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Flashcards in Otology Deck (181):

What are the five primary causes of conductive hearing loss after stapedectomy?

  • Failure to recognize obliterative otosclerosis of the round window
  • Displacement of the prosthesis after head trauma or large changes in middle ear pressure
  • Necrosis of the long process of the incus
  • Migration of the prosthesis in the oval window
  • Adhesions


When is stapedectomy contraindicated?

  • In young children until it has been demonstrated that they are not prone to otitis media
  • In the presence of active middle or external ear disease
  • Active URI
  • tympanic membrane perforation
  • Meniere's disease.


What psychological problems are contraindications to cochlear implantation?

  • Organic brain dysfunction
  • mental retardation
  • psychosis
  • unrealistic expectations.


What is the incidence of malleus ankylosis during primary surgery for otosclerosis?



What are the expected residual hearing levels after PORP and TORP?

15 dB conductive hearing loss PORP; 25 dB conductive hearing loss TORP.


What is the incidence of ossification after pneumococcal meningitis?



What percent of patients will have improved tinnitus and hearing after endolymphatic sac surgery?

50% experience improvement in tinnitus and 30-40% experience improvement in hearing.


What percent of patients will have new bone growth covering the round window niche and membrane during cochlear implantation?



What is the incidence of malleus ankylosis during revision surgery for otosclerosis?



What percent of patients have improvement of vertigo after endolymphatic sac surgery?

70% experience complete relief, 20% experience decreased vertigo.


Why is stapedectomy dangerous in patients with Meniere's disease?

A dilated saccule may sit immediately beneath the footplate and be injured upon entry into the vestibule.


How do the surgical findings differ during removal of a congenital cholesteatoma from removal of a cholesteatoma associated with chronic suppurative otitis media?

Absence of inflammatory changes/adhesions and easier removal with potential for complete preservation of the middle ear mucosa.


What are the indications for using plastic sheeting in middle ear surgery?

Absence of mucosa on the promontory, in most of the middle ear, or in the middle ear cleft (except in the eustachian tube).


What are the indications for simple mastoidectomy?

Acute coalescent mastoiditis with complications or acute mastoiditis that does not resolve after appropriate antibiotic therapy and myringotomy.


How should an extruded prosthesis be managed?

Allow spontaneous extrusion; TM may heal and make a spontaneous connection.


What are the complications of lateral tympanoplasty?

Anterior blunting, lateralization, epithelial pearls, and canal stenosis.


What are the indications for performing a lateral tympanoplasty?

Anterior or large perforations, revision tympanoplasty, or if the anterior canal wall is in the way.


Where is the endolymphatic sac?

Anterior to Trautmann's triangle within the dura, medial and inferior to the posterior sec.


Which way is the sigmoid sinus retracted in the retrosigmoid approach to vestibular nerve section?



What is the management of injury to the sigmoid sinus during mastoidectomy?

Apply gentle pressure, place a Surgicel or Gelfoam patch, and continue with surgery.


What are the two most important landmarks in the middle fossa approach to the internal auditory canal?

Arcuate eminence and hiatus for the greater superficial petrosal nerve.


What are the options for surgical management of the chronically draining mastoid cavity?

Autologous cultured epithelial graft (from buccal mucosa), large meatoplasty, revision mastoidectomy, reconstruction of canal wall with an aerated cavity, mastoid cavity obliteration, and mastoid/middle ear obliteration.


Which of these is superior in complete elimination of vertigo?

Both are equally effective.


Which laser can be used on the tympanic membrane to treat atelectasis?

Carbon dioxide laser.


Where is the safest place to create an opening in the stapes footplate?

Central area.


What are the boundaries of the facial recess?

Chorda tympani laterally, upper mastoid segment of VII medially, and bone of fossa incudis superiorly.


A 45-year-old man is being evaluated for cochlear implantation. He has a long history of chronic ear disease that is now dormant and has a modified radical mastoid cavity. What other procedures may be considered in conjunction with cochlear implantation?

Close the external auditory canal and obliterate the mastoid and middle ear.


What are the surgical landmarks for the tympanic segntent ofVII?

Cochleariform process, oval window, pyramidal process, semicanal for the tensor tympani, vertical groove on promontory for the tympanic nerve.


