CT Boards Flashcards
(129 cards)
1
Q
Informed consent is not required for any invasive procedure.
A
False
2
Q
Normal body temperature is…
A
97.7 to 99.5 degrees F (36.5 to 37.5 degrees C)
3
Q
Normal pulse rate for adults is…
A
60 to 100 beats per minute
4
Q
Normal pulse rate for children is…
A
70 to 120 beats per minute
5
Q
What is systolic blood pressure?
A
Pressure within arteries during cardiac contraction - - should be less than 120 mmHg
6
Q
What is diastolic blood pressure?
A
Pressure within arteries during relaxation of the heart - - should be less than 80 mmHg
7
Q
Normal blood oxygen levels are…
A
95% to 100%
8
Q
What does the cardiac cycle refer to?
A
The series of blood flow related events that occur from the beginning of one heart beat to that of the next
9
Q
What are the 3 distinct stages of the cardiac cycle?
A
- Atrial systole
- Ventricular systole
- Complete cardiac diastole
10
Q
What is Atrial Systole?
A
Contraction of left & right atria - - corresponds to the onset of the P wave of an ECG
11
Q
What is Ventricular Systole?
A
Contraction of left & right ventricles - - corresponds to the beginning of the QRS complex of an ECG
12
Q
What is Complete Cardiac Diastole?
A
Period of relaxation after heart contraction - - consists of ventricular & atrial diastole - - corresponds to the T wave of an ECG
13
Q
When are Cardiac CT images typically acquireed and reconstructed?
A
During the diastolic phase
14
Q
Why do slower heart rates yield higher quality cardiac CT images?
A
Slower heart rates exhibit longer diastolic phases
15
Q
Normal BUN value ranges in adults is…
A
7 to 25 mg/dL
16
Q
Normal Creatinine levels in adults is…
A
0.5 to 1.5 mg/dL
17
Q
What is the most accurate measure of renal function?
A
Glomerular Filtration Rate (GFR)
18
Q
How is GFR calculated?
A
Taking the patient’s measured serum creatinine level and factoring in the patient’s age, sex, & race.
19
Q
Normal range of GFR for men is…
A
70 +/- 14 mL/min/m2
20
Q
Normal range of GFR for women is…
A
60 +/- 10 mL/min/m2
21
Q
What is Prothrombin TIme (PT)?
A
A measure of blood coagulation
22
Q
Normal range of Prothrombin Time (PT) is…
A
12 to 15 sec
23
Q
Normal range of Partial Thromboplastin Time (PTT) is…
A
25 to 35 sec
24
Q
What is D-dimer testing used to diagnose?
A
A deep vein thrombosis (DVT) & Pulmonary Embolism
25
What size IV catheter should be used for flow rates exceeding 3 mL/sec?
20 gauge or larger
26
How do you care for an extravasation?
Remove the needle/catheter & apply pressure with a warm, moist compress
27
Name examples of ionic contrast media...
- Iothalamate meglumine (Conray)
| - Diatrizoate sodium (Hypaque)
28
Name examples of non-ionic contrast media...
- Iohexol (Omnipaque)
- Iopamidol (Isovue)
- Ioversol (Optiray)
- Iodixanol (Visipaque)
29
What is the routine transit time for barium sulfate through the GI tract?
30 to 90 min
30
What is the routine transit time for water-soluble iodinated contract agents through the GI tract?
30 to 90 min
31
What type of contrast media is used for enterography & why?
Neutral oral contrast media distends the GI tract while still allowing for clear visualization of the bowel wall
32
List the mild reactions to iodinated contrast media...
- Nausea/Vomiting
- Mild urticaria (hives)
- Pronounced sensation of warmth and/or flushing
- Altered taste
- Sweats/chills
- Nasal stuffiness/sneezing
- Anxiety
33
List the moderate reactions to iodinated contrast media...
- Mild bronchospasm
- Moderate to severe urticaria
- Vasovagal response
- Tachycardia from hypotension
34
List the severe reactions to iodinated contrast media...
