radiology 101 chapter 7 continued

increased. lighter. additive, decreases

if a disease causes an increase in thickness, effective atomic # or density. there will be ______ attenuation of the beam producing a ____ image. the term for this disease is called ____ condition. density___ if no adjustments are made

less attenuation, darker , destructive, increases

if a disease causes a decrease in thickness, effective atomic # or densitythervwill be _____ attenuation of the beam producing a _____ image, the term for this type of disease is_____. condition. density ____ if no adjustments are made

quality is changes, quantity is changed

when kvp is changed what happens to the beam?

directly. increases

changing. kvp. (. directly or indirectly) affects density. so if increase kvp then density also ______

doubles, light

15 % rule. if you raise kvp by 15% then the intensity ______ you need to do this if image is too _______

grid, contrast

________ reduces the amount of scatter radiation. which in turn will improve radiographic _______

lower

in film screen radiography if you are using a higher speed film you will need to _______ mAs

increase, adjust mAs

if you increase film speed your density will _____. what do you need to do to prevent this ?

filtration,decreasing, 80

________ absorbs long wave photons before they reach the patient. increasing the energy of the beam, and ______ the dose to the patient by as much as ____%

slip on snap on portable cassette and part of table

5 types of grids

radiolucent and radiopaque strips,, radiopaque, whiteness, lead, radiolucent, plastic or aluminum, carbon

grids consist of 2 things. _____. _______ strips absorb scatter, creating. ______. usually mad a of ____ foil. ________ strips allows passage of radiation and are made of -------- cr. grids use ______

88-90, decreases, increase

grids absorb ________ % of scatter, this _______ density. so to maintain a proper density you muss _______mAs

developer temp to hot, immersion time increased, replenishment rates increase, ----- developer temp to cold, immersion time decreased, chemical contamination, replenishment rates decrease

film processes may affect the density of an image . density will increase. if (3). density will decrease if (4

contrast, to make anatomical parts visible

the difference bw adjacent material is ______ it's purpose is to _______

scale of contrast , long scale , short scale

the number of useful visible densities is refered to as ______. there are 2 categories. what are they

few , more, high contrast, low kvp

short scale has _____ shades of gray and _____ black and a bigger difference between densities. short scale has a -------- contrast. you can achieve short scale using ______

more, less, low, higher

long scale. has _____ gray with more densities but _____ differences between them. long scale has a ____ contrast. to achieve long scale you would need to use a _____ kvp

high,short

low kvp - _____ contrast - _____ scale

low,long

high kvp- ____ contrast-______ scale

decreases

increasing kvp ____. contrast

increases

decreasing kvp. _____ contrast

kvp

primary controlling factor of contrast

anatomy, beam restriction,grid,filtration,film processing,intensifying screen , contrast media

other influencing factors of contrast include

differentiate between 2 structures

recorded detail is how well you can ________

motion geometric, oid Sid focal spot, film

3 factors affecting detail

involuntary/ voluntary movement by patient , equipment

2 types of motion that can affect detail

smaller focal spot. because ther is less divergence of the beam

what type of focal spot will create a sharper image? why?

oid and sid

2 factors of size distortion

degree angulation direction of angulation,alignment of part,central Ray and ir

5 factors of shape distortion

divergence,decrease oid. , increase sid

______ causes magnification . 2 ways to reduce size distortion are _____

producing 2 dimensional image of a 3 dimensional object, foreshortening and elongation

shape distortion is common because______,
name 2 types of shape distortion

parrallel

object muss be _____ to image receptor to avoid shape distortion

close to , increase

to avoid size distortion keep the object ______ to film. as possible (oid). and if you need to decrease magnification _____ sid

perpindicular

the center Ray must be ______ to object in order to avoid distortion