Unit 1 Flashcards
(149 cards)
1
Q
Higher atomic number means….
A
More x-ray absorption
2
Q
Calcium (bone) has a high or low atomic number?
A
High
3
Q
Soft tissue has a high or low atomic number?
A
Low (more matter more scatter)
4
Q
What is Contrast Media?
A
Contrast media are diagnostic agents that are instilled into the body orifices or injected into the vascular system, joints, and ducts to enhance subject contrast in anatomic areas where low subject contrast exists
5
Q
State the purpose of contrast media
A
The purpose is to provide a more significant distinction between adjacent anatomical structures
or in other words (from the book)….
anatomic detail to be visualized, its ability to distinguish between radiographic densities enables differences in anatomic tissues to be visualized.
6
Q
What factors affect the degree of radiographic density differences?
A
- Absorption characteristics of the tissues that comprise the anatomic part
- Technical factors used
- Characteristics of the image receptor
- Automatic image processing
- The use of contrast media agents
7
Q
What is the term:
Atomic Numbers
A
Numbers of photons in the nuclei of the different elements
8
Q
What is the term:
Bronchospasm
A
Involuntary constriction of the bronchial tubes usually resulting from an immune system reaction to a foreign particle or molecule
9
Q
What is the term:
Contraindications
A
Factors of a patient’s history or present status that indicate that a medical procedure should not be performed or that a medication should not be given
10
Q
What is the term:
Creatinine
A
Nitrogen-containing waste products of metabolism excreted by the kidneys filtration system; high blood plasma levels indicate poor filtration by the kidney
11
Q
What is the term:
Extravasation
A
Leakage from a vessel into the tissue
12
Q
What is the term:
Flocculation
A
Formation of flaky masses resulting from precipitation or coming out of a suspension or solution
13
Q
What is the term:
Osmolality
A
Measurement of the number of particles (molecules or ions or cations) that can crowd out water molecules in a measured mass (kilogram) of water
14
Q
What is the term:
Osmosis
A
Movement of water from an area of high concentration to an area of low concentration through a semipermeable membrane such as blood vessel walls and cell membrane
15
Q
What is the term:
Shock
A
Inadequate blood flow within the body with resulting loss of oxygen and therefore energy
16
Q
What is the term:
Solution
A
Uniform mixture of two or more substances composed of molecule-sized particles that do not react together chemically
17
Q
What is the term:
Suspension
A
Nonuniform mixture of two or more substances, one of which is composed of larger than molecule size particles that have a tendency to cluster together
18
Q
Contrast media are generally classified as….
A
negative or positive contrast agents
19
Q
Negative Contrast Agent
A
Allows x-ray photons to penetrate the medium easily
Ex: air (gas)
20
Q
Positive Contrast Agent
A
Will absorb most (more) of the x-ray photons leading to a radiopaque appearance on the produced images
21
Q
What are 3 types of contrast agents?
A
Radiolucent (negative), Radiopaque (positive), & Specialty Contrast Agents (US & MRI)
22
Q
Radiolucent (negative) contrast media
A
X-ray photons are easily transmitted or scattered through radiolucent contrast media. These media are relatively lucent to x-rays. The anatomic areas filled by these agents appear dark (increased density) on radiographs. These media care composed of elements with low atomic numbers.
23
Q
Radiopaque (positive) contrast media
A
X-ray photons are absorbed by radiopaque contrast media because these media are opaque to x-rays. The anatomic areas filled by these agents appear light (decreased density) on radiographs. These media are composed of elements with high atomic numbers
24
Q
What are the five radiographic densities?
A
- Air (gas)
- Fat
- Water
- Mineral (contrast)
- Metal (Markers)
25
What is the _difference_ between _negative_ and _positive_ contrast material?
Negative contrast is composed of low atomic number elements which appears radiolucent on an image, whereas positive contrast is composed of higher atomic number elements which appears radiopaque on an image (absorbs more radiation)
26
What are some specialty contrast agents?
