Daily Dose ENT

2016-11-18T12:20:00.004-08:00

Daily Dose ENT is now "Daily ENT".

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1/10/2013

2014-01-10T14:04:00.000-08:00

1/10/2014

Answers:

What percentage of vestibular schwannoma patients have neurofibromatosis type 2?
A)3%
B) 15%
C) 50%
D) 85%
E) 97%

Patients w/ NF2 represent about 2-4% of VS cases.

The NF2 gene encodes what protein? What is the function of this protein?

NF2 encodes for the protein "merlin" which has functions involved with linking cytoskeletal components in the plasma membrane and in contact inhibition.

MC Questions:
Which of the following is not characteristic of the Wishart subtype of NF2?
A) Larger tumors
B) Faster growing tumors
C) Multiple tumors
D) Hearing loss is related to tumor size
E) Later age of onset of disease

Free Response Question:
Describe the difference in the presence of skin neurofibromas between NF1 and NF2.

Quick Facts:

1/9/2014

2014-01-09T14:01:00.000-08:00

1/9/2014

Answers:

What is the most common extra-axial malignant neoplasm of the CPA?
A) Astrocytoma
B) Chordoma
C) Glomus Jugulare
D) Chondrosarcoma
E) Metastases

Mets are the most common extra-axial malignant neoplasm of the CPA.

What is "Meckel's Cave"?

Meckel's Cave, aka trigeminal cave, is an arachnoid pouch w/ CSF in it. It is formed by two layers of dura which are part of an evagination of the tentorium cerebelli near the apex of the petrous part of the temporal bone and envelops CN V. Its boundaries are: the cerebellar tentorium, the lateral wall of the cavernous sinus, the clivus and the posterior petrous face.

MC Questions:
What percentage of vestibular schwannoma patients have neurofibromatosis type 2?
A)3%
B) 15%
C) 50%
D) 85%
E) 97%

Free Response Question:
The NF2 gene encodes what protein? What is the function of this protein?

Quick Facts:
Clinical Findings
Gardner Subtype:
-early onset
-smaller tumors
-few tumors
-slower growing tumors
-hearing loss related to tumor size
Wishart Subtype:
-Later onset
-Larger tumors
-Multiple tumors
-Faster growing tumors
-Hearing loss not related to tumor size
-Usually present in 20-30s, rarely after 60.
-50% of patients present with hearing loss, it is usually progressive and associated
w/ poor speech discrimination scores.
-10% have tinnitus
-acute vertigo is uncommon due to slow growth pattern
-Skin tumors present in 2/3rds of patient as are Cafe-au-lait spots however there are
fewer than six of these (unlike in NF1)
-Juvenile posterior subcapsular lenticular opacities are common (up to 51%). Some are congenital and can be useful in diagnosis.

1/8/2013

2014-01-08T13:58:00.000-08:00

1/8/2014

Answers:

What percentage of CPA tumors are not vestibular schwannomas?
A) 5%
B) 20%
C) 50%
D) 80%
E) 95%

20% of CPA tumors are not schwannomas. Of these ~50% are meningiomas.

What factors should prompt testing for NF2 in a patient who presents w/ a CPA tumor?

If meningiomas are present in a young patient or there are multiple meningiomas, then NF2 testing should be considered.

MC Questions:
What is the most common extra-axial malignant neoplasm of the CPA?
A) Astrocytoma
B) Chordoma
C) Glomus Jugulare
D) Chondrosarcoma
E) Metastases

Free Response Question:
What is "Meckel's Cave"?

Quick Facts:
Neurofibromatosis Type 2
-Hallmark is b/l vestibular schwannomas.
-often confused with von Recklinghausen syndrome, however this is peripheral
neurofibromatosis and is designated NF1.
-NF2 is much more rare compared to NF1 (1:50,000)
-NF2 is autosomal dominant w/ 95% gene penetrance.
-presents in 2-3rd decade.
-Pts w/ NF2 represent 2-4% of VS.
-NF2 gene encodes for protein called merlin which functions as a membrane-organizing protein.
Pathogenesis
-from inheritance of mutation in merlin protein on chromosome 22.
-Merlin involved in linking cytoskeletal components w/ plasma membrane.
-Loss of this protein could lead to loss of contact inhibition.
-50% of patients have no family hx and are likely new germ line mutations.
-NF2 mutations associated w/ protein truncation are more severe = Wishart
type
-NF2 mutations associated w/ protein missense or splicing are milder = Gardner
type

1/7/2013

2014-01-07T13:54:00.000-08:00

1/7/2014

Answers:

Which of the following approaches to a CPA tumor is hearing ablative?
A) Retrosigmoid
B) Middle Fossa
C) Translabyrinthine
D) They can all be hearing preserving as long as care is taken not to damage vital hearing structures
E) They are all hearing ablative

The translabyrinthine approach is hearing ablative whereas the retrosigmoid and middle fossa approaches can keep hearing intact.

When is observation an adequate management strategy for vestibular schwannomas?

Observation is reasonable in older patients or in pts where the tumor does not appear to be growing significantly.

MC Questions:
What percentage of CPA tumors are not vestibular schwannomas?
A) 5%
B) 20%
C) 50%
D) 80%
E) 95%

Free Response Question:
What factors should prompt testing for NF2 in a patient who presents w/ a CPA tumor?

