Most common 4 Flashcards
LS
1
Q
MC malignant tumor found in the parotid space / MC malignant lesion of the parotid gland / MC malignant parotid tumor in children
A
mucoepidermoid carcinoma
2
Q
MC site of origin of salivary duct ca
A
parotid gland
3
Q
MC site of acinic cell carcinoma
A
parotid gland (2nd MC: minor salivary glands)
4
Q
MC malignant tumor seen in the submandibular gland / MC malignancy in the submandibular gland
A
adenoid cystic ca (submandibular gland malignancy is rare)
5
Q
MC location of adenoid cystic carcinomas
A
parotid gland, submandibular gland, and palate
6
Q
MC type of malignant minor salivary gland tumor / MC malignant salivary gland tumor to arise in children and adolescents under 20
A
mucoepidermoid ca
7
Q
3rd MC sinonasal maligancy of the minor salivary glands after ACC and adenoca
A
mucoepidermoid ca
8
Q
MC site of mucoepidermoid ca in minor salivary glands
A
palate
9
Q
MC location of minor salivary gland tumors
A
palate and upper lip region
10
Q
MC implicated etiologic factor for mucoepidermoid ca
A
radiation
11
Q
2 epithelial tumors accounting for 50% of all lacrimal gland tumors
A
BMT and adenoid cystic ca
12
Q
MC malignant tumor in the lacrimal gland
A
adenocystic ca
13
Q
2nd MC malignant tumor of the trachea after squamous ca
A
adenoid cystic ca
14
Q
2nd MC malignancy of the parotid gland
A
adenocystic ca
15
Q
2 most commonly encountered tumors of the carotid space
A
paraganglioma and schwannoma
16
Q
3 MC lesions of the CS
A
paraganglioma (glomus jugulare, vagale or carotid body tumor), schwannoma usually vagal, squamous cell carcinoma nodal mets
17
Q
Retropharyngeal space lesions involving the entire space are most commonly?
A
abscesses (that have broken out of retropharyngeal space supporative nodes) and extranodal squamous cell carcinoma
18
Q
By far the 2 MC lesions seen in the perivertebral space
A
abscesses from vertebral body osteomyelitis and metastatic tumor that spreads from the adjacent vertebral body
19
Q
Most commonly seen lesions in the lateral retropharyngeal nodal chain
A
inflammatory nodal disease and nodal tumors (SCC, NHL, and other mets)
20
Q
MC example of malignant tumor breaking out of their space of origin and invading the PPS
A
SCCa of the pharyngeal mucosal space of the nasopharynx and oropharynx (invading laterally into the adjacent PPS)
21
Q
MC error made when interpreting images of the PMS area
A
labeling normal asymmetry as tumor
22
Q
Most commonly involved component in the pharyngeal ring hypertrophy/hyperplasia
A
adenoid component
23
Q
MC secondary infection of the PPS
A
pharyngitis progressing to PMS abscess
24
Q
MC location of posintflammatory calcification / calcification in the PMS
A
faucial tonsil
25
Largest muscle of mastication
masseter
26
MCC of the acquired form of benign masseteric hypertrophy
bruxism (nocturnal molar grinding)
27
Best plane to ensure the visualization of the parotid duct
parallel to the hard plate
28
MC connective tissue disease in Sjogren's syndrome
rheumatoid arthritis
29
Single most important nerve within the CS
vagus nerve
30
Most commonly involved peripheral nerves by schwannoma
cervical spinal roots, vagus nerve, and sympathetic plexus
31
MC primary site of SCCa that spreads into the nodes of the RPS
nasopharyngeal mucosal space
32
MCC of retropharyngeal nodal tumor
SCCa nodal metastasis
33
In the urban enviroment MCC of vertebral body infection, especially in young patients
tuberculosis
34
MCC of bacterial osteomyelitis
Staph aureus (2nd MCC: Enterobacter sp)
35
MC locations of minor salivary glands in the OC
inner surface of the lip, buccal mucosa, and palate
36
MC lesion requiring imaging in the mucosal area of the OC / MC malignancy of the mucosal area of the OC / MC malignancy in the SLS
SCCa
37
MC task in the mucosal area of the OC required of the radio
staging of SCCa
38
MC origin of all branchial cleft anomalies / Of all branchial cleft anomalies, 95% arise from the?
remnant of the 2nd branchial apparatus
39
MC form of second branchial cleft cyst
cystic mass w/o sinus or fistula at the angle of the mandible
40
MC location of (2nd) branchial cleft anomalies in a child
angle of the mandible
41
MC location of the cystic component of 2nd branchial cleft anomaly
mandibular angle, just lateral to glossopharyngeal and hypoglossal nerves
42
MC location of second branchial cleft cyst
mandibular angle just lateral to the CNIX and CNXII in the posterior submandibular space (b/n SMS and the CS)
43
MC benign mandibular tumor
ameloblastoma (1% of all jaw tumors)
44
MC cystic lesion of the mandible
radicular cyst
45
MC thyroid cancer type
papillary (2nd MC: follicular)
46
Thyroid ca w/ the best prognosis
papillary
47
Thyroid ca w/ the worst prognosis
giant cell/anaplastic
48
Preferred cross-sectional imaging tool when evaluation of thyroid malig is required as presurgical guide
MRI (CT not recommended because the iodine can take months to clear - can postpone I-131 therapy for up to 6 months)
49
MC neck tumor to follow the paraesophageal or paratracheal nodal chain
thyroid ca
50
MC etiology of acute thyroiditis
viral
51
MCC of abscess of the CS
extracapsular spread of infection from suppurative LNs
52
Larger lipomas in the head and neck region are almost always found within the?
