HEAD AND NECK Flashcards
Tonsilitis imaging and complications
tonsilar enlargement, touching in the midline
contrast enhancing without focal fluid
parapharyngeal fat stranding
complications
- peritonsillar abscess
- intratonsillar abscess
- extension to deep spaces
- otitis media
Tonsilitis ddx
SCC
Lymphoma
Tonsillar abscess imaging
central hypoattenuation and rim enhancement
tonsillar tissue surrounding
Peritonsillar abscess imaging
rim enhancing fluid adjacent to enlarged and inflamed tonsil
complications;
- retropharyngeal effusion
- retropharyngeal abscess
- lemierre syndrome (septic thrombophlebitis IJV)
Lemierre syndrome is
thrombophlebitis of the IJC with distant sepsis in the setting of intial oropharyngeal infection (pharyngitis, tonsilllitis, peritonsilar abscess, retropharyngeal abscess).
Retropharyngeal abscess is (and causes)
potentially life threating infection involving the retropharyngeal space.
causes
- complication of primary infection elsewhere such as nasopharync, paranasal sinuses, middle ear
- or oropharyngeal infections, discitis, osteomyelitis, penetrating trauma
Retropharyngeal abscess complications
- posterior extension to prevert, disc/vert, epidural
- lateral extension to carotid and jugular
- anteiror compression airway
- inferior extension to mediastinum
sepsis - grisel syndroime
- lemierre synrome
Retropharyngeral abscess ddx
retropharyngeal cellulitis
retropharyngeal oedema
prevertebral abscess
retropharyngeal haematoma
acute calcific prevertebral tendiintis
pseudothickening
Grisel syndrome is
torticollis of the atlantooaxial joint from inflammatory ligamentous laxity in head and neck infection
Zenker diverticulum is
posterior outpouch of the hypopharynx, proximal to the upper oesophageal sphincter through a weakness in the muscle layer called killian dehiscence (normal cleavage plane between the two parts of the inferior constrictor)
zenkers imaging
midline posterior diverticulum at C5/C6
may be transient
Killian Jameison diverticulum is
an outpouching of mucosa through the killian jamieson space.
located below cricopharyngeus, anteriorly and laterally. typically left sided, can be bilateral. smaller, less frequent and normally asx compared to zenkys
Head and neck SCC pathophysiology
HPV important risk factor, particularly 16, 18, 31
Stronger assoc in some sites, eg. oropharynx
Overexpression of p16 used as surrogate marker
Oral cavity SCC staging
TX cant see
Tis
T1
- <2cm greatest dimension, DOI <5mm
T2
- <2cm DOI 5-10mm OR
- 2-4cm DOI <10mm
T3
- DOI >10mm, or
- tumour >4cm DOI <10mm
T4a moderately advanced
- >4cm DOI >10mm OR
- invades local structures
T4b very advanced
- invades masticator space, pterygoid plates, skull cases and/or encases ICA
Oral cavity SCC ddx
other malig
- lymphoma
- minor salivary gland
- sarcoma
infection
- teeth
- infected rannula
radionecrosis mandible
Cervical node staging
NX
N0
N1
- single ipsilateral node <3cm no ENE
N2a
- single ipsi 3-6cm, no ENE
N2b
- multiple ipsi, <6cm, no ENE
N2c
- bilateral or contralatertal nodes <6cm, no ENE
N3a
- node >6cm, no ENE
N3b
- node with clinically overt ENE
Oral cavity SCC usually in
lower lip, oral tongue, FOM
Oropharyngeal SCC overview
subcatergorised into HPV/P16 positive or negative. P16 associted occurs in younger but responds better to chemoradiotherapy and carry a better prognosis
location; tonsil, base of tongue, soft palate
although can be anywhere
nb; lingual surface epiglottis coiunts as larynx, soft plate nasopharynx
P16 negative oropharyngeal SCC staging
Tx
Tis
T1
- <2cm
T2
- 2-4cm
T3
- > 4cm or
- extension to lingula surface epiglottis
T4a moderate
- larynx
- extrinsix tongue mm
- medial pterygoid
- hard palate
- mandible
T4b very advanced - ICA or any of the following
- lateral pterygoid
- pterygoid plates
- lateral nasopharynx
- skull base
P16 postive oropharyngeal SCC staging
T0
T1
- <2cm
T2
- 2-4 cm
T3
- >4cm OR
- extension to lingual surface epiglottis
T4
- larynx, except lingual epiglottis
- extrinsic mm tongue
- medial pterygoid
- hard palate
- mandible
Hypopharyngeal SCC path
bad for you - worst proggy of all
most commonly at piriform sinus, but can be posterior wall or post cricoid/pharyngooesopahgeal junction
Hypopharynx SCC staging
TX
TIS
T1
- one subsite AND/OR
- <2cm
T2
- extends into adjacent subsite or site AND/OR
- 2-4cm with hemilarynx fixation
T3
- tumour >4cm OR
- clinical fixation hemilarynx OR
- extension to oesophageal mucosa
T4a moderate
- thyroid cartilage
- cricoid cartilage
- hyoid bone
- thyroid gland
- oesophageal muscle
- central compartment soft tissue
T4b
- encases carotid artery OR
- mediastinum/prevertebral
Nasopharyngeal carcinoma path
of squamous origin
some types strongly assoc with EBV
types
- keratinising
- non keratinising
- basaloid squamous
non kerat and basaloid squamous assoc with EBV
NPC imaging
Fossa or rosemuller ionitially effaces
Level 2 and 5 nodes commonly involved
CT
- soft tissue mass fossa of rosenmuller
- smaller confined by pharyngobasilar fascia
- larger can extend in any direction
- heterogenous enhancement
MR
T1 iso to muscle
T2 iso to hyper to muscle, fluid in middle ear
C+ heterogenous prominent. ?perineural invasion
NPC ddx
DDX small
- adenoidal tissue
- nasopharyngeal lymphoma
- low grade or other early primary malig
DDX large
- mets
- adenoid cystic
- plasmacytoma
- fibrosiing pseudotumour
- lymphom
- chordoma
- chondrosarcoma
- meningioma
- JNA
NPC staging
Tx
T0
- EBV positive node
TIS
T1
- confined to nasopharynx OR
- extends to oropharynx or nasal cavity wihtout parapharyngeal invovlement
T2
- extends to paraphryngeal space AND OR
- medial pterygoid, lateral pterygoid, prevertbral muscles
T3
- skull base, cervical vertebra, pterydoid plates, pterygopalatine fossa, paranasal sinuses
T4
- intracranial
- cranial nerves
- hypopharynx
- orbit
- parotid
- soft tissue beyond lateral pterygoid
Larynx SCC staging
T1-3 defined by site
SUUPRAGLOTTIS
T1 limited to one subsite, normal cord mobility
- suprahyoid epi
- aryepiglottic folds
- infrahyoid epiglottis
- false cords
- arytenoids
T2 invades mucosa adjacent area, normal cord mobility
- subsite supraglottis
- glottis
- region outside supraglottis; base of tongue, vallecula, medial wall pyriform sinus
T3 limited to larynx with vocal cord fixation and/or invasion of
- innner cortex thyroid cart
- paraglottic space
- preepiglottic space
- post cricoid area
GLOTTIS
T1 limited to cord with normal mobility
T1a one cord
T1b both cords
T2
extends to supra or subglottis AND/OR
impaired vocal cord mobility
T3
larynx with cord fixation AND/OR
invasion of paraglottix space AND OR
inner cortex thyroid cartilage
SUBGLOTTIS
T1 limited to subglottis
T2 extneds to cords without fixation
T3 limited to larynx with cord fixation AND OR invasion of paraglottis AND OR inner cortex thyroid cart
SAME FOR ALL
T4a
- outer cortex thyroid cart
- cricoid cart
- tissue beyond larynx
T4b
- mediastinum
- prevertebral space
- encases carotid artery
Ranula is a
rare benign acquired cyst at the floor of mouth. result from obstruction of a sublingual gland or adjacent minor gland.
can be simple or plunging
- simple: confined to sublingual space
- plunging: extends to submandibular space, either around posterio edge of mylohyoid or through a deficiency, mylohyoid boutonniere
Ranula imaging
Connection to sublingual space
US
- thin walled, cystic lesions
- can be complex if infected
CT
- thin walled fluid attenuation. can have superimposed infection.
