Suchergebnisse

This study aims to investigate, using patient studies, the impact of Injected Dose (ID), Body Mass Index (BMI), and image noise assessments in PET imaging. This study included 59 liver cancer patients weighing between 45 and 107 kg. After intravenously injecting 0.1 millicurie (mCi) of 18F-FDG per kilogram of body weight, PET scans were obtained for 1, 1.5, and 3 min/bed position based on the patient's weight.
Weight, height, and body mass index were calculated using a spreadsheet.
Five regions of interest (ROIs) were placed at the same site in the liver, which was considered to have a homogeneous metabolism, in five successive slices of PET/CT scans to determine the mean uptake (signal) values and their standard deviation (noise). The ratio of both gives the liver's Signal-to-Noise Ratio (SNR).
Graphs were created to determine the relationship between these characteristics. The plots demonstrated that the dose injected increased when body weight and/or BMI increased, and that the SNR fell even as the dose administered increased. This is owing to the fact that heavier patients having a higher administered dose and, have a lower SNR even when greater 18F-FDG doses are delivered. These data indicate that the image quality, as measured by the SNR, is inferior in heavier persons compared to those who are thinner.

Background: Left ventricular function and volumes have major diagnostic and prognostic importance in patients with various cardiac diseases, such as ischemic heart disease which is a life-threatening heart disease condition characterized by systolic dysfunction and a decrease in cardiac output.
According to left ventricular ejection fraction, the degree of ischemic heart disease was classified as mild, moderate, and severe. To determine cardiac function and hemodynamics, the echocardiography technique is used, which is a noninvasive diagnostic method.
Patients and Methods: The study included 216 patients between 25 and 75 years old; 121 males and 95 females; 265 normal individuals (age range: 25 to 75 years old); 84 males and 181 females. Doppler echocardiography was used to assess left ventricular function. The measurements included left ventricular end-diastole diameter (LVIDd), left ventricular end-systole diameter (LVIDs), and left ventricular ejection fraction (LVEF%).
Results show a significant correlation in the values of EDV, ESV and LVEF (all: p < 0.05). The change difference in left ventricular ejection fraction (LVEF) was (61.88%), (47.57%), and (36.76%), respectively, for all degrees of ischemia. While the change difference in left ventricular end diastolic volume (LVEDV)between patients and control groups was (173.38%), (248.83%), and (289.82%), respectively. On the other hand, the change in left ventricular end systolic volume (LVESV) was (258.73%), (495.13%), and (569.72%), respectively, for all degree of ischemia.
Conclusion: The findings suggest that diastolic dysfunction is more common in patients than in healthy people. This could be due to the adverse effects of ischemic heart disease on the cardiac muscle. These changes in left ventricular structure may include left ventricular hypertrophy, increase in stiffness, and reduction in compliance.

Both obesity and diabetes are major problems for the public's health. Both are known to contribute to the development of atrial cardiomyopathy. However, the consequences of obesity on the function of the left atrium(LA) in diabetic individuals have not been determined as of yet. The aim of this study is to compare the peak atrial longitudinal strain (PALS) measured by two-dimensional (2D) speckle tracking in obese versus non-obese diabetic Iraqi patients. For a study that was designed to be cross-sectional, the data collection period lasted for a total of ten months. In this study, the participants had to have diabetes mellitus type 2. A comparison was made between patients who were obese and patients who were not obese using 2-D speckle tracking to measure the peak left atrial longitudinal strain. Several additional factors, such as age, gender, body mass index, conventional echocardiographic parameters, and volume-derived LA function, were investigated during this study. A total of 59 patients participated in this study. The ratio of males to females was exactly 1:1.5, and the average age was (54 ± 9.4) years old. Coexistent systemic arterial hypertension was observed in 25 % of the study population. Patients with type 2 diabetes mellitus and obesity had ad higher E/e` ratio and lower PALS than patients with type 2 diabetes mellitus without obesity, whereas all other parameters were statistically non-significant (EF, E/A, S prime, LA volume index). It was found that the peak longitudinal strain of the LA, which was measured using 2-D speckle tracking, was lower in the obese diabetic individuals. This was in contrast to diabetic people, who did not have obesity issues. An evaluation of the global strain in the left atrium can help in the early detection of remodeling and dysfunction in the left atrium if it is compared to the size of the left atrium and the filling pressures of the left ventricle, both of which are respectively determined by the E/e' ratio and the left atrial volume.

