19(B): 3-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27813619

RESUMO

Ganglioneuroma (GN) is a rare benign neural tumor, usually derived from the ganglia of the sympathetic system. This report describes a 36-year-old man who presented with back pain and local tenderness that closely mimicked the clinical and ima-ging findings of spondylodiskitis. However, histologic examination made the diagnosis of GN. To our knowledge, this is the first report presenting the pattern of a GN as a differential diagnosis of spondylodiskitis.


Assuntos
Discite/diagnóstico , Ganglioneuroma/diagnóstico , Neoplasias da Medula Espinal/diagnóstico , Adulto , Diagnóstico Diferencial , Discite/diagnóstico por imagem , Ganglioneuroma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Compostos Radiofarmacêuticos , Neoplasias da Medula Espinal/diagnóstico por imagem , Medronato de Tecnécio Tc 99m , Vértebras Torácicas , Imagem Corporal Total
16.
J Clin Diagn Res ; 10(8): TC24-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27656528

RESUMO

INTRODUCTION: Dipyridamole inhibits adenosine reuptake and increases cyclic Adenosine Monophosphate (cAMP) levels in platelets, erythrocytes and endothelial cells, all of which influence blood glucose. Acute hyperglycaemia reduces endothelium-dependent vasodilation and suppresses coronary microcirculation; which, in theory, can alter the outcome of a radionuclide scan. AIM: The present study was conducted with the aim to investigate the changes in blood glucose level of patients receiving dipyridamole for cardiac scan. MATERIALS AND METHODS: A total of 293 patients (85 men and 208 women, age: 60.59±10.43 years) were included in the study. Fasting Blood Glucose (FBG) was measured before and 8 min after dipyridamole (0.568 mg/kg) injection during myocardial perfusion imaging. The data in different groups were analysed by paired t-test. RESULTS: There was not a significant difference between first (106.89 ± 19.21mg/dL) and second (107.98 ± 17.57 mg/dL) FBG measurements (p= 0.293). However, when the patients were grouped based on the quartiles of first measurement, there was an increase in FBG following dipyridamole injection in the first quartile (mean difference: 7.15±21.27 mg/dL, p<0.01); in contrast, FBG levels showed a significant decrease after dipyridamole administration in the 4(th) quartile (mean difference: -9.53±18.20 mg/dL, p<0.001). The differences in 2(nd) and 3(rd) quartiles were negligible. The patients were divided into normal, ischemic and fixed lesions based on the outcome of scans, then the possible correlation of dipyridamole-induced FBG alteration and scan results were investigated. There were no significant difference between the FBG values before and after dipyridamole injection and the final outcome of scan. CONCLUSION: The effects of dipyridamole on blood glucose highly depend on the initial blood glucose level.

17.
Mol Imaging Radionucl Ther ; 25(1): 26-31, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-27299285

RESUMO

OBJECTIVE: The aim of the current study was to compare 180° and 360° data collection modes to measure end diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) values of the cardiac system by gated myocardial perfusion tomography. METHODS: Thirty-three patients underwent gated myocardial perfusion tomography. Single photon emission computed tomography data of patients' heart were acquired by 180°, 45° left posterior oblique to 45° right anterior oblique, and 360° to obtain EDV, ESV, EF and cardiac volume changes (V1, V2, V3, V4, V5, V6, V7 and V8) throughout each cardiac cycle. RESULTS: Results of the current study indicated that there were no significant differences between 180° and 360° angular sampling in terms of measuring EDV, ESV and EF in myocardial perfusion imaging. Cardiac volume change patterns during a cardiac cycle were also similar in 360° and 180° scans. We also observed that there was no difference in EDV, ESV and EF values between the group with stress induced by exercise and the group with stress imposed by dipyridamole. CONCLUSION: As there is no difference between 180°and 360° cardiac scanning in terms of EDV, ESV and EF, half-orbit scan is recommended to study these cardiac system parameters because it offers more comfort to patients and a shorter scanning time.