MR
T1 low
T2 high
C+ wall can enhance
DDX
- dermoid/epidermoid
- cystic hygroma
- cervical abscess
- thyroglossal duct cyst
- 2nd branchial cleft cyst
Cricopharyngeal spasm is (and imaging and complications)
may present as a cause of dysphagia
presents as a cricopharyngeal bar at C5/6 on fluoro
complcations
- hypertrophy
- zenkers
Vocal cord paresis causes and imaging
causes
- neck/superior thoracic mass, aortic path, osteophytes
- masses affecting vagus nerve
- iatrogenic injury
- idiopathic
- blunt and penetrating trauma
- congenital anomalies eg meningomyelocele, chiari, hydroceph
imaging
- enlarged piriform sinus
- medialisation aryepiglottic fold
- enlarged laryngeal ventricle
- atrophy thyroarytenoid muscle
- anteromedial deviation arytenoid cartilage
- abducted vocal cordon breath hold, compensatory medial bowing of hte contralateral
Subglottic/tracheal stenosis
Post intubation
Sparing posterior wall
- Relapsing polychondritis (smooth)
- Tracheobronchiopathia osteochondroplastic (nodular)
Involving posterior wall
- amyloid
- wegners
- sarcoid
Relapsing polychondritis is
a rare multisystem disease characterised by recurrent inflammation of the cartilaginous structures in the body. Airways commonly involved
Tracheobronchopathia osteochondroplastica is
a rare idiopathic non neoplastic airway abnormality, with nodular thickening of the cartilage. can be cartilaginous or calcified.
Acute sinusitis imaging
Non specific, can be seen in asx patients
XR
- opacification
CT
- peripehral mucosal thickening
- gas fluid level
- OMC obstruction
- maxillary dentition
MR
T1 mucosa iso, fluid hypo
T2 hyper
C+ mucosa enhances
Complications
- subperiosteal abscess incl orbitla and pott puffy
- dural sinus thrombosis
- meningitis empyema, abscess
Chronic sinusitis imaging
infection over 12 weeks. commonly assoc anatomical variants incl
- concha bullosa
- posterior nasal septal deviations
- uncinate process variations
- paradoxical middle turbinate
- agger nasi cells
- haller cells
sclerotic thickening bone from prolonged mucoperiosteal reaction. intrasinus calc may be present.
five main patterns;
1. OMC: max,. ant eth, front
2. infundibular: isolated ethmoid infundibulum and/or maxillary sinus ostium
3. sphenoethmoidal recess: sphenoid and posterior eth
4. sinonasal polyposis
5. sporadic
Concha bullosa is
pneumatisation of the middle turbinate, commonly assoc with septal deviation
Paradoxical middle turbinate is
inferomedially curved middle turbinate edge with concave surface facing the nasal septum, usually bilat
Agger nasi cells are
most anterior ethmoidal air cells
- anterolateral and inferior to frontal recess
- anterior and above attachment of middle turbinate
- within the lacrimal bone, related laterally to orbit, lacrimal sac, NL duct
Supraorbital cells are
anterior ethmoidal air cells extending posteriorly and superiorly over the orbit from the frontal recess
Sphenoethmoidal air cell/Onodi air cell
Posterior ethmoidal air cell, extends posteriorly to lie superolateral to sphenoid sinus in close prox to ICA and optic nerve. often extends to anterior clinoid process.
Haller cells are
ethmoid air cells lateral to the maxilloethmoidal suture along the inferomedial orbital floor
Fungal sinusitis classification
Non invasive; hypae do not invade mucosa
- allergic fungal
- sinus fungal mycetoma
Invasive; hypae in mucosa and beyond
- acute invasive
- chronic invasive
- granulomatous invasive
Allergic fungal sinusitis imaging and ddx
CT
- sinus opacification
- central serpinginous hyperdense materal
- expangion
- remodelling/thinning
- erosion
MR
- T1 hypo mucosa, variable
T2
- hyperintense mucosa
- low centrally
C+ mucosa enhancement
DDX
sinonasal polyposis
sinus fungal mycetoma
- usually one side, no hyperimmune response
sinonasal mucocele
- same chronic expansive features, no erosions
non hodgkins lymphoma
- homogenous
Paransal sinus mycetoma imaging
CT
- typically single sinus, common is maxillary then sphenoid
- soft tissue with or without calcs
- can have post obstructive/chronic sinusitis features
- no bone erosions
MR
T1 low
T2 low
C+ mucosa might enhance
DDX
allergic fungal sinusitis
chronic invasive fungal sinusitis
- bone erosion
paranasal sinus mucocele
sinonasal inverted papilloma
Acute invasive fungal sinusitis is
most aggressive form fungal sinus disease. seen mostly in immunocompromised patients. aspergillus in neutropaenia and zygomycetes in diabetes
Acute invasive fungal sinusitis imaging
CT
- NO internal hyperdensity, unlike chronic
- mucosal thickening
- opacification of the sinus
- bone destruction
- fat stranding outside sinus perimeter, including periantral fat stranding
MR
T1 intermediate to low
T2 fungal mass low to intermediate
- black turbinate sign; non enhancement nasal turbinates from invasion/necrosis
C+ absent mucosal enhancement suggests necrosis, invasion
Assess in particular for
- stranding of the periantral fat - intraorbital, masticator, pterygopalaitine
- subtle enhancement
- leptomeningeal enhancement
- intracranial granulomas
- cavernous sinus thrombosis
- carotid pseudoaneurysm
- cerebrtits/abscess
Chronic invasive fungal sinusitis imaging
more than 12 weeks
CT
- homogenous opacification iso to hyper
- lack of expansion
- mottled bone destruction
- focal bone erosion and extrasinus component
- sclerotic change
MR
- iso to hypo
- usually marked hypo
Granulomatous invasive fungal sinusitis is
a form of invasive fungal sinusitis
large expansive mass with bone destruction and local invasion.
