Neuro-temporal bone, orbit & skull base/neck Flashcards
Longitudinal vs transverse temporal bones fractures
- Long: long axis, MC, more ossicular dislocation, conductive hearing loss
- TV: short axis, van injury, sensorineuronal
MC facial fracture
nasal bone
MC facial fracture pattern
zygomaticomaxillary complex fracture (tripod)-zymgoma, inf orbit, lateral orbit
Le-Fort Fractures
involve pterygoid process
1) floating palate-anterolateral margin of nasal loss
2) pyramidal-inferior orbital rim & floor
3) separated face- zygomatic arch, lateral orbital rim wall
MC fracture site to result in CSF leak
anterior skull base
“recurrent bacterial meningitis”
known association with CSF leak
What is the best predictive factor ISO temporal bone fx?
otic capsule violation
Division of middle ear cavity
- epitympanum
- hypotympanum
- mesotympanum
hypotympanum-where, what arises from it?
- Below tympanic membrane.
- Eustachian tube arises from here.
epitympanum
- “attic”
- above tip of scutum
mesotympanum
-directly behind tympanic membrane
Two parts of tympanic membrane
1) pars flaccida (top, weaker)
2) pars tensa (bottom)
cholesteatoma-what, specific sgx, MRI img
blob of exfoliated skin in middle ear cavity secondary to hole in pars flaccid.
- erosion of scutum (v. specific sgx)
- RD+
Two types cholesteatoma
1) pars flaccida
2) pars tensa
Pars flaccida type cholesteatoma
- MC
- Prussak’s space= MC loc
- Early erosion scutum
- long process incus MC segment of ossicular chain to be eroded
- fistula to SCC MC involve lateral segment
pars tensa type cholesteatoma
- less common
- inner ear involvement occ MC & earlier
prussau’s space
btw incus body (medial) and temporal bone process/scutum (lateral)
otic capsule aka
- bony labyrinthine
- SCC, vestibule, cochlea
- normally fluid filled
labyrinthine fistula (perilymphatic fistula)
- 2/2 cholesteatoma, iatrogenic, trauma
- abN conn with MEC (air-filled)
- Lat SCC MC involved
- “sudden fluctuating sensorineural hearing loss & vertigo)
imaging labyrinthine fistula 2/2 cholesteatoma
- ST density eating through otic capsule into SCC
- pneumolabyrinth-not often seen
“chronic” OM
fluid in MEC >6wks
In whom is OM common?
kids & DS (horn Eustachian tube)
complications of OM
1) coalescent mastoiditis-erosion mastoid septa w/ or w/o intramastoid abscess
2) facial n palsy-2/2 inflammation tympanic segment
3) dural sinus thrombosis–> venous infarct, otitic hydrocephalus
4) meningitis, labyrinthitis
labyrinthitis ossificants
“hx of childhood meningitis”
- kids, 2-18 mo’s
- img: ossification of membranous labyrinth
- sensorineural hearing loss
- calcification of cochlea CI for cochlear implant
membranous labyrinth
- soft tissue lining bony labyrinth (the series of canals tunneled out of t-bone)
- further divided into cochlear & vestibular labyrinths
labyrinthitis
- inflammation of membranous labyrinth
- viral URI (MC), otomastoiditis (UL), bacterial meningitis (BL)
- img: cochlea & SCC enhancement
6 segments FN. Which normally enhance?
- I Must Learn To Make Expressions
1) intracranial (cisternal)
2) meatal (canalicular)-inside IAC
3) labyrinthine (IAC–> geniculate ganglion) +
4) tympanic (GG–> pyramidal eminence) +
5) mastoid (pyramidal eminence–> SMF) +
6) extratemporal (distal to SMF)
What causes abnormal enh of the FN? When do you think cancer? When do you damage the FN?
1) Bell’s palsy (MC), Lymes, Ramsay Hunt, Cancer
2) nodular enhancement
3) T-bone fx (transverse > long)
Bell’s Palsy classic img finding
enhancement of canalicular segment (in IAC)
Ramsey hunt
- 2/2 varicella zoster reactivation
- rash around ear
- CN 5 & 7 involvement
otosclerosis-what, who, pres, types, mx
- Aka otospongiosis. Bony resorption of bony labyrinth.
- conductive hearing loss in elderly
- types: fenestral and retro fenestral (cochlear) types.
- rx: Flouride dietary supplement. stapedecetomy, cochlear implant.
Fenestral type otosclerosis
- Bony resorption starts at anterior margin of oval window (fissula ante fenestram). No cochlear involvement.
- If unrx, footplate will fuse to oval window.
retro-fenestral/cochlear type otosclerosis-what, img, bilaterally, pres
- more severe
- progression to demineralization around cochlea
- BL, symmetric 100%
- +sensorineural
superior SCC dehiscence
- aunt minnie
- 2/2 long standing (+) ICP
- “noise-induced vertigo”. “Tullio’s phenomenon”
“noise-induced vertigo”. “Tullio’s phenomenon”
superior SCC dehiscence
conductive hearing loss in elderly
otosclerosis
large vestibular aqueduct syndrome-mo, pres, UL vs BL, findings
- Aunt Minnie.
