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76 Cards in this Set
- Front
- Back
Types of immobilization
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Cushions,Straps and breath-hold
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Patient History
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Non-leading or open-ended questions
Focused questioning for add'l information |
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Normal body temp
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97.7-99.5
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Pulse Rate
1) Adult 2) Child |
1) 60-100 bpm
2) 70-120 bpm |
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Systolic blood pressure is
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Arterial cardiac contraction
Less than 120 mm |
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Diastolic blood pressure is
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Relaxation of heart
Less than 80 mm |
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Normal respiration
1) Adult 2) Child |
1) 12-20
2) 20-30 |
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Pulse Oximeter measures ____, which should be between _____ and ____.
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Blood oxygen levels
95%-100% |
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Cardiac cycle is
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The series of blood flow-related events that occure from the beginning of one heartbeat to the next
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Diastole refers to _____
Systole refers to _____ |
Relaxation of cardiac muscle
Contraction of cardiac muscle |
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Three stages of cardiac cycle
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Atrial Systole- contraction of left and right atria, corresponds to P wave of ECG
Ventricular systole-Contraction of the left and right ventricles, beginning of QRS complex on ECG Complete cardiac diastole-Period of relaxation after heart contraction, consists of ventricular and atrial diastole, corresponds to T wave on ECG |
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Cardiac CT images taken on
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Diastolic phase
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BPM for optimal imaging on 64 slice
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65 BPM
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BUN levels between ___ and ___
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7-25 mg/dl
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Creatinine levels between ____ and ____
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0.5-1.5 mg/dl
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BUN/Creat ratio
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6-22:1
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Glomerular filtration rate (GFR)
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70 +- 14 ml/min/m for men
60 +- 10 mL/min/m for women |
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Prothromnin time is _________
and normal range is ______ |
A measure of blood coagulation
12-15 secs |
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International Normalized Ratio (INR) is_______ and normal range is_____
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Measure of PT after addition of tissue factor and is compared to a control sample.
0.8-1.2 |
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Partiak thromboplastin time (PTT) is _______ and normal range is_________
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Lab value used to detect abnormalities in bloodclotting.
25-35 secs |
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Normal platelet count is
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140,000 to 440,000 per mm^3 of blood
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D-dimer testing is
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Utilized for diagnosis of DVT. Evelavted D-dimer levels may indicate recently degraded blood clots
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Coumadin is
Metformin is |
Anticoagulant AKA warfarin
Type 2 diabetic med. AKA Glucophage |
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An injection of medication or contrast agent directly into blood stream is
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Type of parenteral administration
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Common injection sites
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Antecubital space
Radial aspect of wrist Anterior forearm Posterior hand |
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IV admiinistration requires stict adherance to
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Standard precautions and aspectic technique
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Aspectic technique refers to
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Practices and procedures that a practitioner employs to reduce the risk of infection during the IV administration of contrast media
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Components of aseptic technique include:
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Thorough hand washing
Wearing of disposable gloves Cleaning of site of venipuncturein a circular mostion with an alcohol swab,moving from the center outside, application of gentle pressure wuth an alcohol swab ti the venipuncture site after removal of the needle/catheter |
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Sterile technique refers to
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Practices and procedures used to maintain a sterile.microorganism-free enviroment during invasive CT procedures such as biopsy,aspiration, and CT arthrogram
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Sterile technique involves
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Establishing a field around the area of interest that is free of all microorganisms.
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Drip fusion
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A volume of contrast agent is administered at a slow rate over a long period.
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Bolus injection
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Iodinated contrast agent is "pushed" into the bloodstream at a rapid rate over a short period.
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Positive contrast agents (aka radiopaque contrast media)typically used for ct are
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iodine and barium
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Osmolality is
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The agents' propensity to cause fluid the outside the blood vessel(extravasular space) to move into the bloodstream (intravascular space)
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Ionic contrast media
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Are salts consisting of sodium and/or meglumine. Each molecule of ionic contrast media consists of three iodine atoms.
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When injected into the bloodstream, molecules of ionic contrast media
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Dissociate into two charged particles, or ions.
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Non-ionic contrast media are
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Non-salt chemical compunds that also contain three atoms of iodine per molecule that do not dissociate in solution.
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Routine transit time for barium sulfate through the GI tract is typically
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Between 30 and 90 minutes
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Serum iodine concentration describes
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Measure of amount of iodine within the bloodstream.
