NMTCB PET Positron Emission Tomography Specialty

What is the energy of annihilation photons detected in PET imaging?

• A140 keV
• B364 keV
• C511 keV
• D662 keV

What is the half-life of F-18 fluorodeoxyglucose (FDG)?

• A20 minutes
• B68 minutes
• C110 minutes
• D6 hours

What type of coincidence event occurs when two unrelated annihilation photons from different positron decays are detected simultaneously?

• ATrue coincidence
• BScatter coincidence
• CRandom coincidence
• DPrompt coincidence

Prior to an F-18 FDG PET scan, patients are typically instructed to fast for how long?

• A1-2 hours
• B4-6 hours
• C8-12 hours
• D24 hours

Which scintillation crystal is most commonly used in modern PET scanners due to its high light output and fast decay time?

• ABismuth germanate (BGO)
• BSodium iodide (NaI)
• CLutetium oxyorthosilicate (LSO)
• DCesium iodide (CsI)

What is the primary advantage of time-of-flight (TOF) PET technology?

• AIt eliminates the need for attenuation correction
• BIt reduces patient radiation dose by 50%
• CIt improves the signal-to-noise ratio of the reconstructed image
• DIt removes random coincidence events entirely

Rb-82 chloride is produced by which method?

• ACyclotron irradiation of O-18 water
• BSr-82/Rb-82 generator
• CNuclear reactor fission
• DCyclotron irradiation of Zn-68

What is the half-life of Rb-82?

• A10 seconds
• B76 seconds
• C10 minutes
• D68 minutes

What is the recommended maximum blood glucose level for a patient undergoing an FDG PET scan?

• A100 mg/dL
• B150 mg/dL
• C200 mg/dL
• D300 mg/dL

In PET/CT, what is the primary purpose of the CT component?

• ATo provide attenuation correction and anatomical localization
• BTo replace the PET emission scan entirely
• CTo perform radiation therapy planning only
• DTo measure blood flow independently of PET

What does SUV stand for in PET imaging?

• AStandard Uptake Variable
• BStandardized Uptake Value
• CSystemic Uptake Volume
• DSpecific Utilization Value

A misalignment between the PET and CT images in a PET/CT study most commonly results from which of the following?

• ADetector malfunction
• BPatient respiratory motion
• CIncorrect radiopharmaceutical dose
• DScanner room temperature fluctuations

Which of the following is a common artifact caused by metallic implants in PET/CT imaging?

• ARing artifacts on PET only
• BOvercorrection of attenuation leading to focal hot spots on PET
• CUndercorrection causing cold spots on CT
• DIncreased scatter on the raw CT images

What is the typical uptake period for F-18 FDG before PET imaging begins?

• A10-15 minutes
• B30-45 minutes
• C60-90 minutes
• D3-4 hours

Which PET radiopharmaceutical is used for imaging neuroendocrine tumors expressing somatostatin receptors?

• AF-18 FDG
• BGa-68 DOTATATE
• CRb-82 chloride
• DF-18 florbetapir

What is the most significant advantage of BGO (bismuth germanate) crystal over LSO for PET detection?

• AFaster scintillation decay time
• BHigher light output
• CHigher stopping power (detection efficiency) for 511 keV photons
• DBetter energy resolution

A PET technologist notices that the daily quality control phantom scan shows a uniformity variation exceeding 10%. What is the most appropriate next step?

• AProceed with patient scans and report the issue at the end of the day
• BPerform a normalization scan
• CImmediately begin scanning patients at reduced dose
• DIncrease the phantom activity and repeat the scan

In PET imaging, what is the coincidence timing window?

• AThe time between injection and scanning
• BThe time interval within which two detected photons are considered to originate from the…
• CThe time required for a positron to annihilate with an electron
• DThe duration of a single bed position acquisition

Which of the following radiopharmaceuticals is used for PET myocardial perfusion imaging and requires an on-site cyclotron?

• ARb-82 chloride
• BN-13 ammonia
• CF-18 FDG
• DGa-68 DOTATATE

What type of radiation shielding is most effective for 511 keV annihilation photons?

• ALead or tungsten
• BAluminum
• CPlexiglas (acrylic)
• DConcrete only

What is the purpose of iterative reconstruction algorithms (such as OSEM) in PET imaging?

• ATo increase scanner spatial resolution beyond the detector size
• BTo produce images with improved noise characteristics compared to filtered back projection
• CTo eliminate the need for attenuation correction
• DTo reduce the physical half-life of the radiotracer

Which regulatory body sets limits for occupational radiation exposure for PET technologists?

• AFDA
• BNRC (or Agreement State equivalent)
• CCDC
• DOSHA

During an FDG PET/CT scan, a patient's SUVmax in a pulmonary nodule measures 8.5. This value most likely represents:

• ANormal physiologic activity
• BBenign inflammatory process with certainty
• CHighly suspicious for malignancy
• DAn imaging artifact requiring repeat scanning

What is the primary mechanism of F-18 FDG uptake in malignant cells?

• APassive diffusion across the cell membrane
• BActive transport via glucose transporters (GLUTs) and metabolic trapping by hexokinase
• CReceptor-mediated endocytosis
• DBinding to tumor-specific surface antigens

What is the annual whole-body occupational dose limit for radiation workers set by the NRC?

• A10 mSv (1 rem)
• B50 mSv (5 rem)
• C100 mSv (10 rem)
• D500 mSv (50 rem)

A patient with insulin-dependent diabetes requires an FDG PET/CT scan. Which of the following is the best approach for managing the patient's blood glucose?

