Radiology II Midterm

loroo's version from 2016-03-06 16:17

Physics [radiology term 2]

Question Answer
ratio of amount of heat compared to x-rays made during generation99/1
what does KVP control on xray machineenergy of photons
wavelength and energy are inversely related shorter waves are higher energy
x rays are (in relation to type of energy the produce)polyenergitic
cathode is what chargenegative
annode is what chargepositive
what direction to the electrons in the xray travel in relation to cathode and annodefrom the cathode to the annode
what is the main achievement of having a small filamenta smal focal spot and the image will have greater detail
what is a downfall to having a small filament?more energy, more heat, will burn out quicker
acceleration of electrons and ultimate striking energy is determined byKVP
what does the Mas setting on xray control# of photons created
how does the rotating anode xray generate e-rotating cathode getting equal distribution of e expose and this also dissipates heat
what are the 2 functions of the columaterdirecting the beam to reduce scatter and increase quality of film
scatter radiation is affected by KVP, patient size, and field size how?goes up with higher KVP, thicker patient size, and larger feild
what does an UNDEREXPOSED xray look like and how to you mend thislooks pale and you TURNT UP the KVP like light toast leave in oven too short
what does a film look like if its OVEREXPOSEDblack. like burnt toast you leave in oven too long
why is copper used in the annode?because it s a good dissapator of heat
how come tungston filament is used (why tungsten?)because it has a high melting point and such a high element number allows it to make more Electrons yo
two types of radiationgeneral and characterisitc
which type of radiation is the main exposure of the general public?radon
which type of radiation is called BRAKING RAYSgeneral radiation
if you notice that your MAS is too high how do you compensate?with MAS you normally change by cutting in half
what do you do to change your KVP if you notice it is off?change by 10% or 10 till you get it right
what is the main component of the tube in x-ray generation that makes the "Electron beam?"the focusing cup. (takes little e-s and says HEY! FOCUS PEOPLE)
what are some main ways to distribute heat in x-raysusing oil, annode has copper, tungstan filament has high melting point, rotating cathodes reduce friction, angling the annode so the beam isnt so intense
two types of x-ray detectionanalog and digital
which type of x-ray detection involves developer, fixer, and wash?analog
what is the main purpose of the fixer?removes remaining immulstion
what is the main purpose of developer?reducing agent that recpitates the silver out (what makes the black ness)
what affects the speed and sensitivity of exposure in film xray?the crystals in the film. The smaller the increases sensitivity but that means you need longer exposure
two types of digital radiographydigital and computed radiography
main diffrence between indirect and direct digital radiographindirect first convert visible light then get converted to electral and direct signal is p/u by plate and direct transfer to your computer
which type of detection have reusable plates?CR (gets an latent image -goes through a reader-then gets wiped clean by light )
miliamperage isnumber of electrons released
kilovoltagethe energy of the photons
MAS is whatmiliaperage times seconds
what are 3 diff ways you can get 10MAS(10ma x 1.0 s) (100Ma x 0.1 s) (1000ma x 0.01 s)
if you are using a grid what do you have to do normally? the MAS 5-8 times
when do you want to use a grid> 12 cm tissue thickness
what types of x-ray beamsprimary and secondary
grid helps whatabsorb some of the primary radiation and also secondary prevents fogging
in relation to the inverse square law if you moved the casette 2 meteres you reduce photons by1/4


Question Answer
four standard views of the bovine pastern lateromedial, dorsal palmar, dmplo, dlmpo
how do you describe the displacement of a fracture?the distal part in comparison to the proximal part
if you take a DMPLO what digit is in front on the film?lateral
which claw is the wieght bearing and there for larger claw in bovine front and hind limbin front limb its the medial claw (think as thumbs being more imp) in hind its the lateral claw (think of pinky toes being stabilizers)
what are two ways you could describe a leison in the boneproductive or destructive
most common reasons for leisons in the bovine claw/front limb?abscess or septicemic arthritis
how can you modify the lateral view to get a better visual on one claw?use a wooden block
dorsopalmer/planter projection comparison of adult versus immaturejuv
in horse which is the navicular bone?distal sesimoid
what is the pastern region?p 1, 2
take a peek at the ovine leg reconstructionshe likes the "gas" appearance immediately post op
Review sh fracturesyou gotta know that shit
what is the draining tract also referred to in a sequesterum?cloaca
new bone that surrounds the sequesterum is called involocrum


Question Answer
ALARA stands for?as low as reasonablity achievable
main radiation for public and percentageradon (80%)
what radiation causes a problem for us folksionization radiation
when would radiation cause problems for future genration of cells?if ionization radiation has penetrated into the DNA of that cell
effects of ionization radiation depends on whattype of particles, amount of exposure, amount of tissue exposed, type of tissue exposed, length of time (acute or long term)
what are some ways we can decrease scatter radiationuseing columater, distance, shielding, time of exposure
look at the 10 rules of basic safetyprobably important for life
are you protected fully if you place the lead glove over your hand while handling a cat that wants to eat your face off?no because scatter radiation can bounce off table and reflect up to your hands (cat wins either way)
lead protection protects you from what type of radiation?indirect (scatter) does not really do a good job protecting from direct
the us goverment of nuclear regulatory comission says you cant be exposed to more than what for radiation in one year5 rems
ionization of dna increases risk of 5mutation, abortion, susceptibility to disease, cancer CATARACTS



Question Answer
how many views are used to evaluate a horse thorax?4
what views are used to evaluate a horse thorax?craniodorsal cranioventral caudal dorsal caudal ventral side depends on what lung you are radiographing
what are "air bronchiograms"?air filled bronchus traversing an abnormal area of the lung that has fluid due to heightened ability to see air. Chest fluid
check out those species lung differenceshave to know for anatomy too LOVE VETMED
how many views do you normally take for a bovine thorax?normally 2 views suffice
whats the horizontal line?normally what you see in large animal with fluid in cavity. this is like the coffee pot example she used in class where you are standing so you have your fluid an then a line of reflection at that point
Why do we normally radiograph bovine thorax?hardware disease
what do you get to see in a dorsocaudal view of horse thorax?pulmonary a. pulmonary v., left and right crus and diaphragm
what do you see on a ventralcaudal view of horse thorax?trachea, carina, cvc, and diaphragm
what do you see on a dorsocranial view of thorax?trachea, aorta, carina, cvc
what do you see on a ventralcranial view of thorax?heart, humerous, scapula, trachea, cranial vena cava


Question Answer
main area we radiograph in a bovine?normally only do the cranial part of reticulum looking for obvious things like hardware disease
what signs might you see in a bovine with hardware disease on radiograph?gas cap, foreign body
why do farmers give their cows magnets to swallow?to hold on to those nails DUH
how can you tell if your magnet is working?on radiograph you can see if the nail associates with the magnet in a parallel fashion. If the nail doesn't do this it normally means its penetrated the tissue by then.
when do we radiograph horse abdomens?only when there is something extremely obvious like a fb, urolith, sand etc

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