Nuclear Medicine Lab Visit - Case Study Example

Nuclear Medicine Lab Visit Name Institution Nuclear Medicine Lab Visit 1. Description of set-up for Gamma Camera Image Quality Experiments Gamma Camera Image Quality Experiments setup involves selecting the materials to be used during the experiment such as Macintosh Computers, Gamma camera and Acquisition Console, and parallel hole and pinhole collimators. The setting of the equipment involves turning the acquisition console and selecting the right program such as ‘Gamma 600’. Spatial resolution is measured by imaging a small source of light and determining the actual width at half maximum of the peak activity. The pixel size is determined and the location of the pixel with the highest counts is determined on the first image. The distance between the two locations is established in pixels. In the case of the collimator, parallel hole collimator is removed and attached to pinhole collimator. Pinhole geometry such as width of the circular object is determined and perform the test for camera to generate the curve for 20% count-loss. The materials used include: copper plates, 99m Tc 1mCi, the collimator is removed from the source holder and the windows are set at 20%. The thickness of the copper plates is determined and the total count is determined. The attenuation coefficient of the copper is determined and a graph is plotted for count rates versus thickness and the expected counts. The count rate at which the camera loses 20% of the expected outcomes is determined. While the collimator is off, the uniformity of the field is determined. Copper filters are used to prevent dead time losses. The camera is moved to a maximum height and a 4 minute image is obtained and the mean and standard deviations of the edges are determined. The results of experiment 1 with respect to the relevant theory is that the gamma camera image quality experiment will enable understanding the number of counts of the specimen under investigation thus understanding the specimen in details and interpreting the outcomes in an accurate manner. The findings will also be important with respect to the theory because when the quality of the gamma camera is known, it will be possible. This is because the camera with the right resolution will enable counting the images under observation. Figure 1. Image obtained when using the Gamma Camera Figure 1. Determination of pinhole geometry of the gamma camera during the experiment The results of Experiment 2 with respect to the relevant theory is that the theory will enable establishment of the right camera that has particular focal distance which can be easily determined by the observer so that the image can be resolved at the right distance. The camera will also be selected based on the qualities that enable more details of the specimen to be viewed thus understanding the details of the specimen and enabling their analysis. Figure 2. Gamma Camera Image Quality Experiment Setups The results obtained the experiments are of clinical importance because they enable understanding of the magnitude of the uniformity of the specimen under observation during the creation of artifacts, thus understanding the methods through which generation of ring artifacts takes place. This is achieved based on the assumption that the gamma camera has a perfect uniformity. It also ensures the right distance between the object and the camera is set during the back projection (Hine, 2013). The resulting ring is obtained in the size and number expected by the observer. The theoretical experiments are also used to ensure quality of the differential uniformity to ensure there are no ring artifacts during clinical studies. Uniformity correction is important in reducing non-uniformities in the systems to a low level that the resulting artifacts from residual non-uniformities are not equal to the image noise and cannot be viewed in the reconstructed data. The clinical professionals in the use of gamma cameras can also provide the manufacturers with specific qualities of the gamma camera to be used during experiments. The manufacturers can use the procedures in the experiment to design cameras which enable specific qualities of the camera to be achieved (Leo, 2012). The choice of matrix is of relevance in a collimator because it enables the achievement of the resolutions of other parameters because the parameters various according to the choice of matrix. Furthermore, the count density in a collimator is of relevance in understanding any abnormality within an image. In patients who are not cooperative or undergoing pain and less able to tolerate longer scan periods, short imaging times are recommended. The distance from the collimator is of importance in clinical practice because it determines the number of specimens in the field of view during examination with the collimator. When the distance from the collimator is changed beyond 30 cm range, its resolution is affected. In addition, if the patient-collimator is not minimized, suboptimal image quality can be obtained. 2. Description of laboratory processes for Glomerular Filtration Rate test The Glomerula filtration test enables understanding the functioning the kidneys and the extent to which it is able to remove wastes from the body quickly. It involves the use of a small sample of radioactive material that enables measurement of the kidney filtering capability. The test is done in the nuclear medicine department (Ljungberg et al. 2012). During the test, the patient is asked not to take medications that have the potential to affect the outcome of the test. This is followed by the insertion of intravenous lines on each arm. One of the lines will be used or the provision of radioactive drug while the other is used to take blood samples. The line used as the passage for blood samples is referred to as the heparin lock. The device enables measuring blood samples without the use of needle sticks. The next step involves the injection of radioactive materials into the blood of the patient through one of the I.V. lines that have been inserted. This is followed by drawing two blood specimens 1 hour after injecting and 3 hours after the injection. When the second blood sample has been drawn, the IV lines are removed. After the test, patients usually do not feel any impact of the tests and may return home or to their rooms. An example of a special consideration to be made during glomerula test is to prevent the performance of the test in pregnant women due to the destructive impact of the radioactive materials used. Figure 3. Graph of Serum Creatinine during glomerula test Figure 4. Insertion of the IV lines during the glomerula test When it is discovered that one of the sample volumes used during glomerula filter test is incorrect, the quantity