Emission computed tomography test phantoms: a review

It is vital to assess the performance of emission computed tomography (ECT) systems prior to their use for clinical examinations. Generally, performance tests of ECT systems are time-consuming, expensive and require more than one phantom to scan and then analyse the data. There is non-availability of such type of phantoms that can provide all necessary data for performance of some quality control (QC) tests from a single scan data. In this paper, commercially available emission computed tomography (ECT) phantoms are thoroughly reviewed. Thus,designing and construction of a time-saving and cost-effective new compact ECT phantom has been suggested

MRI of corpus callosum in patients with autism spectrum disorder in Kuantan

OBjective: To study the integrity of the corpus callosum among autistic children population in Kuantan, Pahang, Malaysia, which is determined by MRI’s diffusion tensor imaging (DTI) parameters, fractional anisotropy (FA) and radial diffusivity (RD). These param- eters represent the direction dependence of water molecules diffusion within the measured tissues. As corpus callosum is saturated with brain white matter tracts, the water molecules diffusion here will be direction dependent. Studies involving foreign populations have shown that there is distortion in the corpus callosum’s DTI parameters in autistic population indicative of microstructural distor- tion. Whether similar findings will be observed in our local autistic population still remains a question. Other gross corpus callosum parameters such as its thickness, length and size are also studied. Materials & Methods: 28 randomly selected autistic children under the International Islamic University Malaysia Medical Centre (IIUMMC), Kuantan follow-up are subjected to MRI scan. Limited MRI sequences including DTI are obtained and analysed. FA, RD, midsagittal thickness at the genu, body and splenium of the corpus callosum as well as its midsagittal length and size are measured. Data are tabulated according to age followed by statistical analysis. Results: A weak negative correlation is found between the age and the FA of the corpus callosum. Other parameters such as the thickness, length and size show weak positive correlation with age. Conclusion: Although the correlation is weak, our study shows that there is evidence of distortion of corpus callosum white matter microstructure in children with autism spectrum disorder in Kuantan, Pahang

Ethical justification in medical futility and advanced medical directive from the Islamic perspective

Introduction: Medical futility and advanced medical directive are related issues in end-of-life medical decisions that present challenge to doctors and patients in terminal condition and to doctors and family members of patients who are critically ill in the ICU. Materials and Methods: A qualitative study comprises of literature search and an in-depth interview of experts was carried out to determine the clinical situations in medical futility and the ethical considerations from the Islamic perspective that justify forgoing medical treatment and also the practice of advanced medical directives in the country. Results: In such scenarios, clinical data must be interpreted alongside patient values, as well as the physicians’ ethical commitments. From the Islamic perspective, doctors are the authorised person to diagnose medical futility and forgo medical treatment. Forgoing treatment is permissible as long as it conforms to the maqasid and qawaid al-shariah principles that guide the decision-making process. The practice of advanced medical directive is still at its infancy in this country. From the Islamic perspective, upon considering the maqasid and qawaid al-shariah principles, it should be permissible and its practice should be encouraged as it assists the doctors and the surrogate decision-maker to decide to the withdrawal of treatment. Conclusion: Ethical justification on medical futility conforms to the maqasid and qawaid al-shariah principles and forgoing medical treatment is permissible in Islam. Advanced medical directive assists in the decision-making of forgoing treatment in the presence of utility and thus its practice should be promoted

Dynamic renal scintigraphy: technetium99m (Tc99m) diethylenetriaminepentaacetic Acid (DTPA), breast cancer center of International Islamic University Malaysia (IIUM) experience

Technetium99m Diethylenetriaminepenta acetic acid (DTPA) has been used in renal imaging over the last few decades. It is one of excellence radiotracer for evaluation of the renal parenchymal function. Breast cancer center designed a prospective study to evaluate the ability of Tc99m DTPA scintigraphy to detect renal parenchymal functions in adult patient with Endocytosis. The purpose of this paper is to provide a better understanding of the use of Tc99m DTPA as a tool in dynamic renal imaging and highlight Breast cancer center, IIUM experience using Tc99m DTPA for the assessment of renal parenchymal function. Retrospective analysis of 73 patients from March 2015 to December 2016 using Tc99m DTPA renal scintigraphy is presented in this study. The clinical profile and scintigraphy findings of all the patients were analyzed. Dynamic renal scintigraphy is superior in measuring kidney function (GFR, ERPF), compared to investigations based on the serum creatinine value. Number of uses in of 99mTc-DTPA indicated that this radio radiopharmaceuticals quality control is very crucial in preparation and need to ensure it efficiency and safety when administered to patients. Tc99m DTPA remains a very useful tool to assess renal parenchymal function and specific renal pathology. CTc99m DTPA scintigraphy diagnostic methods can improve the sensitivity and specificity to establish renal parenchymal function. During the follow-up the renal parenchymal functions, improved in all cases. In IIUM breast cancer center present here and experience of radionuclide studies in the evaluation of renal parenchymal function at the Nuclear Medical Centre