18.
Iran J Radiol ; 12(4): e14619, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26715978

RESUMO

BACKGROUND: The discrimination of inactive inflammatory processes from the active form of the disease is of great importance in the management of interstitial lung disease (ILD). OBJECTIVES: The aim of this study was to determine the efficacy of 99mTc-IgG scan for the detection of severity of disease compared to high-resolution computed tomography (HRCT) and pulmonary function test (PFT). PATIENTS AND METHODS: Eight known cases of ILD including four cases of Mustard gas (MG) intoxication and four patients with ILD of unknown cause were included in this study. A population of six patients without lung disease was considered as the control group. The patients underwent PFT and high-resolution computed tomography, followed by 99mTc-IgG scan. They were followed up for one year. 99mTc-IgG scan assessment of IgG uptake was accomplished both qualitatively (subjectively) and semiquantitatively. RESULTS: All eight ILD patients demonstrated a strong increase in 99mTc-IgG uptake in the lungs, compared to the control patients. The 99mTc-IgG scan scores were higher in the patient group (0.64[95% confidence interval(CI)=0.61-0.69])) than the control group (0.35 (0.35[95% CI=0.28-0.40]), (P<0.05)). In patients, a statistically significant positive correlation was detected between 99mTc-IgG scan and HRCT scores (Spearman's correlation coefficient = 0.92, P < 0.008). The 99mTc-Human Immunoglobulin (HIG) scores were not significantly correlated with PFT findings (including FVC, FEV1, FEV1/FVC), O2 saturation and age ( P values > 0.05). There were no significant correlations between 99mTc-IgG score and HRCT patterns including ground glass opacity, reticular fibrosis and honeycombing (P value > 0.05). CONCLUSION: The present results confirmed that 99mTc-IgG scan could be applied to detect the severity of pulmonary involvement, which was well correlated with HRCT findings. This data also showed that the 99mTc-IgG scan might be used as a complement to HRCT in the functional evaluation of the clinical status in ILD; however, further studies are recommended.

19.
Medicine (Baltimore) ; 94(47): e2082, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26632717

RESUMO

The differentiation of active inflammatory processes from an inactive form of the disease is of great value in the management of interstitial lung disease (ILD). The aim of this investigation was to assess the efficacy of 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI) scans in distinguishing the severity of the disease compared to radiological and clinical parameters.In total, 19 known cases of ILD were included in this study and were followed up for 1 year. Five patients without lung disease were considered as the control group. The patients underwent pulmonary function tests (PFTs) and high-resolution computed tomography scans, followed by 99mTc-MIBI scanning. The 99mTc-MIBI scans were analyzed either qualitatively (subjectively) or semiquantitatively.All 19 ILD patients demonstrated a strong increase in 99mTc-MIBI uptake in the lungs compared to the control group. The 99mTc-MIBI scan scores were higher in the patient group in both the early phase (0.24[0.19-0.31] vs 0.11[0.10-0.15], P < 0.05) and the delayed phase (0.15[0.09-0.27] vs 0.04[0.01-0.09], P < 0.05) compared with the control group. A positive correlation was detected between the 99mTc-MIBI scan and the high-resolution computed tomography (HRCT) scores (Spearman's correlation coefficient = 0.65, P < 0.02) in the early phase but not in the delayed phase in patients (P > 0.14). The 99mTc-MIBI scan scores were not significantly correlated with the PFT findings (P > 0.05). In total, 5 patients died and 14 patients were still alive over the 1-year follow-up period. There was also a significant difference between the uptake intensity of 99mTc-MIBI and the outcome in the early phase (dead: 0.32[0.29-0.43] vs alive: 0.21[0.18-0.24], P < 0.05) and delayed phase (dead: 0.27[0.22-0.28] vs alive: 0.10[0.07-0.19], P < 0.05).The washout rate was ~40 min starting from 20 min up to 60 min and this rate was significantly different in our 2 study groups (ILD: 46.61[15.61-50.39] vs NL: 70.91[27.09-116.36], P = 0.04).The present study demonstrated that 99mTc-MIBI lung scans might distinguish the severity of pulmonary involvement in early views, which were well correlated with HRCT findings. These results also revealed that 99mTc-MIBI lung scans might be used as a complement to other diagnostic and clinical examinations in terms of functional information in ILD; however, further investigations are strongly required.


Assuntos
Doenças Pulmonares Intersticiais/patologia , Pulmão/patologia , Cintilografia/métodos , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Sestamibi , Adulto , Feminino , Humanos , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
20.
Hell J Nucl Med ; 18(2): 160-2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26187218

RESUMO

In this report, we present the application of hepatobiliary scintigraphy using Tc-99m mebrofenin in the diagnosis of bronchobiliary fistula caused by a liver hydatid cyst, which penetrated the diaphragm. Hepatobiliary scintigraphy noticeably depicted the leakage of the tracer from the biliary system of the liver to the bronchial tree. Hepatobiliary scintigraphy stands as a robust modality in the accurate diagnosis and treatment planning of bronchobiliary fistulas.


Assuntos
Fístula Biliar/complicações , Fístula Biliar/diagnóstico por imagem , Fístula Brônquica/complicações , Fístula Brônquica/diagnóstico por imagem , Equinococose Hepática/complicações , Equinococose Hepática/diagnóstico por imagem , Compostos de Anilina , Sistema Biliar/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Glicina , Humanos , Iminoácidos , Pessoa de Meia-Idade , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
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