• AAdminister the patient's usual morning insulin dose and proceed with the scan
• BInstruct the patient to fast and hold short-acting insulin; check glucose before injectio…
• CCancel the scan because diabetic patients cannot undergo FDG PET imaging
• DAdminister extra insulin immediately before FDG injection to lower glucose rapidly

Which organ normally demonstrates the highest FDG uptake on a PET scan?

• ALiver
• BBrain
• CHeart
• DKidneys

What is the primary clinical application of F-18 sodium fluoride (NaF) PET?

• AMyocardial perfusion imaging
• BBrain amyloid imaging
• CSkeletal imaging for bone metastases
• DProstate-specific membrane antigen targeting

What is the purpose of a dose calibrator in a PET facility?

• ATo measure the energy spectrum of annihilation photons
• BTo measure the activity of radiopharmaceuticals before patient administration
• CTo calibrate the PET scanner detectors
• DTo monitor room radiation levels continuously

Which factor does NOT directly affect SUV measurement in PET imaging?

• APatient body weight
• BInjected dose of FDG
• CUptake time between injection and scanning
• DThe patient's blood type

Respiratory gating in PET/CT is primarily used to:

• AReduce the total scan time
• BMinimize respiratory motion artifacts, particularly in the thorax
• CIncrease the injected dose efficiency
• DEliminate the need for CT attenuation correction

What is the significance of the ALARA principle in PET radiation safety?

• AIt requires that all radiation exposure be completely eliminated
• BIt mandates keeping radiation doses As Low As Reasonably Achievable
• CIt specifies maximum patient dose limits for diagnostic imaging
• DIt applies only to pregnant radiation workers

In PET/MR imaging, what method is used for attenuation correction since MRI does not directly provide electron density information?

• AGermanium-68 transmission source scanning
• BMR-based tissue segmentation using Dixon or ultrashort echo time (UTE) sequences
• CUncorrected PET data with mathematical estimation
• DSeparate CT scan performed on a different day

A PET technologist spills a small amount of F-18 FDG on the preparation counter. What is the first step?

• AImmediately evacuate the entire department
• BNotify the radiation safety officer and contain the spill by covering it with absorbent m…
• CContinue working and clean up after all patients are scanned
• DPour water on the spill to dilute it

Which of the following factors contributes most to spatial resolution degradation in PET imaging?

• ACT tube current setting
• BPositron range and photon non-collinearity
• CPatient hydration status
• DRoom temperature during scanning

F-18 florbetapir (Amyvid) PET is clinically indicated for the detection of:

• ANeuroendocrine tumors
• BBeta-amyloid neuritic plaques in the brain
• CMyocardial viability
• DBone metastases

What is the primary advantage of using Ga-68 PSMA-11 PET/CT over conventional imaging for prostate cancer?

• AIt has a longer half-life than F-18 tracers
• BIt provides superior detection of biochemical recurrence and metastases at low PSA levels
• CIt eliminates the need for biopsy confirmation
• DIt can be used only after radiation therapy

What quality control test should be performed daily on a PET/CT scanner?

• AFull detector normalization with a Ge-68 cylinder
• BBlank scan and detector check/daily QC phantom scan
• CAnnual calibration of all photomultiplier tubes
• DCT tube output measurement with an ionization chamber

A whole-body FDG PET/CT scan typically covers which anatomical region?

• AHead only
• BSkull base to mid-thigh
• CChest and abdomen only
• DEntire body from vertex to toes

Which type of personal radiation monitoring device provides an immediate readout of radiation dose?

• AFilm badge
• BThermoluminescent dosimeter (TLD)
• CElectronic personal dosimeter (EPD)
• DRing badge

What is the purpose of performing a well counter constancy test in a PET facility?

• ATo measure patient dose before injection
• BTo verify that the well counter is maintaining consistent performance for sample counting
• CTo calibrate the PET scanner detectors
• DTo measure room background radiation levels

Dynamic PET imaging is most commonly used for which of the following applications?

• ARoutine whole-body oncology staging
• BQuantitative measurement of myocardial blood flow or cerebral metabolic rates
• CBone density measurement
• DCT dose optimization

What is the half-life of Ga-68?

• A13 seconds
• B68 minutes
• C110 minutes
• D12.7 hours

What is the primary purpose of the photomultiplier tube (PMT) in a PET detector?

• ATo absorb 511 keV photons directly
• BTo convert scintillation light photons into an amplified electrical signal
• CTo generate the coincidence timing window
• DTo provide attenuation correction data

In cardiac PET, what is the primary advantage of absolute myocardial blood flow (MBF) quantification over relative perfusion imaging?

• AIt requires less radiation dose
• BIt can detect balanced ischemia in three-vessel coronary artery disease
• CIt eliminates the need for pharmacologic stress testing
• DIt provides anatomical images of the coronary arteries

Which of the following is the correct procedure for disposing of radioactive waste in a PET facility?

• AAll radioactive waste must be transported to a licensed disposal site immediately
• BShort-lived PET isotopes (F-18) can be held for decay (minimum 10 half-lives) and then di…
• CAll radioactive waste should be flushed down the drain
• DRadioactive waste can be placed in regular trash if labeled with radioactive symbols

What phenomenon limits PET spatial resolution due to the positron traveling a finite distance before annihilation?

• APhoton attenuation
• BPositron range
• CCompton scatter
• DDead time