RAD-Neck Flashcards
What are reason to get and NOT to get plain films for face?
PRO- cheap fast, less radiaton. CON- poor detail, ovelap. MINOR injury
What is the Water view?
Good for opacified sinus. -its taken with the patient tilting their head back or with the beam angled -good for looking at the inferior orbital rim, sinuses, and foreign bodies
What is the jughandle view?
Submental view-ideal for zygomatic arch fx
IF a suspected face fracture,then what is image of choice?
NON CON CT- CT great detail, get for signiifcant swelling, deformity, associ injury
If sinusitis, periobrital cellulits, retrobulbar put, canvernous sinus thrombosis, what is ordered?
CON CT- maxilo facial
What is seen on the blow out fracture?
EOM impaired, double vision, pain looking up and out= Entrapment inferior rectus. TEAR drop sign- fat falling through orbital floor. Plain-Water view. Gold standard CT*
This fracture of the face involves maxilla, zygoma, orbit from blow to cheek? What is study?
Lefort
Wha imaging modalities can we use to asses facial trauma?
-plain x-ray -CT scan -US **CT > x-ray
What is the submental view good for?
viewing the zygomatic arches
What are indications for obtaining a facial CT?
-get a non-con for suspected fracture -get w/ con for infection/mass (sinusitis, periorbital cellulitis, retrobulbar pus, cavernous sinus thrombosis) **CT is usually the first test
Do we always get imaging if we suspect sinusitis?
NO! A clinical diagnosis is reasonable.
What views are included in a standard facial CT?
-sagittal, coronal, axial recons
What are special CT cuts we can order for the face?
Maxilo-facial views + orbit thin cuts
What is the “tear drop sign”?
-indicates a blow out fracture -when trauma occurs directly over the eye and “pushes” the eye back -seen on plain film
What is a tripod fracture?
-direct blow to the cheek -zygomatic arch, orbit, lateral wall of maxillary sinus -CT initial study of choice
What is a LeFort fracture?
-occurs from significant mechanism -3 basic types -maxilla or maxilla plus maxillary sinus/orbits/nose/zygomatic arch in various degress -CT initial study
What is a panorex view used for?
To view the mandible. Has basically replaced plain film series.
Are plain films useful at imaging the c-spine?
they may be a useful initial study for non-trauma neck pain, mild radicular pain, very minor trauma and persistent neck sxs NOT ordered in significant trauma
What imaging modality is best if we suspect a spinal cord injury?
MRI
What are indications for a c-spine CT?
-significant mechanism -midline body pain -any paresthesia/numbness/weakness -cannot rotate or flex w/o pain -ALOC/intoxication with trauma -age >65
What are the 3 standard views in a neck plain film?
- AP 2. Lateral (most useful) 3. Open mouth odontoid view
How do we determine if a lateral film is adequate?
- Can we see the superior corner of T1 below C7? 2. Can we see the base of the skull? 3. Can we see the tips of C6, C7 and their spinous processes?
What is a swimmer’s view?
-if you are unable to see the entire cervical vert column AND the anterior corner of T1 we obtain this view -pt has one arm above the head and one arm dropped down to help expose the entire cervical spine
What’s the systematic approach to reading a lateral film?
- count the vertebrae: can we see C7 and T1?
- check 4 lines of alignment
- look for consistent height and shape of vert
- look for consistent disc spaces between bones
- check the C2 ring: overlap of lateral masses?
- look at soft tissue contours and spaces: measure if in doubt
- check all spinous processes for fracture
What 4 lines are we looking at on a lateral neck film?
- anterior longitudinal ligament line (anterior vertebral line) 2. posterior longitudinal ligament line (posterior vertebral line) 3. spinolaminal line 4. spinous process line
What are normal measurements for the pre-dental space?
= 3 mm in adults = 5 mm in kids
What’s the normal measurement of soft tissue at c2?
<6 mm
What’s the normal measurement of soft tissue at c6?
<22 mm
What are we looking at on an AP view?
-alignment -disc space -height, contour of vert bodies -spinous processes -transverse processes
How do we read the odontoid view?
-do the vertebral bodies of C1 and C2 line up? -look at the symmetry of spaces between C1 and C2? -look at contour of odontoid (dens) itself -check lateral for C2 ring distruption
What are special neck views?
