Radiology; Lecture 4&5, Labs 3,4,5,&6
Terms
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- pain, paresis, paralysis
- What are the 3 signs of disk disease?
- Potter-Bucky Diaphragm
- A device that moves the grid back and forth under the table. Helps prevent grid lines from showing up on radiograph.
- more light
- Increased crystal size = _____________ given off
- Cadmium sulfide or caesium iodide
- What 2 types of screens does fluoroscopy use?
- negative
- What is different about pictures produced in fluoroscopy?
- 15 mAs
- What is our standard mAs for use with the grid on any body part?
- round ligament, joint capsule, muscles
- What 3 things hold the femoral head in the acetabulum?
- 5 mAs
- What is the standard mAs for our x-ray machine?
- Fast screen speed
- High speed-- decreased exposure-poor detail- are able to penetrate thicker areas
- You are using fewer x-rays
- Using screens leads to less radiation because ___________________________
- Blue
- What color light do calcium tungstate screens emit?
- Slow screen speed
- Have increased definition/detail- need to have increased radiation exposure
- dyes in phosphor layer
- pigments tend to decrease the lateral spread of light so there is increased detail. since there is decreased light you need to use more x-rays to get the same density in the radiograph
- 10 mAs
- What is our standard mAs for the pelvis, skull, spine and other bones?
- Flexed lateral view
- What position is required for OFA certification of elbows?
- Ostochondrosis dessicans- an idopathic disease, cartilage forms a flap which can break free and float in the joint
- What is OCD?
- Visible Light
- Crystals + X-rays = ___________
- Medium or Par screen speed
- Most common type-- give good resolution w/relatively low exposure
- Diskospondylitis
- Infection of the disk and surrounding bone
- Dobermans. Cervical instability & disks tend to have more movement than usual and are more apt to rupture
- What breed of dogs are prone to wobblers syndrome? What is it?
- Metastatic osteosarcoma
- Starts elsewhere in body and spreads to the bone
- weakness
- What is paresis?
- increased/ increased/ decreased
- Increased phosphor layer thickness leads to __________ x-ray absorption and __________ visible light emission from the crystals. This leads to ___________ detail due to blurriness from the spreading out of light
- Lines per Centimeter
- If the grid is stationary more lines that are finer are less apt to show up on the radiograph, few thicker lines show up more
- Laxicity caused by estrogen
- Why aren't females radiographed, 3-4 weeks before or after heat?
- Grid Focus
- What is the distance between the x-ray tube and the grid called?
- Fluoroscopy
- What type of radiography does not use x-ray film
- >_ 10cm
- When is the grid used on any body part?
- Film Cassettes
- Rigid film holders. Protect film from external light/damage. Keep x-ray film in close contact with screens, must be radiolucent
- Breed normals to normals, and make sure they have normal relatives
- Describe the genetic way of preventing hip dysplasia
- 15%cervical/ 85% Caudal thoracic and lumbar
- What are the 2 most common areas of disk herniation?
- Peak of exhalation
- When do you take the exposure of the abdomen?
- 4-9 months
- How early may radiographic signs of hip dysplasia appear?
- Inverse
- What kind of relationship does screen speed have w/exposure required to cause its fluorescence?
- Spondylosis
- Calcium binding between adjacent vetebrae
- Annulus fibrosis
- Outer fibrous layer of disk
- 24 months
- For official OFA radiographs, how old must the animal be?
- Osteosarcomas
- Bone tumors
- High levels of x-ray absorption/ High level of x-ray light conversion w/the correct energy & color for type of film used/ Must have little or now afterglow
- Screens need to have what 3 things?
- osteomyelitis
- Bone infection
- Fluid in joint/ fractures/ tumors/ bone infections. ocd
- What are 5 things that can be seen in a shoulder radiograph
- inversely
- Radiographic detail is _________ proportional to the screen speed
- Calcium tungstate and Rare earth elements
- What are the 2 types of phosphor crystals used in screens?
- Triple it
- What do we do to mAs when utilizing the grid?
- Anomalies
- Spine bifida, extra vertebrae, fused vertebrae, scoliosis
- 36-40inches
- How far away from the x-ray tube does the grid need to be?
- Caudal border of the scapula
- What do you center the beam over when x-raying the shoulder?
- Grid Cutoff
- If the x-ray tube is not with in the grid focus range, what occurs?
- Nucleus pulposis
- Gelatinous center of the disk
- Dachshunds, beagles and pekingese
- What breeds of dogs are prone to caudal throacic disk herniation?
- Animal ID(AKC # and Name)/ dob/ breed/ date/ owner id/ vet id
- What needs to be on the label for OFA
- slower/more/low
- small crystals= __________ screens= ________ detail= ________grain
- Blackness of a radiograph
- What does density refer to?
- Reflective layer efficiency
- Reflects light made by phosphors back towards the film. If it absorbs some light then it leads to decreased efficiency and need for more x-rays.
- +
- Do animals with hip dysplasia have a +/- Ortonali sign?
- polycarbonate/ aluminum/ magnesium/ carbon fiber/ vinyl
- What are 5 materials that film cassettes can be made of?
- Genetics/ Environment
- What are 2 ways of preventing hip dysplasia?
- fast, medium, slow
- What are the 3 speeds of screens?
- Fractures/ Tumors/ Dislocations/ Hip Dysplasia
- What 4 things do radiographs of the hips and pelvis show?
- Peak of inspiration
- When do you take the exposure of the chest?
- Quantum mottle
- Spotty or mottled appearance fewer x-rays hit fewer crystals. Deceased fluorescence. Seen more w/rare earth screens (fast screens)
- Intensifying Screens
- Sheets of luminescent phosphor crystals on a cardboard/ plastic base. 2 w/in each cassette.
- Green
- What color light do rare earth elements screens emit?
- Increased laxity felt when trying to "pull" the femoral head out of the acetabulum
- What is a (+) ortolani sign?
- Slow down rate of growth, start on adult food before 6 months . do not give vitamin or mineral surplus
- Describe the environmental way of preventing hip dysplasia.
- grid efficiency
- The ratio of the height of the lead strips to the distance between them
- 2.5 mAs
- What is the mAs value for our machine for radiographs of the chest?
- faster/less/high
- Large crystals=______ screens=________detail=_________"grain"
- >_15cm
- When is the grid used on the chest?
- Primary osteosarcoma
- bone tumor that starts in the bone
- A series of lead strips on edge which allow only primary x-rays to reach the film
- What is a grid?
- Sante's Rule
- What is kVp determined by?
- Malformation and degeneration of the coxofemoral joints
- What is hip dysplasia?