Ultrasound (soundwaves - microbubbles)
&
MR scanning (uses magnetic energy - gadolinium & NSF: nephrogenic systemic fibrosis)
27
What is optimal contrast material?
* Very-high contrast visualization (makes it easy to visualize)
* Extremely low toxicity to patient
* Persistence in patient anatomy until imaging is completed
* Low cost
* Minimal or no side effects
* No residual effects within patient
28
What are key contrast characteristics?
* Ability of agent to mix with body fluids (uniform appearance)
* Viscosity
* Ionic Strength (want to avoid)
* Persistence in the body
* Iodine content
* Osmolality (Vital)
* Potential for toxicity (could be toxic)
29
What are some radiographic contrast media choices?
*(Primary)*
* _Barium_
* Atomic number 56
* _Iodine_
* Atomic number 53
The higher atomic number = more radiation = more white on the image
(Other choices that are not as common)
* Air/gas
* Average atomic number 8
* Carbon Dioxide
* Room air
Lower atomic number = absorbs less radiation = more darker on the image
30
Barium studies of the GI tract can use what two types of contrast?
Single contrast (contrast only)
OR
Double contrast (barium + air)
31
Is barium sulfate water soluble _or_ not water soluble?
Barium sulfate is not water soluble!
32
What factors should you consider when giving contrast (barium) to a patient?
* Age (ability to communicate/follow directions + increase risk for colon perforation cause by loss of tissue tone)
* Diverticulitis or Ulcerative Colitis (increase difficulty holding enema + increase risk for colon perforation)
* Long-term steroid therapy (increase risk for colon perforation)
* Colon biopsy within previous 2 weeks (Lower gastrointestinal series contraindicated)
* Pregnancy (inform before proceeding)
* Mental retardation, confusion, or dizziness (increase risk for aspiration during upper gastrointestinal series)
* Recent onset of constipation or diarrhea (increase risk for colon perforation or tumor rupture)
* Nausea & vomiting (increase risk for aspiration during upper gastrointestinal series)
33
What are 5 important things to know about contrast media?
1. Human tissues inherently have low subject contrast (visualize anatomy normally not seen)
2. Takes advantage of the photoelectric effect and high-atomic number elements
3. Requires the administration of media into patient (contrast is classified as a drug)
4. Requires attention to indications and contraindications (when is it safe to use contrast considering a patient's medical history)
5. Warrants serious attention to patient reaction
34
What is the term:
Compound
Substance composed of two or more elements combined in definite ratios that give the substance specific properties
35
What is the term:
Ionic
Atom or molecule having a negative charge (anion) or positive charge (cation)
36
What are 2 important things to know about ionic contrast agents?
1. Uses iodine as the contrast molecule (iodine atomic number of 53 - excellent positive contrast agent) (tri-iodinated)
2. Dissociates into two ions: Anion (-) & Cation (+)
37
Ionic contrast agents dissociates into what two ions?
Anion ( - )
Cation ( + )
38
What does anion and cation eventually do regarding contrast?
Eventually joins with carbon atoms or a combination of atoms (these combinations affect how the body excretes the contrast and the osmotic effects of the contrast)
39
What does anion do regarding contrast?
Joins other carbon atoms to form a 3 ionized atom termed tri-ionated
40
What are 5 important things to know about osmolality?
1. The measure of the total number of particles in solution per kilogram of water.
2. _Great biological significance._
3. Most adverse reactions to contrast result from the osmolality of the agent (dangerous to utilize) (increase number of particles).
4. Nonionic contrast agents are typically LOCM and do not contain ions (primary contrast agent used today).
5. _High_ osmotic contrast has an increase number of particles in the solution such as blood plasma. The particle pulls water towards them which affect the osmotic pressure within the body.
41
What are 3 important things to know about nonionic contrast agents?
