Patient Care In Computed Tomography

Front 1

Types of immobilization

Back 1

Cushions,Straps and breath-hold

Front 2

Patient History

Back 2

Non-leading or open-ended questions
Focused questioning for add'l information

Front 3

Normal body temp

Back 3

97.7-99.5

Front 4

Pulse Rate
1) Adult
2) Child

Back 4

1) 60-100 bpm
2) 70-120 bpm

Front 5

Systolic blood pressure is

Back 5

Arterial cardiac contraction
Less than 120 mm

Front 6

Diastolic blood pressure is

Back 6

Relaxation of heart
Less than 80 mm

Front 7

Normal respiration
1) Adult
2) Child

Back 7

1) 12-20
2) 20-30

Front 8

Pulse Oximeter measures ____, which should be between _____ and ____.

Back 8

Blood oxygen levels
95%-100%

Front 9

Cardiac cycle is

Back 9

The series of blood flow-related events that occure from the beginning of one heartbeat to the next

Front 10

Diastole refers to _____
Systole refers to _____

Back 10

Relaxation of cardiac muscle
Contraction of cardiac muscle

Front 11

Three stages of cardiac cycle

Back 11

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

Front 12

Cardiac CT images taken on

Back 12

Diastolic phase

Front 13

BPM for optimal imaging on 64 slice

Back 13

65 BPM

Front 14

BUN levels between ___ and ___

Back 14

7-25 mg/dl

Front 15

Creatinine levels between ____ and ____

Back 15

0.5-1.5 mg/dl

Front 16

BUN/Creat ratio

Back 16

6-22:1

Front 17

Glomerular filtration rate (GFR)

Back 17

70 +- 14 ml/min/m for men
60 +- 10 mL/min/m for women

Front 18

Prothromnin time is _________
and normal range is ______

Back 18

A measure of blood coagulation
12-15 secs

Front 19

International Normalized Ratio (INR) is_______ and normal range is_____

Back 19

Measure of PT after addition of tissue factor and is compared to a control sample.
0.8-1.2

Front 20

Partiak thromboplastin time (PTT) is _______ and normal range is_________

Back 20

Lab value used to detect abnormalities in bloodclotting.
25-35 secs

Front 21

Normal platelet count is

Back 21

140,000 to 440,000 per mm^3 of blood

Front 22

D-dimer testing is

Back 22

Utilized for diagnosis of DVT. Evelavted D-dimer levels may indicate recently degraded blood clots

Front 23

Coumadin is
Metformin is

Back 23

Anticoagulant AKA warfarin
Type 2 diabetic med. AKA Glucophage

Front 24

An injection of medication or contrast agent directly into blood stream is

Back 24

Type of parenteral administration

Front 25

Common injection sites

Back 25

Antecubital space
Radial aspect of wrist
Anterior forearm
Posterior hand

Front 26

IV admiinistration requires stict adherance to

Back 26

Standard precautions and aspectic technique

Front 27

Aspectic technique refers to

Back 27

Practices and procedures that a practitioner employs to reduce the risk of infection during the IV administration of contrast media

Front 28

Components of aseptic technique include:

Back 28

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

Front 29

Sterile technique refers to

Back 29

Practices and procedures used to maintain a sterile.microorganism-free enviroment during invasive CT procedures such as biopsy,aspiration, and CT arthrogram

Front 30

Sterile technique involves

Back 30

Establishing a field around the area of interest that is free of all microorganisms.

Front 31

Drip fusion

Back 31

A volume of contrast agent is administered at a slow rate over a long period.

Front 32

Bolus injection

Back 32

Iodinated contrast agent is "pushed" into the bloodstream at a rapid rate over a short period.

Front 33

Positive contrast agents (aka radiopaque contrast media)typically used for ct are

Back 33

iodine and barium

Front 34

Osmolality is

Back 34

The agents' propensity to cause fluid the outside the blood vessel(extravasular space) to move into the bloodstream (intravascular space)

Front 35

Ionic contrast media

Back 35

Are salts consisting of sodium and/or meglumine. Each molecule of ionic contrast media consists of three iodine atoms.

Front 36

When injected into the bloodstream, molecules of ionic contrast media

Back 36

Dissociate into two charged particles, or ions.

Front 37

Non-ionic contrast media are

Back 37

Non-salt chemical compunds that also contain three atoms of iodine per molecule that do not dissociate in solution.