Background: 18F-FDG positron emission tomography (PET) has established itself in the field of oncology and it is useful in the initial staging and follow-up of a variety of malignancies. Significant thyroid uptake is often identified as an accidental finding on whole-body positron emission tomography for non-thyroid disease.
Aim of this study: to investigate the effect of 18F-FDG on thyroid gland function after performing PET scan compared to thyroid function prior to scan.
Materials and Methods: 43 subjects who had an 18F-FDG PET scan as part of a cancer screening program participated in this study. All cancers are diagnosed using 18F-FDG, except for prostate cancer, brain cancer and neuro-endocrine tumors, which are diagnosed using Ga-68. Thyroid stimulating hormone (TSH), thyroxine (T4), and triiodothyronine (T3) were measured.
Results: Clinical information and results of thyroid function tests were available for 43 patients. Twenty- three out of 43 patients (53.48%) had abnormally high TSH levels with incident hypothyroidism, while 20 out of 43 patients (46.51%) had abnormally low TSH levels with incident hyperthyroidism, and the association was significant (p <0.05).
Conclusion: Thyroid hormone abnormality is strongly associated with the degree of diffuse thyroid uptake on 18F-FDG PET. As a result, an autoimmune process could be the most likely pathological cause of diffuse thyroid uptake.

Background: Ischemic heart disease is a major cause of the diastolic heart failure. Risk of heart failures was increased with microvascular coronary disease, which is characterized by left ventricular stiffness with impaired relaxation and reduced compliance. Aim of this study is to estimate the effect of the severity of myocardium ischemia on the left ventricle ejection fraction and left ventricular volume using SPECT with 99mTc MIBI and to compare the results with the echocardiography. The study included 117 subjects with ischemic heart disease were examined using SPECT and echocardiography techniques. The following parameters were measured: left ventricular end systolic volume (LVESV) , left ventricular end diastolic volume (LVEDV) , and left ventricular ejection fraction (LVEF). Results show that the change difference in EDV between the two technique was (98.79%) with insignificant (p > 0.05). While the change in the LVEF% between both groups was (105.40%) with significant (p <0.05). On the other hand, the difference in ESV and EDV/ESV ratio for both groups were (95.52%), and (103.61%) respectively with insignificant (p >0.05). It was concluded that SPECT with 99mTc MIBI had a good relation with the echocardiography technique for evaluation of the left ventricular ejection fraction and the left ventricular volumes. The results showed that LVEF was decreased in patients with severe ischemic disease.

The purpose of this study is to measure doses delivered at different depths in water phantom at vertical position in comparison with the actual planning in order to verify the dose delivered to the tumor in addition to the measurement of the effect penumbra dose to assess the dose leaking to the healthy soft tissue.
Percentage depth dose (PDD) values was measured at field sizes (5×5,10×10,15×15, and 20×20) cm2, and the depth dose was measured between (0-16) cm deep at 4cm intervals, for both energies 6 MeV and 10 MeV X-ray beam. Other readings were taken at different distances 1cm and 2cm outside of the actual beam in orthogonal directions at depth of 4 cm. These measurements were designed to measure the penumbra dose produced outside the central beam.
Results show that the high similarity between water phantom and actual tissue for this reason water is taken as phantom for Quality Assurance (QA) and calculation the depth dose. The similar results may appear strange as the actual planning depth dose is taken in the chest wall where there is bone and soft tissue. The increase in the field size, increases the percentage of surface dose, this could be caused by an increase in the amount of scattering in the larger fields. There is almost no difference in depth dose between homogenous and non homogenous planning also similar to the water phantom. Because of higher photon energy 6MeV and 10MeV the bone has no influence in absorption from the soft tissue. A slight change in the depth dose with increase in the field size may be caused by the scattered radiation.