OTOLOGY-NEUROTOLOGY UPDATE
Selections from UCSF Otolaryngology Update: 2007, presented by University of California, San Francisco, School of
Medicine
| CHOLESTEATOMAS: CANAL-WALL UP VS CANAL-WALL DOWN —Anil K. Lalwani, MD, Mendik Foundation Professor
and Chair, Department of Otolaryngology–Head and Neck Surgery, Professor of Pediatrics, and Professor of Physiology
and Neuroscience, New York University School of Medicine, New York, NY
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| Etiology: congenital—epidermoid formation persists through embryogenesis; white mass present at birth; tympanic
membrane intact; no history of aural infection or surgical procedure; acquired—primary and secondary; etiologies include
immigration and invasion (cholesteatoma arises in retraction pocket), trauma, and metaplasia (result of longstanding
infection); epitympanic cholesteatomas grow lateral to incus; mesotympanic cholesteatomas grow underneath incus
(significant destruction of stapes superstructure); atticotomy often appropriate for epitympanic cholesteatomas (may
erode incus and head of malleus but usually do not affect stapes), but insufficient for mesotympanic cholesteatomas
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| Presentation: otorrhea (with acquired cholesteatoma) or hearing loss (congenital cholesteatoma impinges on ossicular
chain); white mass behind tympanic membrane (congenital) or retraction pocket of granulation tissue (acquired); hearing
loss—usually conductive, but may have element of sensorineural hearing loss (SNHL; important to identify before surgery)
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| Evaluation: imaging—computed tomography (CT) of temporal bone aids surgical planning by providing information
about involvement of ossicular chain, mastoid, facial nerve, and tegmen, and identifying presence of lateral canal fistula; assessing
need for surgery—if retraction pocket can be cleaned in office, surgery not warranted; retraction pockets with retained
keratin or recurrent granulation tissue and otorrhea require surgery
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| Surgical options: transcanal approach—for congenital cholesteatomas; if dissection requires significant manipulation
of malleus, disarticulate incudostapedial (IS) joint to prevent SNHL caused by damage to stapes; note—biopsy not necessary
in patients with white mass behind eardrum; requires excision of eardrum (unnecessarily invasive procedure); canal-wall
up approach—for acquired cholesteatomas; indicated for patients with extensive pneumatization of mastoid;
advantages include ease of maintenance and preservation of hearing; published meta-analyses show no significant difference
in rate of recurrence, compared to canal-wall down procedure (contrary to popular belief); canal-wall down
approach—indications include contracted mastoid and poor visualization; unreliable patient sometimes considered indication
(because surgery not staged), but approach requires more maintenance and follow-up (eg, patient must return every
6 mo for cleaning); presence of semicircular canal fistula or preserved hearing may warrant canal-wall down
approach; in patients with significant hearing loss, consider leaving canal-wall up, removing matrix, and plugging canal
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| Canal-wall up technique: make incision (postauricular [used by speaker] or endaural); perform mastoidectomy; open
capsule and debulk center; dissect matrix from tegmen (superiorly and posteriorly), being careful not to tear matrix or to
leave tissue behind; open epitympanum to area of incus, and make transcanal incision with needlepoint Bovie; separate intact
IS joint (using laser or right-angle hook); remove incus and head of malleus; perform facial recess in all patients with
acquired cholesteatomas; use Rosen needle or joint knife to peel off matrix (if present) from stapes; use laser to remove
stapes superstructure; dissect remainder of capsule; reconstruction—prosthesis determined by surgeon preference, but,
occasionally, hearing may be sufficient without prosthesis (perform hearing test first); reconstructing attic during tympanoplasty
reduces risk for retraction of eardrum and recurrence of cholesteatoma
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| Notes on canal-wall down technique: remove bone to anterior external auditory canal to access and clean bowl; perform
large meatoplasty to facilitate cleaning of mastoid cavity
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| Surgical pearls: use of laser (potassium titanyl phosphate [KTP] or argon) reduces bleeding (especially useful along ossicular
chain); always monitor facial nerve; always stage (except in canal-wall down); follow up at 4 mo to catch recurrence
at early stage
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| Recurrences: most common in oval window and sinus tympani; risk factors—young age; ossicular erosion; disease in
sinus tympani (removing medial external auditory canal improves exposure in canal-wall up approach)
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| MIDDLE EAR PHARMACOTHERAPY —Lawrence R. Lustig, MD, Associate Professor, Department of Otolaryngology–