1. Too big to have a osmotic effect on the body giving these types of contrast the designation of lower osmolality contrast media.
2. _Does not break down into anions or cations_ but _can be dissolved by water_ (even with the larger molecules making it safer to inject into the bloodstream) the body can filter and discrete the contrast.
3. Water soluble
42
What are the advantages of nonionic, LOCM?
* Nonionic contrast is safer because it has a **_lower osmolality_** pressure therefore does not draw water into the molecular components like ionic contrast.
* Nonionic breakdown and less toxic at cellular level (does less damage to the body than ionic contrast)
* Warmed to increase viscosity, although this is not typically used anymore but the contrast can be thick which is why they warm it to reduce thickness.
* Less likely to cause patient reaction
* More tolerable by patients
* High contrast effect resulting from number of iodine atoms per molecule.
43
What is the term:
Blood Urea Nitrogen (BUN)
BUN test can reveal whether the urea nitrogen levels are higher than normal, suggesting that the kidneys or liver may not be working properly
44
What are some general effects of water soluble ionic contrast agents?
* Most contrast reactions occur relating to osmolality
* Dehydrated patients are vulnerable to hypovolemic shock (could be critical for the patient)
* Greater the number of particles in a contrast agent, the more molecules there are to pull water from the patient
* Expressed as milliosmoles per kilogram of water at 37 degrees C
45
What are some considerations to think about when giving contrast?
* Patient history - allergies, asthma, diabetes, diseases or general health problems.
* Renal function (most important) kidneys are responsible for filtering out the contrast agent and removing it from bloodstream.
* BUN (if kidneys are not functioning, contrast can damage them)
* Creatinine also a waste product of metabolism.
* Metformin (glucophage) should be discontinued for 48 hours before and 48 hours after the use of iodine contrast media.
(contrast enhanced CT studies)
46
What are some anaphylactoid reactions?
* Urticaria (hives)
* Wheezing
* Throat swelling (edema)
* Bronchospasm (involuntary constriction of the bronchial tubes)
* Nausea
* Vomiting
* Cardiac arrest
47
Contrast Reactions
* Generally occur within the first (5) minute(s) of injection
* Can be unpredictable
* Mild reaction may worsen to severe at any time
* Reaction is different from a side effect
Monitor patient continually!
48
MILD REACTION - signs and symptoms
Nausea
Vomiting
Cough
Warm Feeling
Headache
Dizziness
Shaking
Itching
Strange taste in mouth
Pallor (patient color)
Flushing chills
Sweats
Urticaria (hives)
Nasal stuffiness
Swelling about the eyes and face
Anxiety (nervousness)
49
MODERATE REACTION - signs and symptoms
Tachycardia
Bradycardia
Hypertension
Pronounced cutaneous reaction
Hypotension
Dyspnea
Bronchospasm
Wheezing
Laryngeal Edema
50
SEVERE REACTION - signs and symptoms
Laryngeal edema
Convulsions
Profound Hypotension
Cardiac arrhythmias
Unresponsiveness
Cardiac arrest
51
What are some health professional responsibilities when administering contrast agents?
* Administered under the supervision of a licensed physician with proper qualifications.
* Patient assessment and history
* Patient comfort and education
* Recognize signs and symptoms of reaction and act appropriately
* Patient care and surveillance
* Post exam considerations for patient
* Remain calm and reassuring during procedures
52
What are the routine projections for sacrum and coccyx?
AP or PA Axial Sacrum
Lateral Sacrum
AP or PA Axial Coccyx
Lateral Coccyx
53
How many segments does the coccyx have?
Why isn't there specific number of segments?
Consists of 3-5 segments
There isn't a specific number of segments because each person is different so one person might have 3 segments and other could have 4 or 5 segments, depends on how they were born.
54
What angle should the coccyx have for an AP Axial projection?
10 degrees Caudal
55
What angle should the sacrum have for an AP Axial projection?