PCS
53
MC multispatial diseases
inflammatory processes as well as malignancy involving the LNs
54
MC congenital cystic neck masses
branchial cleft cysts (first, second, third), thyroglossal duct cyst, cystic hygroma-lymphangioma, dermoid/epidermoid
55
MC location of thyroglossal duct cyst
midline at or just below the hyoid bone
56
MC location of TDC
near the hyoid bone
57
Preferred method for laryngeal radiologic examination in the clinical setting of nonmalignant disease of the larynx (laryngocele, TDC, posintubation, trauma)
CT
58
Largest laryngeal cartilage
thyroid cartilage
59
Overwhelming preponderance of malignant tumors of the larynx (98%)
SCCa (sarcoma, esp chondrosarcoma, is the rare exception)
60
Ca from one cord most commonly accesses the contralateral vocal cord across the?
anterior commissure
61
Rarest form of laryngeal ca (5%)
subglottic ca
62
Chondrosarcoma primarily arises in the?
cricoid cartilage (90%)
63
MC form of cartilaginous injury during intubation
dislocation of an arytenoid cartilage (displaced anteriorly)
64
MC site of fracture of the thyroid cartilage in blunt trauma to the anterior neck
anterior margin
65
MC presentation of chronic laryngeal injury
suspected anterior neck mass where CT shows an infolded thyroid ala and tilted larynx
66
MC fracture of the cricoid ring
posterior midline fracture associated w/ 1 or 2 anterolateral ring fractures
67
Most lateral aspect of the posterior hypopharyngeal wall
posterior wall of the pyriform sinus
68
MC site of carcinomas of the hypopharynx
pyriform sinus > postcricoid airea > posterior pharyngeal wall
69
MC route of spread for pyriform sinus ca
posterolaterally into the soft tissues of the neck
70
Carries the worst prognosis of the 3 subsites of the hypopharygeal ca
postcricoid carcinoma
71
MCC of nodal mass with normal mucosal surface
submucosal "unknown" primary in the nasopharynx
72
Most commonly involved CNs in perineural spread
trigeminal (V3 and V2) and facial nerves
73
Location of primary tumor that requires the most extensive scan extent
nasopharynx
74
Largest communication b/n orbit and intracranial area
superior orbital fissure
75
MCC of macrophthalmia
juvenile glaucoma or myopia
76
Most severe form of macrophthalmia
buphthalmos (caused by juvenile-onset glaucoma)
77
MC tumor of the globe during childhood / Som: MC intraocular tumor of childhood
retinoblastoma
78
MC primary intraocular malignancy in adults
uveal melanoma
79
MC site of uveal melanoma
choroid
80
MC site of metastatic tumor to the globe
uveal tract (vascular layer between the retina and sclera)
81
MC primary lesions to metastasize to the globe
lung and breast ca
82
MC type of thickening of the optic nerve/sheath complex
tubular thickening
83
Accounts for 80% of primary tumors of the optic nerve / Som: mc optic nerve tumor in children / Som: MC orbital neoplasm seen in association w/ NF
optic nerve glioma
84
Histologically, childhood optic nerve glioma is most commonly a?
low-grade malignancy of the pilocytic astrocytoma (adults - glioblastoma)
85
MC thickening/configuration/shape of optic nerve glioma
tubular
86
2nd MC primary neoplasm of the optic nerve/sheath complex
optic nerve sheath meningioma
87
MC thickening/configuration/shape of optic nerve sheath meningioma
tubular
88
MCC of intraorbital mass lesion in adults
pseudotumor
89
Most commonly involved orbital structure in orbital pseudotumor
retrobulbar fat > EOM > optic nerve > uveal-sclera > lacrimal
90
MCC of unilateral or bilateral exophthalmos in adults / Som: MCC of unilateral and bilateral exophthalmos in the adult population
thyroid ophthalmopathy / thyroid orbitopathy / Graves' dysthyroid ophthalmopathy
91
Most commonly involved EOM in thyroid ophthalmopathy
inferior rectus > medial > lateral > superior rectus (IM L. SO?)
92
Most ommonly involved EOM in thyroid orbitopathy
inferior rectus > medial rectus > superior rectus (consistent sa IMSLOw ng radiopedia)
93
MC orbital tumor
cavernous hemangioma
94
MC orbital vascular tumor in adults
cavernous hemangioma
95
MC vascular masses (in children)
capillary hemangioma and lymphangioma
96
3rd MCC of proptosis
orbital lymphoma (after orbital pseudotumor and cavernous hemangioma) (wait! ano difference ng proptosis at exophthalmos haha)
97
MC location of orbital lymphoma
lacrimal gland (extraconal) > conal-intraconal > optic nerve sheath/complex
98
MCC of acute, inflammatory enlargement of the lacrimal gland in younger patients
postviral syndrome
99
MC meningioma in the extraconal area
sphenoid wing meningioma
100
MC orbital location of Paget disease
roof and lateral wall
101
Most important anatomic area on the lateral wall of the nose
middle meatus
102
Largest of the parasympathetic ganglia assoc w/ the trigeminal nerve
pterygopalatine ganglion
103
MCC for recurring inflammatory sinonasal disease
dysfunction of mucociliary drainage
104
Primary offending organisms in fungal sinusitis
Mucor and Aspergillus
105
MC mucosal complication of chronic sinusitis
inflammatory polyp
106
Most frequently involved in inflammatory polyps
nose and maxillary sinus
107
Most commonly affected by mucous retention cysts
maxillary sinus
108
MC CT finding indicating the need for endoscopic surgery
opacified ostiomeatal unit (esp the infundibulum) w/ ostiometal unit pattern
109
Sinus most commonly affected in Wegener's granulomatosis
maxillary sinus
110
MC PNS cancer
SCCa of the maxillary sinus > ethmoid (sphenoid and frontal so rare)
111
MC malignant tumor of the PNS and nose
SCCa
112
MC LN group to be involved in maxillary sinus SCCa
retropharyngeal chain
113
MC location of de novo osteosarcoma within the head and neck region
maxillary sinus > mandible > calvarium (not seen as primary to the nose)
114
MC site of maxillary de novo osteosarcomas
alveolar ridge
115
MC head-neck site of occurrence of chondrosarcoma (although rare)
sinonasal
116
Largest part of the membranous labyrinth
vestibule
117
MC error when imaging peripheral facial nerve paralysis w/ either CT or MRI
to complete an unfocused scan of the brain w/o attempting to localize the lesion topographically
118
Portion of the facial nerve usually out of place if ectopic
posterior tympanic and mastoid
119
MC form of acquired cholesteatoma
pars flaccida cholesteatoma / attic or primary acquired cholesteatoma
120
MC site for pars flaccida cholesteatoma
Prussak's space
121
MC sites of hemangioma/ossifying hemangioma
labyrinthine segment of the facial nerve and the geniculate fossa area
122
MC missed cause of congenital deafness
vestibular aqueduct syndrome
123
MC type of otosclerosis/otospongiosis
fenestral
124
MC CT finding in fenestral otosclerosis
new bone formation (plaque) on the anterior oval window margin/fissula antefenestram
125
Weakest ossicle joint and therefore most susceptibe to injury / Most commonly dislocated
incudostapedial joint
126
MC variety of posttraumatic ossicular disruption
incudostapedial subluxation
127
MC site of ossicular discontinuity
incudostapedial joint and lenticular process of the incus
128
Most vulnerable ossicle / Most ossicular discontinuities involve this ossicle
incus (relatively heavy but provided only w/ minor ligamentous support by the posterior incudal ligament)
129
Most frequently malformed or absent ossicle
either incus or stapes
130
Accounts for 70-80% of temporal bone fractures
longitudinal
131
MC type of temporal bone fracture
longitudinal > transverse, oblique, mixed-type
132
Most complex and clinically impt part of the skull base
between the anterior aspect of the sella and the posterior lip of the foramen magnum / basisphenoid and basiocciput
133
Most commonly misdiagnosed pseudomass in the skull base
many varied signals that may be seen associated w/ the jugular bulb on MRI / complex flow in the jugular bulb
134
Fluid in the petrous apex air cells most commonly follow what signal?