Front 38

Routine transit time for barium sulfate through the GI tract is typically

Back 38

Between 30 and 90 minutes

Front 39

Serum iodine concentration describes

Back 39

Measure of amount of iodine within the bloodstream.

Front 40

Range of serum indine concentration for adequate opacification is

Back 40

2 to 8 mg/mL

Front 41

Intrathecal administration of iodinated contrast agent is

Back 41

The injection of the agent directly into the space surrounding the spinal cord.

Front 42

Intrathecal injections are performed during

Back 42

Ct myelography for evaluation of the spinal cord and nerve roots.

Front 43

Intra-articular administration of a contrast agent is

Back 43

The injection of the agent directly into the joint space.

Front 44

Intra-articular injections are performed during

Back 44

CT arthrography of joints, including the shoulder, wrist and knee.

Front 45

Four H's as outlined by the American College of Radiology

Back 45

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.

Front 46

Filtration within the CT x-ray tube is

Back 46

6-9 mm aL

Front 47

Inherent absorption efficiancy of each detecor element descibes

Back 47

the ability of the detector to capture transmitted x-ray quanta and produce the appropriate response.

Front 48

Geometric efficiency of a detector array descibes

Back 48

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

Front 49

Adaptive filters are

Back 49

Employed during reconstruction to reduce displayed noise within the ct image.

Front 50

Dose is higher with MSCT because

Back 50

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.

Front 51

Protocol Optimization is

Back 51

The process of adjusting parameters such as mA/kVp, slice thickness, and pitch for the purpose of reducing patient radiation dose.

Front 52

The relationship between the ma setting, scan time, and patient radiation dose is

Back 52

Directly proportional

Front 53

Dose profile is

Back 53

The section of the patient exposed to radiation . It is measured at the isocenter of the gantry.

Front 54

Increases in collimation

Back 54

Yeild images with more noise.

Front 55

Image noise is _______ to patient size

Back 55

Directly related

Front 56

Two types of Automatic tube current modulation

Back 56

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.

Front 57

Slice sensitivity profile

Back 57

Used to descibe the reconstructed CT section

Front 58

Exposure is

Back 58

The ability of xrays to ionize a volume of air. Measured in roentgens (R)

Front 59

Absorbed dose is

Back 59

The amount of x-ray energy absorbed in a unit of mass. Measured in grays (Gy)

Front 60

Kerma/Air kerma is

Back 60

Used to describe absorbed dose/amount of radiation in a quantity of air

Front 61

Effective dose accounts for

Back 61

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)

Front 62

CT dose index is

Back 62

An approximate measure of the dose recieved on a single ct section or slice

Front 63

CTDI is calculated for

Back 63

The central slice in a series that is surrounded by seven slices on each side

Front 64

CTDI is measured by

Back 64

Performing scans of both head and body sized CT phantoms using specific technical parameters. A TLD is place within each phantom during the scans

Front 65

CTDI100 is

Back 65

A fixed measurement taken with 100 mm long pencil ionization chamber and makes no reference to a specific number of splices

Front 66

CTDIw is

Back 66

An internationally accepted, wieghted dose index.

Front 67

CTDIw is calculated from

Back 67

measurements made with TLDs positioned at the center and periphery of the phantom to account in the variance in dose distribution.

Front 68

CTDIvol is

Back 68

used to approximate the radiation dose for each section obtained during a helical scan.

Front 69

CTDIvol=

Back 69

CTDIw/pitch

Front 70

As the pitch increases

Back 70

the dose per section (CTDIvol) decreases

Front 71

MSAD is a

Back 71

calculation of the average cumulative dose to each slice within the center of a scan consisting of multiple slices

Front 72

MSAD is calculated by

Back 72

(T/I) * CTDI

Front 73

During spiral or helical scanning MSAD is controlled by

Back 73

Pitch. MSAD = CTDI/pitch

Front 74

Dose length product (DLP) is

Back 74

An internationally accepted measure of CT patient dose defined as:
MSAD*slice width* no. of slices in a given volume

Front 75

Recommendations for the reduction of pediatric dose include

Back 75

1. Eliminate CT scans for inappropriate indications
2. Reduce multiphase scanning.
3. Reduce mA
4. Increase pitch

Front 76

Image Gently guildlines suggest

Back 76

1. mA and kVp should be child-size
2.One single-aquisition phase is often enough
3.Only the indicated area should be scanned.