Quick Facts:
Treatment of CPA meningiomas
-can observe or use stereotactic radiotherapy if pt has limited life expectancy or not surgical candidate, otherwise treat w/ surgery.
-ideal surgery consists of total meningioma removal and excision of surrounding dura w/ drilling of underlying bone.
-Surgical approach depends on location of tumor and pts hearing.
-Meningiomas medial to the IAC are more common.
-arise along inferior petrosal sinus and involve petrous apex, lateral clivus and meckel cave.
-Meningiomas lateral to IAC involve the sigmoid sinus, jugular bulb and superior petrosal sinus.
-Approach these via retrosigmoidal approach as facial nerve is often displaced anteriorly so a retro sigmoid approach does not place the nerve between the surgeon dn the tumor. Also allows for hearing preservation.
-Limited intracanalicular meningiomas can be managed by middle cranial fossa approach to preserve hearing or translabyrinthine if pt has poor/no hearing.
-If meningioma invades cochlear or extends to clivus or meckle cave than transcochlear approach is warranted.
-60% of CPA meningiomas involve middle fossa and may need craniotomy of combine middle/posterior fossae.
Prognosis
-Total tumor removal achieved in 70-85% of cases.
-Non total removal often due to adherence to brainstem or cavernous sinus involvement.
-Long term recurrence is 10-30% if all removed, 50% if some left behind.
-Hearing preservation is ~70% (more than schwannomas)

1/6/2014

2014-01-06T13:52:00.000-08:00

1/6/2014

Answers:

What is the average growth rate of vestibular schwannomas?
A) 0.5 mm/yr
B) 1mm/yr
C) 1.2 mm/yr
D) 1.5 mm/yr
E) 1.8mm/yr

The average growth of VS is 1.8/yr. However, this can vary widely and a repeat scan should be performed 6 months after initial diagnoses to assess the growth pattern of each particular tumor.

Typically, how large must a CPA tumor be to cause cerebellar symptoms?

To cause cerebellar symptoms a VS usually has to fill the CPA which requires it to be ~ 3cm.

MC Questions:
Which of the following approaches to a CPA tumor is hearing ablative?
A) Retrosigmoid
B) Middle Fossa
C) Translabyrinthine
D) They can all be hearing preserving as long as care is taken not to damage vital hearing structures
E) They are all hearing ablative

Free Response Question:
When is observation an adequate management strategy for vestibular schwannomas?

Quick Facts:
Vestibular Schwannomas = 80% of CPA tumors.
-Of the other 20%, most are distinguished be imaging characteristics
-CPA: Bounded be temporal bone, cerebellum and brainstem
-CPA is traversed be CN V-XI.
-90% of CPA tumors are schwannomas and meningiomas, the other 10% include congenital rest lesions, intra-axial tumors, metastases and vascular lesions and lesions from skull base.
-Classic symptoms of CPA tumors include : unilateral hearing loss, vertigo, altered facial sensation, facial pain progressing to nystagmus, facial palsy, vocal cord palsy, dysphagia, diplopia, respiratory compromise and death.

1/3/2014

2014-01-03T13:49:00.000-08:00

1/3/2014

Answers:

What is the best study to diagnose a vestibular schwannoma.
A) MRI w/o contrast
B) MRI w/ contrast
C) CT w/ contrast
D) CT w/o contrast
E) Angiogram

The gold standard for VS diagnosis is MRI w/ gadolinium contrast

What is the definition of "rollover"?

Rollover = Retrocochlear
pathology causes WRS to be lower than expected based on pure-tones. Often this WRS gets worse with increasing intensity of sound.

MC Questions:
What is the average growth rate of vestibular schwannomas?
A) 0.5 mm/yr
B) 1mm/yr
C) 1.2 mm/yr
D) 1.5 mm/yr
E) 1.8mm/yr

Free Response Question:
Typically, how large must a CPA tumor be to cause cerebellar symptoms?

Quick Facts:
Surgical Measures for vestibular schwannomas
-Approach is based on hearing status, size of tumor and extent of IAC
involvement.
-Can be hearing preserving(retrosigmoid/middle fossa) or ablative
(translabyrinthine).
-Middle fossa = good hearing pt and tumor <1.5cm in CPA.
-Retrosigmoid = good hearing pt w/ tumor <4 cm not involving lateral IAC.

1/2/2014

2014-01-02T15:05:00.000-08:00

1/2/2014

Answers:

Rank the following complaints on presentation of vestibular schwannoma from most common to least common.
A) V2 Dysfunction > Hearing Loss > Tinnitus > Diplopia
B) Tinnitus > Hearing Loss > Diplopia > V2 Dysfunction
C) Hearing Loss > Tinnitus > Diplopia > V2 Dysfunction
D) Tinnitus > Hearing Loss > V2 Dysfunction > Diplopia
E) Hearing Loss > Tinnitus > V2 dysfunction > Diplopia

95% of VS present w/ unilateral hearing loss. 65% will present with tinnitus. Facial/Trigeminal dysfunction is another common presentation for VS. Diplopia is an unusual in early VS and is not a common presenting symptom.

The IAC is divided into 4 quadrants by what two structures?

The "transverse crest" and the "vertical crest" (aka Bill's bar)

MC Questions:
What is the best study to diagnose a vestibular schwannoma.
A) MRI w/o contrast
B) MRI w/ contrast
C) CT w/ contrast
D) CT w/o contrast
E) Angiogram

Free Response Question:
What is the definition of "rollover"?

Quick Facts:
-Natural hx of VS includes a slow growth in the IAC and then into the cisterna of the
CPA.
-Average growth rate is 1.8 mm/yr.
-Symptom onset is often slow/insidious but predictable.
-Occasional rapid progression can occur due to cystic degeneration or bleeding.
-Initial growth often affects vestibulocochlear nerve in rigid IAC causing unilateral
hearing loss, tinnitus and vertigo.
-Tumor then progresses to CPA cistern and grows freely w/o symptoms until it reaches 3 cm.
-At this point corneal/mid face numbness, further hearing loss, vertigo and facial
weakness/spasms can occur.
-Further growth causes cerebellar signs including ocular changes, headache, AMS, n/v and eventually death.

1/1/2014

2014-01-01T14:54:00.000-08:00

1/1/2014

Answers:

What is the most common type of CPA tumor?
A) Epidermoid
B) Glomus
C) Meningioma
D) Astrocytoma
E) Schwannoma

80% of CPA tumors are vestibular schwannomas (aka acoustic neuromas)

Describe the boundaries of the CPA.

-Superior boundary = tentorium

-inferior boundary = cerebellar tonsil / medullary olives

-anterior border = posterior dural surface of petrous bone and clivus

-posterior border = ventral surface of pons/cerebellum

-medial border = cisterns of pons and medulla

-apex = region of the lateral recess of the fourth ventricle.