What is the best surgical approach for facial nerve exploration in a patient with a temporal bone fracture distal to the geniculate ganglion with intact hearing?

Combined transmastoid/middle fossa approach.


What approach is most often used for longitudinal fractures?

Combined transmastoid/middle fossa.


What are some clinical clues to an aberrant facial nerve?

Congenitally malformed auricle, ossicular abnormalities, craniofacial anomalies, and conductive hearing loss.


Should a cholesteatoma be removed over a fistula?

Controversial, in that leaving a piece of matrix to seal the fistula increases the risk of recurrent cholesteatoma, while completely removing the matrix and exposing the fistula increases the risk of hearing loss and vertigo.


What is a modified radical mastoidectomy?

Conversion of the mastoid, epitympanum, and external auditory canal into a common cavity by removal of the posterior and superior external bony canal walls.


What is a radical mastoidectomy?

Conversion of the mastoid, antrum, and middle ear into a common cavity, with removal of the tympanic membrane, malleus, incus, chorda tympani, and mucoperiosteum.


Which complication is more likely in patients with cochlear dysplasia who undergo cochlear implantation?

CSF leak.


What is the primary disadvantage of the translabyrinthine approach?

Destroys hearing permanently.


What increases the likelihood of headaches after the retrosigmoid approach?

Drilling out of the medial portion of the lAC.


What are the surgical options for treatment of Meniere's?

Endolymphatic shunt, destructive labyrinthectomy, and vestibular nerve section.


Which of these is the only surgical procedure considered in an only-hearing ear?

Endolymphatic shunt.


Which of these is most commonly performed?

Endolymphatic shunt.


A patient with Meniere's disease and profound SNHL is being evaluated for cochlear implantation. She still has infrequent episodes of vertigo. What test should be ordered prior to surgery?



What are the signs and symptoms of a pos1stapedectomy perilymph fistula?

Episodic vertigo, especially with exertion, SNHL, loss of speech discrimination, and nystagmus with changes of air pressure on the TM.


What factors contribute to extrusion of middle ear prostheses?

Eustachian tube dysfunction (70%), graft failure, and cartilage resorption.


What are the advantages of lateral tympanoplasty?

Excellent exposure, high graft take rate (95%), and most versatile approach.


What are the indications for staging a tympanoplasty without mastoidectomy?

Extensive mucous membrane destruction, stapes fixation.


What structures are resected in a subtotal temporal bone resection?

External auditory canal, middle ear, petrous bone, TMJ, and parotid gland with facial nerve.


True/False: Presence of PETs is a contraindication to cochlear implantation.



True/False: Surgery is contraindicated in children with unilateral atresi•a.

False: Many will operate if the patient is likely to achieve a residual conductive deficit of 30 dB or less.


What are the most common complications of cochlear implantation?

Flap complications, electrode dislocation or malinsertion, facial nerve injury, and stimulation of facial nerve postoperatively.


When is surgical exploration indicated after temporal bone fracture?

For massively displaced fractures with compromise of the carotid artery or VII; or for VIIth nerve paralysis with >90% degeneration documented on electroneurography (ENoG) within 14 days of the injury.


What is the success rate of vestibular nerve section?

For the middle fossa approach, complete elimination of vertigo is achieved in >8o%; for the posterior approaches, complete elimination of vertigo is achieved in >70%.


What is the prognosis after such an injury?

Good if immediately recognized and treated.


What are the landmarks for identification of the lAC during middle fossa approach to vestibular nerve section?

Greater superficial petrosal nerve, malleus head, and superior SCC.


How is the facial nerve identified using the tympanic nerve?

Groove for the tympanic nerve is followed superiorly to the cochleariform process.


What are the disadvantages of the canal-wall-down procedure in the management of cholesteatoma?

Healing is slower, indefinite periodic cleaning and dry ear precautions are required, and hearing aids are more difficult to fit in the meatus.


What are the advantages of using porous polyethylene prostheses over fitted autograft ossicles?

Hearing is more stable, decreased incidence of residual and recurrent cholesteatoma.


Following acoustic neuroma resection, what problem do patients perceive as most troublesome?

Hearing loss.


What is the significance of a white versus a blue floating footplate?

Hearing success is much less in the presence of a white floating footplate (52%) versus a blue floating footplate (97%).


