Ear Flashcards
Ear
Which portion of the EAM is bony and slightly narrower?
inner 2/3
Ear
EAM
organs/landmark located anterior to the EAM at the TMJ
parotid gland
Ear
EAM
organs/landmark located posterior to the EAM at the TMJ
mastoid process
Ear
EAM
organs/landmark located inferior to the EAM
jugular bulb
facial nerve
Ear
Which is TRUE regarding the EAM?
I. The lining of the entire auditory canal is continuous with that of the auricle.
II. the outer 2/3 contains hair follicales and sebaceous and ceruminous glands.
I only.
***
It’s outer 1/3 not outer 2/3
Ear
What is the epithelial lining of the tympanic membrane?
squamous
Ear
What is the epithelial lining of the eustachian tube?
stratified columnar
Ear
The inner ear has no lympahatics.
TRUE or FALSE?
True.
Ear
The posterior and superior aspects of the auricle drain into the retroauricular lymph
nodes, and the lobule drains into the superficial cervical group of lymph nodes.
Where do the lymphatics of the tragus and anterior portion of the auricle drain?
superficial parotid nodes.
Ear
More women than men have middle ear tumors, but more men have tumors of the external ear.
TRUE or FALSE?
True.
Ear
What is a common tumor of the external ear that presents as small ulcerations, mostly on the helix?
BCC
Ear
Arrange the following nodes according to the highest frequency of involvement in SCC of the external ear.
parotid
upper deep cervical
postauricular
AS IS
Ear
This imaging modality can show abnormal soft tissue, soft tissue enhancement, and distortion of the normal
tissue planes. Most importantly, when evaluating EAC tumor, it can provide
accurate prediction of bone erosion, such as wall of the EAC, middle ear, TMJ,
carotid artery canal, and jugular fossa and thus can help to determine the
extension and the operability of tumors.
CT
Ear
A bone scan is usually routinely recommended to determine changes in the temporal bone around the tumor.
TRUE or FALSE?
False.
***
it provides
very nonspecific information and is not a recommended method of evaluation
Ear
What type of tumors comprises 85% of auditory canal, middle ear, and mastoid involvement?
SCC
Ear
Endolymphatic sac tumor or aggressive papillary middle ear
tumors are distinct from middle ear adenomas and are rarely aggressive. They are
characterized by slow growth. Extensive local invasion and bone destruction are very rare.
TRUE or FALSE?
False.
They are agressive tumors
Ear
Lesions of the _____ ear are usually more easily controlled
and are usually diagnosed earlier than are lesions on the other sites.
External
Ear
____ cranial nerve palsy associated with middle ear
tumors indicates poor survival showed in pooled-data survival analysis, and have
been adopted into staging system.
Seventh (7th)
CN VII
Ear
Spread of tumors to the lymph nodes usually
indicates a poor prognosis because this is often a late event in the natural history
of the disease.
TRUE or FALSE?
True.
Ear
Pittsburgh Tumor Staging of the EAC.
Tumor eroding the osseous EAC (full thickness) with limited (<0.5 cm) soft tissue
involvement
T3
Ear
Pittsburgh Tumor Staging of the EAC.
Tumor eroding the osseous EAC (not thickness) with limited (<0.5 cm) soft tissue
involvement
T2
Ear
Pittsburgh Tumor Staging of the EAC.
Tumor involving the middle ear and/or mastoid.
T3
Ear
Pittsburgh Tumor Staging of the EAC.
Tumor with extensive soft tissue involvement (>0.5 cm)
T4
Ear
Pittsburgh Tumor Staging of the EAC.
Tumor eroding the cochlea, petrous apex, medial wall of the middle ear, carotid canal,
jugular foramen, or dura, or with extensive soft tissue involvement (>0.5 cm), such as
involvement of TMJ or styloid process, or evidence of facial paresis
T4
Ear
Pittsburgh Tumor Staging of the EAC.
Tumor limited to the EAC without bony erosion or evidence of soft tissue involvement
T1
Ear
AJCC staging
Tumor >2 cm in greatest dimension or tumor any size with two or more high-risk
features
T2
Ear
What are the high-risk features in the AJCC staging?