Head and Neck Surgery, and Director, Division of Otology, Neurotology, and Skull Base Surgery, University of California,
San Francisco School of Medicine
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| Rationale: intratympanic (transtympanic) delivery of medication results in high concentration at target site without systemic
effects; endolymph concentration of corticosteroids almost 4 times higher when delivered by intratympanic injection
than by intravenous (IV) or oral routes
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| Methods: medication delivered to inner ear through round window, from there into scala tympani, and ultimately to organ
of Corti or stria vascularis; intratympanic injection—fast, simple in-office procedure delivers ≈0.5 mL of fluid; making
second hole in eardrum (ie, “blow hole”) before delivering medication prevents fluid from squirting out during removal
of syringe; microwick technique—small wick placed through tympanostomy tube to round window niche; patient adds
ear drops at home (delivered to inner ear via wick); comparison of approaches—single intratympanic injection of gentamicin
resulted in high concentration, which quickly dissipated; microcatheterization (earlier form of microwick technique)
resulted in more sustained release
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| Applications: SNHL—intratympanic injections of steroids used as primary and salvage treatments for patients with idiopathic
sudden SNHL (controlled study comparing effects of intratympanic and oral steroids in progress); treatment
window lasts 4 to 6 wk after onset of SNHL; currently, speaker offers combination therapy with intratympanic injections
and oral steroids; Meniere’s disease—anecdotal evidence that intratympanic steroids help control breakthrough vertigo
and may prevent need for destructive procedures; intratympanic gentamicin also used in Meniere’s disease (results in
chemical labyrinthectomy; not recommended as primary therapy); risk for bilateral disease should be considered before
use; noise-induced hearing loss—oral N-acetylcysteine taken 2 days before noise exposure (and continuing through 2
days after exposure) attenuates hearing loss; intratympanic administration currently being studied; other antioxidants (eg,
glutathione, vitamin E) and intratympanic steroids also shown to attenuate noise-induced hearing loss in laboratory studies;
ototoxicity—intravenous L-methionine prevents ototoxicity caused by cisplatin; laboratory studies show intratympanic
injection of D-methionine also beneficial
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| Emerging technologies: drug delivery—reaching apex of cochlea problematic; new technologies (eg, modified cochlear
implant electrodes with drug delivery ports) address this; attaching osmotic infusion pump allows for continuous
delivery; improving outcomes of cochlear implantation—brain-derived neurotrophic factor (BDNF) helps preserve neurons
of spiral ganglion; gene therapy—small interfering RNA technology has many potential applications (eg, regrowth
of hair cells, as seen in animal models); hybrid devices—cochlear implants merging with hearing aids or middle ear implants;
drug-eluting devices
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| IMPLANTABLE MIDDLE EAR HEARING AIDS: NOT DEAD YET —Dr. Lustig
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| Conventional hearing aids: advantages—noninvasive; removable; programmable; technology constantly improving
and simple to upgrade; binaural hearing achieved when used in both ears; disadvantages—cost; distortion (especially in
patients with severe hearing loss); difficulty distinguishing voices in crowd; feedback; esthetics; social stigma; occlusion;
risk for recurrent otitis externa; maintenance, including ongoing costs; underlying medical conditions may preclude use
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| Implantable middle ear hearing aids: general structure—microphone; signal processor; transducer (piezoelectric
or electromechanical), coupled to ossicular chain (incus or stapes); Envoy—eardrum and malleus act as microphone; incus
removed, and sensor attached to head of malleus; processor articulates with stapes; no external parts; Middle Ear
Transducer—most powerful of these devices; earlier device had external processor (current version fully implantable,
with microphone beneath skin); couples directly to incus; SoundTech—device, similar to in-canal hearing aid, drives
magnet coupled to IS joint; Vibrant Soundbridge—floating transducer vibrates in response to sound; attaches to incus
and IS joint; although excellent gains (particularly in lower frequencies), manufacturer (Symphonix) stopped production,
based on lack of economic viability; status—several devices, including SoundTech, no longer produced; Middle Ear
Transducer in clinical trials in United States; Envoy developing fully implantable system; Soundbridge bought by Med-
El
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| Summary: advantages—well tolerated; greater gain than conventional hearing aids; no occlusion or feedback; better
perceived sound quality; disadvantages—cost; some devices require disruption of ossicular chain; uncertain future; new
applications—congenital aural atresia (achieve near closure of air–bone gap); hybrid technology—combination with