CSF/water signal
135
MC sites for CSF leakage
tegmen tympani (CSF otorrhea) and cribriform plate/fovea ethmoidalis (CSF rhinorrhea)
136
MC presentation of tumors in the jugular foramen
complex cranial neuropathy including CN 9, 10, 11
137
MC site of neural sheath tumors in the CN's exiting the skull base
jugular foramen (9, 10, 11)
138
MCC of malignant tumor of the skull base
metastasis
139
MC primary sites of skull base mets
lung, breast, and prostate gland
140
MC location of skull base chondrosarcoma
area of the paramedial basisphenoid synchondrosis
141
Most commonly thought etiology of Paget disease
viral
142
MC causes of acquired cephalocele
surgery or trauma
143
MC location of atretic cephalocele (contains just dura, fibrous tissue, and degenerated brain tissue)
obelion (sagittal suture at the level of the parietal foramina)
144
MC type of cephalocele in European/North America Caucasians / MC type of cephalocele among Caucasians
occipital
145
MC location of congenital cephalocele
squamous portion of occipital bone
146
MC type of cephalocele in SEA
frontoethmoidal
147
MC type of cephalocele among Australian aborigines, Malaysians, and select Southeast Asian groups
sincipital (sabi ni Osborn synonymous ang frontoethmoidal at sincipital)
148
Most cephalad of the nerves in the cavernous sinus
III
149
MCC of simple trochlear nerve palsy
trauma
150
MC ocular motor nerve palsy
isolated abducens palsy
151
Only major branch of the trigeminal nerve that carries both sensory and motor fibers
V3
152
Largest portion of the facial nerve
branchial motor portion
153
Least well-vascularized portion of the intratemporal facial nerve
labyrinthine segment
154
MC causative agents of Bell's palsy
herpes simplex I and VZV
155
MCC of hemifacial spasm
compression of the facial nerve root exit xone on the caudal brainstem by loops of otherwise normal appearing vessels
156
MC finding on MRI w/ MRA in patients with hemifacial spasm
tortuous vertebral artery swinging up into the CPA, with the PICA making contact w/ the root exit zone of the facial nerve
157
MCC of isolated injury to nerve XI
radical neck dissection
158
Most responsible for unilateral sensorineural hearling loss
lesions of the CPA
159
MC location of arachnoid cysts
sylvian, parasagittal, and convexity (less frequently in CPA, incisura, suprasellar, and 4th ventricle)
160
2nd MC CPA mass
meningioma
161
MC signal characteristic of epidermoid
T1 hypo, T2 hyper - keratin debris predominates
162
The one inflammatory lesion found with any frequency during the search for causes of sensorineural heraing loss
multiple sclerosis
163
MC site of pars flaccida cholesteatoma
Prussak's space
164
MC site of (primary/congenital) cholesteatoma
epitympanum
165
Provide most of the facial mesenchyme
neural crest cells
166
MC facial birth defect
cleft lip and palate (2nd MC: hemifacial microsomia [Goldenhar syndrome, OAV complex])
167
MC facial cleft type
common cleft lip/cleft palate
168
MC type of tori palatini
flat and spindle-shaped (86% combined)
169
Most visible feature of the bilateral cleft nose
shortening and deficiency of the columella centrally, with splaying and caudal displacement of the alar cartilages to both sides
170
MC finding / One obligatory finding in median cleft face syndrome
hypertelorism (2nd MC: true midline bony clefting of the nose)
171
Extranasal gliomas are most frequently on what side?
right
172
MC type of cephalocele among Caucasians
occipital
173
MC type of cephalocele among Australian aborigines, Malaysians, and select Southeast Asian groups
sincipital
174
MCC of neonatal nasal obstruction
choanal atresia (2nd MCC: dacryocystoceles)
175
MC congenital brain malformation in humans
holoprosencephaly
176
Most severe form of holoprosencephaly
alobar
177
Most frequently seen form of holoprosencephaly in clinical practice
semilobar
178
Most affected structures in the upper face in hemifacial microsomia
zygoma and lateral maxilla
179
Most severely affected structure in the lower face in hemifacial microsomia
mandible
180
Accounts for most of the asymmetry seen in hemifacial microsomia
mandibular hypoplasia
181
MC epibulbar tumor in children
choristoma
182
MC location of choristomas
subconjunctival
183
Most important functions of the uvea
to provide a vascular supply to the eye and to regulate the ocular temperature
184
Cones are most dense at the?
