Collimator Study guides, Class notes & Summaries

Instrumentation NMTCB Practice with Certified Solutions What is a gamma camera crystal made of? Sodium iodide activated with thallium What is the purpose of the crystal in a gamma camera? To absorb gamma (γ) rays and convert them into visible-light photons What is the mechanism by which gamma (γ) rays interact with a gamma camera crystal? Photoelectric effect or Compton scattering. What is the relationship between the energy of an absorbed gamma (γ) ray and the amount of light produced by...

Radiation cannot be - Answer-seen, heard or felt Quality assurance in radiography is a - Answer-Legal requirement Recall patients who have a high caries risk should be radiographed at what intervals using horizontal bitewings? - Answer-6 months What is the purpose of black paper in intraoral film packets? - Answer-Prevents exposure of the film to light What is classed as a safe level of X-ray exposure? - Answer-There isn't a safe level What are extraoral cassettes marked with? - Answer-T...

Nuclear Medicine Final Exam corBasic Gamma Camera Components -ANSWER Collimator, NaI scintillation crystal, light guide, PMT array How does the collimator work? -ANSWER Controls which gamma rays are accepted by absorptive collimation, forming a projected image of the distribution on the surface of the crystal. What information do event signals contain? -ANSWER Position and energy information (could also contain time information). Reflective Material Around Crystal -ANSWER Maximizes ligh...

The boxlike device attached under the tube housing that allows the limited operator to vary the size of the radiation field is called a: A. collimator B. transformer C. detent D. tube port - Answer A. collimator

In order for an x-ray photon to be measured it must: 1. enter the detector chamber 2. be absorbed by the detector material 3. be converted to a measurable event CORRECT ANSWER 1,2,3 Which system component converts the projection attenuation data into the proper digital form for the array processor? CORRECT ANSWER analog-to-digital converter Which of the following is NOT a function of a PACS system? a. reconstruction of the image from the raw data b. long term data storage c. digital ...

DANB RHS Practice Test Questions with Correct Answers The size and shape of the primary beam is controlled primarily on the? a)length of PID b)collimator c)thickness of filter d)size of focal spot - Answer-b) collimator The dentist suspects that the patient has significant bone loss. The best film for reading his or her bone level is? a) parallel technique periapical b)horizontal bitewing c)panoramic film d)vertical bitewing - Answer-D) Vertical bitewing Which of the following i...

Nuclear Medicine Exam Questions with 100% Correct Answers In imaging with 67Ga-citrate, target-to-background ratio increases over time because of gallium concentration in tissue: remaining the same while blood clearance progresses decreasing while blood clearance progresses remaining the same while blood clearance decreases decreasing while blood clearance decreases - answerremaining the same while blood clearance progresses Following the injection of 67Ga-citrate, imaging can begin: i...

Gantry Contains the x-ray tube and detectors Includes 80-90-cm aperture for patient Section The same as "slice" or "cut" xray tube source of xrays reference detector used to monitor the incident beam power Collimator Restricts the size and shape of the x-ray beam

Basic Gamma Camera Components - correct answer Collimator, NaI scintillation crystal, light guide, PMT array How does the collimator work? - correct answer Controls which gamma rays are accepted by absorptive collimation, forming a projected image of the distribution on the surface of the crystal. What information do event signals contain? - correct answer Position and energy information (could also contain time information). Reflective Material Around Crystal - correct answer M...

In order for an x-ray photon to be measured it must: 1. enter the detector chamber 2. be absorbed by the detector material 3. be converted to a measurable event correct answers 1,2,3 Which system component converts the projection attenuation data into the proper digital form for the array processor? correct answers analog-to-digital converter Which of the following is NOT a function of a PACS system? a. reconstruction of the image from the raw data b. long term data storage c. digita...