CT
bone destruction
hyperdense
homogenous enhancement
MR
t2 dark
DDX: malignant lesions incl
- sinonasal SCC
- sinonasal adenoid cystic
- adenocaricnoma
- SNUC
- lymphoma
- melanoma
- esthesioneuroblastoma
Granulomatosis with polyangitis is
also known as Wegeners, a multisysem necrotising non caseating granulomatous vasculitis affecting small to medium sized arteries/capilleries
Granulomatosis with polyangitis upper resp features
sinusitis/mastoiditis/otitis
sclerosing oteitis of the nasal cavity
sinonasal mucosal ulcers
lacrimal gland involvement
nasal septal perf/deviation
subglottic stenosis
Sinonasal polyposis is
the presence of multiple benign polyps in the nasal cavity and paranasal sinuses
Sinonasal polyposis imaging and grading
extensive polyps occupying the nasal cavity and sinuses
usually hypodense but can be hyper
assoc local benign bone remodelling or erosion
- mucoceles whole sinus expanded
opacified ethmoid sinuses with convex lateral walls and air fluid levels
concurrent infection can be present
Meltzer
0 - no polyps
1 - single in middle meatus
2 - multiple in middle meatus
3 - extending beyond middle meatus
4 - nasal cavity obstruction
Antrochoanal polyps are
solitary sinonasal polyps that arise within the maxillary sinus. pass through the ostium to the nasapharynx and nasal cavity. can occur elsewhere less commonly. present with sinonasal obstruction
Antrochoanal polyp imaging
XR
unilateral opac
can see nasopharyngeal mass
CT
defined mass with mucin density
widening of the maxially ostium extending to the nasopharynx
no bony destruction, but smooth enlargement of the sinus
can be dessicated and high density
MR
T1 intermediate to low
T2 high homogenous
C+ peripehral
Inverted papillomas are
type of Schneiderian papilloma representing an uncommon non cancerous sinonasal tumour most commonly seen in middle aged men. can undergo malignant transformation. classically have convoluted cerebriform on T2 and contrast imaging
Inverted papilloma imaging
CT
non spec
soft tissue density masswith enhancement
location; most commonly lateral wall nasal cavity
can have intralesional calc representing residual bone fragments
MR
distinctive convoluted cerebriform pattern on T2 and post con T1
Juvenile nasal angiofibroma is
a rare benign but locally aggressive vascular tumour of young men. vivdly enhancing soft tissue mass centred onthe sphenopalatine foramen. flow voids/s&p MR.
Juvenile nasal angiofibroma imaging
CT
nasopharyngeal mass
lobulated soft tissue mass cnetred on sphenopalatine fossa
anterior bowing of the posterior maxillary wall
marked enhancement
Angio
to see supply
MR
T1 intermediate
T2 heterogenous, flow voids
C+ prominent
Juvenile nasal angiofibroma staging
1a nasal cavity/nasopharynx
1b exension to sinus
2a into pterygomaxillary fossa
2b fills pterygomaxillary fossa bowing psterior wall max antrum anterior or into orbit
2c beyond pterygomax fossa into infratemporal fossa
3 intracranial exnteion
Tornwaldt cyst is
a common incidental benign nasopharyngeal mucosal cyst
Tornwaldt cyst imaging
well cricumscribed
rounded
immediately deep to mucosa
bw/anterior to longus colli muscles
ct
low density
non enhancing
can be hyperattenuating
mr
t1 variable due to protein
t2 high
C+ no enhancement
Paranasal sinus mucocele is
complate opacification of a sinus by mucus, often with bony expansion due to obstruction. clinical presentation depending on direction of expansion and presence of infection
Paranasal sinus mucocele imaging
cant have air in the sinus
CT
complete opacification
margins expanded and thinned
may have bony resorption
attenuation is variable
MR
signal intensity highly variable depdning on water/protein/mucus
T1 low most common
T2 high most common
C+ if present than peripheral
DWI variable
Sinonasal undifferentiated carcinoma is
a rare and highly aggressive neoplasm arising from the paranasal sinuses. Mostly ethmoid and superior nasal cavity.
Sinonasal undifferentiated carcinoma imaging
Ethmoid/superior nasal cavity
Bone destruction
CT: enhances to variable degree
MR
T1 iso to muslce
T2 iso to hyper to muscle
C+ heterogenous
Olfactory neuroblastoma/esthesioneuroblastoma is
a tumour arising from the basal layer of the olfactory epithelium in the superior recess of the nasal cavity.
Usually presents as a soft tissue mass in the anterior/middle ethmoidal cells extending through the cribriform plate to the anterior cranial fossa.
Olfactory neuroblastoma/esthesioneuroblastoma imaging
Slow growing
Begin at superior olfactory recess
Involve ant/mid ethmoidal cells
often form dumbell with waist at cribriform
CT
soft tissue
can have focal calcs
homogenous enhancement
bone can be remodelled rather than destroyed
MR
T1 heterogenous
T2 heterogenous
C+ variable, usually bright
Peritumural cysts at intracranial aspect
Olfactory neuroblastoma/esthesioneuroblastoma ddx
Olfactory neuroepithelioma
Olfactory groove meningioma
Sinonasal carcinoma
- lack peritumoural cysts
Rhabdo
NPC
- more posterior, older
Olfactory neuroblastoma/esthesioneuroblastoma stagign
Kadish
a: nasal cavity
b: nasal cavity and paranasal sinuses
c: extends beyond
- BOS
- intracranial
- orbit
- mets
Sinonasal adenocarcinomas are
primary tumours of the sinonasal region with glandular differentiation. Classified into salivery and non salivery, NS into intestinal and non intestinal
Sinonasal adenocarcinoma imaging
Ill defined, heterogenously enhancing
Intestinal tends to be ethmoid/nasal cavity
Non intenstinal maxillary
CT
aggressive bone destruction
heterogenous enhancement
MR
intermedialte T1 and T2
possible haemorrhagic foci
heterogenous enahcnement
Paranasal sinus osteoma imaging
Location
- mostly frontal
- tehn ehtmoid, max
- rare in sphenoid
Can be ivory, mature or mixed
Assoc with Gardners
CT
well circumscribed mass of variable density, ranging from v dense to more ground glassy
MR
low intensit all sequences
ddx
- FD
- other osteogenic - osteoblastoma, osteosarcoma, cementoossifying fibroma
Encephalocoeles are
a form of neural tube defect where brain and meninges herniate through a cranial defect. can have a stalk in 15% to brainbut no fluid tract distinguishing from nasal encephaloceole
mass, without pulsations or increased size with valsalva or compression of ipsilateral jugular vein
Sinonasal mucosal melanoma is
a rare subtype of melanoma. typically expansile mass centred within the nasal cavity, or less commonely, the paranasal sinuses.
Sinonasal mucosal melanoma imaging
CT
polypoid or mass like
bone remodelling or erosion
strongly enhancing
MR
T1 homogenoeus,can be high
T2 low
C+ moderate enhancement
Sinonasal lymphoma is
involvment of hte nasal cav/paranasial sinuses with lymphoma. most commonly nasal cavity and maxillary sinus. generally t cell
Sinonasal lymohoma imaging
can be discrete or diffusely infiltrating
CT
soft tissue attenuating
can have bone destruction
MR
T1 intermediate
T2 hypointense
C+ typically homogenous
Rhinoscleroma is
a chronic granulomatous infection involving the upper respiratory tract due to Klebsiella.