- > 1.5 mm, larger than adj PSCC
- 2/2 failure of endolymphatic sac to resorb endolymph–> endolymphatic hydrops & dilation
- mcc congenital SN hearing loss
- often BL
- cochlear deformity (~100%), abscent bony modulus >90%)
- “progressive sensorineural hearing loss”-not born with it!
vestibular aqueduct
- bony canal that connects vestibular with endolymphatic sac
- should never be > PSCC
congenital malformations inner ear
- michel’s aplasia-earlier (3rd wk), most severe, rare
- classic mondini’s malformation-latest (7th wk), least severe, common
Mondini Malformation
cochlear hypoplasia of middle & apical turns (fuse into cystic apex –> 1.5 turns)
- ass w/ enlarged vestibule, enlarged vestibular aqueduct
- SN hearing loss (but high frequency sounds preserved via basal turn!)
Michel’s aplasia/complete labyrinthine aplasia (CLA)-what, when, ass, findings, how to differentiate from a mimic
- Earliest (3rd wk) & most severe of congenital abN of inner ear. V rare
- absent cochlea, veestibule, vestibular aqueduct
- completely deaf
- ass w/ anencephaly, thalidomide exposure
- some people think it looks like labyrinthitis ossificans (look for absent vestibular aqueduct to help differentiate!)
How to differentiate Michel’s aplasia from labyrinthitis ossificans
absent vestibular aqueduct in CLA
endolymphatic sac tumor-ass & imaging.
- sporadic. Ass w/ VHL
- img: int amorphous Ca, T2+, enh+++, FV, tumor blush on angiography
paraganglioma of jugular fossa
- Glomus jugular & jugulotympanic tumors
- can invade occipital bone and adjacent petrous apex
- 40% hereditary, multiple
- MC presenting syx=hoarseness from VN compr
petrous apex anatomic variations
1) asymmetric marrow
2) cephalocele
3) aberrant internal carotid
How to avoid misinterpreting asymmetric petrous apex marrow signal
STIR/fat suppression
*marrow signal follow that of scalp & orbital fat (T1/T2+)
petrous apex cephalocele-what? BL vs US. Classic img.
- misnomer bc doesn’t contain brain tissue
- aka “petrous apex arachnoid cyst”
- acquired or congenital herniation of PL wall of Meckel’s cave into superomedial petrous apex
- BL > UL
- “smoothly marginated lobulated cystic expansion of petrous apex.”
“smoothly marginated lobulated cystic expansion of petrous apex.”
petrous apex cephalocele
how will examiners try to fool you re: aberrant internal carotid
calling it a paraganglioma. look for conn to horz carotid canal.
aberrant internal carotid-MOA, pres, img, mimic?
“pulsatile tinnitus”
- C1/cervical segment involuted/under developed –> middle ear collaterals level (enlarged caroticotympanic a)—> hypertrophied vessels run through tympanic cavity and join carotid canal
- ENT exam: vascular mass pulsing behind ear drum.
- vs paraganglioma-connect to horz carotid canal
Apical petrositis
- 1˚ in children. 2˚ in adults from otomastoiditis.
- –> skull base OM, ICA vasospasm, subdural empyema, venous sinus thrombosis, TL stroke, meningitis
gradenigo syndrome
complication of apical petrositis when dorellos canal is involved –> lateral rectus palsy
-classic triad: otomastoiditis, face pain, lateral rectus palsy
cholesterol granuloma
MC 1˚ petrous apex lesion.
- obstruction of air cells –> repeated hem/inflamm –>bone expansion/remodeling
- MC syx=hearing loss
- T1/T2+
- rx fast growing ones surgically
petrous cholesteatoma
- congenital (vs MEC)
- slow growing, ass bony change
- T1(-), T2 (+), RD+
- smooth expansile bony change
smooth expansile bony change of petrous apex
- cholesterol granuloma (T1+, RD-)
- cholesteatoma-T1-, RD+
external auditory canal exostosis
- overgrowth tissue in EAC seen in surfers who get repeated bouts of ear inf
- if chronic=bone
- BL
external auditory canal osteoma
benign bone growth near junction of cartilage and bone in ear canal
external auditory canal atresia-what, findings, what does surgeon want to know?
-EAC doesn’t form.
+/- mashed up ossicular chain
-ENT cares about 1) ST or bone covering opening 2) aberrant facial n course?
“osteolysis circumscripta”
pagets
MC 1˚malignancy of the globe in children?
Retinoblastoma
retinoblastoma-pathology, epidemiology, appearance
- Rb suppressor gene on chromosome 13 (unlucky 13) (same as OS)
- peds (~3 yo)
- eyeball size: N/L.
