Head and Neck Flashcards
why are plain films of the face not ordered anymore
hard to read so much overlap it is impossible might as well go right to a CT scan but they are fast and cheap
number of standard fews in face series
4
waters view
beam below the chin
jughandle view is helpful for looking at the
zygomatic arch Zygomatic arches = the “jugs”
highlights frontal/maxillary sinuses seen in what plain face XRAY
Water’s View
single lateral view
for nasal bone
CT indications
Significant trauma ○ Fracture present or suspected ○ Infections: sinusitis, periorbital cellulitis, retrobulbar pus, cavernous sinus thrombosis
facial infections we are worried about
sinusitis periorbital cellulitis retrobulbar (eye) pus cavernous sinus thrombosis need to know the extent and what is it
what are standard views for a CT of the face
Sagittal, coronal, axial recons -
Special CT views of the face
maxilofacial just the orbits (bony structures) of the eye very very thing cuts of the orbits)
why do you see maxillary sinus opacification
you can ask the houndsfield units to see if blood or infection or just look at the story
what is a blow out fracture
if the object fits into the orbit and push on the eye the eye will move back and the orbit will break BLOW OUT of the orbit fat will come out and in to the maxillary sinus (along with maybe blood or air)
“tear drop” sign refers to
blow out fracture with fat coming out into maxillary sinus
If the affected eye EOM’s impaired, they have ___________ and/or pain on looking up or out – suspect “__________”
If the affected eye EOM’s impaired, they have double vision and/or pain on looking up or out – suspect “entrapment”
direct blow to the cheek is known as a
tripod fracture you break the maxillary sinus and the orbit
NAME for Fractures in the zygomatic arch, orbit, wall of maxillary sinus ○ CT initial study
TRIPOD
Mid face fracture resulting from high force injuries
● LeFort fractures
types of LEFORT fractures
LEFORT 1: teeth fall off LEFORT 2: nose and teeth but orbit intact lefort 3: the bottom of your eyes fall off
Maxilla, or maxilla plus maxillary sinus/orbits/nose/arch in various degrees fracture involving
LeFort
plain film w/ circular view; takes horseshoe-shaped mandible and flattens it out
Panorex
what are the three things you need to describe a mandible fracture
Location & number of fx’s ○ Open or closed ■ Open means fx opens into mouth - worse b/c lots of bacteria in human mouth ○ Distraction (separation)
what is the order of operations for a mandible injury
PANOREX then CT for fracture or CT if it looks horrible ● Often fractures in >1 place due to horseshoe-shape
what is the diagnostic test of choice for suspected deep facial infx
CT is the diagnostic choice for suspected deep facial infections/pus collections or retrobulbar processes
test of choice in ED for retinal detachment (vision changes, halos, painless)
Ultrasound – Orbit
what should we normally see on the ultrasound of the orbit
● Normally, should see vitreous humor (black), retina should be flat in the back
welder comes in with eye pain they were not wearing safety glasses
ULS looking for metalic object
indications for CT imaging of TRAUMA
NEXUS Low Risk Criteria ○ Canadian C-Spine Rule ○ Both address who needs imaging and who does not
when to start of with a plain film of the neck
non trauma neck pain very minor trauma persistent neck pain can look for METS
in general obtain CT of the neck if
Significant mechanism (eg, freeway speed crash + neck pain) ○ Midline pain ○ Paresthesia/numbness/weakness ○ Cannot rotate or flex w/o pain ○ ALOC (alte —>Age>65 older and fall down you need this (8lb bowling ball on a stick)
3 views standard views for plain films of the neck
AP/PA views are most important in Chest; on AP view of Neck, top vertebra is usually C3 ○ 85% of diagnoses will be made with Lateral view ○ Open mouth odontoid gives better view of C1 and C2
85% of diagnoses will be made on what view on plain films of the neck
○ 85% of diagnoses will be made with Lateral view
three things that tell you if a lat neck film is adequate
Must be able to see the anterior superior corner (top of) T1 below C7 to evaluate alignment ○ Must see base of skull ○ Must see tips of C6, C7 spinous processes
what will you order if you can’t get an adequate neck xray
SWIMMERS view
systematic approach to reading lateral C spine films
1.name, date 2.COUNT 3.Check 4 lines of alignment 4.Look for consistent height/shape of vertebrae 5.Look for consistent disc spaces between bones 6.Look at soft tissue contours and spaces – measure if in doubt 7. Check all spinous processes for fx
Check 4 lines of alignment
- Anterior longitudinal ligament line = Anterior vertebral line 2. Posterior longitudinal ligament line = Posterior vertebral line 3. Spinolaminar line 4. Spinous process line
checking for alignment will tell you what about a lateral C spine xray
subluxation or ID abnormality
how much space should their be in front of C2
<6mm
how much space should their be in front of C3/4
<5 mm
how much space should their be in front of C6
<22mm at C6 ■ Kids: < ½ width V
how to remember the contour of the neck and the spaces
6mm at 2 22mm at 6
Pre-dental space (atlanto-dens interval should have how much space
≤ 3mm adults ■ ≤ 5mm kids
Reading the Odontoid View
Do the vertebral bodies of C1 and C2 line up? ● Look at symmetry of spaces between C1 and C2 ○ Is the pt rotated? Radiologist ● Look at contour of odontoid (dens) itself ○ Can you see the entire dens? ● Check lateral for clues too!