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Range of serum indine concentration for adequate opacification is
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2 to 8 mg/mL
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Intrathecal administration of iodinated contrast agent is
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The injection of the agent directly into the space surrounding the spinal cord.
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Intrathecal injections are performed during
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Ct myelography for evaluation of the spinal cord and nerve roots.
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Intra-articular administration of a contrast agent is
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The injection of the agent directly into the joint space.
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Intra-articular injections are performed during
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CT arthrography of joints, including the shoulder, wrist and knee.
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Four H's as outlined by the American College of Radiology
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1. History: Thorough including allergic and contrast agent history
2. Hydration: Adequate hydration must be ensured before,during and after the exam. 3. Have equipment and expertise ready: Detailed plan to treat contrast reactions should be in place. 4. Heads up: Constant assessment of patients condition is vital. |
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Filtration within the CT x-ray tube is
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6-9 mm aL
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Inherent absorption efficiancy of each detecor element descibes
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the ability of the detector to capture transmitted x-ray quanta and produce the appropriate response.
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Geometric efficiency of a detector array descibes
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the spatial arrangement of the detector elements, including the amount of interspace material required between adjacent elements, Increased interspace materal results in a loss of geometric efficiency
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Adaptive filters are
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Employed during reconstruction to reduce displayed noise within the ct image.
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Dose is higher with MSCT because
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1. Decrease in the focal spot-detector distance
2. Use of cone beam instead of more collimaters fan beam 3. Increase in number of phases of aquisition enabled by decreased scan times 4. Use of thinner section widths for improvement of three dimentional and multiplantar reformation images. |
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Protocol Optimization is
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The process of adjusting parameters such as mA/kVp, slice thickness, and pitch for the purpose of reducing patient radiation dose.
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The relationship between the ma setting, scan time, and patient radiation dose is
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Directly proportional
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Dose profile is
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The section of the patient exposed to radiation . It is measured at the isocenter of the gantry.
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Increases in collimation
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Yeild images with more noise.
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Image noise is _______ to patient size
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Directly related
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Two types of Automatic tube current modulation
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1.Angular(x and y axis) mA setting is adjusted according to differences in thickness of the part as the tube rotates.
2.Longitudinal (z axis) Adjustment of mA setting as the scan proceeds along z axis. |
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Slice sensitivity profile
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Used to descibe the reconstructed CT section
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Exposure is
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The ability of xrays to ionize a volume of air. Measured in roentgens (R)
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Absorbed dose is
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The amount of x-ray energy absorbed in a unit of mass. Measured in grays (Gy)
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Kerma/Air kerma is
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Used to describe absorbed dose/amount of radiation in a quantity of air
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Effective dose accounts for
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The type of tisse that the radiation is deposited in. Different tissues are assigned weighting factors based on their individual radiosensitivity. Effective dose approximates the relative risk from exposure to ionizing radiation, It is measures in sieverts (Sv)
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CT dose index is
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An approximate measure of the dose recieved on a single ct section or slice
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CTDI is calculated for
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The central slice in a series that is surrounded by seven slices on each side
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CTDI is measured by
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Performing scans of both head and body sized CT phantoms using specific technical parameters. A TLD is place within each phantom during the scans
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CTDI100 is
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A fixed measurement taken with 100 mm long pencil ionization chamber and makes no reference to a specific number of splices
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CTDIw is
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An internationally accepted, wieghted dose index.
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CTDIw is calculated from
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measurements made with TLDs positioned at the center and periphery of the phantom to account in the variance in dose distribution.
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CTDIvol is
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used to approximate the radiation dose for each section obtained during a helical scan.
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CTDIvol=
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CTDIw/pitch
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As the pitch increases
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the dose per section (CTDIvol) decreases
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MSAD is a
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calculation of the average cumulative dose to each slice within the center of a scan consisting of multiple slices
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MSAD is calculated by
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(T/I) * CTDI
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During spiral or helical scanning MSAD is controlled by
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Pitch. MSAD = CTDI/pitch
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Dose length product (DLP) is
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An internationally accepted measure of CT patient dose defined as:
MSAD*slice width* no. of slices in a given volume |
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Recommendations for the reduction of pediatric dose include
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1. Eliminate CT scans for inappropriate indications
2. Reduce multiphase scanning. 3. Reduce mA 4. Increase pitch |
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Image Gently guildlines suggest
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1. mA and kVp should be child-size
2.One single-aquisition phase is often enough 3.Only the indicated area should be scanned. |