Last section Flashcards
In order to take a skull radiograph you need
general anesthesia
+/- remove ET tube
symmetry is key
Skull rad. views & where to measure
Lateral- measure highest point of zygomatic arch
V/D & D/V measure at highest point of cranium
Rostrocaudal: frontal sinus
dorsal recumbency with nose pointing at the tube
include entire forehead
beam should be centered through the front sinus
Rostrocaudal: Cranium
similar to caudal but nose is angled slightly dorsal towards belly
beam centered at midpoint between eyes
V/D Open mouth: Nasal cavity
maxilla parallel to cassette
mandible is as perpendicular as possible
beam centered through the level of the 3rd upper premolar
Rostrocaudal open mouth
Dorsal recumbency with the nose pulled cranial and mandible pulled caudal
Maxilla
Sternal recumbency
head in line with spine
corner of film inserted in mouth
Mandible
Similar to maxilla
dorsal recumbency
When to take a dental rad
Metabolic disease or neoplasia suspected Partially erupted or missing teeth Periodontal disease Extractions Oral trauma
Dental units
inexpensive
flexible head and joint extension arm
Can be used for more than dental rads
kVp and mA are usually fixed and time is adjustable
Most common dental film
D and E
D is 2x faster than E
Maxillary rads
sternal or lateral
film placed between tongue and maxilla
Mandibular rads
dorsal or lateral
film between tongue and mandible
Bisecting angle technique
betermine the plane of the tooth root & the plane of the film
estimate half the distance between the two and position the beam 90 degrees to that point
sternal or dorsal
Parallel technique
shooting film parallel to x-ray tube
“chair side” developer
dip in developer until color change evident
dip in wash 5 times
fix for 10 min. (clearing time 20sec)
rinse 20-30 min.
5 views of cervical spine
Lateral V/D Flexed Extended Hyper extended
Contrast medium
substance used to increase radiographic contrast
can be + or -
Barium sulfate
Positive contrast
only used in GI tract
Iodine based
Positive contrast
fill or outline hollow organs
Inj. into blood vessel or oral
Water soluble iodine base
Contraindicated for myography
Used when perforation is suspected
Oily viscous agents
Lymphography
Negative contrast
Radioleucent Increases contrast between tissue Pneumoperitineal studies CO2, O2, N20 CO2 preferred
Double contrast
Can use both + and - material at the same time
Survey film
Taken before the special procedure
Zero min. film
taken immediately after contrast material is given
Non-sequential studies
Must take survey and 0 min. film
Sequential studies
GI studies
series of films
movement involved
taken at 0,30,60,90 min.
Esophagography
\+ contrast given orally Megaesophagus dx non-sequential Include entire esophagus Lateral view
UGI study
\+ contrast Dx obstruction Sequential: 0,15,30, 60 & 90 min. Barium 12-24 fast & enema
LGI study
+, -, or double contrast into rectum, colon and secum
12-24hr. fast and enema
Anesthesia recommended
Gastrography
+,-, or double contrast
non-sequential
12-24 hour fast
Excretory urography
\+ contrast only admin IV survey film 12-24 hour fast have crash cart ready
Nephrogram
excretory urography
renal vasculature of kidneys
Pyelogram
excretory urography
eval of kidney structures
Cystography
Dx tumor, stones, bladder rupture \+,- or double non-sequential sedation recommended 12-24 hour fast and enema
Urethography
Retrograde- blocked tom
balloon tipped cath in urethra
admin from urethra up to bladder
Antegrade- tumors
from bladder to the outside
Myelography
+ contrast only
non-sequential
sterile
anesthesia required
Pneumoperitoneography
- contrast only
sedation recommended
sterile
can look at liver, spleen, stomach, distal colon, urinary bladder, uterus, abdominal wall
Arthrography
\+ or - contrast sterile, iodinated compound non-sequential sedation recommended look at joints, tendons, ligaments, cartilage
Vaginography
Uncommon \+ contrast sterile iodinated contrast eval of morphology of vaginal vault and repro tract anesthesia required non-sequential
Sialography
\+ contrast sterile, iodinated contrast look at salivary ducts & glands anesthesia required non-sequential
Angiocardiography
vascular system of heart
+ only
Angiography
entire vascular system
+ only
Cholecystography
bile ducts and gallbladder
+ most common
Lymphography
lymphatic system
H2O or Oily +
Fistulography
abdominal tract/opening
+ or -
Fluoroscopy
“live” xrays used to study motion
look at esophagus, upper and lower GI tract
Anesthesia discouraged
CT
Computed Tomography Uses x-rays and computer to produce images that show anatomy in cross section can show masses in mediastinum and brain can use contrast agent anesthesia necessary
MRI
Magnetic Resonance Imaging does not use xrays uses magnets to align the atoms con use contrast agent cross section pictures anesthesia necessary more detailed than CT
Nuclear Scintigraphy
Radioactive material administered to pt.
images provied less detail, but more physiological info
the material emits gamma rays
sedation necessary
“biohazard” for 24-72 hours
PET scan
Postion Emission Tomography
direct gamma rays
admin. FDG (glucose)
Ultrasound
Used in vet med. since the 1980s
Provides detailed info about organ structure
Distinguishes between fluid and solid mass
“real time” images
Fluid= black Solid= grey/white
Reverberation
Sound is redirected back to patient and received again by transducer
air scatters sound
Echogenocity
how sensitive a substance is to sound
increased= white (solid)
decreased= black (fluids)
Different frequency probes can be used depending on ____
size of animal
depth of organ or area
Higher frequency probe
better for resolution and detail
decreased depth
Info needed on ultrasound
Name of pt. Name of owner date of scan area/object being scanned Scan plane
Saggital scan plane
cranial to caudal
Transverse scan plane
sideways