What are the most common injuries encountered on surgical exploration?

Hematoma and contusion with bony spicules impinging on the nerve sheath.


What can cause persistent cavity discharge after CWD procedures?

High facial ridge, particularly large cavity, open middle ear space, inadequate meatal opening, poor postoperative care leading to infection.


What condition increases the likelihood of this happening?

History of meningitis.


What if the nerve is only partially transected?

If greater than 1/2 remains, reapproximate the remaining nerve and perform regional decompression. If less than 1/2 remains, remove the injured segment and repair as with complete transection.


What is the significance of SNHL after stapedectomy?

If no tissue graft was used, 50% of SNHL will be due to fistulas and should be revised.


Revision stapedectomy is performed. What should be done with the original prosthesis?

If possible, it should be left in place, and a second fenestra and prosthesis should be placed.


What is Donaldson's line?

Imaginary line in the plane of the horizontal SCC back to the sigmoid sinus marking the top of the endolymphatic sac.


What is the management of intraoperative violation of the labyrinth?

Immediate application of a Gelfoam patch or other tissue seal (other than fat).


What is the management of intraoperative facial nerve transection?

Immediate repair with primary anastomosis if possible.


When is mastoid and middle ear obliteration most appropriate?

In a dead ear, without cholesteatoma.


How is electrocochleography helpful prior to destructive surgery for Meniere's disease?

In patients with unilateral disease, abnormalities in the asymptomatic ear (SP:AP >35%, distorted CM with after-ringing) predict development of hydrops in that ear.


What are the reasons for persistent conductive hearing loss after aural atresia repair?

Inadequate mobilization of the ossicular mass from the atretic bone, an unrecognized incudostapedial joint discontinuity, or a fixed stapes.


What are the indications for surgical treatment of BPPV?

Incapacitating symptoms >1 year, confirmation of BPPV with Dix-Hallpike on at least three visits, failure of conservative treatment, normal head MRI.


Which portions of the ossicular chain are always removed in canal-wall-down procedures?

Incus and head of the malleus.


Which areas of the middle ear are most difficult to see during mastoidectomy?

Infrapyramidal and tympanic recesses.


Into which ear is the implant placed if there is no difference acoustically between ears?

Into the better surgical ear as determined by CT scan (side with the least amount of ossification or fibrosis within the scala tympani).


Into which ear is the implant placed if the patient has had different durations of hearing impairment in each ear?

Into the ear that has had the shortest duration of deafness.


What is the most important question to answer in the preoperative evaluation of a temporal bone tumor?

Is the carotid artery or brain involved?


During stapedectomy, the entire stapes footplate falls into the vestibule. What should be done?

It should be left in the vestibule, as attempts to retrieve it are more likely to cause damage than leaving the footplate where it is.


A patient develops a CSF leak after resection of an acoustic neuroma. A pressure dressing and lumbar drain are placed with no improvement. Wound exploration and reclosure are performed, and the leak recurs. What is the next step?

It the tympanic membrane is intact and hearing is present, plug the eustachian tube via a middle fossa approach. If the tympanic membrane is not intact and hearing is not present, perform a blind sac closure of the external auditory canal and obliterate the middle ear and eustachian tube.


What is the best method of excising a glomus tympanicum tumor?



What portion of the Vlllth nerve is sectioned in vestibular nerve section?

Lateral portion (superior and inferior vestibular nerves) in the lAC.


What are the surgical landmarks for VII in its mastoid segntent?

Lateral SCC, fossa incudis, and the digastric ridge.


What is the most common location for iatrogenic labyrinthine fistula formation during mastoidectomy?

Lateral SCC.


What are the landmarks of the tympanic segntent of VII from the mastoid approach?

Lateral semicircular canal (SCC) and the cog.


What are the disadvantages of the canal wall up (CWU) approach?

Limited exposure of the anterior epitympanum, sinus tympani, and facial recess.


What are the disadvantages of lateral tympanoplasty?

Longer healing time, potential for anterior blunting or lateral healing, and technically more difficult.


What are the two most important principles of CWD procedures?

Lowering the posterior canal wall to create a round cavity and creating a large meatus.


What is the single most important factor affecting hearing results after CWD tympanomastoid surgery?

Maintenance of a pneumatized space juxtaposed to the round window.