fovea
185
MCC of cranial asymmetry
positional deformation of the posterior aspect of the head / posterior positional plagiocephaly
186
MC referral for possible synostosis
benign, remediable positional deformation of the skull (not a true premature suture synostosis)
187
MC forms of nonsyndromic synostoses or primary craniosynostoses
premature sagittal, coronal, and metopic synostoses
188
Least common form of nonsyndromic synostoses or primary craniosynostoses
lambdoid (affects midface only incidentally)
189
MC craniofacial dysostosis
Crouzon syndrome (acrocephalosyndactyly type II)
190
Most important surgical component of the septum due to its supportive function
quadrangular cartilage
191
Most inferior part of the septum
columella
192
MCC of anosmia
frontal trauma (but total anosmia is 5x more likely after occipital trauma causing a contra-coup shearing of the olfactory fibers)
193
The most important of the 5 arteries that supply the nasal cavity
sphenopalatine artery
194
Most accessible part of the ethmoid intranasally, when present
aggar nasi cells
195
Represents the most anterior ethmoid air cell, usually lying deep to the lacrimal bone; anterior, lateral, and inferior to the frontal recess; remnant ethmoturbinal and present in nearly all patients
aggar nasi cell
196
Lack of any sinus pneumatization of the sphenoid bone by age of 10 years is most commonly seen in?
diseases that require a large marrow demand to compensate for chronic anemia (thalassemia and chronic renal failure)
197
Most accurate assessment of mucosal soft-tissue disease and bone is accompished at ____ window settings.
wide
198
Best distinction of watery sinonasal secretions from more viscous or desiccated secretions or a tumor requires _____ window settings.
narrow
199
Most posterior medial wall of the maxillary antrum is formed by the?
vertical portion of the palatine fossa
200
Layer of the scalp in w/c runs most of the blood vessels and cutaneous nerves
superficial fascia or tela subcutanea
201
Supplies most of the forehead and scalp
superficial temporal artery
202
Narrowest anterior air channels
frontal recesses
203
MC site of concha bullosa
middle turbinate
204
Largest and most constant anterior ethmoid air cells
ethmoid bulla
205
MC site of excessive medial deviation and bony dehiscence of the lamina papyracea / Most delicate portion of the lamina papyracea
site of insertion of basal lamella into the lamina papyracea
206
MC type of optic nerve
Type 1 - course immediately adjacent to the sphenoid sinus, w/o indentation of the wall or contact w/ the posterior ethmoid air cell
207
MC location of acute sinusitis
ethmoid sinus
208
Sinuses most commonly involved w/ chronic sinusisits
anterior ethmoid air cells
209
MCC of orbital infection
complicated sinusitis (MC origin of infection: ethmoid > frontal > sphenoid > maxillary)
210
Most commonly performed FESS techniques
types II and III
211
Area most likely to be affected by inflammatory disease in a patient w/ a prev PNS surgical procedure
frontal recess
212
Single most important risk factor for iatrogenic CSF leak
previous FESS
213
Thinnest portion and the area most exposed to perforation
lateral cribriform plate / lateral lamella of the olfactory groove (because anterior ethmoid artery enters the olfactory fossa at this location)
214
Most vulnerable location of the anterior ethmoidal artery
superior aspect of the lamina papyracea, near the level of the superior oblique and medial rectus muscles, where the AEA runs within the anterior ethmoidal canal and perforates the bony ethmoid wall
215
MC endoscopic finding following FESS and one of the MC reasons patients return for revision surgery
recurrent or residual polyps
216
MC CT finding in a patient w/ failed FESS
mucosal disease (w/ or w/o assoc anatomic fractures) - anterior ethmoid > maxillary > posterior ethmoid > frontal > sphenoid
217
MC infectious malady of the URT
common cold
218
MC causative agents of common cold
rhinoviruses, parainfluenza and influenza viruses, adenoviruses, and RSV
219
Most likely to spread intracranially
acute frontal sinusitis (due to rich venous emissary plexus between the posterior frontal sinus mucosa and the meninges) (next MC: sphenoid and ethmoid sinusitis)
220
Most likely to spread to the orbits / Most often implicated as the source of infection for orbital complications
ethmoid > sphenoid and maxillary > frontal
221
Air-fluid levels are MC in what sinuses?
maxillary
222
MCC of PNS air-fluid level
bacterial sinusitis
223
MCC of ethmoid air-fluid (although uncommon)
rupture of ethmoid mucocele (invariably mucopyocele)
224
MCC of mycotic sinonasal disease / Assumed cause of most allergic fungal sinusitis cases
Aspergillus
225
MC and most lethal of the opportunistic fungal infections among immunocompromised patients
candidiasis (MC: Candida albicans) (maxillary sinuses - almost exclusively involved)
226
MC complications of inflammatory rhinosinusitis
polyps and cysts (MC: retention cyst)
227
MC location of mucous retention cysts
maxillary sinus
228
MC expansile lesions in the nasal cavity
polyps
229
MC expansile lesion to develop in a PNS
mucocele
230
MC location of mucoceles
frontal sinuses (2nd MC: ethmoid > maxillary and sphenoid)
231
Osteomyelitis of the bones of the face and PNS is most often found following?
osteoplastic flap procedure for frontal sinus inflammatory disease
232
Radiation osteitis is probably most commonly encountered in the?
mandible
233
MCC of high-attenuation material within the sinus
desiccated secretions (differential: mycetoma in fungal sinusitis and intrasinus hemorrhage)
234
Highest incidence of surgical complication of all mucoceles
sphenoid sinus mucoceles
235
Due to the proximity of sphenoid sinus mucoceles to the optic nerve, what is the most serious major postop complication?
blindness
236
MC sinuses involved in mycotic sinusitis
either maxillary or ethmoid
237
MC form of Actinomyces infection
cervicofacial
238
Most commonly affected sinuses in sarcoidosis
maxillary and ethmoid
239
MC sites of inflammatory pseudotumor / MC sites of inflammatoty myofibroblastic tumor
lung, liver, and GIT (omentum and mesentery)
240
MC tumors with multiple sinonasal calcifications
olfactory neuroblastomas, inverted papilloma, or chondroid tumor
241
A unilateral polypoid nasal mass with calcifications is most likely to be?
either olfactory neuroblastoma or inverted papilloma
242
2 MCC of anosmia
idiopathic and sinonasal inflammatory disease
243
MC neoplasm affecting the PNS and nasal cavities (rare)
carcinomas
244
A nasal septal mass with calcifications is most likely to be?