cochlear implants for patients with partial hearing loss
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| Hybrid Cochlear Implants —Dr. Lustig
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| Background: candidates—patients with preserved low-frequency hearing but absent high-frequency hearing; patients
ineligible for cochlear implants (eg, sentence scores too high), but who have poor results with hearing aids; aided consonant-nucleus-consonant
(CNC) word scores \>10% but <60% in implanted ear and <80% in contralateral ear; mode of
action—standard or modified cochlear implant partially inserted into cochlea preserves underlying hearing and electrically
stimulates high-frequency neurons; hearing aid enhances low-frequency hearing; early studies—implant improved
understanding of speech in quiet and noise
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| Implant: similar to Nucleus Freedom cochlear implant; electrode array smaller than standard and has 6 half-banded electrodes
(instead of standard 24)
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| Notes on surgical technique: drill down to endostium of scala tympani in front of round window; place stimulator;
use pick to sharply enter cochlea, anterior and inferior to round window membrane; insert implant partway into cochlea
(reaches one-quarter to halfway into basal turn); position electrode array in scala tympani; seal cochleostomy using fascial
cuff; after surgery—fit contralateral ear with behind-the-ear processor; fit implanted ear with in-canal hearing aid
(same processor drives hearing aid and implant)
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| Results: study enrolled 87 patients; at analysis, 60 patients at 12-mo follow-up; preservation of hearing—at activation,
hearing maintained within 30 dB of preoperative hearing, but decreased over time; CNC word scores improved 20% (implant
compared to hearing aid) and 26% (hybrid mode compared to bilateral hearing aids); Bamford-Kowal-Bench
speech-in-noise (BKB-SIN) test improved by 5.4 dB (corresponds to 40%-50% improvement in sentence-recognition
scores); significantly improved recognition of familiar melodies (ie, music appreciation), largely due to preservation of
low-frequency hearing; note—not all patients have improvement in CNC word score or BKB-SIN test, but 70% of patients
show improvement in at least one measure
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| Summary: initial results show electric-acoustic stimulation to be superior to acoustic or electric stimulation alone; best results
associated with simultaneous use of implant and hearing aid; benefits seen for speech (especially in noise) and music
perception
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| Emerging technologies: hybrid device with 10 electrodes; thinner arrays will allow insertion directly through round
window (avoiding cochleostomy)
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| COUNSELING PATIENTS ABOUT TINNITUS —Robert W. Sweetow, PhD, Professor of Otolaryngology and Director
of Audiology, University of California, San Francisco, School of Medicine
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| Providing hope: ≈80% of patients with tinnitus benefit from treatment; telling patients “there is nothing we can do” sets
up counterproductive cognitive association
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| Define scope of problem: when asked about percentage of time tinnitus bothersome, most patients respond “100%”;
good opportunity for education and reframing; important to ask how tinnitus affects patient’s behaviors, determine patient’s
attitudes about tinnitus, and identify factors that influence tinnitus
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| Etiology: other medical problems must be ruled out before referring patient to audiology; initial triggers include trauma,
viral infection, medication, hearing loss, neurotoxicity, and somatic influences (eg, dental procedure or cervical damage);
psychologic triggers sometimes important; stress management critical to managing tinnitus
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| Assessment: audiography; severity scale (for tracking response to treatment); psychologic screening; tinnitus matching
(often not useful); loudness discomfort level (rarely used, due to medicolegal issues); noise masking; otoacoustic emissions
testing for patients with intact hearing (to assess subclinical damage to peripheral auditory system); ultrahigh-frequency
testing; auditory reflex testing (use with caution); repetitive transcranial magnetic stimulation
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| General approach to counseling: demystifying tinnitus through education key; tinnitus not likely to progress (concern
of most patients); habituation usually occurs with time; patients can learn to adjust their reactions to tinnitus
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| Management: approaches include amplification (hearing aid), acoustic desensitization, masking (rarely effective on its
own), and cognitive behavioral therapy; tinnitus retraining—combination of directive counseling and auditory therapy
