EFFECTIVE DOSE ESTIMATION IN WHOLE BODY 18F-FDG PET/CT IMAGING.

Positron emission tomography-computed tomography (PET-CT) with internal administration of the FDG-18 is characterized as a widespread functional imaging modality in diagnostic radiation medicine, which increases the patient effective doses owing to the presence of internal and external radiation sources. Hence, patient effective dose estimation has been pinpointed as a significant factor in radiation protection assessment. A large number of studies have been published in this regard, and various dosimetry methods have been surveyed. According to our previous research, 10 patients had participated in PET-CT scans with three static time sequences imaging. PET effective doses were estimated using a simple method derived from Anderson et al. and Kaushik et al. coefficients, and the CT effective doses were surveyed with a CTDI phantom and cylindrical ionization chamber. The CT dose was tripled owing to the three static time-sequences imaging. The effective doses were calculated using different coefficients and the results of the PET effective doses were compared. The PET-CT effective dose was varied from 17.14 to 18.42 mSv based on Kaushik et al. coefficients which were measured for one low-dose CT scan. This study aimed to survey simple PET-CT effective dose estimation using three static-time imaging approaches which increases the total patient effective doses.

Evaluation of Blood Parameters Alteration Following Low-dose Radiation Induced by Myocardial Perfusion Imaging.

INTRODUCTION: With increasing the usage of myocardial perfusion imaging (MPI) for the diagnosis of ischemic heart disease, we aimed to evaluate the side effects of low-dose radiation induced by this technique on blood elements, especially proteins and liver function factors. MATERIAL AND METHODS: 40 eligible patients (Mean age: 54.62±10.35, 22 female and 18 male), who had referred to the nuclear medicine department for MPI from May till August 2014, were enrolled in the study. A blood sample was taken from each patient just before and 24 hours after the injection of 740Mbq of Tecnetium-99m Methoxy isobutyl isonitrile (99mTc-MIBI) in the rest phase of the MPI in a reference medical laboratory; blood tests included total protein (TP), albumin (Alb), globulin (Glo), aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), direct bilirubin (D.Bili), total bilirubin (T.Bili), serum iron (SI), total iron bounding capacity (TIBC), Albumin globulin ratioA/G ratio), and complete blood count (CBC). RESULTS: Injection of 740Mbq99mTc-MIBI caused a significant increase in serum levels of AST (p= 0.001), ALT (p= 0.001), SI (p= 0.030), TIBC (p= 0.003) and A/G Ratio (p= 0.020). However, following radiotracer injection, a significant decrease was noted in the serum levels of TP (p= 0.002), Alb (p= 0.014), Glo(p= 0.002), ALP (p= 0.001), D.Bili (p= 0.003) and T.Bili (p= 0.000). CONCLUSION: Due to increased usage of MPI, our data highlights the importance of monitoring the clinical and paraclinical effects of the procedure on vital organs and physiological pathways to reduce their adverse effects.

Non-invasive glycaemia blood measurements by electromagnetic sensor: study in static and dynamic blood circulation.

In this paper, we present the results of non-invasive blood glycaemia measurements. The blood used in the measurements was calf blood. The measurement method uses an electromagnetic sensor based on eddy currents, which allows the detection of blood glycaemia levels through the variation of the dielectric parameters of the blood. A change in blood glucose concentration causes a variation in the dielectric parameters, in particular conductivity. Detection is only possible at a resonant frequency. The measurements were taken in a static and dynamic state (with and without circulation of blood). The blood is inside a plastic tube placed within the sensor and is surrounded by gelatine, which simulates muscular tissue. The plastic tube simulates the vein where blood circulation occurs. The in vitro results in both cases (static and dynamic) are provided. Under unfavourable conditions we can detect a change of +/- 2 g/l of glucose. We present and discuss these results.