MC Questions:
Rank the following complaints on presentation of vestibular schwannoma from most common to least common.
A) V2 Dysfunction > Hearing Loss > Tinnitus > Diplopia
B) Tinnitus > Hearing Loss > Diplopia > V2 Dysfunction
C) Hearing Loss > Tinnitus > Diplopia > V2 Dysfunction
D) Tinnitus > Hearing Loss > V2 Dysfunction > Diplopia
E) Hearing Loss > Tinnitus > V2 dysfunction > Diplopia

Free Response Question:
The IAC is divided into 4 quadrants by what two structures?

Quick Facts:
Imaging for Vestibular Schwannomas
-gold standard is MRI w/ gadolinium contrast
-can differentiate various CPA tumors on MRI.
-VS are hypointense globular mass centered over IAC on T1 w/ enhancement w/
gadolinium. They are iso-to hypointense on T2.
Special Tests
-Average pt requires 4 years from onset of symptoms to diagnosis of VS.
-Pts w/ unilateral auditory, vestibular and facial complaints need to undergo eval to
r/o retrocochlear disease.
-Pure-tone audiograms in VSD patients show asymmetric, downsloping, high frequency SNHL in 70%.
-Retrocochlear pathology causes WRS to be lower than expected based on pure-tones. Often this WRS gets worse with increasing intensity of sound = Rollover.
-Abnormal WRs should prompt imaging.

12/31/2013

2013-12-31T14:42:00.000-08:00

12/31/2013

Answers:

What percentage of traumatic TM perforations heal within 30 days?
A) 20%
B) 50%
C) 70%
D) 90%
E) 100%

~70% of traumatic TM perfs heal on their own in one month. ~95% will heal within 3 months. If a TM perf is still not healed on its own after this time consider performing a paper-patch myringoplasty.

After what length of time dose persistence of a posttraumatic CSF leak significantly raise the chance of developing meningitis?

80% of CSF leaks will close on their own within a week and the risk of meningitis is low, however, CSF leaks that persist longer than 7-10 days the risk of developing meningitis increases dramatically to >20%.

MC Questions:
What is the most common type of CPA tumor?
A) Epidermoid
B) Glomus
C) Meningioma
D) Astrocytoma
E) Schwannoma

Free Response Question:
Describe the boundaries of the CPA.

Quick Facts:
Clinical
Findings Of Vestibular Schwannoma -Hearing
loss present in 95% of patients.-Mostly
slowly progressive hearing loss w/ noise distortion.-20%
have episodes of sudden hearing loss.-Level
of hearing loss does not predict tumor size.
-Tinnitus
present in 65% of patient, often constant high pitch buzzing.-Pts
often adapt to disequilibrium well because it occurs so slowly but it is present
in 60% of patients.
-Facial/Trigeminal
nerve dysfunction-most
common to see V2 numbness/absent corneal reflex.-can
also see numbness of posterior EAC (Hitselberger sign-Facial
weakness only present in 17%
-Other
complaints include visual complaints, diplopia, headache, AMS, n/v and increased
ICP w/ papilledema however these occur only during rapid expansion.

12/30/2013

2013-12-30T14:32:00.000-08:00

12/30/2013

Answers:

What percentage of transverse temporal bone fractures cause a facial nerve injury?
A) 10%
B) 25%
C) 50%
D) 75%
E) 90%

Facial nerve injury is present in 50% of transverse tbone fractures. Facial nerve injury is present in only 20% of longitudinal t bone fractures. It is always import to delineate whether facial nerve injuries are immediate or delayed as immediate are almost always operative, wheres delayed is usually not.

What test can be done to determine whether clear fluid draining from the ear is CSF or simply rhinorrhea from rhinitis?

B2 Transferrin is the test of choice to confirm the presence of CSF. B2 transferring is a protein found exclusively in CSF.

MC Questions:
What percentage of traumatic TM perforations heal within 30 days?
A) 20%
B) 50%
C) 70%
D) 90%
E) 100%

Free Response Question:
After what length of time dose persistence of a posttraumatic CSF leak significantly raise the chance of developing meningitis?

Quick Facts:
-CPA = potential CSF filled space in posterior cranial fossa bounded be temporal
bone, cerebellum and brainstem.-triangle
shaped,-Superior
boundary = tentorium-inferior
boundary = cerebellar tonsil / medullary olives-anterior
border = posterior dural surface of petrous bone and clivus-posterior
border = ventral surface of pons/cerebellum-medial
border = cisterns of pons and medulla-apex
= region of the lateral recess of the fourth ventricle.-The
lateral opening of the fourth ventricle (foramen of luschka) opens into
CPA.-CN
V-XI traverse cephalic and caudal extent of CPA.-Transition
to peripheral myelin (made by schwann cells) occurs at the medial opening of the
IAC.

12/27/2013

2013-12-27T18:21:00.000-08:00

12/27/2013

Answers:

Diagnose this fracture.

A) Mastoid fracture
B) Transverse Temporal bone fracture
C) Longitudinal Temporal Bone Fracture
D) Occipital Bone fracture

This is a classic longitudinal temporal bone fracture extending along the EAC and ending near the foramen lacerum.

After a temporal bone fracture, what degree of delayed facial nerve degeneration is required in order to benefit from surgical decompression.

Patients with delayed facial nerve paralysis who are found to have > 90% degeneration of the nerve on nerve excitability or electroneuronography testing (which cannot be done until at least 3 days post injury) may benefit from surgical decompression. This is controversial however. Patients with <90% degeneration should not be operated on as they are likely to have full and spontaneous recoveries.

MC Questions:
What percentage of transverse temporal bone fractures cause a facial nerve injury?
A) 10%
B) 25%
C) 50%
D) 75%
E) 90%

Free Response Question:
What test can be done to determine whether clear fluid draining from the ear is CSF or simply rhinorrhea from rhinitis?

Quick Facts:
Treatment of Temporal Bone Fracture Complications

-Conductive Hearing Loss:
-Hemotympanum resolves on its own within 3-4 weeks of the injury.
-Traumatic TM perfs heal well on their own, 68% in 1 months, 94% in 3 months. If
not healed be 3 months can perform paper-patch myringoplasty. (can only do if TM
is <25% and does not involve margin and middle ear mucosa
uninfected/dry)
-Freshen edges of perf w/ Rosen needle (Husseman dose this w/ TCA (some type of
acid) then place paper over hole and bacitracin over paper.
-If perf is large or paper-patch has failed then pt can go to OR for standard
tympanoplasty.