15 degree Cephalic
56
What angle should the coccyx have for an PA Axial projection?
10 degrees Cephalic
57
What angle should the sacrum have for an PA Axial projection?
15 degrees Caudal
58
Name the anatomy that is circled in green on the coccyx
* Base
* Apex
59
Describe the patient position for a AP or PA Sacrum Axial Projection
The patient is positioned supine for the AP Axial projection and prone for the PA Axial projection. The patient should be adjusted so both ASIS are equal distance from the IR
60
(**AP** Axial projection of the _sacrum_)
The _vertical_ cross hair of the CR is centered to….
MSP
| (Midsagittal Plane)
61
(**AP** Axial projection of the _sacrum_)
The _horizontal_ cross hair of the CR is centered…
2 inches superior to the pubic symphysis
62
(**PA** Axial projection of the _sacrum_)
The _vertical_ cross hair of the CR is centered to….
MSP
| (Midsagittal Plane)
63
(**PA** Axial projection of the _sacrum_)
The _horizontal_ cross hair of the CR is centered…
to the clearly visible sacral curve
64
What is the patient position on the table for a AP or PA Axial Projection?
Prone or supine with the lower limbs extended
65
Can you shield on an AP or PA Axial projection of the sacrum?
Shielding _can_ be applied to **MALE** patients ONLY
66
What is the patient position for a AP or PA Axial projection of the Coccyx?
Prone or supine on the table
67
Can you shield on an AP or PA Axial projection of the coccyx?
Shielding _can_ be applied to **MALE** patients ONLY
68
Describe the patient position for an AP or PA Axial Projection of the coccyx?
The patient is positioned supine for the AP Axial projection and prone for the PA Axial projection. The patient should be adjusted to both ASIS are equal distance to the IR
69
(**AP** Axial projection of the coccyx)
The _vertical_ cross hair of the CR is centered…
MSP
| (Midsagittal plane)
70
(**AP** Axial projection for the coccyx)
The _horizontal_ cross hair of the CR is centered…
2 inches superior to pubis symphysis
71
(**PA** Axial projection of the _coccyx_)
The _vertical_ cross hair of the CR is centered…
MSP
| (Midsagittal Plane)
72
(**PA** Axial projection of the _coccyx_)
The _horizontal_ cross hair of the CR is centered…
to the easily palpable coccyx
73
What is the patient position for a LAT sacrum and coccyx?
Recumbent in either the right or left lateral position
74
Can you shield on a LAT sacrum/coccyx?
shielding _can_ be applied on **MALE** patients ONLY
75
Describe the patient position for a LAT sacrum/coccyx
The patient is positioned recumbent in a lateral position on either the right or left side.
The arms should be flexed and positioned at a right angle. The shoulders and pelvis should be in a true lateral position.
The patient's knees should be flexed, and a sponge placed between the knees for comfort if needed.
Place a support under the patient to place the long axis of the spine horizontal to the IR. Adjust the interiliac plane perpendicular to the IR.
76
How is the central ray directed for a LAT sacrum/coccyx projection?
CR is directed perpendicular to the IR
77
(LAT _sacrum_ projection)
The _vertical_ cross hair of the CR is centered…
3.5 inches posterior from the elevated ASIS
78
(LAT _sacrum_ projection)
The _horizontal_ cross hair of the CR is centered…
at the level of ASIS
79
(LAT _coccyx_ projection)
The _vertical_ cross hair of the CR is centered…
3.5 inches from the elevated ASIS
80
(LAT _coccyx_ projection)
The _horizontal_ cross hair of the CR is centered…
2 inches inferior to ASIS
81
What are the routine projections for sacroiliac joints (SI joints)?
AP or PA Obliques
82
What is the patient position for the sacroiliac joint AP Oblique projection?
Is either RPO or LPO
RPO = Right Posterior Oblique Position or LPO = Left Posterior Oblique Position
83
Can you shield on a AP Oblique sacroiliac joint projection?