51-Chromiumethylenediaminetetraacetic acid (51Cr-EDTA) glomerular filtration Rate (GFR) analysis: comparing two blood sampling with multiple blood sampling

The glomerular filtration rate (GFR) is the commonest method used to quantify renal function. Chromium-51-Ethylenediaminetetraaceticacid (51Cr-EDTA) plasma clearance has been accepted as a gold standard method in measuring GFR. Several methods have been proposed in which the glomerular filtration rate is estimated from using only one or two blood samples to using multiple blood samples. The purpose of this study is to determine the accuracy of using two blood samples compared to multiple blood samples, for calculation of GFR by the 51Cr-EDTA method. In addition, the study aimed to determine the best combination time of two blood sampling and correlation with gender and ethnicity of the patients. 51Cr-EDTA tracer solution is injected into a vein in the upper arm. Six mls of whole blood is then drawn from the opposite arm at 120, 150, 180 and 240 minutes, centrifuged and 2 ml aliquots of plasma are pipetted and counted for a period of 5 minute each time, in an automatic gamma well counter. GFR is calculated by measuring Cr-EDTA plasma clearance using slope intercept method. The patients’ height and weight is used to correct the GFR to body surface area. Correlations of the values are tested by Pearson and Intraclass correlation, and mean and standard deviation derived from pair t-test. All time point combinations using two blood sampling shows a high correlation with multiple blood sampling method (p value < 0.001, r = 0.909 to 0.989). The best combination using two blood sampling is at 2 and 4 hour time point (r = 0.989 with 99% consistency). 51Cr-EDTA GFR estimation using two blood sampling method is accurate and reliable. The two and four hour time point is found to be the best. Gender and ethnicity does not influence GFR estimation using two blood sampling method

Radionuclide study in gastroparesis: Is it still relevant?

The incidence of gastroparesis in Malaysia is not well documented. It is diagnosed based on clinical symptoms and exclusion of the obstruction. Here a case of a young adult woman with type 1 diabetes mellitus suffering severe gastrointestinal symptoms. In this case, radionuclide scintigraphy is used as one of the investigation to confirm the diagnosis of gastroparesis

Tc-99m myocardial SPECT image quality improvement with a physical filter as scattered gamma photon absorber: phantom study

Introduction: Presence of scattered gamma photons in the projection data of Tc-99m Myocardial SPECT degrades the image quality. Thus, the efficacy of SPECT in patient studies is hampered. This work is aimed at enhancing the image quality and accuracy in measurement of cold defect size by pre-filtering of scattered gamma photons with physical filter. Material and method: GE Infinia II gamma camera with LEHR collimator was used. A flat sheet of Aluminum 0.1 mm thick, 55 cm x 44 cm sized was mounted on the outer surface of collimator. Carlson’s phantom with cardiac insert simulating the left ventricle was scanned. A polystyrene cold defect (9.8 mm x 9.8 mm x 9.8 mm) was placed at the anterior side of the myocardial wall. Water was filled into myocardial wall chamber; Tc-99m with concentration of 3.9μCi/ml was injected. It was inserted into the cylindrical tank after water was filled. Tc-99m radioactivity with 1.1μCi/ml concentration as background was administered. The chamber was positioned according to the orientation of human heart. Energy window (20%) centred at 140 keV was adjusted. Data were registered into a 128x128 matrix with sixty projections with and without physical filter opting step-and-shoot acquisition extended in a 180o arc from 45˚ right anterior oblique to 45˚ left posterior oblique. Filtered back projection method was used for image reconstruction by selecting Butterworth filter of order 10 and cut-off frequency 0.40/cm. Chang’s attenuation correction was applied. Results: Cold defect size measurement and image contour analysis of short axis views show significant improvement (p<0.05) in the accuracy in defect size and image quality with physical filter. Our study demonstrates that this technique is effective in removing scattered gamma photons from SPECT projection data. Conclusion: Physical filter technique may be implemented in Tc-99m myocardial SPECT clinical studies. Yet still, further studies are required with different phantoms which mimic the human heart closely

OSCE Year 4 IIUM (MBBS) Department of Radiology Kulliyyah of Medicine -Set 2

The article is a past year OSCE questions for end od posting, examination for undergraduate medical students during, their specialised postin

OSCE for year 4 MBBS IIUM set 1

The article is a past year OSCE questions for end of posting examination