-Facial Nerve Paralysis:
-Mostly conservative treatment for delayed onset palsy (94% recover
fully).
-If pt has >90% degeneration of facial nerve function then recovery is much
worse, likely due to nerve swelling within bony fallopian canal. Management is
controversial.
-Some recommend watchful waiting, other recommend decompression.
-Immediate onset facial nerve palsy should undergo nerve exploration
ASAP.
-If pt has normal hearing a combined middle fossa/transmastoid facial nerve
exploration can be done including subtemporal craniotomy w/ delineation of the
facial nerve within IAC from porus acusticus internus to geniculate ganglion.
-If patient has complete SNHL then translabyrinthine facial nerve exploration
can be done, allows for complete exposure to facial nerve from porus acousticus
to stylomastoid foramen.
-Injuries are most commonly located in the area of the geniculate ganglion.
-If intraneural hematoma appreciated then epineurium should be carefully opened
and hematoma evacuated.
-Remove any bony fragments.
-If obvious fracture of nerve then freshen both ends an anastomosis. If to long
to anastomose w/o tension then interposition nerve graft from greater auricular
or sural nerve can by done.

-CSF Leak and Encephalocele
-80% of posttraumatic CSF leaks close spontaneously after 7 days and risk of
meningitis is low so treat medically at first.
-Med treatment = HOB elevated, stool softeners, acetazolamide (decreases CSF
production) and lumbar drain. Short to abx can decrease meningitis rates.
-Most common organisms for meningitis in these cases are pneumococcus, staph,
strep and H. flu.
-If CSF leak persists 7-10 dys risk of meningitis increases to >20% and surgical repair is needed.
-Most common after transverse tbone fx involving otic capsule as otic capsule
does not heal w/ new bone formation but be fibrous union which is not strong
enough to contain CSF.
-An encephalocele should always be surgically repaired.

12/26/2013

2013-12-26T18:17:00.000-08:00

12/26/2013

Answers:

Blows to the lateral side of the skull often result in --- fx of t-bone whereas blunt trauma to the occipital skull result in --- fx of t-bone.
A) Longitudinal, Transverse
B) Longitudinal, Vertical
C) Transverse, Vertical
D) Transverse, Longitudinal
E) Vertical, Longitudinal

What is the most common type of temporal bone fracture?

Longitudinal fractures comprise 80% of tbone fractures. Transverse fracturse comprise 20%. However, transverse fractures are more likely to involve the otic capsule.

MC Questions:
Diagnose this fracture.

A) Mastoid fracture
B) Transverse Temporal bone fracture
C) Longitudinal Temporal Bone Fracture
D) Occipital Bone fracture

Free Response Question:
After a temporal bone fracture, what degree of delayed facial nerve degeneration is required in order to benefit from surgical decompression.

Quick Facts:
Complications of Temporal Bone Fractures

-Conductive Hearing Loss:
-most commonly from hemotympanum but also TM perf or ossicular
discontinuity.
-Most common OD is incudostapedial joint dislocation.
-Ossicular fixation can occur several months after trauma if new bone formation
at the line of the fx fuses to the ossicular chain.

-Sensorineural Hearing Loss and Vertigo
-In transverse temporal bone fxs w/ otic capsule involvement.
-Pneumolabyrinth is often noted on CT.
-Audiogram shows complete SNHL in affected ear.
-Clinical exam reveals nystagmus
-Can get SNHL w/o otic capsule involvement if labyrinthine concussion, traumatic
noise exposure or blast occurs. THought to be due to testing of the cochlear
membrane and/or trauma to hair cell epithelium due to rapid acceleration and
deceleration forces in the inner ear.-Facial

-Nerve Injury:
-Occurs in 20% of longitudinal and 50% of transverse fxs.
-Important to delineate whether facial nerve injury was immediate or delayed.
-Delayed present w/ normal function that worsens slowly over hours-days.
-Likely from edema within facial nerve without disruption of neural integrity.
-Immediate facial nerve palsy likely due to nerve transection

-Cerebrospinal Fluid Leak
-2% incidence of CSF leak in all skull fxs, 20% in Tbone fxs.
-Usually occurs within first 48 hrs.
-Clear fluid from ear/nose. Worse with straining, standing up, bending over.
-Can collect and send of B2 transferrin testing.

Posttraumatic Encephalocele
-Can result if large defect in floor of the middle cranial fossa occurs.
-Dura and temporal lob can herniate down into middle ear.

12/25/2013

2013-12-25T18:13:00.000-08:00

12/25/2013

Answers:

A patient presents saying they stuck a bobby pin deep in their left ear to "clean it out" when they felt a pop and suddenly had hearing loss on that side. On exam the patient lateralizes weber to the right and demonstrates some nystagmus. What is the most likely diagnosis?
A) Ossicular Discontinuity
B) Stapes subluxation
C) Tympanic Membrane Perforation
D) EAC laceration
E) None of the above

Although this patient also has a TM perf her weber lateralizes to the wrong side as it should lateralize to the side of a CHL. Additionally, her nystagmus is concerning for stapes subluxation and perilymphatic fistula which should be urgently treated.

What is the maximum hearing loss caused solely by ossicular chain dislocation?

60 dB is the maximum hearing loss from OCD (or any CHL)

MC Questions:
Blows to the lateral side of the skull often result in --- fx of t-bone whereas blunt trauma to the occipital skull result in --- fx of t-bone.
A) Longitudinal, Transverse
B) Longitudinal, Vertical
C) Transverse, Vertical
D) Transverse, Longitudinal
E) Vertical, Longitudinal

Free Response Question:
What is the most common type of temporal bone fracture?

Quick Facts:
Special Tests for Tbone fxs
-Audiometry should be done on all pts as an outpatient usually after hemotympanum has resolved (several weeks).
-If otic capsule fx then very likely there will be complete SNHL.
-Consider urgent audiometry if stapes subluxation into vestibule has occured.
-Facial nerve testing should be done if delayed, complete facial palsy occurs.
-Pts w/ >90% degeneration of facial nerve have poorer recovery and benefit
from surgical decompression.
-Nerve excitability test = place two probes of Hilger nerve stimulators across
the stylomastoid foramen and turn up until facial twitch barely visible...a
3.5mA difference between the injured and uninjured sides correlates with a
>90% loss of neural integrity.
-Electroneuronography can by done by a neurophysiologist = stimulating both
facial nerves with equal current and measuring myogenic potential.
-Neither test is accurate within 3 days of injury as it takes 72 hrs for nerve
fibers distal to site of injury to degenerate.