- Profound hypotension
- Laryngeal edema
- Severe bronchospasm
- Pulmonary edema
- Cardiac arrythmia
- Seizures
- Cardiopulmonary arrest
- Death
35
What is inherent absorption efficiency?
The ability of the detector to capture transmitted x-ray quanta & produce the appropriate response
36
What is geometric efficiency of a detector array?
The spatial arrangement of detector elements, including the amount of interspace material required between adjacent elements
37
What is protocol optimization?
The process of adjusting parameters such as mA/kVp, slice thickness, & pitch for the purpose of reducing patient radiation dose while maintaining adequate image quality
38
There is a (directly/indirectly) proportional relationship between the mA setting, scan time, & patient radiation dose.
Directly
39
What is dose profile?
The section of the patient that is exposed to radiation during CT data acquisition.
40
When collimation is increased (ex: thinner slices), what happens to image noise?
More noise is yielded.
41
When dose is decreased what happens to image noise?
More noise is yielded.
42
Image noise is (directly/indirectly) related to patient size...
Directly
43
What happens to radiation dose saving as the heart rate increases?
It decrease - - dose increases
44
What is CT dose index (CTDI)?
An appropriate measure of the dose received in a single CT section or slice.
45
What is Multiple scan average dose (MSAD)?
A calculation of the average cumulative dose to each slice within the center of the a scan consisting of multiple slices.
46
What is pitch?
The amount of table travel per tube rotation divided by the collimation.
47
Window Level value of Gray/White Matter
35
48
Window Width value of Gray/White Matter
100
49
Window Level value of Bone (Head Work)
400
50
Window Width value of Bone (Head Work)
3000
51
Window Level value of a hemorrhage/hematoma
75
52
Window Width value of a hemorrhage/hematoma
150
53
Window Level value of an acute ischemia
35
54
Window Width value of an acute ischemia
25
55
Slice thickness of axial images for CT Head
2-5 mm from base of skull through the posterior fossa
| 5-10 mm from posterior fossa through the vertex
56
Window Level value of soft tissue (Head Work)
40
57
Window Width value of soft tissue (Head Work)
400
58
Window Level value of Soft Tissue (Neck to Chest)
50
59
Window Width value of Soft Tissue (Neck to Chest)
400
60
Window Level value of bone (Neck to Chest)
300
61
Window Width value of bone (Neck to Chest)
2000
62
Window Level value of Lung Parenchyma
-450
63
Window Width value of Lung Parenchyma
1400
64
Window Level value of Mediastinum
40
65
Window Width value of Mediastinum
350
66
Window Level value of soft tissue (abdomen)
40
67
Window Width value of soft tissue (abdomen)
350
68
Window Level value of soft tissue (spine)
50
69
Window Width value of soft tissue (spine)
400
70
Window Level value of bone (spine)
300
71
Window Width value of bone (spine)
2000
72
Slice thickness of axial images for CT Temporal Bones & IACs
1-2 mm
73
Slice thickness of coronal images for CT Temporal Bones & IACs
1-2 mm
74
Slice thickness of axial images for CT Orbits
1-3 mm acquired parallel to the IOML
75
Slice thickness of coronal images for CT Orbits
1-3 mm acquired perpendicular to the axial plane
76
Slice thickness of axial images for CT Facial Bones/Sinuses
1-3 mm
77
Slice thickness of coronal images for CT Facial Bones/Sinuses
1-3 mm
78
List the Components of the Circle of Willis
- Right & Left Anterior Cerebral Arteries
- Anterior Communicating Artery
- Right & Left Internal Carotid Arteries
- Right & Left Posterior Cerebral Arteries
- Right & Left Posterior Communication Arteries
79
Slice thickness of axial images for CTA Brain
0.5-1.5 mm
80
What is the delay for a CTA Brain?
12-20 sec
81
What is the delay for a CT Head/Facial Bones/Orbits/Sinuses?
60 sec
82
Slice thickness of axial images for CT Soft Tissue Neck
3-5 mm
83
Slice thickness of axial images of CT Larynx
0.5-2 mm
84
What is the delay for a CT Soft Tissue Neck?