either a chondroid tumor or result of fungal disease
245
MC location of carcinomas of the nasal cavity
nasal septum near the mucocutaneous junction
246
MC tumors that metastasize to the head and neck
kidney, lung, breast, testis, and GIT
247
MC site of salivary gland tumors
palate (and then extend into nasal fossae and PNS)
248
MC location of BMTs of the sinonasal cavities
nasal fossa (2nd MC: maxillary sinus)
249
Most specialized and differentiated neuroendocrine tumors
olfactory neuroblastoma
250
MC site of malignant melanomas in the sinonasal cavities
nasal septum
251
MC sites of schwannomas
vagus nerve in the neck and the CN 8
252
2nd MC group of extranodal lymphomas after GI lymphomas in Asians
sinonasal lymphoma
253
MC location of sinonasal lymphomas
nasal fossae and maxillary sinuses
254
MC member of a group of diseases known collectively as plasma cell dyscrasias
multiple myeloma
255
MC location of hemangiomas of the nasal cavity
septum (anterior septum near Kisselbach's plexus) > lateral wall > vestibule
256
MC type of hemangiomas of the nasal cavity
capillary
257
MC sites of hemangiomas in the head and neck
skull > mandible > nasal bones > cervical vertebrae
258
MC sites for hemangiopericytomas
lower extremities and retroperitoneum-pelvis (3rd MC: head and neck - neck, perioral STs, and sinonasal tract)
259
MC sites of head and neck leiomyomas
cervical esophagus > subcutis > oral cavity
260
Site of preference of leiomyomas in the nasal cavity and sinuses
turbinate
261
Cardiac rhabdomyomas are most commonly assoc w/?
tuberculosis
262
MC ST sarcoma in children / MC ST malignancy of childhood / MC primary malignant orbital tumor in children
rhabdomyosarcoma
263
MC sites for all rhabdomyosarcomas in the head and neck
orbit > nasopharynx > middle ear and mastoid .... > oral cavity
264
MC sites for liposarcomas above the clavicles
soft tissues of the neck, scalp, and face
265
MC benign PNS tumor associated w/ spontaneous CSF rhinorrhea, pneumocephalus, and tension pneumocephalus
osteoma
266
MC site of osteomas
frontal sinuses (2nd MC: ethmoid sinuses)
267
MC site of osteomas
PNS, especially the frontal and ethmoid sinuses (next MC site: jaw = mandible > maxilla)
268
MC site of head and neck "osseous" osteochondromas
mandible (coronoid process and condyle)
269
Most commonly affected bones in osteoid osteoma
femur and tibia
270
MC sites of osteoblastoma
vertebral column and long bones of the appendicular skeleton
271
MC location of ossifying fibromas
tooth-bearing regions - molar or premolar regions of the mandible > maxilla
272
MC site of monostotic fibrous dysplasia (75-80% of cases are monostotic)
ribs and femur
273
MC site of malignant transformation w/ FD
craniofacial bones (irradiation may promote it)
274
MC location of Paget's disease in the head and neck
calvaria, maxilla, and mandible
275
MC primary bone sarcoma after the 1st decade of life
osteogenic sarcoma
276
MC primary bone sarcoma after the 4th decade of life
chondrosarcoma
277
MC location of primary osteogenic sarcoma (absence of previous irradiation or Paget's disease)
distal femur, prior to closure of the growth plates
278
MC location of primary chondrosarcoma
pelvic region and femur
279
MC location of follicular/dentigerous cysts
mandibular 3rd molars, maxillary canines and 3rd molars
280
MC jaw cyst
periodontal cyst
281
MC odontogenic cyst
periapical (radicular) cyst (2nd MC: dentigerous)
282
MC site of periodontal cysts
maxillary teeth
283
MC location of lateral periodontal/paradental cyst
premolar and cuspid areas
284
MC type of odontogenic keratocyst
central parakeratotic
285
Most commonly encountered nonodontogenic jaw cysts
developmental cysts
286
nasopalatine duct cyst (incisive canal cyst)
nasopalatine duct cyst (incisive canal cyst)
287
MC odontogenic tumors
ameloblastoma, cementoma, odontoma, and fibromyxoma
288
MC site of ameloblastoma
mandible
289
MC site of metatasis from ameloblastoma
lungs, pleura, and regional LNs
290
MC complication in cementoblastoma
osteomyelitis
291
MC primary tumor below the clavicles to metastasize to the sinonasal cavities
RCC
292
Contains both the most and least water-laden soft tissues in the body
globe (most - vitreous; least - lens)
293
Most extreme form of macrophthalmia (inc IOP, enlarged globe, enlarged cornea)
buphthalmos
294
MCC of macrophthalmia
axial elongation of the eye assoc w/ high myopia
295
MC choroidal neoplasms producing retinal detachment in adults
malignant melanomas and choroidal hemangiomas
296
Prob the MCC of dytrophic intraocular calcification
chronic posttraumatic degeneration
297
MCC of phthisis bulbi
trauma or infection
298
MCC of focal calcification, near the surface of the optic nerve
drusen
299
MC presenting sign of retinoblastoma / MC sign assoc w/ retinoblastoma
leukokoria (2nd MC sign: strabismus)
300
MCC of proptosis in children
orbital cellulitis
301
MC orbital masses (in children)
dermoid and epidermoid cysts
302
MC metastatic cancer of the orbit in children
metastatic neuroblastoma
303
MC source of secondary carcinoma within the eye
breast or lung
304
Most useful in evaluating the challenging retinoblastoma patient
MRI
305
MC causes of leukokoria
retinoblastoma, PHPV, ROP, Coat's, posterior cataract, coloboma of the choroid or optic disc, uveitis, larval granulomatosis)
306
MCC of leukokoria in childhood, except for retinoblastoma
PHPV
307
Most highly vascular portion of the eyeball
uvea - provides a suitable substrate for tumor cells
308
MC neoplasm involving the choroid
malignant melanoma
309
MC site of uveal nevi
posterior 1/3 of the choroid
310
Usually the most immediate concern for imaging in ocular trauma
possible presence of foreign body (localization is most often accomplished by CT)
311
Probably the MC postsurgical change seen at imaging
artificial intraocular lens placed after cataract extraction
312
Most important structure traversing the IOF
maxillary nerve
313
Most important contents of the PPF
maxillary nerve, pterygopalatine (sphenopalatine) ganglion, and terminal part of the maxillary artery
314
The intracanalicular portion of optic nerve is supplied almost exclusively by:
ophthalmic artery
315
MC causes of pseudoproptosis
minor degrees of facial and orbital asymmetry
316
In practice, most of the time, plagiocephaly is seen in patients with?