- Ca+
chromosome 13 pathology
- Rb
- osteosarcoma
- Rb patients (+)risk facial osteosarcoma after radiation.)
Rb: bilateral, trilateral, quadrilateral
- Bilateral-both eyes. 30%
- Trilateral- +pineal gland
- Quadrilateral- +suprasellar
Coats’ Disease
retinal telangiectasia–> leaky blood & sub retinal exudate–> retinal detachment
- vs RB: no ca, small globe.
- CT dense, T1/2+
persistent hyper plastic primary vitreous (PHPV)
failure of embryonic ocular bs to regress –> retinal detachment
-microphthalmis + vitreous increased density. No Ca
size of globe in toxocariasis
normal
Causes of microphthalmia
- persistent hyper plastic primary vitreous (PHPV) (normal before birth)
- retinopathy of prematurity-BL small
- coats’
retinal detachment
- causes: PHPV, Coats, trauma, sickle cell, old age
- V or Y shape (listen up retinal leaves & sub retinal fluid)
melanoma
- mc intraoccqular lesion in adult
- collar but shaped related to Bruch’s membrane
- stong predilection for liver mets-next step liver MR
optic n glioma
- sporadic <20 yo, GBM
- BL: NF-1, Who Grade 1 pilocytic astrocytoma
- enlargement of entire nerve
“tram-track calcification” optic nerve sheath meningioma
optic nerve sheath meningioma
“doughnut appearance with circumferential enhancement around optic nerve.”
optic nerve sheath meningioma
mc benign congenital orbital mass
dermoid
- classic loc: superolateral, from frontozygomatic suture
- <10 yo
rhabdomyosarcoma
- mc extra ocular orbital malignancy in children
- superior-medial orbit
- bone destruction
- “bully orbital mass in a 7 yr old”
orbital lymphoma
ass with Chlamydia Psittaci (bird fever) & MALT
- upper outer orbit, closely ass w/ lacrimal gland
- homogenous enhancement, RD+
metastatic neuroblastoma
- “raccoon eyes” on PE
- periorbital tumor infiltrate + proptosis
- BL sphenoid greater wing
bony involvement greater wing of sphenoid
- BL=NB
- UL=EWL
metastatic scirrhous (fibrosing)
2/2 breast cancer
-desmoplastic rxn –> enophthalmos (pst displacement globe)
infiltrative retrobulbular mass + exophthalmos=
Breast scirrhous carcinoma
what do orbital pseudotumor, tolosa hunt syndrome & lymphocytic hypophysitis all have in common?
IgG4 related
orbital pseudotumor
- IgG4 related idiopathic inflamm
- UL LR
- myotendinous insertions not spared & pain (vs graves).
- EOM+, T2-, enh+
tolosa hunt syndrome
- IgG4 related idiopathic inflamm
- cavernous sinus. painful. multiple CN palsies
lymphocytic hypophysitis
- IgG4 related idiopathic inflamm
- pituitary gland stalk enlarged in post-partum/3rd TM F.
- Vs pituitary adenoma: T2 dark rim
MCC exophthalmos
thyroid orbitopathy
thyroid orbitopathy
- TSH rec ab’s –< orbital fibroblasts & adipocytes
- confined to EOM m body enlargement
- risk of compressive optic neuropathy
- painless
thyroid orbitopathy order of EOM involvement
IR > MR> SR > LR >SO/IO
thyroid orbitopathy vs orbital pseudotumor
TO m belly only and painless
orbital lymphangioma
- venous and lymphatic malformations
- ill defined, no capsule
- multi-spatial-preseptal, post septal, extraconal, intrazonal.
- F/F levels classic
- don’t distant with Valsalva maneuvers
orbital varix
- massive dilation of valveless orbital v’s 2/2 weakness in post-capillary venous wall
- distend with provocative maneuvers
mcc spon’t orbital hemorrhage
orbital varix (thrombose + pain)
intraconal space
inside rectus muscle pyramid
extraconal space
space outside rectus m pyramid
insertions of orbital septum
periosteum of orbit –> palpebral tissue along tarsal place
where do pre- and postseptal infections arise from?
- pre: teeth, face
- post: paranasal sinus
mcc periorbital abscess induced thrombosis of opthalmic v or cavity sinus?
aspergillosis
dacryocystitis
Aunt minnie
- inflamm & dil lacrimal sac 2/2 obstruction –> bacterial inf (staph, strep)
- well circumscribed, round enhancing lesion centered in lacrimal fossa
- CT if peri-orbital cellulitis
MCC orbital subperiosteal abscess
Aunt minnie
-ethmoid sinusitis
optic neuritis
nerve enh without enlargement
- UL (70%), painful
- Devics & MS
optic n enhancement + enlargement
glioma…NF-1!
papilledema
dilation/swelling optic nerve sheath
drusene
- mineralization at optic disk
- ass w/ age-related maculopathy
intraocular lens implant
standard treatment for cataracts
-implant = thin, linear
ectopia lentis
- lens dislocation
- causes: trauma, marfans, homocystinuria
coloboma
- failure of choroid tissue to close –> focal discontinuity of globe
- posterior.
