Radiology

Question 1

Modalities

Answer 1

the different imaging technologies

Question 2

list of modalities

Answer 2

1. Radiography (X-Rays, Flat plate, radiographs, plan films, computed radiography CR, Digital Radiography DR
2. Fluoroscopy
3. Nuclear Medicine
4. Ultrasound
5. Computed Tomography
6. MRI

Question 3

X Rays

Answer 3

A form of electromagnetic wave - photons, traveling at the speed of light. They can expose photographic film or cause fluorescence

Question 4

the shorter the wavelength

Answer 4

the greater the energy

Question 5

x rays can cause

Answer 5

ionization - where you strip off an electron and change the molecule

Question 6

higher the x ray dose

Answer 6

the higher the health risk (low doses are environmental/natural)

Question 7

Electromagnetic wave spectrum

Answer 7

Radio MRI RV Micro Radar IR Vis UC X Ray Cosmic Gamma

Question 8

frequency

Answer 8

waves in 1 second

Question 9

wavelength

Answer 9

peak to peak

Question 10

Radiography

Answer 10

X ray tube emits ionization radiation. X rays pass through patient. Rays strike a digital imaging plate. Results image displays 2D shadow.

Question 11

Can X rays be focused/.

Answer 11

No so they have a lead column to keep them in

Question 12

radio graphic densities ranked from low to high

Answer 12

1. Air (lungs, bowel, gas)
2. Fat (Adipose)
3. Water (muscle, liver, etc)
4. Bone
5. Metal

Question 13

Thickness on radiographics

Answer 13

matters

Question 14

Radiographic advantages

Answer 14

fast, inexpensive, available everywhere, demonstrates bone and metal very well

Question 15

Radiography Disadvantages

Answer 15

Uses ionizing radiation (RRL for CXR is 1/5), Limited information for soft tissues, artifacts (superimposed shadows, magnification, blurring bc motion)

Question 16

RRL

Answer 16

relative radiation level

Question 17

what do you call something bright on an x ray image

Answer 17

radiopaque or radiodense or high density

Question 18

what do you call something dark on an x ray image

Answer 18

Radiolucent or low density

Question 19

Fluoroscopy

Answer 19

Continuous x rays are passed through the patient onto a fluoroscope. If a radiograph is like a photograph then fluoroscopy is like a movie. The exam is monitored on a video monitor, then recorded on video or still images. It may be portable to guide surgeons. And it often utilizes a contrast agent

Question 20

Fluoroscopy advantages

Answer 20

Can see inside of bowel, bladder, heart chambers, thecal sac, etc. Real time visualization, moderate expense, can be used for interventional procedures

Question 21

Fluoroscopy disadvantages

Answer 21

Can accumulate significant radiation exposure for patient and personnel (RRL 3/5 or 4/5), Contrast agents can be unpleasant or can cause allergy or nausea,

Question 22

interventional procedures

Answer 22

not a particular modality, rather is all of the minimally invasive procedures performed by radiologists (also surgeons, cardiologists, etc) using imaging guidance

Question 23

examples of interventional procesdures

Answer 23

Biopsies, Arthrograms, Draining procedures, IV catheter placement, stopping hemorrhage, treating stroke, etc

Question 24

interventional advantages

Answer 24

is both diagnostic and therapeutic, it is minimally invasive compared to open surgeries and less expensive (but still a lot of money).

Question 25

Interventional disadvantages

Answer 25

Complications, blood product exposure to personnel, radiation (RRL 2/5)

Question 26

Nuclear Medicine

Answer 26

A radionucleotide + physiologic analog = radiopharmaceutical, Radiopharmaceutical usually given via IV but may be ingested, infused to the urinary bladder, in the thecal sac, etc. Gamma rays project from radiopharmaceutical, Gamma camera detects these rays and a computer generates digital images

Question 27

NM examples

Answer 27

Bone scan, myocardial perfusion imaging/nuclear stress test, HIDA scan, Iodide with uptakes, PET, tag white blood cell, thyroid ablation

Question 28

NM Advantages

Answer 28

Excellent at showing the function of organs

Question 29

NM Disadvantages

Answer 29

Do not see organ anatomy in great detail, expensive, ionizing radiation (3/5-4/5)

Question 30

synonym for NM

Answer 30

Scintigraphy

Question 31

how is revealed anatomy described (NM)

Answer 31

as having increased uptake or hot or photon rich

Question 32

how is anatomy not or less revealed described (NM)

Answer 32

as decreased uptake, cold, photon poor, photopenic

Question 33

Ultrasound synonym

Answer 33

sonography

Question 34

revealed anatomy in US

Answer 34

echogenic. If seen more so it is Hyperechoic, if less so then Hypoechoic. If not seen it is Anechoic

Question 35

US Advantages

Answer 35

Relatively inexpensive, no ionizing radiation (idea for OBGYN or kids), Real time, give both anatomic and dynamic information, Doppler technique shows blood flow (not other contrasts needed), imaging in any plane

Question 36

US Disadvantages

Answer 36

Hard to see deep structures, difficult with obese or immobile patients, cannot see well through bone or air, looks like weather map to untrained eye

Question 37

Computed Tomography (CT)

Answer 37

An X ray tube and multiple detectors are revolved/spirals around the patient. The detector plates measure attenuation (loss) of radiation passed through the patient. Digital images are produced and displayed by a computer.

Question 38

CT Lingo

Answer 38

bright = High attenuation. Dark = low attenuation

Question 39

CT Advantages

Answer 39

Excellent cross sectional anatomy, rapid, widely available, tremendous radiographic density resolution (1500x more than x ray), excellent guidance for interventional procedures, non-invasive vascular imaging (but need IV contrast for this).

Question 40

CT Disadvantages

Answer 40

Costly, Cumbersome for the very ill, ionizing radiation (RRL for abdomen is 3/5), Metal or dense bone artifact

Question 41

MRI

Answer 41

strong magnetic fields are used to align body protons (H). Radio waves (radiofrequency/RF pules) are transmitted to the protons. The protons absorb the radio wave energy, then change the way they spin. This is detected, processed, and displayed by a computer

Question 42

MRI Lingo

Answer 42

``` bright = high signal intensity dark = low signal intensity ```

Question 43

MRI Advantages

Answer 43

Excellent cross sectional anatomy, no ionizing radiation, images directly in any pane, noninvasive vascular imaging, generally available

Question 44

MRI Disadvantages

Answer 44

Cost, contraindicated for some patients (pacemakers, defibrillators, claustrophobic, etc), artifact from motion, metal, etc.

Question 45

PACS

Answer 45

picture archiving and communication services

Question 46

HIS

Answer 46

health information system

Question 47

ways of accessing images and info

Answer 47

PACS and HIS