12/24/2013

2013-12-24T18:07:00.000-08:00

12/24/2013

Answers:

Fluid lights up on --- and is dark on ---- MRIs.
A) T1; T2 weighted
B) T2; T1 weighted

Think "black and white TV = T1 and T2 weighted MRI"

What is the dB difference required for Weber to lateralize?
What is the dB difference required for Rinne to demonstrate BC>AC?

5 dB for Weber to lateralize. 25 dB for Rinne to be negative (i.e. BC>AC).

MC Questions:
A patient presents saying they stuck a bobby pin deep in their left ear to "clean it out" when they felt a pop and suddenly had hearing loss on that side. On exam the patient lateralizes weber to the right and demonstrates some nystagmus. What is the most likely diagnosis?
A) Ossicular Discontinuity
B) Stapes subluxation
C) Tympanic Membrane Perforation
D) EAC laceration
E) None of the above

Free Response Question:
What is the maximum hearing loss caused solely by ossicular chain dislocation?

Quick Facts:
Temporal Bone Fractures
-Skull base includes frontal, sphenoid, temporal and occipital bones. Fx of skull base involves 1+ of these.
-20% of skull fx involve Tbone, risk factors = male and under 21.
-Blunt trauma to lateral side of skull often = longitudinal fx.
-Blow to occipital skull may = transverse fx.Pathogenesis
-Longitudinal fx involve squamous portion of Tbone.
-They follow the axis of EAC to middle ear the course ant along geniculate ganglion
and eustachian tube ending near foramen lacerum.
-Otic capsule is spared.
-Transverse fx course directly across petrous pyramid, fx otic capsule, and extend
anteriorly along eustachian tube and geniculate ganglion.
-Longitudinal = 80%, Transverse = 20%
Clinical Findings
-hearing loss, n/v/vertigo.
-Battle sign = postauricular ecchymosis (due to extravasation of blood from
postauricular artery (or mastoid emissary vein).
-”Raccoon” sign = periorbital ecchymosis = associated w/ basilar skull fx involving
middle/anterior cranial fossa.
-May see EAC laceration w/ bony debris
-Usually has hemotympanum.
-May see CSF otorrhea or rhinorrhea.
-Also do tuning for test, weber lateralizes to fx ear if CHl present and contralateral
is snhl present.
-Always document facial nerve function.

12/23/2013

2013-12-23T18:04:00.000-08:00

12/23/2013

Answers:

What branch of the external carotid artery is most likely to feed a carotid body tumor?
A) Ascending Pharyngeal
B) Lingual
C) Facial
D) Internal Maxillary
E) Superior Thyroid

The ascending pharyngeal is the artery that supplies carotid body tumors.

What is the likely causes of this patient's hearing loss?

Noise exposure or occupational hearing loss. This audiogram demonstrates the classic "noise notch" that those who experience hearing loss after exposure to hazardous levels of noise show on audiograms.

MC Questions:
Fluid lights up on --- and is dark on ---- MRIs.
A) T1; T2 weighted
B) T2; T1 weighted

Free Response Question:
What is the dB difference required for Weber to lateralize?
What is the dB difference required for Rinne to demonstrate BC>AC?

Quick Facts:
Tympanic Membrane Perforation
-Often due to cotton swabs, bobby pins, pencils, or hot metal (welders).
-Presents with pain + hearing loss.
-Dx w/ otoscopy. Note amount of perf.
-Central perf = does not involve annulus
-Marginal perf = involves annulus.
-Fork pt to confirm CHL, also look for nystagmus
-If pt does not lateralize appropriately and pt has nystagmus = stapes
subluxation w/ perilymphatic fistula which requires urgent treatment.
-Perfs usually heal on their own.
-Pt should follow strict dry ear precautions.
-Perform audiogram in 3 months to confirm hearing return to baseline. If perf has not healed in 3 months, will require tympanoplasty.
Ossicular Chain Dislocation
-Manifests as maximal CHL = 60 db.
-Treat w/ middle ear exploration and ossicular chain reconstruction w/
tympanoplasty.

12/20/2013

2013-12-20T17:55:00.000-08:00

12/20/2013

Answers:

What complication results from damage to the superior laryngeal nerve?
A) Dysphagia
B) Strap muscle motor weakness
C) Aspiration
D) Inability to abduct vocal folds
E) More than one of the above

The superior laryngeal nerve provides sensation to the larynx. A decrease in sensation inhibits coughing and leads to aspiration.

Name the seven branches of the external carotid artery.

The mneumonic is "Some Attendings Like Freaking Out Potential Med Students"

-Superior Thyroid

- Ascending Pharyngeal

- Lingual

- Facial

- Occipital

- Posterior Auricular

- (internal) maxillary

- Superficial temporal

MC Questions:
What branch of the external carotid artery is most likely to feed a carotid body tumor?
A) Ascending Pharyngeal
B) Lingual
C) Facial
D) Internal Maxillary
E) Superior Thyroid

Free Response Question:
What is the likely causes of this patient's hearing loss?

Quick Facts:
Basic MRI scans

T1-weighted MRI
-T1-weighted scans refer to a set of standard scans that depict differences in the spin-lattice (or T1) relaxation time of various tissues within the body. T1 weighted images can be acquired using either spin echo or gradient-echo sequences. T1-weighted contrast can be increased with the application of an inversion recovery RF pulse. Gradient-echo based T1-weighted sequences can be acquired very rapidly because of their ability to use short inter-pulse repetition times (TR). T1-weighted sequences are often collected before and after infusion of T1-shortening MRI contrast agents. In the brain T1-weighted scans provide appreciable contrast between gray and white matter. Water (such as CSF and blood) is dark and white matter is lighter than grey. In the body, T1 weighted scans work well
for differentiating fat from water—with water appearing darker and fat
brighter.