- UL = sporadic
- BL= CHARGE
“sudden fluctuating sensorineural hearing loss & vertigo”
labyrinthine fistula
MCC’s labyrinthitis
-URI (MC)
otomastoiditis (UL)
-bacterial meningitis (BL)
“hx of childhood meningitis”
labyrinthitis ossificans
MC presenting symptom of jugular paragangliomas
hoarseness from VN compression
What percent of jugular paragangliomas are hereditary (and likely multiple)
40%
clivus chordoma vs chondrosarcoma
chordoma=midline, chondrosarcoma off midline
McCune Albright Syndrome
MF fibrous dysplasia, cafe-au-lait spots, and precocious puberty
Pagets of the skull- inner vs outer table
favors inner table
Paget’s skull related complications-which is MC
- deafness (MC)
- CN paresis
- basilar invaginations–> HCP–> BS compression
- 2˚ OS (high grade)
which part of the skull does fibrous dysplasia classically spare?
otic capsule
which part of the skull does FD favor?
outer table
When would you use CT in sinus disease?
- sinus & orbital infections (anterior 2/3 orbit)
- Diff infection from tumor (inf hyperdense)
- Anatomic variation
When would you use MRI in sinus disease?
- Cavernous sinus involvement or pst 1/3 orbit.
- tumor progression/extension (perineurial, marrow)
hyperdense sinus
- blood
- dense (inspissated) secretions
- fungus
fungal sinusitis-types
1) allergic
2) acute invasive fungal
allergic fungal sinusitis-what is it, location, appearance (CT & MR), immune status
- chronic allergic fungal sinusitis via hypersensitivity run to fungus
- immunocompetent, hx asthma
- mult sinuses (usually BL ethmoid & MS)
- CT: dense centrally or w/ layers/curvilinear. chronic= bony erosion/remodeling.
- MR: T1/2 (high protein/heavy metals). Can mimic aerated sinus! Mucosa T2+ (inflamed). Fungal blob will not enhance.
What’s in it? Infraorbital canal/foramen
infraorbital vessels & n
acute invasive fungal sinusitis-appearance (CT & MR) immune status.
- mult sinuses. *Periorbital fat extension
- immunocomromised- neutropenic (aspergillus), DM in DKA (zygomycetes/mucor)
- ct- not hyperdense. Fat stranding (orbit, masticator far, pre-antral fat, PPF=invasion). No bone change required
- MR-T1/T2(-) Mucosa +/- enh, ie: (-) in necrosis. extra sinus disease= STIR+, enh.
chronic inflammatory sinonasal disease
inflammation >12wks.
osteomeatal unit (OMU)
- common drainage pathway for maxillary, frontal and anterior ethmoid sinuses
- maxillary sinus esteem, infundibulum, uncinate process, hiatus semilunaris, ethmoid bulla & middle meatus (some authors include frontal recess)
What part of OMU is blocked in isolated maxillary sinus disease?
maxillary sinus osteium or infundibulum
What part of OMU is blocked in maxillary, frontal & anterior ethmoid sinus disease?
-hiatus semilunaris
Which is the largest paranasal sinus?
maxillary
How is ethmoid sinus divided? What divides it? Differences in drainage?
- Ant: frontal recess–> middle meatus (OMU)
- Pst: drains via tiny ostia under superior turbinate into superior meatus.
- divided by basal lamella
What sep ES from orbit?
lamina papyracea
What lines the sinuses?
ciliary mucosa
what does frontal sinus represent at birth?
enlarged anterior ethmoid cell, ie: not formed at birth
drainage frontal sinus
into ethmoid infundibulum via frontal recess
drainage sphenoid sinus
into ethmoid air cells via sphenoethmoidal recess
overview sinus drainage:
- frontal –> frontal recess –> ethmoid infundibulum –> OMU –> middle meatus
- sphenoid –> sphenoethmoidal recess–> pst ethmoid air cell
- ant ethmoid –> frontal recess
- pst ethmoid–> unnamed ostia (under sup turbinate)–> superior meatus
- maxillary: maxillary sinus ostium –> infundibulum –> hiatus semilunaris –> middle meatus
FESS-acronym
functional endoscopic sinus surgery
Important things to not re: preoperative FESS imaging
anatomic variations: dehiscent lamina papyracea, dehiscent cribriform plate
dehiscent lamina papyracea- imaging appearance and clinical consequence in FESS
- medial bulge of orbit
- enter orbit
dehiscent cribriform plate-imaging appearance and clinical consequence in FESS
- inferior bulge of frontal lobe
- enter FL
Agger nasi cell-what is it, clinical consequence?
“nasal mound”. Most anterior air cell.