30-60 sec
85
Slice thickness of axial images for CTA Carotid
0.5-1.5 mm
86
What is the delay for a CTA Carotid?
15-18 sec
87
Slice thickness of axial images for a HRCT of chest
1-2 mm
88
What is Cerebral Perfusion?
The level of blood flow throughout brain tissue
89
Slice thinkness of axial images for a CTA Chest...
0.5 - 1.25 mm
90
How does a saline flush in CTA work improve image quality?
It reduces artifact from dense contrast agent in the SVC
91
What is the delay for a CTA Chest?
20-25 sec
92
A CAC Score of 1-10 indicates what level?
Minimal
93
A CAC Score of 11-100 indicates what level?
Mild
94
A CAC Score of 101-400 indicates what level?
Moderate
95
A CAC Score of > 400 indicates what level?
Extensive
96
What is scanned for a CTA Coronary?
Aortic Arch through Cardiac Base
97
What mediation dilates the blood vessels for a CTA Coronary?
Nitroglycerin
98
What medication controls the heart rate for a CTA Coronary?
B-Blockers
99
Name the two coronary arteries.
Right Coronary Artery (RCA) & Left Coronary Artery (LCA)
100
Where do the coronary arteries arise from?
The aorta
101
Name the branches of the RCA in proximal to distal order.
- Conus Artery
- Sinus Nose Artery
- Right Atrial Branches
- Right Ventricular Branches
- Posterior Descending Artery (PDA)
- Posterior Left Ventricular Branches (PLBs)
102
Name the branches of the LCA.
- Left Anterior Descending Artery (LAD)
| - Left Circumflex Artery (LCX)
103
What does the LAD branch into?
- Left Ventricular
- Right Ventricular
- Interventricular Diagonal Branches
104
What does the LCX branch into?
Obtuse Marginal Arteries to the Left Ventrical & Left Posterolateral Branches
105
85% of the population is (Right/Left) Dominant.
Right
106
Where does the PDA branch from on a Right Dominant Heart?
RCA
107
8% of the population is (Right/Left) Dominant.
Left
108
Where does the PDA branch from on a Left Dominant Heart?
LCX
109
What is temporal resolution?
The ability of a MDCT system to freese the motion of the heart as well as the atrial motion velocity within the coronary vasculature.
110
Where is a Stanford type A dissection?
Ascending Aorta
111
Where is a Stanford type B dissection?
Descending Aorta
112
Why is non-contrast images of the liver ordered?
- Hepatic Calcifications
- Fatty infiltration
- Hemorrhage
113
What is the HU range for normal, unenhanced hepatic parenchyma?
45-65 HU
114
Hepatic neoplasm metastases usually appear (hyper/hypo)-dense.
Hypodense
115
What are examples of hypervascular tumors?
- Hemangiomas
- Hepatocellular Carcinomas (HCC)
- Focal Nodular Hyperplasia (FNH)
- Hepatic Cysts
116
Name some malignant neoplasms of the liver.
- Hepatocellular Carcinoma
| - Metastases
117
Name the two vessels that supply the liver.
Portal vein & Hepatic Artery
118
Name the three phases of hepatic contrast enhancement.
- Arterial Phase
- Portal/hepatic venous phase
- Equilibrium Phase
119
What is peak enhancement of contrast media during an Arterial Phase?
25-35 sec after initiation of contrast media
120
When is peak enhancement of contrast media during a Venous Phase?
60-70 sec after initiation of contrast media
121
When is the equilibrium phase of a liver?
2-3 min after initiation of contrast media
122
What is the HU range for normal unenhanced spleen?
40-60 HU
123
What is a Whipple Procedure?
A resection of the pancreas & duodenum
124
What is the HU range for the adrenal glands?
25-40 HU
125
What is the HU range for muscle?
25-40 HU
126
What is the HU range of a simple cyst on a kidney?
127
What is the HU range of a hyperdense cyst on a kidney?
25-90 HU on an unenhanced scan
128
What is the HU range of an angiomyolipoma?
129
What is the HU range of Renal Cell Carcinoma (RCC)?
> 20-25 HU with contrast enhancement
