اختبار: الأشعة البوزيتورنية A multiple-choice quiz consists of: 10 QuestionsQuestions are selected randomly from a collection of 17 questions. More Questions You will get deferent questions every time you take the quiz. Correct AnswersThere could be more than one correct answer, select all that apply.Skip QuestionsYou are allowed to scroll backward and forward before submitting your answers.10 MinutesThe quiz has a time limit. Time's up You can still submit your answers after the allowed period of time has ended . When ready, click Next to start the quiz. Name (Required) Email (Optional) Twitter (Optional) 1. With the administration of oral contrast media for integrated Positron Emission Tomography/Computed Tomography (PET/CT) studies, CT-derived attenuation values are: Not performed Overestimated Not applicable Underestimated 2. The majority of radiation exposure to personnel performing PET/CT procedures comes from the: CT scanner Injected patient PET scanner Unopened dose pig 3. F-18 is a cyclotron-produced radioisotope with a half-life approximately of: 110 min. 101 min. 119 min. 11 min. 4. The time from F-18 fluorodeoxyglucose (FDG) administration to the time of data acquisition has been shown to have a marked effect on FDG uptake. An increased interval between the injection and imaging uptake time will DECREASE radiotracer concentration in: Muscle. Blood pool. Tumor. Bone marrow. 5. Before FDG administration, the patient relaxes in a waiting room to minimize muscular activity, and in so doing minimizes any physiological uptake of FDG in the muscles. Hyperventilation may cause increased uptake in the: The diaphragm Leg muscles The peritoneum Arm muscles 6. All of the following cellular mechanisms are responsible for malignant cells increased F-18 fluorodeoxyglucose accumulation EXCEPT: Increased intracellular hexokinase. Low glucose-6-phosphatase. Increased membrane transporters. Low mitotic rate. 7. High glucose levels may interfere with tumor targeting due to competitive inhibition of FDG uptake by d-glucose. FDG-PET study should not be recommended when the glucose level in the blood exceeds: 120 mg/dl. 200 mg/dl. 155 mg/dl. 175 mg/dl. 8. The elevated serum glucose level at the time of fluorodeoxyglucose (FDG) administration may decrease the sensitivity of the FDG-PET study. Althoguh intravenous bolus of insulin may effectively lower the serum glucose level, however induced hyperinsulinemia will: Decrease heart rate. Increase blood pressure. Induce hyperglycemia. Shunt glucose to skeletal and cardiac muscles. 9. F-18 FDG uptake in tumors correlates with tumor: Shape and reproducibility. Growth and viability. Size and contractility. Volume and stability. 10. The term “partial volume effect” is caused by the limited resolution of PET scanners and refers to phenomenon that make intensity values in images differ from what they ideally should be. The “hot” spot smaller than twice the resolution of the scanner will have total counts preserved and will appear: Larger with a higher activity concentration Smaller with a higher activity concentration Larger with a lower activity concentration Smaller with a lower activity concentration 1 out of 10 Time's upTime is Up! بواسطة ناصر المطيري|2021-09-20T14:26:18+03:00أبريل 15th, 2021|الأشعة البوزيترونية|لا توجد تعليقات شارك هذه الصفحة, واترك رأيك حول الموضوع باستخدام وسيلة التواصل التي تناسبك FacebookXLinkedInWhatsAppPinterestEmail عن: ناصر المطيري كبير أخصائيي الطب النووي في مستشفى حفر الباطن المركزي و مؤسس موقع نيوكليرمد. اترك تعليقاًCancel reply
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