Interpretation Of Lab Flashcards
What should you do first when you are looking at a scan for a patient?
Verify Name on Study is Pt Name
Verify Time/Date of Study
Verify if you have Correct Study/X-Ray
When doing X-rays, how many views do you want?
Plain and orthogonal view (90 degrees other image)
What are five relevant objects we will see on x-ray, from least dense to most dense?
Air (black) Fat Soft tissue Bone Metal (very bright)
What type of X-ray do we want for a chest view?
More than likely a PA view
-AP distorts heart field
What is order to look at X-ray?
Airway
Bones (any fractures)
Cardiac (enlarged or normal size?)
Diaphragm (any fluid build up?)
When is chest X-ray indicated for use?
It is one of more commonly ordered
-excellent to evaluate lungs, which appear black
Most abnormalities will appear gray
Is an X-ray indicated for use for the abdomen?
It’s more hard to see organs, can really only see them if surraounded by fat
However, can see calcification and metal on radiograph
What does it mean when intestines abnormally dilated?
Probably a bowel obstruction
Are kidney stones easily seen on x-ray?
Yes, are a bright, dense Foci
What is most common use for radiograph?
BONES
-x-rays are great for bone path
Outer cortex is more dense than inner, so any disruptions are easily seen
Units for CT
Hounds field Units (HU)=absorption value of x-ray beam assigned to tissue
Air=-800HU
Fat=-70HU
Water=0HU
Bone=+800HU
CT Angiography
CT Scan w IV Contrast
Similar to conventional but:
- less invasive
- similar use of radiation and IV contrast
Cons of CT angiography
Needs faster scanner and faster IV injection rate (means larger needle)
When is MRI used?
Soft Tissue
-ligamentous, meniscal, muscle
T1 vs T2 MRI
Water is black on T1, but in T2 water is (t)TOO BRIGHT
Advantages of MRI
Greater diff of soft tissues
Can be acquired in any plan
Can study w/o contrast
Cons of MRI
Longer wait time
Very sensitive to motion artifact
Advantages of Ultrasound
No radiation Can be used in any plane Cheap Performed on sick patients Can provide real time imaging of heart, fetus
Disadvantages of US
Less sharp image
More time than CT
Highly variable depending on operator
Deeper structures (bone, lung) not well seen
Concerns about imagining of a pregnant women
CT is generally okay
-<50mGy (no effect)
MRI
-potential for fetal and amniotic fluid heating
Contrast agents
-iodine, oral contrast, and gadolinium not recommended
What is safe and dangerous limits of mGy depending on gestational age?
Only issues if about 100mGy
0-2=none 3-4=spontaneous abortion 5-10=possible congenital malformation 11-17=possible IQ defects 18-27=IQ defect >27=none
CBC
Complete blood count of all WBCs in blood
CBC w/diff
Measures total number of white blood cells in blood as well as gives actual number of each type of those cells
BMP ($12)
Chem7
-Na, K, Cl, Glucose, Creatinine, BUN, CO2