-may cause obstruction of FS if large
Haller cell- what is it, clinical consequence?
ethmoid cell inferior to orbit
-compromise maxillary osmium if enlarged or inflamed
Onodi cell- what is it, clinical consequence?
- most posterosuperior ethmoid air cell
- directly inferomedial to optic nerve
- may be mistake for optic nerve endoscopically–> damage
concha bullosa-aka, what is it, locations, clinical consequence?
- aka “concha/tubinate pneumatization”
- extension of sinus into concha –> pneumatization 50%+ vertical heigh of middle concha
- may cause septal deviation, narrowing of infundibulum when large
pott’s puffy tumor
subgaleal abscess + ST edema 2/2 OM frontal bone
Patterns of chronic inflammatory sinonasal disease
1) infundibular
2) ostiomeatal
3) sinonasal polyposis
infundibular pattern chronic inflammatory sinonasal disease
- MC
- maxillary sinus via obstruction ostium/infundibulum
ostiomeatal unit pattern chronic inflammatory sinonasal disease- pathophys/causes?
- 2nd MC
- blockage middle meatus –> MS, FS, ES
- HTr turbinates, anatomic variants (concha bullosa, middle turbinates curling wrong way (paradoxical), septal deviation.
sinonasal polyposis pattern- pathophys, imaging, key feature/classic description, class associations
- ST nasal polyps & variable degrees of sinus opacification
- key feature: bony remodeling, erosion. “widening infundibula”-must distinguish from expansion via mucocele
- f/f levels 50%
- ass: ASA sensitivity, CF
muocele-pathophys, appearance (change over time), MC sinus
- chronic sinus obstruction (inflamm/tumor) –> circumferential bony expansion
- FS = MC (via obstruction sinus ostia)
- CT: homogenous total opacification
- MR: variable: increasing chronicity, T1+/T2-. In late disease, T2- may be so dark it looks like normally aerated sinus.
- +/- PERIPHERAL enh via inflamed mucosa
complications sinonasal disease
- acute, chronic infection/inflammation
- orbital: subperiosteal abscess, cellulitis, ophthalmic vein thrombosis
- intracranial: spread–> cavernous sinus thrombus, meningitis, abscess (ED, SD, intraparenchymal)
- bony: periostitis, OM –> pott’s puffy tumor
- mucus retention cyst-obstructed small mucosal serous or mutinous glands
antrochoanal polyp-population, syx’s, MC sinus, appearance
- 30-40yo
- syx’s- nasal congestion/obstruction
- benign polyp extending from maxillary sinus –> “widening of ostium” –> nasal cavity
- +/- bone remodeling: smooth enlargement, ie: NO DESTRUCTION
- Rx-complete resection (prevent recurrence)
inverted papilloma-what, classic location, imaging, mx, associated with which cancer?
- rare benign lobulated polypoid epithelial tumor of sinus mucosa
- classic location: lateral wall nasal cavity (middle turbinate)–> impaired maxillary drainage
- img: cerebriform, COMPLETE enhancement (vs mucocele or obstructive secretions). Focal hyperostosis at humor org.
- rx: surgical (recurrent 15%)
- SCC 15-20%
juvenile nasal angiofibroma (JNA)-classic hx
- male teenager w/ nose bleed. obstruction MC in real life
- loc: sphenopalantine foramen
- vascular, intratumor FV, +bony remodel
- presurgical embo internal maxillary, asc pharyngeal artery
“widening of maxillary ostium”
antrochoanal polyp
Enthesioneuroblastoma-pathophys, where, classic look, diagnostic app, who, NM scan?
- malignant NB of olfactory cells. Starts in cribriform plate
- “dumbbell shape w/ waisting at cribriform plate” +Cysts
- dumbell shape-sup growth into skull, inf growth into sinus
- +bone remodeling AND destruction
- v vascular
- diagnostic: intracranial pst cyst
- bimodal age distribution
- ocreotide+
- really fills the nasal cavity –> ext to other structures
cribriform plate
- Sieve-like structure btw anterior cranial loss & nasal cavity, part of the EB.
- Supports olfactory bulb.
SNUC acronym
Sinonasal undifferentiated carcinoma
mc cancer of H/N
SCC
MC location H/N SCC?
maxillary antrum
Imaging H/N SCC-T2 and enh
- T2 dark (v cellular)
- enhances less than other sinus cancers
Sinonasal undifferentiated carcinoma (SNUC)-what, where
- Rare, aggressive, sinonasal nonsquamous cell epithelial or nonepithelial malignant neoplasm of varying histogenesis.
- MONSTER SCC-aggressive, bone destruction, rapid growth, >4cm at presentation, extension
- nasal cavity–> sinuses (ethmoid)
epistaxis-causes. involved locations & mx
- Idiopathic (MC), HHT
- ant septum (MC)= kiesselbach plexus. Compression.