used to detect this is the amount of sample from the device with the recommended volume of the sample (Mann et al. 2014). Another sampling error that can be detected using this method is the collection of samples that not undergone filtration. This is because, this sample has not passed through the glomerula and it is not possible to know whether the glomerula filtration has been affected or not. Figure 5. Comparison of Graphs befire and after glomerula tests Calculation of the GFR. During the calculation of GFT, the formulr used is: GFR = 141 × min (Scr /κ, 1)α × max(Scr /κ, 1)-1.209 × 0.993Age × 1.018 [if female] × 1.159 [if black] In the above equation: Scr is the amount of serum creatinine κ is 0.7 among female patients and 0.9 among male patients α is -0.329 among female patients and -0.411 among male patients min provides the least of Scr /κ or 1, and max provides the highest of Scr /κ or 1. For instance, a 45 years old black male person with Scr of 0.6 will have a GFR of 141 x (0.6/1)-0.411 x (0.6/1)-1.209 x 0.993 45 x 1.159 The GFR will be = 141 x1.233 x 0.7290 x 1.159 = 145.70 milliliters per minute or mL/m. The importance of quality control during glomerula filtrate test is that it ensures variable differences are not experienced when the SBS and ASI clearances are used based on the clearance values (Moreno, 2013). This is because, the impact of error on sample of plasma also changes in the same manner as the clearance values. An example of a quality control test for glomerula filtrate is the volume distribution test. This is the process where an assessment is done on the volume distribution and half life values in the process of conducting the glomerula filtration test. This is achieved by use of well-defined data for VD and half life as QC checks (Perl et al. 2012). Furthermore, QC involves the use of Tc-DTPA as a method of enhancing the understanding of adult Tc-DTPA measurements. 3. The of set-up for Radionuclide Calibrator Experiments The set-up for image processing is composed of the dose calibrator. This refers to a chamber filled with gas that measures the ionizing radiation exposure in a particular radioscopy. These devices are mainly filled with gases and contain wells in the centers and are used for various processes of radioactive administration (Shah et al. 2012). The chambers are filled with argon under high pressure such as 30 atmospheres. The collection of ions by the chamber is achieved by a series of interactions in the applied voltage. When ionization has occurred, there is the movement of positive charges towards the cathode. As a result, a voltage is created that keeps the anode and cathode functional and enables calibration memory to be achieved. In practical application, these calibrators are mainly used during the calibration of dose as a factor of a particular rib nuclide. Radiopharmacies and departments that specialize in nuclear medicines generally assay patients in glass vials use plastic syringes. Physiological gating and quantitative ROI analysis are also used in nuclear medicine in a number of ways. They are methods that reduce brain motion when spectral data is involved. For instance, the use of retrospective gating has been implemented to acquire spectral data under the suppression of water (Stephens et al. 2012). Each line of data is phased in stages in the unsuppressed water signal that take place in various parts of the cardiac cycle. In the magnetic resonance imaging process (MI) the changes in the global phase at various time intervals compared with the cardiac cycle overall mean is used. The physiologic movement of the brain results into changes to phase of the water signal. The highest change of the global phase of water signal from the frontal while matter takes place during the systole in the ventricles. Cardiac structures can be evaluated using cardiograph that enables understanding the manner in which they move (Wall et al. 2014). A significant number of clinical doses are determined by the activity of the left ventricle. The study of the myocardial infarction is done by manual segmentation process of the ventricular cavity by use of a series of images. The following is the generated annotated time-activity curve Figure 6. Slope of the generated annotated time-activity curve Slppe (61143-51402)/(366-297) Gradient = 141.17 When compared with semi-automatic processing, it is found that image segmentation is achieved by use of morphological operations. Morphological filtering is used in combination with edge enhancement to filer sections of the left ventricle. Radial search algorithm m has also been used on the context of temporal data that enables improvement of segmentation quality. Another method that has been proposed is the time-averaging deionizing process on the basis of estimation of motion during frame rejection. Processing stage has also been suggested based on fusion of images to enhance the effectiveness of watershed segmentation. 4. Procedure through which the images were obtained During the MUGA scan, the patient’s Left ventricle was scanned to determine the Left Ventricular Ejection Fraction (LVEF). This was achieved by first injecting the patient with 99mTcO4- . The Gamma camera was then placed on top of the patient to provide the separation in the image between the left and right ventricles of the heart. The region of interest was determined by selecting a region in the left ventricle when it is in diastolic phase. The data was used to determine the time-activity curve for the data. The following is the time-activity curve that was obtained. Figure 6. Time-Curve for the data The clinical implication of interoperateor variability is the difference in determining the number of counts of the defects established in a patient. When there is a large variability in the quantification of reversible apical perfusion defects, the clinical understanding may be affected and false conclusions may be made. References Endler, P.C. and Schulte, J. eds., 2013. Ultra high dilution: physiology and physics. Springer Science & Business Media. Flynn, E.H. ed., 2013. Cephalosporins and penicillins: chemistry and biology. Elsevier. 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The clonal and mutational evolution spectrum of primary triple-negative breast cancers.Nature, 486(7403), pp.395-399. Stephens, P.J., Tarpey, P.S., Davies, H., Van Loo, P., Greenman, C., Wedge, D.C., Nik-Zainal, S., Martin, S., Varela, I., Bignell, G.R. and Yates, L.R., 2012. The landscape of cancer genes and mutational processes in breast cancer. Nature, 486(7403), pp.400-404. Wall, B.F., Kendall, G.M., Edwards, A.A., Bouffler, S., Muirhead, C.R. and Meara, J.R., 2014. What are the risks from medical X-rays and other low dose radiation?. The British journal of radiology. Read More