Rhinoscleroma imaging
Nasal mass with the following features
CT
bilateral or unilateral
expansile
homogenous
hyperdense and non enhancing
can extend through nares and into sinuses
no bone destruction
MR
T1 mild to marked high signal
T2 hyper with hypointense foci of fibrosis
C+ inhomogenous
DWI restriction with low ADC
DDX
Granulomatous disease
Lymphoma and sinonasal carcinoma
Head and neck rhabdomyosarcoma general path
large proportion of all rhabdos and most common soft tissue sarcoma in the head and neck
usually embryonal and in children
can be orbital, parameningeal, middle ear or other
Head and neck rhabdomyosarcoma imaging
MR
T1 iso to hyper
T2 hyper
C+ marked enhancement, usually heterogenous due to haemorrhage/necrosis
Can have diffuse restriction
Le fort 1
horizontal maxillary fracture
floating teeth
passes through
- alveolar ridge
- lateral nose
- inferior wall maxillary sinus
- pterygoid plates
Le fort 2
pyramidal fracture, teeth at base and nasofrontal suture at apex
floating maxilla
fracture arch passes through
- posterior alveolar ridge
- lateral wall maxillary sinus
- inferior orbital rim
- nasal bone
- pterygoid plate
Le fort 3
craniofacial disjunction
floating face
transverse line through
- nasofrontal suture
- maxillofrontal suture
- orbital wall
- zygomatic arch/zygomaticofrontal suture
- pterygoid plates
Le fort practical points
Pterygoid plates
Type 1 - anterolateral margin nasal fossa
Type 2 - inferior orbital rim
Type 3 - zygomatic arch
Nasofrontal suture means type 2 or 3
Zygomaticomaxillary complex fractures comprise fractures of the
zygomatic arch
inferior orbital rim, anterior/posterior maxillary sinus walls
lateral orbital rim
Imaging
- fracture of the arch and/or temporozygomatic suture diastasis
- fracture of the inferior orbitall rim, anterior and posterior maxillary sinus wall and/or zygomaticomaxillary suture
- fracture of the lateral orbital rim and/or diastasis of the frontozygomatic suture
Nasoorbitoethmoid (NOE) complex fractures are
fractures involving the central upper midface. high impact to nose transmitted through ethmoid
comminution of both medial maxillary buttresses results in a pattern of fractures involving the nasal bones, septum, ethmoid sinuses and medial orbital walls
associated injuries
- telecanthus
- nasolacrimal duct
- orbital injuries
- CSF rhinorrhea
- epiphora
Sialadenitis is, causes and associ
inflammation of the salivery glands
causes
- acute bacteria (staph and strep v)
- stones
- dehydration, immunosuppression, iatrogenic, cancer
assoc
- sjogren
- mikulicz
- post radiation
- i-131
- HIV/IRIS
Sialadenitis imaging
US
- enlarged
- hypoechoic
- hyperaemic
- chronic; atrophic, hypoechoic, irregular margins
CT
- enlarged, abnormal attenuation, indistinct margin, contrast enhancement
- stranding
- silated duct
- enlarged nodes
- abscess
MR
- Acute T1 low, T2 high
- Chronic T1 inhomgenous low, T2 low
Sialolithiasis location
almost always submandibvular wharton duct
then parotid duct
Pleomorphic adenoma is
a benign mixed tumour, occuring most commonly in the salivery glands. most common SG tumour.
well circumscribed mass commonly in the parotid,hypoechoic on us and t2 bright with homogeneous enhancement
small risk of malig transformation to carcinoma ex pleomorphic adenoma
Pleomorphic adenoma location
80% parotid
10% SMG
minor 6%
sublingual 1%
also commonly found in lacrimal gland
Pleomorphic adenoma imaging
rounded mass with bosselated or polylobulated borders
commonly superficial lobe parotid
can be deep lobe, extraparotid extendinfg to prestyloid parapahrynfeal space and stylomandibular tunnel
US
hypoechoic posterior acoustic enhancement
CT
homogeneous attenuation
prominent enhancement
larger can be heterogenous
M
T1 low
T2 high+, decreased signal rim
C+ homogenous enhancement
Pleomorphic adenoma ddx
When in parotid;
- warthin
- mucoepidermoid
- myoepithelioma
- adenoid cystic carc
- mets
- lymphoma
- facial schwannoma
Warthin tumours are
benign tumours of the salivary glands
most common from the parotid tail
can be bilateral/multifocal
second most common after pleomorphic
Warthin tumour imaging
commonly parotid tail at the mandibular angle
sometimes elsewhere
undergo cystic change more than any other salivary gland tumour
US
ovoid
well defined
multiple irregular spongelike areas
larger; more cysts
hypervasc
CT
well defined heterogenous solid cystic within the superficial parotid
no calc
moderate enhancement
mural nodule
common b/l
MR
well def and bilateral
T1 low to intermediate, cysts have cholesterol and can be high
T2 heterogenous and variable signal
C+ solid parts enhance
Salivary gland tumours useful tips
benignity proportional to size
- parotid commonly benign, SMG 50/50, minor mostly malig
SUBTYPES
Benign: epithelial
- pleomorphic adenoma
- warthin
- intraductal papilloma
- oncocytoma
- myoepithelioma
Benign: non epithelial
- haemangioma
- lymphangioma
- lipoma
Malignant
- mucoepidermoid
- Adenoid cystic carc
- myoepithelioma
- adenocarc
- acinic cell carc
- squamous
- carcinoma ex pleomorphic adenoma
- salivary duct carcinoma
- metastases (cut SCC, melanoma, seminoa)
- lymphoma
Mucoepidermoid carcinoma of salivary glands are
most common malignant primary of the parotid. also occur at hard palate commonly
Mucoepidermoid carcinoma of salivary glands imaging
US
hypoechoic
well circum
CT
well circum
usually cystic components
solid bits enhance
calcs sometimes seen
look like PMA
higher grade; infiltrative
MR
low grade (like PMA)
- T1 low to intermediate
- T2 intermediate to high, cystic high
- C+ heterogenous enhancement solid
high grade
- lower T2, poorly defined margins and infrequent cystic areas
- assess for perineural spread
Adenoid cystic carcinomas are
second most common malig ofthe minor salivary glands behind mucoepidermoid
locally aggressive with propensity for perineural spread
Adenoid cystic carcinoma imaging
Low grade; well defined
High grade; infiltrative
Frequently assoc with perineural spread
MR
T1 hypo to iso
T2 hyper, higher grade more hypointense
C+ homogeneous
HIV assoc salivary gland disease is
a condition of lymphatic infiltration of the salivary glands, particularly the parotids
HIV assoc salivary gland disease imaging
US
numerous cysts/hypoechoic spaces without posterior enhancement
straight up cysts for real
CT/MRI
bilateral salivary enlargement with intraglandular cystic and solid masses
increased lymph nodes\
main jenny diffy would probably be sjogren they get multicystic appreance f the parotids, can be salivary glands
Supernumery teeth assoc
Cleidocranial dysostosis
Gardner syndrome
Cleft palate
Mesiodens is
a supernumery tooth in the palatal midline between the two maxillary central incisors
Mesiodens complications
impaction or delayed eruption central incisors
widening of incisor gap
abnormal poistion or curve of the incisors
resorption incisors
dentigerous cysts
nasal cavity eruption
Periapical radiolucency ddx
Apical periodonitis (granuloma/abscess)
Periapical cyst
Cemento-osseous dysplasia
Tumours
Trauma
Residual cyst
Periapical cysts are
also known as radicular cysts, most common cystic lesions. result from infection.