hemicoronal premature synostosis
317
MC developmental cysts involving the orbit and periorbital structures
dermoid and epidermoid cysts, choristomas, and teratomas
318
MC locations of demoid and epidermoid cysts in the orbit
superior and temporal / superior temporal quadrant of the orbit, where they are fixed to the periosteum near the frontozygomatic suture line
319
MC locations of demoid and epidermoid cysts in adults
behind the orbital rim, often near the lacrimal gland
320
MCC of orbital cellulitis
sinusitis
321
MC fungal organisms incriminated in orbital cellulitis
Mucor and Aspergillus
322
MC form/type of mucormycosis
rhinocerebral
323
MC ophthalmologic disease among orbital disorders after Graves' disease
pseudotumor
324
Most commonly affected muscles in idiopathic orbital myositis
superior complex and medial rectus
325
MC sign of sarcoidosis
anterior uveitis
326
MC form of orbital involvement in sarcoidosis
chronic dacryoadenitis
327
MC extrathoracic manifestations of sarcoidosis
visual system abnormalities
328
MC connective tissue disorders that may be associated w/ systemic vasculitis
SLE, RA, and dermatomyositis
329
MC granulomatous and histiocytic lesion in the orbit / MC mesenchymal tumor of the orbit / MC adult mesenchymal tumor of the orbit
fibrous histiocytoma
330
Most commonly involved by LCH
frontal bone (lesions are usually in the superior or superolateral wall of the orbit in a rather anterior location)
331
MC location of capillary hemangiomas
superior nasal quadrant
332
MCC of spontaneous orbital hemorrhage
orbital varices
333
Plexiform neurofibromas in infancy or childhood most commonly involve the?
eyelids
334
MC location of schwannomas in the orbit
intraconal space
335
MC tumors involving the optic nerves
optic nerve sheath meningiomas and gliomas
336
MCC of optic neuritis
multiple sclerosis (visual loss is typically unilateral)
337
MC source of mets to the orbit
breast ca in women; ca of the lung, kidney, or prostate in men
338
Intracranially, most of the foramina converge to the region of the?
cavernous sinus and Meckel's cave
339
Most meningoceles are found in the?
midline
340
MC lesions in the greater wing of sphenoid
meningiomas or bone-related tumors (no fissures or foramina, it's simple bone covered by dura)
341
MC site of chondrosarcomas in the skull base
petro-occipital (petroclival) synchondrosis or fissure - off midline; junction of the nasal septum and the rostrum of the sphenoid
342
MC location of meningiomas
convexities or parasagital / parasagittal/convexity
343
Primary blood supply of juvenile angiofibroma is almost always from the?
the terminal branches of the internal maxillary or the ascending pharyngeal arteries
344
CN most commonly affected in the central skull base by scwhannomas
trigeminal
345
MC site of CSF breech
anteriorly through the region of the cribriform plate or ethmoid roof (2nd MC: temporal bone, where fractures may be assoc)
346
Cranial nerves most often involved in PNS from head and neck cancer
trigeminal and facial nerves
347
MC location of ectopic calcifications in basal cell nevus syndrome
falx cerebri and other areas of the dura
348
MC presenting symptom of ameloblastoma
swelling
349
MC site of unilocular ameloblastoma
maxilla
350
Mildest and most favorable form of histiocytosis X
eosinophilic granuloma
351
MC location of hemangiomas
skull and vertebrae
352
MC primary tumors of mets to the mandible and maxilla
breast, lung, kidney (hypernephroma), thyroid, prostate, and stomach
353
MC missing teeth excluding the 3rd molars
mandibular 2nd premolars > maxillary lateral incisors
354
MC site of dens in dente (dens invaginatus)
permanent upper lateral incisors
355
Densest material in the human body
normal enamel
356
MC location of dehiscences in the facial canal
tympanic portion near the oval window region
357
Mediates most of the sensations that have to do w/ linear acceleration of the head
macula of the utricle
358
Segments of the facial nerve canal that are most commonly affected in congenital aural dysplasias (CAD)
tympanic and mastoid segments
359
MC temporal bone dysplasia in cases of profound congenital sensorineural hearing loss
Scheibe's dysplasia
360
Aside from Scheibe's deafness, MC form of genetic deafness
Mondini's malformation
361
MC location of bifurcation in duplication of the facial nerve / bifid facial nerve
along the proximal aspect of the tympanic segment inferior to the lateral semicircular canal
362
MC vascular anomaly of the petrous portion of the temporal bone
high jugular bulb
363
MC microfissures (in the temporal bone) near the round window
Hyrtl's fissure and fissula antefenestram
364
2nd MC disease of childhood after URTI
otitis media
365
MCC of debris in the middle ear
granulation tissue
366
MC site of origin of acquired cholesteatomas
superior pars flaccida portion of the TM
367
Most widely accepted theory concerning the etiology of acquired cholesteatoma
arises from retraction pockets
368
Most pars tensa cholesteatomas arise from?
posterosuperior retractions
369
MC segment of the ossicular chain eroded by both varieties of acquired cholesteatoma
long process of the incus (limited ligamentous support and poor blood supply)
370
MC site of labyrinthine fistula which is a potentially serious complication of cholesteatoma
lateral semicicular canal (most commonly compromised region) > superior ampullar > posterior canal > promontory of the cochlea
371
MC common site of facial nerve compression in cholesteatoma
tympanic segment (w/c lies inferior to the lateral semicircular canal in the middle ear)
372
MC radiographically identified abnormality of the petrous apex
simple effusion
373
3 mc expansile lesions to arise within the petrous apex
cholesterol granuloma (cholesterol cyst), cholesteatoma, mucocele (rare)
374
MC primary petrous apex lesion
cholesterol cyst
375
MCC of labyrinthitis
viral infection
376
MCC of delayed hydrops syndrome
viral labyrinthitis
377
Most widely recognized prenatal viral infections associated w/ perinatal complications including hearing loss
CMV and rubella
378
MCC of labyrinthitis ossificans
suppurative bacterial labyrinthitis
379
MC location for fibrosis and new bone formation in the cochlea
basal turn region of the scala tympani near the round window
380
Pathology most commonly confused w/ necrotizing external otitis
malignancy
381
MC histologies of malignancies involving the EAC
squamous cell and basal cell ca and minor salivary gland ca
382
MC benign neoplasm of the external canal
exostosis
383
Damage to the sound-conducting mechanism of the middle ear is most likely caused by?