> 2-mm thickness
Clark level ≥ IV
PNI
anatomic primary on ear or hair-bearing lip
poorly diff/undiff
Ear
Management: External Ear
Treatment of draining lymphatics is normally not required for early stages of
external ear tumors.
TRUE or FALSE?
True.
Afzelius et al. indicate that lesions >4 cm and those with
cartilage invasion have an increased risk of nodal spread; they recommend
prophylactic neck dissection.
Most investigators do not agree with this
approach because the overall chance of lymph node involvement in tumors of
the external ear is only 16%.
Ear
Management: External Ear
Radical surgery followed by postoperative radiation therapy is an acceptable method of treatment for more advanced lesions of the external auditory canal and lesions in the middle ear and mastoid.
Pfreundner et al. recommended a postoperative radiotherapy dose of __to__ Gy for patients with negative margins.
Positive margins warrant higher doses of __ Gy because of higher recurrence rates.
Except in tumors that are detected early, neither modality alone is considered optimal, and a combination of the two produces the best results.
54 to 60
66
Ear
Management: EAC and middle ear
What is the treatment for outer EAC tumor with no invasion of the mastoid?
local excision with at least 1-cm margin between the lesion and TM.
+/- split-thickness skin graft
Ear
Management: EAC and middle ear
What is the treatment if EAC tumor involves the bony canal with impingement of the TM?
surgery.
partial temporal bone resection may be necessary.
in this procedure, the auditory canal,
tympanic membrane, malleus, and incus are removed along with the TMJ, and
the defect is grafted with a split-thickness skin graft
+/-RT depending on margin status.
Ear
Management
For RT of lesions of the pinna, what is the usual margins using electrons for “small superficial” tumors?
1 cm
Ear
Management
For RT of lesions of the pinna, what is the usual margins using electrons for “larger tumors” tumors?
2- to 3-cm
encompass the entire pinna or EAC
Ear
Management
What should be the daily dose for the pinna to avoid necrosis?
What is the total dose required to achieve adequate tumor control?
1.8 to 2 Gy
66 Gy
Ear
Management
Large lesions of the EAC are treated with RT and surgery. RT portals should encompass the entire ear and temporal
bone with an adequate margin (3 cm).
The volume treated should always include the
ipsilateral preauricular, postauricular, jugulodigastric subdigastric lymph nodes, and levels II & III cervical nodes.
TRUE or FALSE?
False.
Treating lymphatics beyond the jugulodigastric area is usually not necessary
Ear
Management
In using IMRT for the definitive treatment of advanced external ear or middle ear cancers, what is the GTV?
clinical and radiographic gross disease
Ear
Management
In using IMRT for the definitive treatment of advanced external ear or middle ear cancers, what is the CTV1?
GTV + 0.3 to 0.5 cm margin
Ear
Management
In using IMRT for the definitive treatment of advanced external ear or middle ear cancers, what is the CTV2?
CTV1 + 0.5 to 0.7 margin
\+ nodes preauricular postauricular ipsilateral upper neck (II) parotid gland
Ear
Management
In using IMRT for the definitive treatment of advanced external ear or middle ear cancers, what is the CTV3?
CTV3 for advanced and aggressive disease
contralateral upper neck (II)
ipsilateral middle and lower neck (III and IV)
Ear
Management
In using IMRT for the definitive treatment of advanced external ear or middle ear cancers, what is the dose for CTV1?
66 to 70/ 2 / 33-35
Ear
Management
In using IMRT for the definitive treatment of advanced external ear or middle ear cancers, what is the dose for CTV2?
63/1.8/35
Ear
Management
In using IMRT for the definitive treatment of advanced external ear or middle ear cancers, what is the dose for CTV3?
56/1.6/35
Ear
Management
In using IMRT for the postoperative treatment of advanced external ear or middle ear cancers, what is the CTV1?
(Chen et al.)
CTV1 includes the original tumor region, surgical bed, soft tissue invasion, areas with positive residual disease, or positive margins to a dose of 60 to 66 Gy at 2 Gy per fraction.
Ear
What should be the dose limit for the cochlea when using conventionally fractionated RT to reduce SNHL?
45 Gy mean dose
or more conservatively at 35 Gy
Ear
What should be the dose limit for the temporal bone when using conventionally fractionated RT to reduce ORN?
70 Gy