(eg, adding low-level noise); hearing aids—may mask tinnitus; more commonly, reduce contrast between tinnitus and silence;
increase neural activity to cortex, possibly reducing perception of tinnitus; reduce fatigue and stress in patients with
hearing loss, thereby improving ability to manage tinnitus
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| Central involvement: tinnitus generally persists after severing auditory nerve; although problem begins in periphery,
cortex interprets problem, hippocampus identifies source of signal, and amygdala determines appropriate reaction; normally,
brain suppresses irrelevant stimulation (not so in tinnitus); perceived danger triggers response, regardless of
strength of signal; conditioning may intensify reaction by focusing on signal; behavior modification and retraining can alter
reaction to tinnitus
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| Neuromonics acoustic desensitization protocol: combination of tinnitus retraining therapy, cognitive therapy, and
music; music—4 classical pieces (selected for rhythm, tempo, and amplitude fluctuations) filtered to adjust for hearing
loss, and presented through high-fidelity headphones; initially, noise mixed into signal (later withdrawn, leaving only
music); modified version—can use MP3 player, equalizing signal to boost treble for patients with mild high-frequency
hearing loss; playlist provided; other applications—patients with hypersensitivity problems (eg, loudness recruitment)
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| Defining improvement: reduction in frequency and duration of tinnitus rather than loudness; improved function and
stress management; counseling patients—reassure patient tinnitus probably normal consequence of hearing loss, not
sign of grave illness or impending deafness, and will not get worse; work with sleep pattern; tinnitus real and permanent,
but patient’s reaction need not be permanent; counsel against use of Internet tinnitus chat rooms
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Suggested Reading
Bird PA et al: Intratympanic versus intravenous delivery of methylprednisolone to cochlear perilymph. Otol Neurotol
28:1124, 2007; Boleas-Aguirre MS et al: Longitudinal results with intratympanic dexamethasone in the treatment of
Meniere’s disease. Otol Neurotol 29:33, 2008; Daldal A et al: The protective effect of intratympanic dexamethasone on
cisplatin-induced ototoxicity in guinea pigs. Otolaryngol Head Neck Surg 137:747, 2007; Darlington CL, Smith PF:
Drug treatments for tinnitus. Prog Brain Res 166:249, 2007; Davis PB et al: Neuromonics tinnitus treatment: third clinical
trial. Ear Hear 28:242, 2007; Gantz BJ et al: Acoustic plus electric speech processing: preliminary results of a multicenter
clinical trial of the Iowa/Nucleus hybrid implant. Audiol Neurotol 11(Suppl 1):63, 2006; Hinohira Y et al:
Improvements to staged canal wall up tympanoplasty for middle ear cholesteatoma. Otolaryngol Head Neck Surg 137:913,
2007; Jastreboff PJ: Tinnitus retraining therapy. Prog Brain Res 166:415, 2007; Jenkins HA et al: US phase I preliminary
results of use of the Otologics MET fully-implantable ossicular stimulator. Otolaryngol Head Neck Surg 137:206,
2007; Jeunen G et al: The value of magnetic resonance imaging in the diagnosis of residual or recurrent acquired cholesteatoma
after canal wall-up tympanoplasty. Otol Neurotol 29:16, 2008; Luetje CM et al: Hybrid cochlear implantation:
clinical results and critical review in 13 cases. Otol Neurotol 28:473, 2007; Vikram BK et al: Complications in
primary and secondary acquired cholesteatoma: a prospective comparative study of 62 ears. Am J Otolaryngol 29:1, 2008.
Educational Objectives
| The goal of this program is to improve the management of hearing loss by updating the clinician about advances
in otology and neurotology. After hearing and assimilating this program, the clinician will be better able to:
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 | 1. Compare canal-wall up and canal-wall down techniques for removing cholesteatomas.
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| 2. Discuss current applications of intratympanic pharmacotherapies.
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| 3. Review the advantages and disadvantages of implantable hearing devices.
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| 4. Identify candidates for hybrid cochlear implants.
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| 5. Design an integrated management plan for patients with tinnitus.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning
committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of interest.
Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary
business or commercial interest. For this program, the faculty and planning committee reported nothing to disclose.
Acknowledgments
Drs. Lalwani, Lustig, and Sweetow were recorded at UCSF Otolaryngology Update: 2007, presented by University of California,
San Francisco, School of Medicine, Department of Otolaryngology–Head and Neck Surgery, and held November 8-
10, 2007, in San Francisco, CA. The Audio-Digest Foundation thanks the speakers and the sponsor for their cooperation in
the production of this program.
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