T2-weighted MRI
-T2-weighted scans refer to a set of standard scans that depict differences in the spin-spin (or T2) relaxation time of various tissues within the body. Like the T1-weighted scan, fat is differentiated from water, but in this case fat shows darker, and water lighter. For example, in the case of cerebral and spinal study, the CSF
(cerebrospinal fluid) will be lighter in T2-weighted images. These scans are therefore particularly well suited to imaging edema, with long TE and long TR. Because the spin echo sequence is less susceptible to inhomogeneities in the magnetic field, these images have long been a clinical workhorse.

12/19/2013

2013-12-19T17:34:00.000-08:00

12/19/2013

Answers:

A patient is found to have low frequency CHL and stapedius reflexes that are present. What clinical findings would support the most likely diagnosis?
A) + Fukuda test
B) Vertical Nystagmus
C) Tullio Phenomenon
D) Hennebert Sign
E) More than one of the above is correct

Low frequency CHL w/ + stapedius reflex raises concerns for superior canal dehiscence syndrome which is associated with the Tullio Phenomenon and Hennebert sign.

What is "Alexander's Law"?

Alexander's law states that in individuals with nystagmus, the
amplitude of the nystagmus increases when the eye moves in the direction of the
fast phase (saccade). It is manifested during spontaneous nystagmus in
a patient with a vestibular lesion. The nystagmus
becomes more intense when the patient looks in the quick-phase than in the
slow-phase direction.The law was named after Gustav Alexander who described it in 1912. -wikipedia

MC Questions:
What complication results from damage to the superior laryngeal nerve?
A) Dysphagia
B) Strap muscle motor weakness
C) Aspiration
D) Inability to abduct vocal folds
E) More than one of the above

Free Response Question:
Name the seven branches of the external carotid artery.

Quick Facts:
Occupational Hearing Loss
-Daily exposure to loud noise produces loss of high frequency sensitivity in the 4-6
kHz range = “noise notch”
Pathology
-thought to be due to metabolic depletion of the sensory epithelium of the cochlea
(mainly outer hair cells)
-Can cause temporary threshold shift (TTP, recovers in a few days) or permanent
threshold shift.
Diagnosis
1. Significant exposure to hazardous noise (time weighted average of 90 db)
2. gradual onset hearing loss
3. symmetrical loss
4. hearing loss at ~4000 Hz
5. occupational hearing loss is not progressive after maximum loss incurred
approximately 10-12 yrs after initial exposure.
6. Normal speech discrimination
7. maximum amount of hearing loss caused by occupational noise exposure is 40 db in speech frequencies and 75 db in higher frequencies.
8. occupation hearing loss does not progress once the subject is removed from noisy environment.

12/18/2013

2013-12-18T17:18:00.000-08:00

12/18/2013

Answers:

Vestibular suppressant are useful in treating the symptoms of vestibular neuronitis, however pts are advised to discontinue the use of these medications as soon as tolerable. Why?
A) Use of these drugs decrease central compensation
B) These medications can become addicting
C) Use of these medications has undesirable side effects
D) Use of these medications can make symptoms worse
E) More than one of the above are true

Use of vestibular suppressants and anti emetics over a prolonged period can decrease central vestibular compensation.

Describe the location and significance of "Donaldson's Line".

The vestibular sac is located inferior to the imaginary line “Donaldson line”. This imaginary line is drawn posteriorly from the course of the horizontal semicircular canal. The line should course perpendicular to that of the posterior semicircular canal.

MC Questions:
A patient is found to have low frequency CHL and stapedius reflexes that are present. What clinical findings would support the most likely diagnosis?
A) + Fukuda test
B) Vertical Nystagmus
C) Tullio Phenomenon
D) Hennebert Sign
E) More than one of the above is correct

Free Response Question:
What is "Alexander's Law"?

Quick Facts:
Branches of External Carotid
-Superior Thyroid
- Ascending Pharyngeal
- Lingual
- Facial
- Occipital
- Posterior Auricular
- (internal) maxillary
- Superficial temporal

12/17/2103

2013-12-17T17:09:00.000-08:00

12/17/2013

Answers:

As a treatment for Meniere Disease, intratympanic --- is absorbed into inner ear primarily be ---- window and selectively damages vestibular hair cells.
A) Tobramycin; oval
B) Tobramycin; round
C) Gentamicin; oval
D) Gentamicin; round
E) Amikacin; oval
F) Amikacin; round

Gentamicin is believe to be absorbed primarily through the round window and selectively damage vestibular hair cells. Gentamicin can also decrease endolymph production be affecting dark cells in stria vascularis.

What are the four symptoms of Meniere Disease?

-Unilateral fluctuating SNHL
-Vertigo lasting minutes-hours
-Constant or intermittent tinnitus increasing in intensity before/during
vertiginous attacks.
-Aural fullness

MC Questions:
Vestibular suppressant are useful in treating the symptoms of vestibular neuronitis, however pts are advised to discontinue the use of these medications as soon as tolerable. Why?
A) Use of these drugs decrease central compensation
B) These medications can become addicting
C) Use of these medications has undesirable side effects
D) Use of these medications can make symptoms worse
E) More than one of the above are true

Free Response Question:
Describe the location and significance of "Donaldson's Line".

Quick Facts:
Superior Semicircular Canal Dehiscence
-Described by Lloyd Minor in 1998 = sound/pressure induced vertigo associated w/ bony dehiscence of superior semicircular canal.
-Pts have Tullio phenomenon.
-Also have symptoms w/ Valsalva maneuvers, or pressure changes (Hennebert Sign) or when ICP elevated.
Prognosis
-Due to exposure to external pressure along dehiscent superior canal transmitted to
inner ear.
-1% of temporal CT scans demonstrate significant thinning of this bone. Usually
bilateral.
Clinical Findings
-May be congenital but presentation is usually not until second decade.
-Can present w/ vestibular only, auditory only (rarer) or both.
-Pts report increased sensitivity to bone conduction sounds, hearing their pulse,
hearing their eye movement and autophony.
-”Inner ear conductive hearing loss” is common.
-Hearing loss is artifactual and mimc otosclerosis (low frequency CHL)...however, unlike otosclerosis, stapedius reflexes are present.
-Stapedius reflex w/ low-frequency CHL = imaging of inner ear to r/o dehiscence of the inner ear.
Imaging
-Use 0.5 mm collimated helical CT scans w/ reformation of the images in the plane of the superior canal.
Audio Testing
-low frequency CHL w/ stapedius reflex.
-Presentation of loud auditory signal may elicit typical symptoms of vertigo and eye
movement
Special Exams
-Frenzel glasses can be used, usually follow Ewald Lar.
-Nystagmus is in plane of canal and fast phase is toward stimulated canal.
-Lower than normal threshold for eliciting VEMP response.
Treatment
-Avoid stimulating stimuli.
-Correct diagnosis prevent unnecessary otosclerosis surgery.
-Can be treated w/ tympanostomy tube.
-If severe may require surgical repair of the dehiscence of the superior canal via
middle cranial fossa ro transmastoid approach.
-Symptoms may recur after surgery.
-Hearing loss after surgery is more common after revision.