generally small <1cm, round, pear shaped, thin rim of cortical bone
usually restoration/cary of the adjacent tooth
Periapical granuloma is
a mass like region of granulation tissue in relation to teeth infection
tend to be higher attenuating than periapical cysts
Periapical abscess is
acute infection of the periapical tissue around the root of the tooth
Periapical abscess imaging and complications
Imaging
- well defined lucency
- adjacent caries
- adjacent empty socket
Complications
- OM
- CNS infection
- ludwig angina
- deep space infection
- sinusitis
TMJ dislocation typwa
abnormaly displacement with loss of normal articulation with the glenoid fossa
can be
- anterior
- cranial
- posterior
anterior
- most common
- exaggerted and often recurrent normal anterior translocation of the condyule from the fossa
cranial
- rare, from upward force directing the condyle through the glenoid fossa into the middle cranial fossa
posterior
- rare
TMJ anatomy quick recap
synovial joint
mandibular condyle and temporal mandibular fossa/glenoid fossa
also anterior articulating eminence
articular disc - anterior band, intermediate band, posterior band
posterior band connects to bilaminar cartilage which connects to posterior capsule
lateral pterygoid to anterior capsule
TMJ normal appearance
disc is low signal all sequences, biconcave, located between the condyle and temporal bone with the posterior band at the 12 oclock position and the angle between the PB posterior limit and the vertical condyle <10deg
can be anteriorly displaced in asx patients, only about 30% sx
TMJ dysfunction imaging
Direct signs
- anterior disc displacement; displaced in closed mouth, can reduce when open (recapture) or not
- posterior disc displacement; posterior band displcaed posteriorly beyond 1oclock
- stuck disc; fails to displace in open or closed mouth position, fixed to temporal bone
Indirect
- large effusion
- rupture of retrodiscal layers
- thickening of the lateral pterygoid muscle attachment
- OA changes
Mandibular osteoradionecrosis is
osteonecrosis following radiation therapy due to its superficial position.
imaging
- cortical destruction
- sequestration
- absence of a soft tissue mass
Medication related osteonecrosis of the jaw is (drugs and imaging)
bony destruction of the jaw with exposed bone present for greater than 8 weeks in the presence of antiresorptive/antiangiogenic medication and absence of radiotherapy
can get it with (OP, malig, immunosupp)
- bisphosphanates
- mabs
- tyrosine kinase inhibs
- VEGF inhibs
- mTOR inhibs
imaging
- lucent or mixed lesion
- sequestrum
- periosteal prolif/rxn
Nasolabial cysts are
rare non odontogenic soft tissue developmental cysts occurring inferior to the nasal alar region
Nasolabial cyst imaging
simple cyst in the nasolabial region separated from bony structures and teeth
Incisive canal cysts are
developmental non neoplastic cysts arising from degenration of the nasopalatine ducts. develop in the midline anterior maxilla.
Dentigerous cysts are
slow growing, benign, non inflammatory odontogenic cysts.
present as a well defined unilocular radiolucency surrounding the crown of an unerupted tooth within the mandible
assoc with
- mucopolysacc
- basal cell naeuvys syndrome
Dentigerous cyst imaging
cystic expansile pericoronal lesion containing the crown of an impacted tooth
tend toi attach to cementoenaml junction
thin regular sclerotic margin
variable size
MR
t1 low
T2 high
no enhancement
Stafne cyst is
a cortical defect near the angle of the mandible below the mandibular canal. can be filled by SMG or fat.
Temporomandibular joint inflammation causes
RA
Ank spond
CPPD
Gout
Psoriatic arthritis
SLE
JIA
Odontogenic keratocyst (OKC) are
rare, benign cystic lesions involving the mandible or maxilla.
typically appear as expansile solitary unilocular lesion in the posterior mandible
assoc
- basal cell naecus (or Gorlin Goltz)
- margans
- noonan
Odontogenic keratocyst imaging
solitary radiolucent unilocular expansile
smooth corticated borders
typically posterior mandible
large enough; resorp roots of tooth
can sometimes be septated
MR
T1 high
T2 heterogenous
DWI restricts
C+ peripheral enhancment no nodular component
Ameloblastoma is
a locally aggressive benign tumour arising from the mandible or sometimes maxilla
Ameloblastoma imaging
90% multicystic, soap bubble lesions
well demarcated borders no matrix
resorption of adjacent teeth
can be unicystic and pericoronal, similar to dentigerous, OKC, ameloblastic fibromas
MR
mixed solid and cystic pattern
thick irregular wall with enhancing papillary projections
Odontomas are
most common odontogenic tumours of themmandible
assoc with gardner syndrome
Odontoma imaging
initially lucent, develops small calcs, eventually coalesce to form a radiodense lesion with a lucent rim
Aberrant internal carotid artery is
a variant of ICA that represents a collateral pathway resulting from involution of the normal cervical portion of the ICA
enlargement of the small collaterals that pass lateral to the cochlear promotory
- inferior tympanic aa (ECA)
- caroticotympanic aa (petrous ICA)
vessels rejoin the petrous segment.
May present with pulsatile tinnitus
Aberrant ICA imaging and ddx
enlarged inferior tympanic canaliculus
retrotympanic mass
absent carotid plate
absent or hypoplastic vertical segment of the carotid canal
ddx
- lateralised ICA: protrudes into the anterior mesotympanum but dosnt course across the cochlear promotory or enlarge the inferior tympanic canaliculus
- petrous ICA aneurysm
- glomus tympanicum
- glomus jugulare
- dehiscent jugular bulb
Temporal bone fracture breakdown and complications
Fracture orientation
- longitudinal
- horizontal
- mixed
Otic capsule involvement, predicts;
- faical nerve involvement
-CSF leak
- sensorineural hearing loss
- epidural/SA haematoma
Complications
- facial nerve palsy
- ossicular chain disruption
- otic capsule involvement
- CSG leak
- meningitis
- post traumatic cholesteatoma
- perilymphatic fistula
Acute otomastoiditis imaging
CT
- opacification
- erosion of septa
- erosion of lateral wall or sigmoid plate
- soft tissue abscess
- petrous apicitis
- cerebral abscess or dural venous sinus thrombosis
MR
- opacification
T1 low
T2 high
DWI possible
C+ mucosal enhancement typical
Bezold abscess is
complication of otomastoiditis
deep to scm
Citelli abscess is
complication of otomastoiditis
abscess in digastric triangle
(or OM of occipital bone, same name)
Acute otomastoiditis complications
subperiosteal abscess
bezold abscess
citelli abscess
labyrinthitis
petyrous apicitis
intracranial extension
facial nerve dysfunction
thrombosis of mastoid emissary vein (griesinger sign)
Petrous apicitis clinical presentation
Otomastoiditis symptoms and
- deep facial pain due to meckels cave inflammation
- abducens nerve palsy (gradenigo syndrome) inflammation of dorellos canal
Cholesteatoma general types
Congenital
Acquired
- priamry (no hx of infection)
- secondary
- pars flaccida
- pars tensa
External ear canal
Mural cholesteatoma
Petrous apex
Cholesteatoma important features to report
Erosions - scutum, ossicles, lateral semicircular
Dehiscence - facial nerve canal, tegment tympani
Integrity of - epitympanum, aditus ad antrum, oval and round window
Presence in sinus tympani
Sinus tympani is
small recess in posterior mesotympanum medial to pyramidal eminence and stapedius muscle origin
Congenital cholesteatoma imaging
Characteristically in the petrous apex
MR
T1 low
T2 high
FLAIR can have partial attenuation (unlike cholesterol granuloma)
C+ non enhancing, or maybe margins
DWI restricted diffusion
Acquired cholesteatoma path and complications
typically middle ear, result from chronic infection
four hypothesis
- invagination/negative pressure, eustachian tube dysfx and membrane retraction
- invasion migration
- basal cell hyperplasia
- metaplasia
complications
- labyrinthine fistula
- cochlear fistula
- labyrinthitis
- facial nerve dysfx
- extension through IAM, middle cranial fossa, petrous apex
Acquired cholesteatoma imaging
Depends on part of the TM it arises from;
Pars flaccida
- superior extension; expands into prussak space, eroding the scutum, displacing the ossicles medially
- inferior extension; less common
Pars tensa
- posterosuperior; extends medial to the incus and displaces the ossicles laterally
- anteiror and inferior
MR
T1 low
T2 high
C+ none
DWI restricts
Acquired cholesteatoma ddx
Cholesterol granuloma
- high t1
- no enhancement
- no restriction
Mucoid impaction
Glomus tympanicum
Facial nerve schwannoma
Post op:
Recurrence
- low t1
Granulation tissue
- intermediate t1
- enhancement
- low DWI
Scarring
- low T1/T2
- low DWI
External auditory canal atresia imaging and associations
Assoc
- crouzon
- treacher collins
- goldenhar
- pierre robin
CT mention
- middle ear cavity volume
- ossicles (often involved)
- inner ear structure, both windows need to be there
- course of the ICA and jugular bulb
- course of the facial nerve
Dehiscent jugular bulb is
absent sigmoid plate with a high riding jugular bulb. cause of pulsatile tinnitus and retrotympanic vascular mass.
