QUESTIONS AND ANSWERS 100%
CORRECT
Mixed Attentuation - ANSWER-Malignant Pulmonary Nodules on CT are characterized
by:
Reed-Sternberg Cells - ANSWER-Hodkin's Lymphoma is separated from other
Lymphomas by the presence of:
Acetylecholinestrearse Inhibitors
N-methyl-D-aspartate receptor antagonists - ANSWER-Two types of Alzheimer's
mediciation:
Left Subclavian Vein - ANSWER-Lymphatic Drainage for most of the body is via:
Erythropoietin - ANSWER-Hormone made in kidney's that signals the bone marrow to
make more RBCs:
Pair Production - ANSWER-2 electrons
One -, one +, from a pulse of electromagnetic energy traveling through matter
Opacity - ANSWER-Any area that preferentially attenuates x-rays
Appears more opaque than surrounding area
Ligand - ANSWER-An ion or molecule that binds to a central metal atom to form a
coordination complex
Isomeric transition - ANSWER-Nucleus of metastable isotope has an elevated energy
state and releases energy via gamma ray
Internal Conversion - ANSWER-Higher to Lower Energy w/o accompanying photon
Transition of energy w/i a molecule or atom
Renal Cancer - ANSWER-Affects woman >65
Renal Cell carcinomas mostly
Wilm's Tumor (pediatric)
covered under guidlines
Pancreatic Cancer - ANSWER-Most begins in ducts
Spreads to peritoneum, liver, lungs
Imaging neck to pelvis
,Covered under CMS NCD
Portal Vein and Hepatic Artery - ANSWER-The Liver primarily receives blood from:
Gastric Cancer - ANSWER-Men >65
Cardia, fundus, corpus, antrum, pylorus
Imaging Neck to Lower Pelvis
Five layers; mucosa, submucosa, muscularis, subserosa, serosa
Cells of Cajal - ANSWER-Pacemaker of GI Tract
Staging, Restaging, Monitoring response to theraphy - ANSWER-Breast Cancer CMS
coverage
Initial or Subsequent treatment strategy - ANSWER-Lung Cancer CMS coverage
Non-Small Cell
-More Common
-Spreads slowly
-Bone, Liver, Brain, Adrenal Glands
Small Cell
-Rapid Growth - ANSWER-Two major types of Lung Cancer:
Esophageal Cancer - ANSWER-Affects men more than women
>65 years
Squamous cell and mucinoid
Neck to pelvis imaging
Esophageal Cancer coverage - ANSWER-Initial Treatment, restaging, response to
therapy, recurrance
Thalamus - ANSWER-Brain structure described as "sensory relay"
Lipophilicity - ANSWER-Physiochemical property of a PET tracer that decides it's ability
to enter the brain and label the target receptor or enzyme:
F-18 Flurpiridaz - ANSWER-Binds to mitochondrial complex 1
Used for myocardial perfusion imaging
Nucleophillic Substitution and Purification
Performed similar to Tc-99m Rest/Stress
Negatrons and Positrons - ANSWER-Beta particles are electrons that contain
_____________ and ____________.
Electron Capture or Positron decay - ANSWER-Proton rich nuclei decay either by
_____________ or ______________ .
,1/3
ex: F-18 Max = 635 KeV Mean = 210 KeV - ANSWER-Mean energy of an ejected
positron is about ___________ of the max energy.
Decrease Resolution - ANSWER-Longer range of travel for a positron before
annihilation will ___________ resolution.
Positron emitted from atom w/ high kin. energy
Slows, combines w/ electron
Forms postironium briefly, spin
Mass is converted to energy, release two 511 KeV photons - ANSWER-Annihilation
Reaction
2 mm
0.25 degree deviation - ANSWER-Non-colinearity results in blurring effect on clinical
PET scanners of approximately _____ mm and angle of _____ deviation from 180.
Gas-Filled
Anode and Cathode
Operates at Low Voltage - ANSWER-Ionization chamber is a ____________ detector
w/ a ______________ and ______________ .
National Institute of Standards and Technology ( NIST) - ANSWER-Ionization chamber
is calibrated annually using a _____________
source so that exposure rate a given distance is known.
Geiger-Muller - ANSWER-Gas-Filled (noble gases)
High Voltage
Secondary Ionization ---> Townsend Avalanche = high sensitivity
Sinogram - ANSWER-A 2D projection space representation of a transaxial image
X-axis sinogram - ANSWER-Represents shift on LOR from the center of the gantry
Y-axis sinogram - ANSWER-Represents projection angle of LOR
Ring Artifact - ANSWER-CT artifact caused by a faulty detector
Produces ring or concentric circles on CT image
Photoelectric Effect - ANSWER-Electrons are emitted from matter
Absorption of energy from electromagnetic radiation of a very short wavelength
Filament - ANSWER-Structure on Cathode of Xray tube where electron beam is
released
, Electron Capture - ANSWER-Unstable to Stable atoms
Inner shell e- to nucleus
combines w/proton
creates neutron and neutrino
neutrino ejected
Bremsstrahlung - ANSWER-Braking Radiation
Radiation emitted when electrons are decelerated or braked
80-90% of all xrays
Beta Particle - ANSWER-High speed particle identical to an electron, emitted from
nucleus
Average variance - ANSWER-Square sum of the differences of the relative crystal
efficiencies between two scans
ex: daily blank sino vs reference blank sino
Alpha Particle - ANSWER-Emitted from nucleus
2 protons and 2 neutrons
Helium Atom
24.8 mSv
PET w/ 10 mCi = 7 mSv
Diagnostic CT w/ Contrast = 17.6 mSv
Topogram = .2 mSv - ANSWER-Radiation Dose of Diagnostic PET/CT
8.5 mSv
Pet w/ 10 mCi = 7 mSv
Low-Dose CT = 1.3 mSv
Topogram = 0.2 mSv - ANSWER-Radiation Dose of Normal PET/CT
Young's Formula for PED dose - ANSWER-[Age/(Age + 12)] x Adult Dose
Webster's PED Dose - ANSWER-[(age+1)/(age+7] x Adult Dose
Clark's PED Dose - ANSWER-(weight/150 lb.) x Adult Dose
CPM/DPM x 100 - ANSWER-Well Counter Effieciency
Synthesis Modules - ANSWER-Automated systems inside of lead-shielded hot cells
Nucleophillic Subustitution - ANSWER-Electron-rich group of atoms changes place on a
molecule w/ a positively charged "leaving group" of atoms