What is obliterative otosclerosis?

Margins of the footplate cannot be seen or removed.


What is the relationship ofVII to the lateral SCC and the fossa incudis?

Medial to the fossa incudis and inferior to the lateral canal.


What two inner ear malformations are contraindications to cochlear implantation?

Michel deformity and small lAC syndrome (


What are the four primary approaches to vestibular nerve section?

Middle fossa, retrosigmoid, transcochlear, and retrolabyrinthine.


Which approach is best in patients with tumors

Middle fossa.


Which of these is associated with the greatest risk of damage to VII?

Middle fossa.


If the canal wall up (CWU) procedure is chosen, what are the indications for a second look?

Missing middle ear mucosa or extensive cholesteatoma.


What congenital ear malformation is most commonly associated with perilymph fistula in children?

Mondini deformity.


What are the potential problems with a type IV tympanoplasty?

Narrowing of the middle ear space and graft lateralization.


Where is the facial nerve most commonly injured during mastoid surgery?

Near the second genu as it enters the mastoid cavity.


What procedures are often performed in conjunction with a lateral temporal bone resection?

Neck dissection, parotidectomy, and, occasionally, partial mandibulectomy.


What other procedures are routinely performed with a subtotal temporal bone resection?

Neck dissection, temporal craniotomy to rule out transdural extension.


What nerve is involved in paroxysmal lacrimation?

Nervus intermedius.


What are the indications for surgical exploration of the facial nerve following temporal bone trauma?

NET >3.5 rnA side-to-side threshold differences or ENoG >go% degeneration.


How is the STAMP procedure different from traditional laser stapedotomy?

No prosthesis is used; the anterior crus and anterior 1/3 of the footplate are vaporized using a hand-held argon laser.


What are the indications for second look surgery after removal of a congenital cholesteatoma?

Obvious recurrent disease, unexplained deterioration in hearing, and concern about the adequacy of the initial surgery or disease found to extend into the antrum or mastoid.


What type of cholesteatoma is most frequently found in the facial recess?

One associated with a perforation below the posterior malleolar fold.


A patient who recently had a cochlear implant placed complains of throat pain every time someone talks to him. What has happened?

One of the electrodes of the cochlear implant is stimulating Jacobson's nerve on the promontory.


What advantage does hugging the middle fossa dura have on protecting the facial nerve?

One will enter the middle ear first in the epitympanum; the facial nerve will always lie medial to the ossicular heads in the epitympanum.


What are the contraindications to vestibular nerve section?

Only hearing ear, signs of central vestibular dysfunction, and poor medical health.


Is the facial nerve sacrificed during lateral temporal bone resection?

Only if it is involved with tumor.


According to Sheehy, in which situations is the canal wall down (CWD) approach most appropriate?

Only-hearing ear, very contracted mastoid, mastoid with a labyrinthine fistula, or presence of canal wall erosion due to disease.


What is the most common cause of perilymph fistula?

Otologic surgery (stapedectomy).


The STAMP procedure is advantageous for which type of otosclerosis?

Otosclerosis confined to the fissula ante fenestram.


What is the prognostic significance of a normal AP-SP prior to surgery?

Outcomes are significantly better.


Which patients are at greater risk for a "perilymph gusher"?

Patients with congenital stapes fixation and a patent cochlear aqueduct or a large vestibular aqueduct.


In terms of functional level, which patients with Meniere's disease are candidates for chemical or surgical labyrinthectomy?

Patients with functional levels of 4, 5, or 6.


What is the most common and most difficult to manage problem after any vestibular destructive surgery?

Persistent disequilibrium (20%).


What is the most common postoperative complication of pressure equalizing tube insertion?

Persistent otorrhea.


What vessels can be injured in the middle ear during tympanoplasty?

Persistent stapedial artery, superficial petrosal branch of the middle meningeal artery, high-riding jugular vein, and anomalous carotid artery.


What are the most common reasons for mastoid surgery failure without recurrent cholesteatoma?

Persistent suppurative disease in unexenterated air cells (most commonly at the sinodural angle and along the tegmen) and technical factors such as high facial ridge or meatal stenosis.


What technique is employed during ossiculoplasty to decrease the risk of prosthesis extrusion?

Placement of cartilage between the prosthesis and the tympanic membrane.