chronic otitis media, cholesteatoma, trauma, or congenital ossicular malformation
384
MC ossicular reconstruction and is peformed to restore conductive hearing loss in individuals with fenestral otosclerotis or congenital abnormalities
stapes prosthesis
385
Narrowest point in the facial nerve canal
labyrinthine segment
386
Insult to the facial nerve in what region is the most likely cause of paralysis?
labyrinthine segment
387
Most vulnerable segment of the facial nerve
labyrinthine segment
388
MC locations of tumors presenting as facial paralysis
temporal bone and parotid gland region
389
MC sites of perilymphatic fistula
oval window and round window
390
Excluding Bell's palsy, MCC of facial nerve dysfunction
trauma
391
MCC if conductive hearing loss
impingement of abnormal bone on the stapes footplate (it's this oval window involvement that is the basis of the name fenestral otosclerosis)
392
Location of the MC lesion of otosclerosis
bone just anterior to the oval window, at the location of the embryologic fissula antefenestram
393
MC pattern of FD according to radiologic findings throughout the entire skeletal system
pagetoid
394
In the temporal bone, FD is almost always of the ___ form
sclerotic
395
MC CT findings of temporal bone lesions of FD
increase in bone thickness, homogeneous radiodensity, and a loss of the trabecular pattern
396
Most commonly involved bone in the disseminated polyostotic form of Paget's
pelvis
397
MC and mildest form of osteogenesis imperfecta
type I (previously called osteogenesis imperfecta tarda) - decreased production of type I collagen
398
Most severe form of osteogenesis imperfecta
type II (previously called osteogenesis imperfecta congenita)
399
MC tumor assoc w/ the CPA syndrome
acoustic schwannoma
400
4 MC CPA tumors (in adults / older teenagers)
acoustic schwannoma, meningioma, epidermoid cyst/primary cholesteatoma/pearly tumor, nonacoustic posterior fossa schwannoma
401
MCC of CPA tumors in younger children
gliomas
402
Most likely diagnosis if the intensity of a CPA mass is equal to or less than that of gray matter on T2
meningioma
403
MC vascular lesion assoc w/ compressive symptoms of the posterior fossa CNs
vertebrobasilar dolichoectasia
404
MC symptoms in vertebrobasilar dolichoectasia
facial nerve symptoms (hemifacial spasm and facial paralysis) (2nd MC: trigeminal neuralgia)
405
MC hemishperic tumor of the cerebellum
hemangioblastoma and mets in adults; astrocytomas in young adults or children
406
2nd MC tumor involving the temporal bone / MC tumor in the middle ear / MCC of a pulsatile mass w/ conductive hearing loss
paraganglioma
407
MC feeders of paragangliomas
branches of the ascending pharyngeal artery
408
MC location of intraremporal benign vascular tumors
geniculate ganglion region > IAC > least: posterior genu
409
MC tumor from adjacent anatomic structures that may involve the facial nerve by direct extension
jugular foramen paraganglioma
410
MC malignant tumor of the ear / MC malignant tumor of the middle ear (rare)
SCC
411
MC middle ear neoplasm in early childhood (rare)
embryonal rhabdomyosarcoma
412
MC primary malignant neoplasm in the region of the petrous apex
chondrosarcoma (MC histologic subtype: conventional)
413
MC causes of chronic stridor in the infant
congenital laryngeal or tracheal anomalies such as laryngomalacia or tracheomalacia and vocal cord paralysis
414
MC causes if stridor has been present since birth
congenital laryngomalacia, subglottic stenosis, vocal cord paralysis, or vascular ring
415
MCC of stridor in the newborn and infant
laryngomalacia
416
3rd MC congenital laryngeal abnormality / MC lesion requiring tracheotomy in infants <1 yo
congenital subglottic stenosis
417
2nd MCC of stridor in infancy
vocal cord paralysis
418
MCC of vocal cord paralysis in children
brainstem malformations, particularly Chiari II malformation
419
MCC of OSA in children
adenotonsillar hypertrophy
420
MCC of neonatal nasal airway obstruction
mucosal edema secondary to rhinitis
421
MC form of congenital nasal obstruction / MC congenital abnormality of the nasal cavity
choanal atresia / atresia of the posterior nasal cavity (choanae)
422
MC type of laryngocele
external/combined
423
MC location of laryngeal cysts
valleculae and true vocal cords
424
Vascular compression of the trachea is most frequently caused by?
innominate artery
425
MC symptomatic true vascular ring
double aortic arch
426
MC complications of lymphatic malformations
infection and hemorrhage
427
MCC of acute adenotonsillitis and lymphadenopathy due to bacterial causes
group A strep
428
MC site of abscess or cellulitis/adenopathy
peritonsillar space > retrophayngeal and submandibular space
429
MC cultured organisms in neck infections
Strep pyogenes, Stap aureus, and Bacteroides melanogenicus
430
MC inflammatory cause of stridor in young children
croup / laryngotracheobronchitis (MC viral etiologic agent: human parainfluenza virus)
431
Most commonly injured region of the pediatric airway
supraglottis - receives the brunt of exposure to thermal or caustic substances
432
MC location of complications of intubation
glottic or subglottic level
433
MCC of acquired subglottic stenosis
endotracheal intubation
434
MC location of intubation granulation
vocal process of the arytenoid
435
MC location of impaction of esophageal foreign body
at or just below the level of the cricopharyngeus muscle
436
MC benign neoplasm of the larynx in children / 2nd MCC of childhood hoarseness
recurrent respiratory papillomatosis
437
MC location of papillomas
glottic level
438
MC location of recurrent papillomas
subglottic
439
MC presenting symptoms of juvenile nasopharyngeal angiofibroma
unilateral nasal obstruction and recurrent spontaneous epistaxis
440
MC congenital tumors
teratomas
441
2nd MC location for teratomas in early infancy
head and neck
442
MC malignant tumor of the H&N
lymphoma (2nd MC: sarcomas specifically rhabdomyosarcomas)
443
MC soft tissue sarcoma in the pedia / 2nc MC head and neck malignancy in pedia
rhabdomyosarcoma
444
MC tumors of glandular origin in the H&N
thyroid ca and salivary gland malignancies
445
MC epithelial malignancy in the H&N / MC pediatric epithelial ca
NPCA
446
MC type of lymphoma to involve the H&N and is mc in adolescence
lymphoma
447
Most reliable CT / MRI sign of cartilage invasion
demonstration of through-and-through tumor spread
448
MC origin of sinuses, fistulas, and cysts related to the first arch
external auditory canal
449
Anomalies that approach or involve the EAC most commonly terminates at?