- Pst (5%): sphenopalatine artery (terminal internal maxillary artery). Angiogram, nasal packing, IR
what to watch out for when embolizing sphenopalatine artery
variant anastomosis btw ECA & ophthalmic artery
nasal septal perforation-MC loc & cause
- ant septal cartilaginous area
- causes: surgery (old school Killian submucousal resection), cocaine (3mo), Wegener granulomatosis, syphilis (affects bony septum)
Corresponding ducts: submandicular, parotid, sublingual
SM: Wharton
Parotid: Stenson
SL: Rivinus
Salivary duct most commonly involved in sialolithiasis
Submandibular (Wharton)
odontogenic infection causes. MC scenario?
- Dental or periodontal.
- MC in extracted tooth than abscess of intact tooth
mylohyoid line-clinical significance?
- mylohyoid m –> mylohyoid ridge
- above=anterior mandibular teeth/sublignual space.
- below=2nd & 3rd molars, submandibular space
- dictates spread of infection to SL and SM spaces
MC masticator space mass in adult
odontogenic abscess
Ludwig’s angina- MC cause
- aggressive cellulitis in floor of mouth (submental, SLS, SMS)
- odontogenic infection
Torus palatinus-what, classic history?
- bony exostosis off hard palate midline (normal variant)
- grandma’s dentures won’t stay in
mandibular onsteonecrosis-causes
- prior radiation
- radium
- bisphos rx
ranula
- mucous retention cyst arising from SL gland/space
- typically lateral
“plunging ranula”
ranula extends under mylohyoid m (into SMS)
young adult with new level II neck mass
HPV related SCC w/ necrotic level II LN
lesions of the jaw categories
- non-odontogenic-bony lesions that you see in other bones
- odontogenic- related to teeth
periapical/radicular cyst-what, were, appearance
- acquired cystic degeneration around periodontal ligament from inflammation (dental caries) & less commonly trauma
- well corticated
- <2cm
- apex of non-vital tooth
what is the MC odontogenic cyst
periapical/radicular cyst
dentigerous/follicular cyst
- developemental odontogenic cyst that forms around crown of un-erupted tooth
- ass expansion of mandible, thinning of lingual cortex. inferior alveolar canal displaced inferiorly.
- displaces tooth (typically into condylar regions of mandible or floor of orbit), usually in apical direction.
Keratogenic odontogenic tumor/odontogenic keratocyst-appearance (OKC). Ass syndrome when multiple
- Cystic multiloculated tumor at mandibular body/ramus w/o cortical expansion
- Daughter cysts=multilocular
- grow along length of bone
- bone smoothly scalloped/thinned, can dehisce
- Gorlin Syndrome
Gorlin Syndrome
rare phakomatosis char by multiple odontogenic keratocysts (OKC) & multiple BCCs
Ameloblastoma (adamantinoma of jaw)-what, loc, appearance, hallmark, relation to dentigerous cysts?
- benign but locally aggressive tumor of jaw from odontogenic epithelium
- expansile multicystic (“bubbly”) + solid comps
- usually near 3rd molar (if maxillary, 1st molar)
- usually shown with UNINTERRUPTED tooth
- HM: extensive tooth root absorption
- 5% from dentigerous cysts
Odontoma-what, 2 forms, app.
- tooth hamartoma. “bag of teeth”
- immature form (Lucent).
- mature-sclerotic. radiodense + Lucent rim
- +/- fluffy Cal
“bag of teeth”
Odontoma
What’s in it: parotid space
- parotid gland
- CN 7
- retromandibular vein
relationship of retromandibular vein & facial nerve
RMV medial to FN
What is special about the parotid gland relative to other salivary glands?
Only gland that contains lymph tissue
parotid space pathology
- pleomorphic adenoma/benign mixed tumor
- warthins
- mucoepidermoid carcinoma
- adenoid cystic carcinoma
- lymphoma
- sjogrens
- benign lymphoepithelial dx
- acute parotitis
major & minor salivary glands
- major: parotid, SM, SL
- minor: >100 unnamed
MC major (and minor) salivary gland tumor, MC loc
pleomorphic adenoma/BMT
-parotid –> SL/Sm
Parotid gland division, rel to FN
-line from lateral surf pst belly digastric muscle –> lateral surface mandibular ascending ramus
-superficial lobe-lateral to FN
deep lobe-medial to FN
pleomorphic adenoma/BMT-mc loc, img, malignant potential, rx
- PG (superficial 90%)
- T2+, rim of low signal
- small mal pot
- rx=surgery (can recur of spilled)
Warthin’s tumor-what, who, BL vs UL, nukes study?
- benign cystic tumor of PG (only), 2nd MC
- older male smoker
- BL 15%
- pertechnetate+ (only other PG tumor to do this is parotid oncocytoma) (P for P)
- also thallium and FDG-PET
mucoepidermoid carcinoma-ass?