What techniques can be used to accomplish this?

Placement of the fascia graft such that it does not obliterate the space between the eustachian tube orifice and the round window; placement of silastic crescent in the hypotympanum.


Unbeknownst to the surgeon, the dura is torn during mastoidectomy, and postoperatively, the patient develops a severe headache, followed by hemiplegia and coma. What has likely happened?

Pneumocephalus; torn dura can create a ball valve-like effect and trap air from the middle ear. Influx of air may occur during Valsalva or as a result of high intracranial negative pressure due to the rapid escape of CSF through the tear.


What factors are considered contrindications to correction of unilateral atresia?

Poor mastoid pneumatization, anterior displacement of the middle ear, and facial nerve anomalies


In patients with bilateral otosclerosis, which ear should be operated on first?

Poorer hearing ear.


Which way is the sigmoid sinus retracted in the retrolabyrinthine approach to vestibular nerve section?



What is the most important factor in assessing the possibility of surgery in a patient with congenital aural atresia?

Presence of the stapes.


What is the most common complication of stapedectomy?

Prosthesis displacement.


What is a "perilymph gusher"?

Rapid release of perilymph after stapes footplate fenestration due to pressure and fluid from the CSF compartment venting through the inner ear.


What are the most common reasons for recurrent conductive hearing loss after tympanoplasty?

Recurrent perforation, blunting of the angle between the tympanic membrane and the external auditory canal, graft lateralization, graft thickening and adhesions, and severe graft atelectasis.


What is the benefit of amputating the mastoid tip?

Reduces cavity size and eliminates a dependent cavity area that is not visible.


What is the management of a "perilymph gusher"?

Reduction of CSF pressure with mannitol and/ or a lumbar drain; application of a tissue seal over the oval window fistula using fascia, perichondrium, or fat and secured with a stapes prosthesis; and postoperative hospitalization with continued reduction in CSF pressure.


What are the reasons for recurrent conductive hearing loss after aural atresia repair?

Refixation of the ossicular chain or tympanic membrane lateralization.


Why is posterior sec ablation most often the procedure of choice?

Relatively easier, less risk to hearing, and excellent long-term results (approaches 100%).


How can this be treated?

Removal of the electrode(s) stimulating the nerve (probably 17 or 18).


What is the management of injury to the dura with CSF leak during mastoidectomy?

Repair with temporalis fascia held in place with sutures or packing and continue with surgery; small tears can be managed with a Surgicel or Gelfoam patch.


Which of these approaches is at higher risk for a CSF leak?



Which approach is best in patients with tumors > 2.5 em with good hearing?



Which of these is most likely to result in postoperative headaches?



In patients with bilateral otosclerosis and equal hearing loss, which ear should be operated on?

Right-handed surgeon should work on the left ear (or patient preference).


Using the rating system developed by Jahrsdoerfer, what score is associated with the best outcome after surgical treatment of aural atresia?

S or greater (So% chance of obtaining an SRT 15-25 dB).


What are the most common complications of acoustic neuroma resection?

Sensorineural hearing loss, paralysis of VII, cerebrospinal fluid leak (10-35%), meningitis (1-10%), and intracranial hemorrhage (0.5-2%).


What is the most common cause of failure using a fitted ossicle for middle ear reconstruction?

Separation of the ossicle from the stapes.


What other techniques can help improve hearing results?

Shielding the round window to increase the difference in sound pressure between the oval and round windows; placing the graft directly atop the head of the stapes when the suprastructure is present; using a TORP or placing the graft directly on the stapes footplate when the suprastructure is not present (type IV tympanoplasty).


What is the relation of the lateral SCC to the fossa incudis?

Short crus of the incus is inferolateral to the lateral SCC; the fossa incudis is at the tip of the short crus.


What factors are associated with improved outcome after cochlear implantation?

Shorter duration of auditory deprivation; postlingual onset of deafness; etiology of deafness (meningitis patients have poorer outcomes); higher IQ; better preoperative word and sentence recognition; lip reading ability; better preoperative residual hearing; optimized implant technology and processing; an intact, nonossified cochlea; and in kids, younger age at the time of implantation, motivated family, oral preoperative education, and oral education rehabilitation.


What are the surgical options for treatment of BPPV?

Singular neurectomy, posterior SCC ablation.