Shielding _can_ be applied to **MALE** patients ONLY
84
Describe the patient position on a AP Oblique sacroiliac joint projection
The patient is positioned **supine** with the **side of interest elevated** (up off of the table/IR) **25 to 30 degrees**. In this position the side being imaged is _further (away) from the IR._
85
How is the central ray directed for a AP Oblique sacroiliac joint projection projection?
CR is directed perpendicular towards the IR
86
(AP Oblique sacroiliac joint projection)
The _vertical_ cross hair of the CR is centered…
1 inch medial from the elevated ASIS
87
(AP Oblique sacroiliac joint projection)
The _horizontal_ cross hair of the CR is centered…
to the level of ASIS
88
What is the patient position for a PA Oblique sacroiliac joint projection?
Patient is either RAO or LAO
**RAO** = Right Anterior Oblique Position or **LAO** = Left Anterior Oblique Position
89
Can you shield on a PA Oblique sacroiliac joint projection?
Shielding _can_ be applied to **MALE** patients ONLY
90
_Describe_ the patient position for a PA Oblique sacroiliac joint projection
The patient is positioned prone with the patient rotated 25 to 30 degrees. In this position the side being imaged is closest to the IR.
The patient should flex the forearm and knee to help support the required rotation for this position.
91
How is the central ray directed for a **PA** Oblique sacroiliac joint projection projection?
CR is directed perpendicular toward the IR
92
(PA Oblique sacroiliac joint projection)
The _vertical_ cross hair of the CR is centered…
1 inch medial from the ASIS closest to the IR
93
(PA Oblique sacroiliac joint projection)
The _horizontal_ cross hair of the CR is centered…
to the level of ASIS
94
What is the sacrum formed/fused by?
5 sacral vertebral segments into a curved triangular bone
95
The sacrum is wedged between what bones?
Between the iliac bones of the pelvis, with its broad base directed obliquely, superiorly, and anteriorly and its apex directed posteriorly and inferiorly
96
How does the sacrum bone normally look?
Normally longer, narrower, more evenly curved, and more vertical in position in males than in females
(Although the size and degree of curvature of the sacrum vary in different patients)
97
What does the female sacrum look like and how is it placed?
The female sacrum is more acutely curved, with its greatest curvature in the lower half of the bone;
it also lies in a more oblique plane, which results in a sharper angle at the junction of the lumbar and pelvic curves
98
The superior portion of the first sacral segment remains distinct and resembles the vertebrae of what region?
Lumbar
99
The superior surface of the base of the sacrum corresponds in size and shape to the inferior surface of what lumbar segment?
What does its articulation help form?
It corresponds to the last lumbar segment, with which it articulates to form the lumbosacral junction
100
The concavities on the upper surface of the pedicles of the first sacral segment and the corresponding concavities on the lower surface of the pedicles of the last lumbar segment form what pair?
The last pair of intervertebral foramina
101
The superior articular processes of the first sacral segment articulate with the inferior articular processes of the last lumbar vertebra to form what pair of joints?
The last pair of zygapophyseal joints
102
What is directly behind the bodies of the sacral segments?
Sacral Canal
103
Directly behind the bodies of the sacral segments is the sacral canal, which is the continuation of what?
Continuation of the vertebral canal
104
The sacral canal is contained within what?
What does it transmit?
The sacral canal is contained within the bone and transmits the sacral nerves
105
Each anterior and posterior walls of the sacral canal is perforated by what?
What is its purpose?
Perforated by four pairs of pelvic sacral foramina.
Its purpose is for passage of the sacral nerves and blood vessels
106
What anatomy is circled in red?
Base of the sacrum
107
What anatomy is the pink arrow pointing to?
Superior Articular Process on the sacrum
108
What anatomy is the purple arrow pointing to?
The Ala on the sacrum
109
What anatomy is circled in green?
Pelvic Sacral Foramina
110
What anatomy is circled in blue?