- mc minor salivary gland malignant tumor
- radiation
MC malignant salivary gland tumor
mucoepidermoid carcinoma
Is malignancy more common in minor or major SGs?
minor
adenoid cystic carcinoma-location, what to know
- malignant SG tumor (minor –> PG)
- perineural spread
parotid lymphoma-causes, app
1˚ or 2˚
- BL=sjogrens
- img: variable (like everywhere else in body)
What disease is ass with parotid lymphoma
Sjogrens (1000x increased risk)
Sjogren’s parotid involvement
- H/N inv
- honeycombed appearance of gland
- new mass=NH MALT type lymphoma
Sjogrens-what, 1˚ vs 2˚, who, img
- AI destruction of SGs & lacrimal glands–> “dry eyes, dry mouth.”
- middle aged-60s F
- 1˚-only SG & LG involvement
- 2˚
benign lymphoepithelial disease-ass, img
- HIV
- BL cystic & solid lesions, diffusely enlarged PGs
- painless (vs parotitis which also enlarge PG)
Causes of parapharyngeal space displacement-ant, medial, pstmedial, lateral
- ant=carotid space
- medial=parotid
- pstmedial-masticator
- lateral-superficial mucosal
Parapharyngeal space contents-clinical significance
- triangular space of fat, +pterygoid v’s & branches CN5
- spread of inf, tumor
- use displacement to localize org of pathology
parapharyngeal space cystic mass
- necrotic LN-mc
- atypical 2nd branchial cleft cyst
carotid space aka
post-styloid, retro-styloid
what’s in it: carotid space
- carotid a
- jugular v
- portions of: CN9-11
- IJ chain LNs
3 classic carotid space tumors
1) paraganglioma
2) schwannoma
3) neurofibroma
Carotid space pathology
- classic tumors- PG, Sch, NF
- infection-necrotizing otitis external
- malignant spread-NP SCC
carotid paragangliomas-types based on location
1) carotid body tumor
2) glomus jugulare
3) glomus vagale
4) glomus tympanicium
Paraganglioma imaging app
- hypervascular (intense tumor blush)
- “Salt & pepper” on MRI from FVs
- Ocreotide NM scan
rule of 10’s in paraganglioma
- ass w/ familiar syndromes
- 10% BL, mal, etc
carotid body glomus-classic img
splaying ICA, ECA at bifurcation
glomus jugular-classic img
- skull base
- destruction middle ear/jugular foramen
glomus vagale
above carotid bifurcation, below jugular foramen
glomus tympanicum
- confined to middle ear
- “overlying cochlear promontory”
- middle ear floor intact
Schwannoma- types in carotid space, img, ass
- CN10 (if higher near skull base: CN 9, 11, 12)
- oval, T2+ hetero (cystic + solid), avidly enhancing (via extravascular leakage and poor venous drainage)
- hypovascular- ie: neg angio
- NF 2 (if multiple)
why do schwannomas have avid enhancement?
Not because of vascularity! Hypovascular lesions but have extravascular leakage + poor venous drainage
Things to consider in resection of carotid space lesions
- distance from skull base: >1 cm=neck dissection
- vascularity-may need pre-embo
- rel to carotid-don’t fuck with big red!
carotid space neurofibroma-img, ass
- T1~/T1+, enh+. Mildly hetero (more homog than schwannoma)
- T2 “target sign”-bright rim, dark middle
- 10% NF-1
paraganglioma vs schwannoma vs neurofibroma
- paraganglioma-peripheral autonomic (SNS, PNS) cells
- neurofibroma-benign peripheral nerve sheath tumor inseparable from normal nerve
neck infection syndromes
- Lemierre’s
- Grisel’s syndrome
bacteria ass w/ lemierre’s disease
fusobacterium necrophorum
grisel’s syndrome
torticollis w/ atlanto-axial joint inflama seen in H/N surgery or RPA
masticator space-m’s, bone, nerve, extent
- muscles of mastication (masseter –> mandible ramus –> temporalis –> pterygoid plate: lateral–> medial pterygoids)
- mandibular ramus
- inferior alveolar nerve (branch of V3)
- extends superior along skull via temporalis m
MC masticator space mass. What to look out for.
- infection
- look for spread via pterygopalatine fossa –> orbital apex & cavernous sinus
masticator space pathology
- infection (MC)
- sarcoma (rhabdomyosarcoma in kids, bone (chondrosarcoma of TMJ)).
- cavernous hemangioma-phleboliths. (venous & lymphatic involve multi compartments/spaces)
- perineural spread-adenoid cystic Ca, melanoma
- nerve sheath tumors-schwannoma or NF of V3 (inferior alveolar n)
what’s most likely to widen neural foramina: schwannoma or perineural spread?
schwannoma
retropharyngeal space
- potential space located pst to pharynx sep by pharyngobasilar fascia
- ant true space- & pst danger space
- ant: ext from skull base –> upper mediastinum (@level of tracheal bifurcation; C6/C7).