12/16/2013

2013-12-16T16:58:00.000-08:00

12/16/2013

Answers:

What is the primary treatment of BPPV?
A) Semicircular Canal Occlusion
B) Epley Maneuvers
C) Diuretics
D) Avoiding inciting head positions
E) Vestibular Suppressants

80% of patients have resolution of symptoms with Epley or Semont maneuvers.

What are Ewald's three laws?

Ewald’s three laws:
1. A stimulation of the semicircular canal causes a movement of the eyes in the plane of the stimulated canal
2. In the horizontal semicircular canals, an ampullopetal endolymph movement cases a greater stimulation than an ampullofugal one.
3. In the vertical semicircular canals, the reverse is true.

MC Questions:
As a treatment for Meniere Disease, intratympanic --- is absorbed into inner ear primarily be ---- window and selectively damages vestibular hair cells.
A) Tobramycin; oval
B) Tobramycin; round
C) Gentamicin; oval
D) Gentamicin; round
E) Amikacin; oval
F) Amikacin; round

Free Response Question:
What are the four symptoms of Meniere Disease?

Quick Facts:
Vestibular Neuronitis
-Third most common cause of peripheral vestibular vertigo (after BPPV and
Meniere)
-No gender bias, mostly in middle aged.
-<50% have antecedent viral illness.
-Presents w/ acute vertigo.
-Pathogenesis unknown.
-Treat w/ supportive care, MD job is to r/o central causes of acute vertigo
Pathogenesis
-Unknown
-May by viral infection, vascular occlusion or immunologic.
-Most likely is reactivation of latent HSV
Clinical Findings
-sudden onset vertigo w/ nausea and vomiting.
-normal hearing, normal neuro exam.
-May have postural instability towards injured ear but able to walk w/o
falling.
-No HA, has spontaneous nystagmus similar to acute peripheral vestibular
injury.
-Horizontal w/ torsional component, suppressed by visual fixation.
-reduction of vestibular signal in injured ear leads to relative vestibular
excitation in opposite ear = slow phase of nystagmus is toward injured ear and
fast phase is away from injured ear.
-nystagmus intensified be looking toward fast phase and decreased be looking
toward slow phase = “Alexander’s law”.
Imaging
-Get MRI to ID infarct/bleeding in pts w/ risk factors.
Special Tests
-Vestibular testing shows complete/reduced caloric response in injured ear.
-Will eventually normalize in 40% of patients.
Ddx
-Further eval only needed if concern for central because of acute vertigo does not
resolve in 48 hrs.
-Central causes for acute vertigo lasting days = stroke.
-Usually pt has other symptoms: diplopia, dysmetria, dysarthria, motor/sensory
deficits, abnormal reflexes, inability to walk w/o falling and central
nystagmus.
-Purely vertical or torsional nystagmus is highly suggestive of central
disorder.
Treatment
-Vestibular suppressant and antiemetics
-Withdraw these meds ASAP to avoid interfering w/central vestibular
compensation.
Prognosis
-Natural hx includes acute attack of vertigo lasting a few days w/ complete or partial
recovery within a few weeks/months.
-15% of pts have significant symptoms after 1 year.
-May later develop BPPV
-Vestibular rehab may help w/ residual symptoms

12/13/2013

2013-12-13T20:51:00.000-08:00

12/13/2013

Answers:

Vertigo that only lasts seconds and is accompanied by hearing loss is most likely to be?
A) Lyme Disease
B) Labyrinithitis
C) Meniere Disease
D) Perilymphatic Fistula
E) BPPV

Vertigo lasting seconds with associated hearing loss is most likely to be either a perilymphatic fistula or a cholesteatoma. BPPV also has vertigo lasting seconds, but has no associated hearing loss. Meniere disease has both but vertigo lasts hours.

What is the most common cause of peripheral vertigo?

BPPV is the most common type of peripheral vertigo. It is due to debris in posterior semicircular canal and the vertigo lasts seconds, with no hearing loss. Symptoms are associated with position.

MC Questions:
What is the primary treatment of BPPV?
A) Semicircular Canal Occlusion
B) Epley Maneuvers
C) Diuretics
D) Avoiding inciting head positions
E) Vestibular Suppressants

Free Response Question:
What are Ewald's three laws?

Quick Facts:
Meniere Disease
-Idiopathic.
-Attacks of vertigo, fluctuating hearing loss, tinnitus and aural fullness.
-Often presents in 5th decade.
Pathogenesis
-Idiopathic, possible due to impaired reabsorption of endolymphatic fluid in the
endolymphatic duct/sinuses, utricle and saccule.
-Endolymphatic sac in Meniere patients are smaller, have less absorptive tubular epithelium and have increased perisaccular fibrosis.
-Meniere patients have decreased Type II hair cells.
-Meniere patients have increased IgM complexes and C1q component, low IgA
levels.
-30% have autoantibodies to inner ear antigen.
Clinical Findings
-4 signs/symptoms:
-unilateral fluctuating SNHL
-vertigo lasting minutes-hours
-constant or intermittent tinnitus increaing in intensity before/during
vertiginous attacks.
-Aural fullness
-Pt often feels exhausted after attacks.
Diagnostic Scale of Meniere Disease:
-Certain Disease
-definitive disease + histopath confirmation
-Definitive Disease
-2+ episodes of vertigo that are 20+min
-Audiogram confirmed hearing loss
-Tinnitus and aural fullness
-Probable Disease
-One definite episode of vertigo

12/12/2013

2013-12-12T20:51:00.000-08:00

12/12/2013

Answers:

This patient presents and is found to have significant hearing loss. What is the most likely diagnosis?