Semicircular canal dehiscence clinical
Superior
- vestibular and visual symptoms
- tullio phenomenom - vertigo and nystagmus from loud noises
- auditory dysfunciton
Posterior
- mostly hearing
Large endolymphatic duct and sac syndrome imaging and associations
Assoc
- pendred syndrome
- vestibular anomalies
- cochlear anomalies
- semicircular canal anomalies
Imaging
- enlarged vestibular aqueduct >1.5mm at the midpoint (valvassori)
- opercular width >2mm (Cincinnati)
Petrous apex mucocele iamging
CT
smooth expansile lesion
MR
T1 low to intermediate
T2 high
C+ no central, can have peripehral
DWI no restriction
DDX
Cholesterol granuloma
- should be high on T1
Labyrinthitis ossificans is
ossification of the membranous labyrinth as a response to insult, commonly infection but also surgery or trauma, autoimmune or sickle cell
Labyrinthitis ossificans imaging
Scala tympani of the basal turn of the cochlea is the most commonly affected site
CT
- mild: hazy increased density in the fluid spaces
- moderate: focal areas of bony encroachments
- severe: complete obliteration
MR
loss of normal high fluid signal
Otosclerosis is
a primary osteodystrophy of the otic capsule. Can have conductive, sensorineural or mixed hearing loss. Commonly bilateral.
Two phases - otospongiosis and otosclerosis
Two subtypes - fenesteral and retrofenestral
Fenestral (stapedial)
- involves the oval window and stapes footplate
- hearing loss is conductive due to fixation
Retrofenestral (cochlear)
- cochlear involvement and demineralisation of the cochlear capsule
- hearing loss is sensorineural
Otosclerosis imaging
Fenestral
- just anterior to the oval window
- fissula ante fenestram
- bony overgrowth can cause fixation of the stapes
Retrofenestral
- second most common
- invovlement of the round window niche
- bone surrounding cochlea, can be focal or circumfrential
Otospongiotic phase
- demineralisation and spongy bone cause lucency
Otosclerotic
- region increases in attenuation
DDX
- OI
- Pagets
- osteoradionecrosis
Otosclerosis grading
Symons and fanning
Grade 1
- solely fenestral
Grade 2
- patchy localised cochlear disease
a) basal cochlear turn
b) middle/apical turns
c) both basal and middle/apical turns
Grade 3
- diffuse confluent cochlear invovlement of the otic capsule
Cholesterol granuloma is
sometimes called a choclate cyst of the ear or blue domed cyst
special type of middle ear granulation tissue which is particularly prone to bleeding and frequent cause of haemotympancum
most common cystic lesion of the petrous apex
Choleterol granuloma imaging
CT
- expansile well marginated lesion with thinned overlying bone
- can look more aggressive/erosive at the petrous apex, less so in the middle ear
MR
T1
- high due to cholesterol component and methaemoglobin +/- haemosiderin rim
T2
- central high signal
- peripheral low signal rim
FLAIR
- no attenuation
C+ can hve faint peripheral enhancement
DWI
- no restriction
Cholesterol granuloma ddx
Asymmetric marrow/pneumatisation
Middle ear effusion
Cholesteatoma
Base of skull tumours
Hydrated mucocele
- can be identical
Thrombosed ICA aneurysm
- usually more complex
- can have a residual flow signal
Cochlear implant assessment
Modified stenvers view
- positions it in the plane of the sueprior semicircular canal
- cochleostomy in vertical plane with superior semicircular canal
- electrodes should be medial to stomy
Inner ear malformations classification
Sennaroglu
- Complete labyrinthe aplasia (Michels)
1 ) with hypoplastic petrous
b) without otic capsule
c) with otic capsule - Rudimentary otocyst
- round or ovoid cystic space in place of the inner ear
- IAC absent
- carotid canal absent
- SCC may be present rudimentarily - Cochlear aplasia
a) normal vestibule
b) dilated vestibule - Common cavity
- absent normal diff between cochlea and vestibule - Cochlear hypoplasia
a) bud like
b) cystic hypoplastic
c) cochlea with less than 2 turns
d) cochlea with hypoplastic middle and apical turns - Incomplete paritition of the cochlea - defects involving the modiolus and interscalar septa
a) type 1 cystic cohleovestibular anomaly
b) type 2 part of mondini (if enlarged vestibular aqueduct)
c) type 3 X linked deafness - enlarged vestibular aqueduct
- Cochlear aperture abnormalities
Persistent stapedial artery is
an abnormal small vessel arising form the petrous portion of the intenral carotid artery and crossing through the middle ear
results from failure of regressin of the embryonic stapedial artery
imaging
- small canaliculus originating from the petrous segment of the ICA
- linear segment of soft tissue density corssing over the cochlear promontory
- enlarged facial nerve canal or separate canal
- aplastic or hypoplastic foramen spinosum
Necrotising otitis externa is
severe invasive infection of the EAC which can raidly spread.