- directly lateral are CS and PPS
alar fascia
- directly pst to RPS
- sep RPS from danger space
danger space
ext into mediastinum
-alar f ant, prevertebral f pst
prevertebral space
- anterior comp of perivertebral space in supra hyoid neck, just ant to VB
- bounded ant by prevertebral f, pst by longs Colli m’s
what infections affect the prevertebral space?
spine/disc
role of delayed img in neck inf?
differentiate phlegmon from abscess
mcc retrophargyngeal space infection
tonsillar infection
nodes of rouviere
LNs in lateral retropharyngeal region, regress by age 4
- peds: infection
- adults: mets (SCC, papillary thyroid), lymphoma (won’t be necrotic until treated.)
What are the cervical LN stations
IA, IIB-submental, submandibular IIA, IIB- upper IJ nodes III-middle jugular nodes -IV-inf jugular nodes -VA, VB-pst cervical nodes -VI-pretracheal -VII-superior mediastinal nodes, described by location
Level IA
submental
btw medial margin ant digastric
divisions cervical node stations
- IA, B: hyoid inferiorly, pst margin SM gland
- div by medial margin ant digastric m
- IIA, B: hyoid inferiorly, skull base (pst margin SM gland)
- div by pst margin internal jugular v
- III-
- craniocaudally from hyoid to inferior cricoid cartilage
- posteriorly: margin SCM
- IV
- craniocaudally cc –> clavicle
- AP: carotid a –> SCM (sup), anterior scalene (inf)
- VA-
- CC: skull base –> inf cc
- AP: SCM–> trap
- VB-
- CC: cc–> clav
- AP: anterior scale–> trap
epidemiology of nasopharyngeal SCC
- asian
- bimodal
- 15-30, chinese
- > 40
what worsens prognosis in NP SCC?
PPH involvement (compared to nasal cavity or oropharynx invasion)
Fossa of Rosenmuller
most common location NPP
earliest sign NP SCC
effacement of fat in FOR
which nodes are mc in NP SCC
retropharyngeal
*generally, nodal mets=90%
what percent of patients with NP SCC have skull base invasion?
30%
LOOK AT CLIVUS!
division of larynx
1) supraglottic- epiglottis, valleculae, hypo epiglottic lig preepiglottic fat, false cords, paraglottic space, arytenoid cartilage
2) glottic region- true cords, cricoarytenoid joint, anterior commisure
3) sub glottic region-cricoid ring
laryngocele-what, cause
- fluid filled cyst of laryngeal ventricle (via obstruction)
- forceful blowers (trumpet players, glass blower), 15% obstructed via tumor
vocal cord paralysis
ipsilateral expanded laryngeal ventricle OR laryngeal CA OR chest tumor from recurrent laryngeal n compression
laryngeal cancer-MC type, RFs
85% SCC
-smoking, EtOH, radiation, laryngeal keratosis, HPV, GERD
role of radiologist in laryngeal cancer?
staging-supraglottic, glottic, subglottic, transglottic (crosses laryngeal ventricle)
when can partial laryngectomy be performed in setting of laryngeal CA?
-supraglottic w/o involvement arytenoids or laryngeal Vt
supraglottic laryngeal cancer types
- more aggressive, early LN mets, no hoarseness
1) epiglottic centered: ant, spreads ant across hypo-epiglottic ligament into pre-epiglottic space/fat (which is rich in lymphatics!) and paired vallecula
2) false cord/fold centered
a) pstlat. invades paraglottic space/fat (which comm sup with pre-epiglottic space)
b) aryepiglottic fold mass spreading into paraglottic space & piriform sinus.- paraglottic tumor=T3, “transglottic”, best seen in coronal
glottic laryngeal cancer
- MC and best outcome. Grows slowly. Late metastatic disease
- “progressive & con’t hoarseness”
- ant cord–> spread via ant commissure (typically defined as ST thickening >2mm)
- fixation of cords=T3, best assessed with scope but suspected w/ disease in cricoarytenoid joint
subglottic laryngeal cancer-details, location, surgical
- least common, often small compared to nodal burden (often BL + mediastinal extension)
- ST thickening btw aw & cricoid ring. only reliable sign of cc invsion=tumor on BOTH sides of cartilage (irregular sclerotic cartilage can be N)
- invasion of cricoid=CI to laryngeal conservation surgery)-cc necessary for postoperative stability of vc’s.
adult orbital Ca
- senile
- trochlear (superolat)
- drusen (optic n head, looks like papilledema
- pthisis bulbi-end stage: small globe + Ca
orbital NF
middle age
CN 3, 4, 5 CN
expands SOF
well-defined lobular mass
lymphoma in the eye
- retinal
- conal
- lacrimal
vagal schwannoma vs carotid body tumor
vagal schwannoma-NF 1. Separates ICA, IJV and displace ICA ant
-Carotid body tumor-splays ICA and ECA
mc middle ear tumor
gloms tympanum paraganglioma
-arise from jacobson n at cochlear promontory