- oblique 2. flexion/extension views
What are we looking for on an oblique plain film?
-neural foramina -facet joints -CT or MRI are far superior!!
What are extension/flexion views useful for?
-really just helpful at assessing alignment -never used in trauma -not common .
Would we get a CT w/ or w/o contrast for suspected fracture?
w/o
What are indications for a CT of the cervical spine?
-trauma -suspect frature/dislocation -need more detail about an x-ray finding -deep space information
What is an MRI or the c-spine definitive for?
- spinal cord injury 2. radiculopathy 3. abscess 4. tumor 5. pre-surgery (for a neck procedure)
What are the common causes of neck fractures?
- motor vehicle accidents = 50% 2. falls = 25% 3. sports = 10%
What assessing neck fractures what should we be looking at?
-first, we need to know the mechanism (flexion, extension, load, distraction, compression) -stable vs unstable -misalignment, swelling, uneven disc spaces -significant trauma -ALOA, focal neural deficit -should probably get a CT (bone) and an MRI (spinal cord)
Describe an odontoid fracture.
-unstable fracture -pt is often unstable -check the lateral for a C2 disruption
What is a Jefferson fracture?
-fracture of C1 -best seen on odontoid view -C1 lateral masses are not lined up with the C2 vertebral body -increased or uneven spacing between c1 and odontoid -mechanism is usually axial load -unstable
What is a hangman fracture?
-mechanism is usually hyperextension and compression -soft tissue edema common -C2 often seen “over-riding” C3 – subluxed -spinal cord damage at C2 common -unstable fracture
What is a burst fracture?
-mechanism is often axial load compression -common in C4-C6 -vertebral body fractured into multiple pieces -posterior elements encroach on spinal canal, compromise spinal cord -unstable fracture
What’s a wedge compression fracture?
-mechanism is often hyperflexion with axial load compression -anterior vertebral body compressed into a “wedge” -posterior area of vert body may be maintained -if posterior elements intrude on spinal canal –> consider burst fracture -unstable fracture
What’s a teardrop fracture?
-aka anterior flexion or extension fracture -aka avulsion fracture -mechanism is hyperflexion or hyperextension -ligamentous disruption anteriorly, avulses the bone causing a small teardrop -force causes “retropulsion” of vert body fragments into spinal canal –> cord compromise -unstable
What are subluxation, jumped, perched facets?
-mechanism is hyperflexion with distraction -+/- fracture w/ subluxation -perched/jumped facets is essentially a ligamentous injury -ant and post vert lines of alignment are off -cord compromise possible -unstable
What is a clay shoveler’s fx?
-spinous process fx at C6 or C7 -mechanism is sudden hyperflexion -named b/c clay gets stukc to the shovel when tossing overhead -classically, a ligamentous avulsion -usually stable!!!
What is a soft tissue lateral?
-special x-ray view -useful for epiglottis, retropharyngeal abscess and swallowed foreign bodies -CT scan is often ordered first
How does epiglottitis appear?
-soft tissue lateral is first test UNLESS there is high suspicion then get a CT first -do not need C7/T1 -epiglottis is an anterior structure, usually a thin fingerless soft tissue density at the level of the hyoid bone
What’s the “thumb sign”?
an enlarged epiglottis appears thumb like!
How does a retropharyngeal abscess appear on imaging?
-see soft tissue edema/mass in retropharyngeal psace -soft tissue lateral ok if high suspicion, but high false negative rate -CT is superior imaging
What’s the initial imaging test for a thyroid nodule/mass?
Ultrasound
What does an ultrasound of the neck tell us?
-size, composition of the mass -US-guided fine needle biopsy
Can an US alone be used to diagnose cancer?
No! We need a biopsy.
What is thyroid scintigraphy?
-a nuclear medicine study -can help determine the functional status of a nodule
If thyroid scintigraphy the initial test for a thyroid nodule/mass?
Not anymore, its US now!
When would we CT a thyroid nodule/mass?
CT is reserved for complex cases to evaluate extent and adjacent structures
What are vascular studies?
-duplex US -CTA -3-D enhanced CTA -MRA -traditional angiography
What are duplex US used for?
-carotid/vascular flow -part of a CVA workup
What is a CTA used for?
CVA, carotid dissection, trauma
What is traditional angiography? Do we use it often?
-plain film with dye -used less than CT or MRA