A) Pendred Syndrome

B) Stickler Syndrome

C) Treacher Collins Syndrome

D) Jervell-Lange-Neilsen Syndrome

E) Waardenburg

Treacher Collins Syndrome consists of distinct craniofacial
abnormalities and hearing loss due to a malformed cochlear/vestibular
apparatus.

A 2 year old patient with SNHL presents to the ED with a syncopal episode. What diagnose should be suspected and why is it important to diagnose early?

Jervell-Lane-Nielson syndrome. This syndrome consists of SNHL w/ syncopal
attacks due to prolong QTC. Death occurs from arrythmias if not detected and treated early.

MC Questions:
Vertigo that only lasts seconds and is accompanied by hearing loss is most likely to be?
A) Lyme Disease
B) Labyrinithitis
C) Meniere Disease
D) Perilymphatic Fistula
E) BPPV

Free Response Question:
What is the most common cause of peripheral vertigo?

Quick Facts:
Benign Paroxysmal Positional Vertigo (BPPV)
-Most common types of peripheral vertigo
-Due to debris in posterior semicircular canal.
-Vertigo lasts seconds, no hearing loss, associated with position.
-Average age of 50.
-10-15% have recent hx of vestibular neuronitis and 20% have hx of recent
trauma.
Pathogenesis
-SCC has debris either in cupula or free floating in endolymph
(cupulolithiasis/canalolithiasis). The canal becomes stimulated when this
debris moves in response to gravity.
-Majority is in posterior canal but can also be in horizontal and superior.
Clinical Findings
-Sudden onset vertigo for 10-20 seconds with particular head positions.
-Rolling over in bed, getting out of bed, looking up and back (top shelf) and bending
over.
-Normal hearing, no spontaneous nystagmus, normal neuro exam.
-Only image if cannot evoke nystagmus, then get MRI to r/o other pathology
-Perform audiogram to r/o retrocochlear path.
-Perform Dix-Hallpike. There is a latency of 1-2 seconds before onset of
nystagmus/vertigo.
-Nystagmus is geotropic (down beating/rotary)
-Increases then decreases within 20 seconds
-Fatigable
-Follows Ewald law for excitation of dependence PSCC

Ewald’s three laws:
1. A stimulation of the semicircular canal causes a movement of the eyes in the
plane of the stimulated canal
2. In the horizontal semicircular canals, an ampullopetal endolymph movement cases a greater stimulation than an ampullofugal one.
3. In the vertical semicircular canals, the reverse is
true.

12/11/2013

2013-12-11T20:40:00.000-08:00

12/11/2013

Answers:

What type of hearing loss is most common in Branchio-Oto-Renal Syndrome?
A) SNHL
B) CHL
C) Mixed Hearing Loss
D) Microtia without hearing loss

Branchio-Oto-Renal Syndrome most often causes a mixed type hearing loss.

A patient is found to have bilateral acoustic neuromas. What underlying diagnosis is most likely?

Neurofibromatosis Type II

MC Questions:
This patient presents and is found to have significant hearing loss. What is the most likely diagnosis?
A) Pendred Syndrome
B) Stickler Syndrome
C) Treacher Collins Syndrome
D) Jervell-Lange-Neilsen Syndrome
E) Waardenburg

Free Response Question:
A 2 year old patient with SNHL presents to the ED with a syncopal episode. What diagnose should be suspected and why is it important to diagnose early?

Quick Facts:
Steps in Vestibular Eval
1. H&N exam, include CNs
2. Spontaneous/gaze-evoked nystagmus w/ Frenzel glasses
3. Smooth Pursuit - “follow my fingers”
4. Saccades - “look to my left/right finger when I say to”
5. Head thrust
6. Headshake = “10 degrees, 2 cycles, 20 seconds”
7. Dynamic visual activity - “look at schnell chart w/ head shake”
8. Fixation suppression - “look at your thumb during rotation”
9. Positional testing - Dix-Hallpike
10. Cerebellum - finger to nose, rapid alternating movements, heel to
shin
11. Posture -Romberg

12/10/2013

2013-12-10T21:07:00.000-08:00

12/10/2013

Answers:

A 10 year old boy is found to have severe bilateral hearing loss and a large goiter. What is the most likely diagnosis?
A) MENIIB
B) Neurofibromatosis Type I
C) Neurofibromatosis Type II
D) Pendred Syndrome
E) Waardenburg Syndrome
D) Treacher Collins Syndrome

Pendred syndrome is the most common syndromic form of deafness (10%). It includes SNHL + goiter, often before puberty. Hearing loss is congenital, bilateral, mod-profound and sloping in higher frequencies. Pts often have enlarged vestibular aqueduct and mondini-type malformations.

What factors help categorize the four categories of Waardenburg Syndrome?

Dystopia canthorum, upper limb abnormalities and Hirschsprung disease.

Waardenburg syndrome patients also have pigmentary abnormalities and SNHL. The four subtypes are:
-Type I = + dystopia canthorum, PAX3
-Type II = no dystopia canthorum, MITF, SNA12
-Type III = + dystopia canthorum, + upper limb abnormalities, PAX3
-Type IV = - dystopia canthorum, + Hirschsprung disease, EDNRB, EDN3,
SOX10

MC Questions:
What type of hearing loss is most common in Branchio-Oto-Renal Syndrome?
A) SNHL
B) CHL
C) Mixed Hearing Loss
D) Microtia without hearing loss

Free Response Question:
A patient is found to have bilateral acoustic neuromas. What underlying diagnosis is most likely?

Quick Facts:
Jervell-Lange-Nielsen = SNHL w/ syncopal attacks due to prolong QTC.
-Death occurs if not treated.

Treacher Collins =Distinct craniofacial abnormalities.
-Hearing loss due to malformed cochlear/vestibular apparatus.

Stickler Syndrome = eye symptoms include myopia, astigmatisms and cataracts, arthropathy, cleft palate and SNHL.