junction of the cartilaginous and boy portions of this canal
450
MC type of 2nd BCCs according to Bailey
type II - originates from persistence of cervical sinus of His (technically, combined 2nd, 3rd, and 4th branchial arches
451
MC location of parathyroid cysts or aberrant glands
inferior to the parathyroid gland
452
MC congenital neck mass / MC midline neck mass
TDC
453
MC location of ectopic thyroid tissue
tongue
454
MC form of lymphangioma
cystic hygroma or cystic lymphangioma
455
MC location of fetal cystic hygromas
posterior triangle of the neck
456
Least common form of lymphangioma and has the most diminutive lymphatic channels
capillary or simple lymphangioma (lymphangioma simplex)
457
MC tumors of the head and neck in infancy and childhood
hemangiomas
458
MC vascular malformations to affect the oral cavity
venous malformations
459
Side mostly involved in IJV phlebectasia
right
460
MC form of teratoma
dermoid cyst
461
MC location of dermoid cysts in the oral cavity / MC site for dermoids in the head and neck, after the nose and orbit
floor of the mouth (sublingual, submental, or submandibular)
462
MC site of upper aerodigestive tract tumor most likely to present w/ metastatic adenopathy
Waldeyer's ring
463
MC site of upper aerodigestive tract tumor most likely to present w/ bilateral neck disease and posterior triangle (level V) adenopathy
Waldeyer's ring
464
Most often affected nodes in viral lymphadenitis
occipital nodes
465
3 mc presenting head and neck complaints of AIDS patients / HIV-infected patients
skin lesions such as Kaposi's sarcoma, oropharyngeal symptoms such as candida oropharyngitis or HSV infections, and cervical lymphadenopathy
466
MCC of acute suppurative lymphadenitis
Staph
467
Most commonly affected by tertiary syphilis
CV and CNS
468
MC site of gummas and large necrotic lesions in tertiary syphilis
liver
469
MC manifestation of histoplasmosis (as with most inhaled mycotic pathogens)
subclinical pulmonary manifestation
470
MC opportunistic infection associated w/ AIDS
P. carinii
471
MCC of intracerebral mass lesions in AIDS
Toxoplasma encephalitis
472
Most likely diagnosis when there is cervical adenopathy and multiple parotid LNs
either sarcoidosis or lymphoma
473
MCC of massive LN infarction
lymphoma or metastatic carcinoma
474
Most frequently involved flat bone in Langerhan's cell histiocytosis
skull
475
Regardless of lymph node size, most reliable imaging finding in metastastic disease
presence of central nodal necrosis on contrast-enhanced CT (routinely identified when >3mm)
476
Most reliable imaging finding in metastastic disease on noncontrast MR
variable T2-weighted signal intensity
477
Primary imaging differential diagnosis of central tumor necrosis
fatty hilar metaplasia (almost exclusively at the periphery of node - pronounced lima bean configuration)
478
MC thyroid cancers to metastasize to the cervical lymph nodes
papillary and follicular types
479
MCC of nodal enhancement / increased nodal vascularity
acute infection
480
Nodal calcifications are most commonly seen in patients with?
tuberculosis
481
MC primary head and neck tumor associated with nodal calcifiations / MCC of calcifications within PPS LNs
metastatic papillary thyroid ca
482
Most pliable border of the PPS
medial wall
483
MC deep space abscesses in children
peritonsillar abscess
484
Most infections that results in PPS abscess arise in?
palatine tonsil or pharynx or odontogenic
485
Statistically, the mc masses in the PPS
hyperplastic or metastatic level II LNs
486
MC primary neoplasms to arise in the PPS
those of salivary gland origin (almost all are pleomorphic adenomas)
487
Site of origin of the 2nd mc benign PPS lesion
arise in extraparotid salivary rests in the prestyloid compartment fat (also predominantly pleomorphic adenoma)
488
Account for most malignancies affecting PPS
malignant tumors arising from the pharyngeal mucosal minor salivary glands and NPCA
489
Most commonly affected in malignant peripheral nerve sheath tumors of the head and neck
CNs, large cervical nerves, sympathetic chain, and inferior alveolar nerve
490
MC form of paragangliomas (in the PPS)
glomus vagale tumor - arises from the paraganglionic cells about the nodose ganglion (2nd MC: carotid body tumor; 3rd MC: glomus jugulare)
491
MC type of paragangliomas
carotid body tumors > glomus jugular and glomus vagale
492
Tumors most often embolized preop
glomus jugulare and vagale
493
MC cellular lesions to involve the PPS
NPCA and oropharyngeal ca - adults; rhabdomyosarcomas or lymphomas - children
494
Mets from distant primary tumors to the PPS com most commonly from?
kidney and thyroid gland
495
Most immediately life-threatening of all the masses in the PPS
aneurysm
496
MC reflex cardiovascular syndromes linked to CN IX
carotid sinus syndrome and glossopharyngeal neuralgia-asystole syndrome
497
MC intracranial neoplasm to extend into the PPS
meningioma
498
Most commonly affected muscle in masticator muscle hypertrophy / MC form of masticator hypertrophy
masseter muscles / masseteric hypertrophy
499
MC abnormality in the sublingual glands
ranula (obstructed mucocele)
500
MCC of viral parotitis / MC of all salivary gland diseases
mumps