The apex of the sacrum
111
What bone is outlined in green?
Sacrum
112
What bone is outlined in blue?
Coccyx
113
How many segments are on the coccyx in this picture?
4
114
What anatomy is circled in purple?
Body of the 1st Sacral Segment on the sacrum
115
What anatomy is circled in red?
Body of the 2nd sacral segment on the sacrum
116
What anatomy is circled in pink?
Body of the 3rd sacral segment on the sacrum
117
What anatomy is circled in orange?
Body of the 4th sacral segment on the sacrum
118
What anatomy is circled in yellow?
Body of the 5th sacral segment on the sacrum
119
How many pairs are there of the pelvic sacral foramina?
4
120
What anatomy is the red arrow pointing to?
Superior Articular Process of the sacrum
121
What anatomy is the orange arrow pointing to?
The base of the sacrum
122
What anatomy is circled in yellow?
The Sacral Promontory of the sacrum
123
What anatomy is the green arrow pointing to?
The Auricular Surface of the sacrum
124
What anatomy is the blue arrow pointing to?
The Sacral Cornu of the sacrum
125
What anatomy is the purple arrow pointing to?
Coccygeal Cornu of the coccyx
126
What anatomy is circled in red?
Superior Articular Process of the sacrum
127
What anatomy is circled in green?
The sacral canal on the sacrum
128
What anatomy is circled in purple?
The Ala of the sacrum
129
What anatomy is circled in blue?
The body of the first segment of the sacrum
130
Where are the intervertebral discs located?
One disc between each vertebra
131
What is the function of the intervertebral discs?
As shock absorbers and also keeps the vertebra separated
132
Intervertebral discs consist of 2 layers which are called…
Annulus Fibrosus
(made of fibrocartilage)
&
Nucleus Pulposus
(made of loose fibers in a mucoprotein gel)
133
What are the routine projections for the thoracic spine?
AP
Lt. Lateral
Cervicothoracic, Swimmers (Twining or Pawlow)
(Non-routine: Oblique)
134
What is scoliosis?
Abnormal lateral curvature of vertebral column
135
What are the typical studies for scoliosis?
PA upright
PA upright with lateral bending
Lateral upright
136
How many vertebrae are there in the thoracic spine?
12
137
The thoracic vertebrae has 2 primary parts to complete the vertebrae, what are they?
The body and the vertebral arch
138
For the thoracic vertebrae, is the body more posterior or anterior?
What about the arch?
Body = Anteriorly
Arch = Posteriorly
139
The thoracic vertebral arch has 6 parts that should be known. What are they?
1. Transverse process
2. Spinous process
3. Lamina
4. Pedicle
5. Superior Articular Process
6. Inferior Vertebral Notch
140
What anatomy is the purple arrow pointing to?
The body of the vertebra
141
What anatomy is outlined in black?
The pedicle
142
What anatomy is circled in orange?
Superior articular process
143
What anatomy is circled in light blue?
Transverse process
144
What anatomy is circled in yellow?
The lamina
145
What anatomy is the red arrow pointing to?
Inferior vertebral notch
146
What anatomy is the dark blue arrow pointing to?
Inferior articular process
147
What anatomy is the pink arrow pointing to?
Spinous process
148
What anatomy is circled in green?
(It is not shown very well on this image but its suppose to be there)
Hint: it is a facet but which kind and where are they located in regard to the body
Green circle on the top: **Superior costal demifacet**
Green circle on the bottom: **Inferior costal demifacet**
149
The zygapophyseal joints of the thoracic region (except the inferior articular processes of the twelfth vertebra) angle anteriorly approximately ___ to ___ degrees to form an angle of ___ to ___ degrees (open anteriorly) to the midsagittal plane of the body.
Angles anteriorly approximately **_15**_ to _**20**_ degrees to form an angle of _**70**_ to _**75_** degrees to the midsagittal plane of the body