typically diabetics, immunosuppressed, elderly
pseudomonas 98%
Intralabyrinthine haemorrhage
this is a thing
intrinsic high t1 from methaemoglobin
Ramsay hunt syndrome is and imaging
shingles of the facial nerve, reactiation of VZV
otalgia, facial nerve palsy, vesicular eruption invovling the tongue, pinna, EAC
identical to Bells with increased enhancement of the facial nerve
Normal facial nerve enhancement
typical sites
- fundal canalicular
- anterior gen
- posterior genu
rarely other places but shouldnt have it in the meatal segment or extracranial
Endolymphatic sac tumours are and imaging
locally invasive tumours of the endolymphatic sac/duct. assoc with von hippel lindau
almost always arise from the vestibular aqueduct involving the sac or duct
CT
infiltrative or moth eaten erosion
central calcific spiculation and posterior rim calcification
intense enhancement
MR
T1 foci of hyper
C+ heterogenous
T2 heterogenous
Keratosis obturns is and imaging
rare EAC disease characterised by expansion of the EAC by a plug of desquamated keratin
CT
well defined soft tissue mass within the EAC
diffusely enlarged without erosion
Branchial cleft anomalies
comprise a spectrum of congenital defects that occur in the head and neck
result from persistence of branchial cleft or pouch resulting in a cevical anomaly located along the anterior border of the sternocleidomastoid muscle from the tragus of the ear to the clavicle
encompass cysts, fistulas and sinuses
Types/locations of branchial cleft anomalies
First
- above the level of the mandible near the EAC within or close to the parotid gland
Second
- between the mandible angle and the carotid bifurcation
- deeper than the platysma and superficial layer of deep cervical fascia
- between pharyngeal wall to skin, laterally and inferiorly between ICA and ECA
- extension between the ICA and ECA above bifurcation “notch/tail/beak sign”
- most common 95%, most common of these is at the angle of the mandible
Third
- infrahyoid neck
- posterior to the common or internal carotid, between the hypoglossal nerve below and glossopharyngeal nerve above
- most lie in the posterior cervical space posterior to the sternocleidomastoid
- if a sinus can drain to pyriform sinus
Fourth
- infrahyoid neck usually adjacent to the thyroid gland
- can be hard to tell from a third
- parallel the course of the recurrent laryngeal nerve
- more common on the left
- usually form a sinus with apex at the pyriform sinus, like the third, but extend inferiorly to reach anterior left upper thyroid lobe
Thyroglossal duct cyst is and imaging
congenital neck cyst/mass
typically midline, can be anywhere from foramen caecum to thyroid gland, though typically infrahyoid
minimally complex on US unless infection
may have slight rim enhancement
can rarely have a papillary carcinoma assoc
generally within 2cm of midline
usually deep to strap muscles, can be embedded
MR
T1 variable
T2 typically high
C+ none if uncomplicated
Oesophageal diverticula classification
can be false or true
- true: all layers
- false: herniating through muscle layer
Can be traction or pulsion
- traction: secondary to pulling forces on outer oesophagus
- pulsion: occurs secondary to increased intraluminal pressure
Can be upper, middle or lower
Upper
- Zenkers
- Killian Jamieson
Middle
- traction diverticula (2nd to fibrosis/inflammation/scarring)
- pulsion: secondary to pressure
Lower
- epiphrenic
Zenkers diverticulum is
a posterior outpouching of the hypopharynx just proximal to the upper oesophageal sphincter through a weakness in the muscle layer called Killian dehiscence/killian triangle
Killiam Jameison diverticulum is
false diverticulum of the upper oesophagus through the killian jameison sapce. just below circopharyngeus, anteriorly and laterally
Epiphrenic diverticulum are
pulsion diverticula of the lower oesophagus just above the lower oesophageal sphincter more frequently at the right posterolateral wall
Thymic cysts are
cysts that occur within or arise from the thymus
can be acquired on congenital
congenital
- arise from a patent thymopharyngeal duct
- contain thymic tyissue
- often unilocular
- can be cervical
aquired
- secondary to thoracotomy or following treatment
- assoc with thymic tumours
- cann be uni or multilocular
can be cervical or mediastinal
Carotidynia is
also known as fay syndrome, characterised by neck pain in the region of the carotid bifurcation
aetiology is unclear. elevated inflammatory markjers.
typically about the bifurcation
mild narrowing of the lumen
eccentric wall thickening, enhancement, fat stranding
king kong carotid
ddx
dissection
vasculitidies
trigeminal nerve denervation
muscles of mastication
mylohyoid
anterior digastric
tensor tympani/tensor palatini
hypoglossal nerve denervation
unilateral tongue atrophy, except for palatoglossus (X)
Castleman disease is
an uncommon benign b cell lymphoproliferative condition
can be unicentric or multicentric (usually HIV)
Kimura disease is
a rare benign inflammatory disease manifestly as enlargement of the cervical nodes and salivary glands
high attenuating nodes
intrinsic
- granulomatous infection
- sarcoid
- amyloid
- castleman
- treated lymphoma
- occupational lung diseases
- rosai dorgman
- papillary, bronchogenic, breast, mucinous, osteosarc
hypervascular
- kaposis
- papillary thyroid, NET, RCC
- castleman
- kimura
- kikuchi fujimoto
- angioblastic t cell lymphoma
mycosis fungoides is
a type of malignant cutaenous primary t cell lymphoma
Thyroglossal duct cyst imaging
Anywhere from foramen caecum to thyroid gland
typically infrahyoid and within 2cm of midline
US
usually simple
can be complex
assoc soft tissue lesion ?papillary ca vs ectpic thyroid
CT
usually simple
rim enhancement
can be embedded in the strap muscles
MR
T1 variable
T2 high
C+ rim can be
Lingual thyroid imaging and ddx
us
absent thyroid
ct
hyperdense soft tissue mass
homogenous enhancement
MR
well defined
T1 iso to hyper
T2 varibale
C+ strong
NM
tech or iodine scan
DDX
lingual tonsil
thyroglossal duct cyst
malignany
hamengioma
dermoid
Hyperthyroidism causes
Increased stim
- hcg secretion
- excess TSH secretion
- TSH receptor stim ab; graves
independant function
- functioning adenoma, multinodular goiture
Inflammation
- autoimmune (hashimotos, post partum)
- post viral (de quervins)
- infections
- iatrogenic
Extrathyroid
- dietary
- neoplasic (mets, pit adenoma, struma ovarii)
Iodine exposuire
Hypothyroidism causes
Primary
- autimmune
- iodine deficiency
- thyroiditis (post partum, subacute, riedel, silent)
- post radiation
- infiltrative (lymphoma, sarcoid, amyloid, tb)
Secondary
- pit adenoma
- pan hypopit
- post radiation
- infiltrative
Congenital
- absent thyroid
- ectopic/underdeveloped
- dyshormonogenesis
drug induced
Graves disease is
an autoimmune thyroid disease and most common cuase of thyrotoxicosis
caused by ab directed stimulation of the TSH receptor with increased prod and release to t3 and t4
Graves disease imaging
US
enlarged
hyperechoic
heterogenous
absence of nodularity
hypervascular (thyroid inferno)
NM
I123 homogeneously increased uptake
T99m homogeneously increased uptake
pyraimydal lobe
Thyroid dermopathy/acropachy
Graves ophthalmopathy
exophthalmos/palps/goitre = merseburger triad
Thyroid acropachy imaging
almost always assoc with ophthalmopathy
xr
symm hands and feet invovlement
tubular bones
prominent smooth flowing periosteal reaction
soft tissue swelling
Graves orbitopathy imaging
enlarged muscles
sparing of the musculotendinous junction
coke bottle
LPS - IR - MR - SR - LR - Obliques
exophthalmos
- 1cm to posterior sclera
- 2cm to anterior globe
- interzygomatic line
Graves orbitopathy ddx
pseudotumour
sarcoid
lymphoma
mets
amyloid
erdheim chester
Hashimotos thyroiditis is
a subtype of autoimmune thyroiditis
usually presents with hypo and a goitre
can present with hyper
anti tg antibodies, tpo
Hashimotos imaging
enlarged thyroid, can be atrophic later
heterogenous
hypoechoic micronodules with surrounding echogenic septations (pseudonodular/giraffe)
usually normal or decreased flow but can be hypervasc
prominent reactive cervical nodes
NM
early increased
late spots of reduced uptake
Thyroid lymphoma is/imaging
rare. usually non hodgkins. assoc with hashimotos.