If a canal-wall-down procedure is used to treat a posterior or superior retraction cholesteatoma, what would be the most likely site of residual cholesteatoma?

Sinus tympani.


What factor is most related to hearing outcome after surgery?

Size of tumor; significantly more likely to have preservation of hearing if


What surgical approach is used for small, localized tumors of the cartilaginous ear canal that have not invaded deep structures?

Sleeve resection.


What are the indications for using a TORP when the stapes suprastructure is present?

Stapes tilted toward the promontory, partial arch necrosis, and unusually deep oval window niche where a PORP might contact the fallopian canal and/or promontory.


What surgical approach is used for tumors involving the middle ear that appear confined to the temporal bone?

Subtotal temporal bone resection.


What is the significance of Tullio's phenomenon after stapedectomy?

Suggests that the prosthesis is too long and impinging on the saccule.


Which approach is best in patients with normal hearing?

Supralabyrinthine approach.


Ten days after stapedectomy, your patient complains of progressive hearing loss and vertigo that does not respond to steroids. What do you do?

Take the patient back to the operating room to explore for a granuloma. If one is found, remove the granuloma and place a new prosthesis with a tissue seal over the oval window.


Of the disorders of lacrimation, taste, and salivation, which is the first to return after injury to the nervus intermedius?



What are the disadvantages of singular neurectomy?

Technically difficult, 10% risk of SNHL, and nerve may be inaccessible under the basal turn of the cochlea in a small number of patients.


What is the Paiva flap?

Technique used for mastoid obliteration where the soft tissue off the back of the ear is swung into the mastoid.


During stapedectomy, how is the round window evaluated for normal movement?

The membrane is not readily visible, so a drop of saline is placed in the niche and movement is seen as a change in light reflection on the meniscus when the prosthesis is palpated.


What are the two most important landmarks of the anterior approach?

The middle cranial fossa dura superiorly and the TMJ anteriorly.


Why is it important to saucerize the cavity margins?

The soft tissues and auricle will assume a more medial position during healing, resulting in a smaller cavity.


In patients where one ear has previously been operated on and hearing loss is equal bilaterally, which ear should be operated on?

The unoperated ear.


Why should visible lasers not be used for revision stapedectomies?

These lasers depend on pigment for absorption so when working around white bones and tendons, inner ear damage is more likely.


Why should surgery be delayed until age 5?

To allow for completion of pneumatization of the temporal bone.


What is the purpose of the plastic sheeting in these conditions?

To prevent adhesions from forming and to allow mucosa to grow over denuded areas.


What operation is performed for tumors that involve the medial aspect of the temporal bone in the region of the petrous apex?

Total temporal bone resection.


What are the three surgical approaches to resection of an acoustic neuroma?

Translabyrinthine, middle fossa, and retrosigmoid.


Which approach offers the best exposure?



Which approach results in the best facial nerve outcome?



Which approach is best in the high-risk surgical patient, regardless of tumor size?



What are the two basic approaches for repair of aural atresia?

Transmastoid and anterior approaches.


What are the two approaches to labyrinthectomy?

Transmastoid and transcanal.


True/False: Results of cochlear implantation in children with congenital inner ear malformations are comparable with those without malformations.

True (if the cochlea is fully intact).


True/False: After subtotal temporal bone resection, all patients will have facial nerve paralysis and a dead ear.



True/False: A patient with a score of 5 or less is considered a very poor operative candidate.



True/False: The modified radical mastoidectomy does not involve a tympanoplasty.



True/False:The electrode of the cochlear implant is normally placed into the scala tympani.



Where do most facial nerve injuries occur during middle ear surgery?

Tympanic segment.


Which complication is more likely in patients with a history of otosclerosis who undergo cochlear implantation?

Unwanted facial nerve stimulation due to demineralization of surrounding bone.


What if primary anastomosis is not possible?

Use a cable graft with great auricular nerve as the donor.


What is Tullio's phenomenon?

Vertigo with loud noise.


When is surgical exploration indicated for facial nerve paralysis after gunshot injuries?

When >8o% degeneration is documented on ENoG within 14 days of the injury.


What surgical approach is used for tumors that involve both the cartilaginous and bony ear canal without extension into the middle ear?

Lateral temporal bone resection.