special neck views (other than swimmers)
Oblique views Flexion/Extension Views
old cspine view used for Neural foramina, facet joints ○ Less common ○ CT (fx) or MRI (spinal cord) are far superior
Oblique views
Less common ○ Not used in trauma ○ Controversial - may worsen sx’s ○ CT/MRI superior have to go to confession for a month
● Flexion/Extension Views
trauma C spine, contrast or nah?
nah, you’re looking at the bone
look at slide 37
CT MRI
when would you use MRI vs CT
if you suspect a deep space abscess the initial test is going to be a CT scan MRI for spinal cord injuries
these fractures are unstable much like the pt and the exact mechanism is unknown
● Odontoid fractures are unstable; quite often, the patient is also unstable
types of odontoid fracture
Type I, Type II, Type III
what would you do for suspected odontoid
CT scan as soon as possible once stabilized
= Fracture of the ring of C1 (like how lifesavers candy falls apart after sucking on it for a long time)
Jefferson Fracture
mechanism of a Jefferson fracture
axial load (something falling on your head, or diving into shallow pool)
how to dx jefferson fracture
*Confirm all fractures on CT scan by looking at image above and below for consistency
Posterior element fracture of C2; usually with hyperextension
Hangman’s Fx
mechanism of a hangman’s fracture
: hyperextension and compression (face vs. windshield) ● Soft tissue edema
burst fracture mechanism
axial load compression
Vertebral body in multiple pieces from unstable axial load compression
burst fracture doesn’t always violate the cord space but can be a very bad scene
mechanism of a wedge compression Fx
hyperflexion with axial load compression anteriorly
If posterior elements intrude on spinal canal on a wedge compression fracture
If posterior elements intrude on spinal canal, considered a burst fx
Flexion Teardrop Fx
: hyperflexion and compression (this is a diver’s fx)
ubluxation, Jumped or “Perched” Facets
mechnaism
hyperflexion with distraction
name this fracture
Perched facets is essentially a ligamentous injury; fixed w/ traction
how do you describe perched fx
Describe: top vertebrae is “subluxed onto” the lower one - % of vertebral body: “20% subluxation C5 onto C6”
hyperextension is the mechanism of this fracture seen with ligamentous rupture
Anterior Avulsion Fx
Anterior Avulsion Fx
stable fracture seen at the spinous process fx at C6 or C7
Clay Shoveler’s and Spinous Process Fx’s
name this fracture
what’s the mechanism
Clay shoveler’s
STABLE
Sudden hyperflexion; clay stuck to shovel when tossing overhead.
C6/7
Also caused by a direct blow to area.
● Classically, a ligamentous avulsion.
what is typical CM of epiglottitis
pain out of proportion to their findings, febrile, haven’t eaten
Sx: drooling, stridor, dyspnea
as them if they are inmmunized
what type of film would we get with a fish bone pt
soft tissue lateral of the neck underpenetrated (soft tissues need only)
24 yo man w/out immunizations when young, complains of a sore troat. positive thumb sign on soft tissue
epiglottitis
thumb sign
See enlarged epiglottis, classic “thumb” sign
what type of dx would you get with suspected retropharyngeal abscess
CT???
fever sore throat and trismus in a child
trismus= can’t open mouth
suspect retropharyngeal absces
what does ULS tell us about a thyroid
cystic (fluid) or solid (tumor), size, composition
need this before a FNA
thyroid scintigraphy, when is this indicated
Determines the functional status of a nodule (warm/hot/cold)
when would we use a ct for a thyroid
● CT reserved for complex cases, eval adjacent structures
– shows carotid/vascular flow; part of CVA work up
Duplex Ultrasound
– indicated for carotid dissection, trauma
CT angiography (CTA) –
● MR angiography (MRA) used for what in the neck
to study the vessels
History: A 45-year-old jumped into swimming pool and hit head, now with neck pain what type of fracture would you suspect
Jefferson fracture