imaging
similar to primary thyroid malignancies and hashimotos
US
nodular
diffuse
mixed
calcs are uncommon
CT
goitre
hypoattenuating
hterogenous enahncement
MR
t1/t2 iso to hyper
Goitre causes
non toxic simple
graves
mng
hashimotos
thyroid cancer
drugs/diet
depositional eg amyloid
misc; plummer vinson
Riedels thyroiditis is/imaging
a rare form of autoimmune thyroiditis, sometimes considerted a manifestation of igG4 disease
stony or woody
assoc
- retroperitoneal fibrosis
- sclerosing fibrosis
- orbital pseudotumour
- fibrosing mediastinitis
imaging
US
- homogenously hypoechoic with poor demarcation fo the gland borders
CT
compression of lcoal structures by an enlarged thyroid with low attenuation change areas within
MR
low on T1 and t2
De quervains thyroiditis is/imaging
a form of self limiting subacute thyroiditis usually preceded by an upper respiratory tract infection
hyper followed by hypo symptoms followed by euthyroid
US
poorly defined regions of decreased echos
decreased vasc in areas
NM
low uptake in a patient with hyperthyroidism
Follicular adenoma imaging
thin peripheral halo
predominantly cystic or mixed
isoechoic or anechoic
homogenous or hetero
absence of internal flow
Papillary thyroid cancer imaging
US
solitary mass irregular outline
small punctate microcalcifications
nodes can cavitate, have septa, mural nodules
CT
nodes have
- cystic components
- thick nodular walls
- septa
- sometimes calc
- sometimes purely cystic
MR
can have cystic bits
solid bits enhance
variable t2
NM
concentrates radioiodine but not pertechnetate
FDG avid
Follicular thyroid carcinoma imaging
typically hypoechoic
lacks cystic change
concentrates pertechnetate but not radioiodine
Medullary thyroid carcinoma imaging
sporadic or familial
- MEN 2a/b
- VHL
- NF1
US
- punctate foci of calc in primary and nodes
CT
irregular dense calcific foci
NM
do not concentrate radioiodine
FDG avid mets
concentrates thallium
Anaplastic thyroid carcinoma imaging
US
microcalc
usually infiltrative
CT
nodes
infiltrative primary
NM
no radioiodine uptake
Hyperparathyroidism assoc and subtypes
Assoc:
- MEN 1
- MEN 2a
- familial hypocalciuric hypercalcaemia
- familial isolated primary hyperparathyroidism
- hyperparathyroidism jaw tumour syndrome
Primary
- parathyroid adenoma
- parathyroid hyperplasia
- parathyroid cacinoma
- parathyromatosis
Secondary
- caused by chronic hypocalc with renal osteodystrophy (or malnurtriton, or vit d def)
- results in parathyroid hyperplasia
Tertiary
- autonomous parathyroid adenoma caused by chronic overstimualtion of hyperplasitc gflands in renal insufficicency
Hyperparathyroidism imaging
Subperiosteal bone resorption
- radial middle phalanges
- medial long bones
- lamina dura
Subchondral resorption
- clavs, PS, SIJ
Subligamentous resoprtion
- ischial tube
- trochanters
- inferior calcaneus and calvicle
Intracortical resorption
Terminal tuft erosion
Rugger jersey
Osteopaenia
Brown tumours
Salt and pepper skull
Chondrocalcinosis
Renal osteodystrophy/osteomalacia vit d
- osteopaenia
- subperiosteal resorption
- rugger jersey spine
- soft tissue calc
- superscan
- rib notching
Parathyroid adenoma imaging
Typically juxtathyroidal
Ectopic
- mediastinum
- retropharyngeal
- carotid sheath
- intrathyroidal
US
- homogenously hyopechoic
- echogenic capsule
- can show a feeding vessel on doppler
Tc99m sestamibi uptake
CT
intense arterial enchancement
washout on delayed
low attenuation on nc
polar vessel sign
variable MR findings
Parathyroid hyperplasia aetiology
Primary
- sporadic
- familial MEN 1 and 2a
Secondary
- renal failure
tv99m mibi
Parathyroid carcinoma imaging
invasiveness
calcifications
heterogeneity
lobulated morph
larger
negative predictors
- absence of suspicious vascularity
- absent thick capsule
- homogenity of capsule
Hypoparathyroidism causes
iatrogenic
congenital absence
familial
idiopathic
pseudo
- abnormal end organ resistance
pseudopseudo
- similar to pseudo without alterations in pth levels and calc metabolism
Hypoparathyroidism imaging
MSK
- focal and generalised osteosclerosis
- dense metaphyseal bands
- skull vault thickening
- subcut calc
- DISH
CNS
- intracranial calc
- cataracts
Pseudohypoparathyroidism imaging
MSK
- short stature
- brachydactyly
- soft tissue calc
- exostoses
- broad bones with coned epiphyses
CNS
- BG calc
- sclerochoroidal calc
- deep white matter calc
MEN 1
pituitary adenoma
islet cell tumours of the pancreas
parathyroid proliferative diseases
PiParPanc
MEN 2a
Phaeochromocytoma
Medullary thyroid cancer
Parathyroid hyperplasia
PMP
MEN 2b
phaeochromocytoma
medullary thyroid
marfanoid
mucosal neuroma/ganglioneuroma
PMMM
Orbital dermoid imaging
deep (within orbit) or superifical (adjacent to orbital rim)
most commonly upper outer quadrant
usually extraconal, non enhancing
smooth margins
cystic/solid components
heterogenous with internal fat
Orbital epidermoid is
a rare cause of an orbital mass
can be congenital or acquired
most commonly affect the eyelid but can be truly intraorbital
Retinal detachment types and aetiology
Rhegmatogenous
Non rhegmatogenous
- retinal break
- lattice degeneration
- tractional
- exudative
Rhegmatogenous
- posterior vitreous detachment
- trauma
Tractional
- Diabetic retinopathy
- sickle cell retinopathy
- retinopathy of prematurity
Exudative
- central serous chorioretinopathy
- vogt koyanagi harada disease
- coats disease
- choroidal neoplasms
Retinal detachment imaging
US
- bright continuous and folded membrane within the vitreous
- freely moving/aftermovement
- less mobile than posterior vitreous detachment
CT
- folded membranes within subretinal space
- limited anteriorly by the ora serrata
- posteriorly converges on the optic disc
Choroidal detachment aetiology
trauma
surgery
spontaneous
medications for lower iop
hypertension
neoplastic
inflammatory choroidal disordrs
caroticocavernous fistula
severe atherosclerosis
