Kettering Big Players

All topics

Ionization

when an energy source contains sufficient energy to remove an electron from one of the orbital shells

characteristic energy is equal to

the difference between the electron binding energies of the orbital shell that contained the vacancy and the orbital shell that filled the vacancy

speed of light

3 × 10⁸ m/s

inverse square law

I1/I2 = (SID2/SID1)²

attenuation

the progressive absorption of the xray beam as it passes through matter. Absorption and scatter

xrays travel at

the speed of light

xrays have

high frequencies and very short wavelengths

compton interacts with

outer shell electron

law of bergonie and tribondeau

cell radiosensitivity is affected by
cell mitotic activity, maturity, degree of specificity

relationship of LET and RBE

directly related

radiolysis

radiation interaction with water that can combine to form free radicals

free radicals can form to create

hydrogen peroxide H2O2

10 days of lifespan shortening

0.01 Gy or 10 mgy

acute radiation syndrome

hematopoietic, gastrointestinal, central nervous system

minimum thickness requirements filtration

below 50 kvp none required (0.5mm inherent)
50-70 kvp (1.5mm)
70 and above (2.5 mm)

mobile cord length

2m, 180cm

lead aprons, gloves, bucky slot cover lead

0.5 mm, 0.25 mm, 0.25 mm

minimum source to skin distance fixed fluoroscopic units

15 in (38cm)

minimum source to skin distance mobile fluoroscopic units

12 in (30cm)

component of TLD reading

lithium flouride

component of OSL reading

aluminum oxide

annual whole body exposure occupational

50 mSv

cumulative effective limit dose

10 mSv x age in years

embryo/fetus gestational exposure

5 mSv

embryo/fetus monthly exposure

0.5 mSv

grid ratio

height/distance

if you use a grid what happens to mAs

has to increase

bucky factors

none: 1
5:1 2
6:1 3
8:1 4
10/12:1 5
16:1 6

penumbra is always greatest on

the cathode side of the beam

part thickness needs to be what when grid is required

10cm or 10-13cm

how does a tech adjust the rate of exposure when using an AEC device

+1 or +2 adjusts density control

pixel characteristics

smallest is better

pixel density determined by

pixel size and pixel pitch
when pixel size decreases, pixel density increases

dynamic range aka

contrast resolution, range of values over which a digital image receptor will respond; greater dynamic range will yield greater contrast resolution

to see a receptor change what do you do to mAs

30% change

actual focal spot always

larger

what is the best size focal spot for spatial resolution

smaller

xrays are produced

isotropically

leakage

1 mGy/hr at 1m

AEC purpose

reduce the number of repeated exposures taken on a mixed population. consistency and reproducibility on a wide variety of exams

devices from tube to IR

Tube
Pt
Table
Grid
AEC
IR
Bucky

purpose of backup timer

pt safety in case of equipment malfunction

what type of energy is supplied to xray tube

AC, 220-240V

transformers operate on

electromagnetic induction and AC current

Strength of EMF production is dependent on

speed, strength, angle, number of turns of conductor material

transformer turns ratio math problems

look over

mag mode consists of a ____ input phosphor size

small

magnifying flouro results in

increased pt dose, better spatial resolution, better contrast resolution

CR PSP plate order

Protective layer
Phosphor layer
light reflective layer
conductive layer
support layer
light shielding layer
backing layer

PSP active layer

europium-activated barium flourohalide

S number relationship

indirect (Fuji, Konica)

EI number relationship

direct (GE, Phillips, siemens, CSC, Kodak)

lgM number relationship

direct (AGFA)

scintillator converts

xray photons into light photons

equilization

method of image processing using the histogram of the image to adjust contrast. allows for the demonstration of a wide range of anatomical structures without overall loss of image quality

HIS

hospital information system contains full pt info

RIS

radiology information system contains radiology-specific information abt a pt including radiologists report and modality worklist reports

radiographic view

describes the body part as seen by the image receptor or other recording medium such as the screen

radiographic position

refers to a specific body position such as supine or recumbent.

xiphoid process location

level of T10

greater trochanter level

pubic symphysis

mesocephalic skull

typical. petrous pyramids anteriorly and medially at 47 degrees from MSP

brachycephalic skull

short front to back and broad side to side and shallow vertex to base
petrous pyramids 54 degrees

dolichocephalic skull

long front to back, narrow side to side, deep vertex to base
petrous pyramids 40 degrees

AP Axial skull CR

30 caudad or 37 if IOML, 2-3 inches superior to supercilliary ridge

Lateral skull CR

2 inches superior to EAM

PA Axial skull CR

15 caudad to MSP exiting nasion

Lateral facial bones CR

midway between outer canthus and EAM

Mandible axiolateral obliques

ramus- parallel
body- 30 degrees
symphysis- 45 degrees

spine c is called

horizontal beam

posterior obliques

Frech Fried Chicken

anterior obliques

Crunchy Crunchy Fries

scoliosis position preferred

PA

myelography is what type of injection where

intrathecal, subarachnoid space

AP hip best demonstrates

greater trochanter in profile laterally

CR AP hip

2.5in distal to the midpoint of the line drawn between the symphysis pubis and ASIS

clements nakayama is done why

bilateral hip fractures

Pelvis centering

15-20 degrees in feet. 2 inches superior to pubic symphysis

Judet affected side down

anterior rim of acetabulum and posterior ischial spine (ilioischial column)

Judet affected side up

posterior rim of acetabulum and anteriro ischial spine (iliopubic column)

why is chest at 72?

reduce heart magnification

on a chest xray how to distinguish between posterior ribs and anterior

posterior ribs touch the spine

posterior oblique ribs show

ribs closest to IR

anterior oblique ribs show

ribs furthest from IR

on an RAO where is sternum projected

left of vertebral column in the homogenous heart shadow

where to put pt legs on a KUB

hips and kees flexed to reduce lordotic curvature

upright abdomen should have

diaphragm included

if pt cannot sit upright on upright abdomen

keep the tube parallel to the floor anyway to demonstrate air fluid levels

trandelenburg on Upper Gi is for

hiatal hernia

on BE decub the area of interest is

where negative contrast is

BE posterior obliques show

side furthest from IR

BE anterior obliques show

side closest to IR

when performing a 25-30 degree posterior oblique position, you best demonstrate

upside kidney and downside ureter

calcaneus Axial CR

40 degrees to long axis of calcaneus entering at base of 3rd metatarsal

mortise foot obliqued degree

15-20 internally

AP Knee angles

below 19 cm 3-5 caudad
19-24 cm perpendicular
above 24 cm 3-5 cephalad

CR angle lateral knee

5-7 degrees

medial oblique knee demonstrates

open proximal tibiofibular joint space

why is forearm done AP

preferred to prevent overlap of proximal radius and ulna

lateral elbow fx sign

fat pad sign