eTable.

Indications for imaging studies of the head and neck

Indication	Primary	Alternative/Complementary
Temporal bone
Suspected complications of acute otitis media and otitis externa
extracranial, local	CT
intracranial	MRI
Chronic otitis media
unclear, suspected bony destruction	CT	(DVT?); MRI
Infectious processes: labyrinthitis
unclear clinical situation	MRI	CT
Sequelae of trauma	CT	MRI
Neoplasia
external auditory canal, middle ear	CT	MRI
inner ear, internal auditory canal, cerebellopontine angle	MRI	CT
jugular foramen	CT + MRI	DSA + embolization
Other
conductive hearing loss, anomaly of external ear	CT (DVT?)
hearing loss of combined or uncertain type	CT (DVT?)	MRI
sensorineural hearing loss/deafness	MRI	CT (DVT?)
planning for cochlear implant	MRI + CT (DVT?)
Postoperative
recurrent otitis media, prosthesis dislocation	CT (DVT?)	MRI
intracranial complication, tumor course, tumor recurrence	MRI	(CT)
complication after stapes surgery: early phase	no imaging	(CT, MRI)
complication after stapes surgery: late phase	CT (DVT?)	MRI
after cochlear implantation	CT (DVT?)
Isolated, non-traumatic peripheral facial palsy
acute onset with no improvement within 6 weeks	MRI
protracted onset: suspected lesion of parotid gland	US	MRI
protracted onset: suspected cisternal lesion, petrous part	MRI
protracted onset: suspected middle ear/mastoid lesion	CT	MRI
Tinnitus
subjective, non-pulsatile, no progression, no other symptoms	no imaging
tympanic membrane abnormal	CT	MRI
tympanic membrane normal, vascular risk factors	Doppler-US
tympanic membrane normal, no vascular risk factors	MRI
Masticatory apparatus
caries periodontal status	dental films, OPG
endodontal or periodontal infection/inflammation orthopedic problems of the jaw trauma	dental films, OPG	CT, DVT
cyst or other benign lesion before IV biphosphonate treatment	OPG	CT, DVT
osteonecrosis jaw lesion of unclear dignity	CT, (DVT?)	MRI
orthognathic surgical planning	X-ray	CT
implantation planning, complication planning of 3rd molar extraction	OPG	CT, DVT
TMJ: trauma	OPG	CT, DVT
TMJ: internal derangement, mass, inflammation/infection	MRI
Pharynx, oral cavity, larynx
neoplasia of nasopharynx, soft palate, oral cavity	MRI	CT, US, DSA + embolization
neoplasia of larynx, hypopharynx, other oropharynx	CT or MRI	US, DSA + embolization
infection/inflammation: acute, with suspected complication	US	CT, MRI
infection/inflammation: chronic, of uncertain clinical significance	cf. neoplasia
Dysphagia
suspected neoplasia or infection/inflammation	cf. neoplasia, inflammation
thyroid disease	US, medical work-up
functional globus sensation, foreign body, diverticulum	fluoroscopy (contrast swallow, with cinematography if ‧indicated)	C-spine films if a ventral ‧spondylophyte is suspected
suspected central origin	MRI	(CT)
Salivary glands
infection/inflammation, sialolithiasis	US	endoscopy, MRI, CT
neoplasia	US	MRI if staging unclear
Sjögren’s syndrome	US	MRI
Craniofacial region (e.g., paranasal sinuses)
acute infection/inflammation, odontogenic	dental films, OPG	CT, DVT
acute infection/inflammation, not odontogenic	no imaging	CT, MRI for complications
chronic infection/inflammation	CT (DVT?)	MRI
chronic infection/inflammation of uncertain clinical significance	MRI
trauma sequelae	special x-rays (zygoma, nasal bone), otherwise CT	MRI for intracranial complications
neoplasia	CT	MRI for (possibly) malignant tumors; DSA + embolization
vascular malformations	US	MRI, (DSA + embolization)
Disorders of the nose and of the sense of smell
infection/inflammation	CT	MRI
neoplasia, benign	CT	MRI, DSA + embolization
neoplasia, unclear or malignant	MRI	CT, DSA + embolization
after trauma	CT	MRI
Epistaxis
uncontrollable bleeding	DSA with embolization
clinically stable; hypertension and/or coagulopathy	medical work-up
clinically stable; other causes	CT	MRI, DSA+embolization
Neck
trauma	CT	MRI, DSA + embolization
vascular pathology	US	MRI- or CT-angiography
neoplasia	MRI	CT; US for further investigation of lymph nodes
Orbits
myositis, endocrine orbitopathy	US	MRI
abscess, phlegmon	CT or MRI
retrobulbar neuritis	MRI
trauma	CT	MRI
neoplasia	US; retrobulbar, MRI	MRI, CT
protrusio bulbi	US	CT for trauma, otherwise MRI

CT, computed tomography; MRI, magnetic resonance imaging; DVT, digital volume tomography; DSA, digital subtraction angiography; OPG, orthopantomography; TMJ, temporomandibular joint; US, ultrasonography