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  TITLE:   OSSICULAR CHAIN RECONSTRUCTION
  SOURCE:  Dept. of Otolaryngology, UTMB, Grand Rounds
  DATE:    JANUARY 26, 1994
  RESIDENT PHYSICIAN:     KATHLEEN McDONALD, M.D.
  FACULTY:                JEFF VRABEC, M.D.
  DATABASE ADMINISTRATOR: Melinda McCracken, M.S.
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  "This material was prepared by resident physicians in partial fulfillment 
  of educational requirements established for the Postgraduate Training 
  Program of the UTMB Department of Otolaryngology/Head and Neck Surgery 
  and was not intended for clinical use in its present form.  It was 
  prepared for the purpose of stimulating group discussion in a conference 
  setting.  No warranties, either express or implied, are made with respect 
  to its accuracy, completeness, or timeliness.  The material does not 
  necessarily reflect the current or past opinions of members of the UTMB 
  faculty and should not be used for purposes of diagnosis or treatment 
  without consulting appropriate literature sources and informed 
  professional opinion." 

     
 INTRODUCTION:
 
      Ossicular chain reconstruction is the rebuilding of the
 middle ear ossicular chain which has been disrupted or destroyed through
 the use of some interpositioned device.  This is to regain the original
 mechanics of the ossicular chain and convert this mechanical energy into
 the electrical impulse produced by the cochlea.  There are three main
 categories of ossicular defects that prevent the transmission of sound
 pressure across the middle ear: 
 
 1. loss of ossicular continuity as with traumatic dislocation, surgical 
    or middle ear pathology such as cholesteatoma; 
 
 2. fixation of the ossicles as with otosclerosis or myringostapediopexy; 
 
 3. a combination of the two.  This paper will go over the different types 
    of prosthesis used, surgical technique and outcome.
      
 HISTORY: 1964 -1987 the main reconstructive material was homograft
 ossicles.  At first, the incus body was mearly repositioned on the head of
 the stapes or stapedial footplate.  Over the years the sculpturing of the
 incus evolved.  Two principle types of sculpturing were the notched incus
 with short process, which was used on an intact stapes, and the notched
 incus with long process, which was used not only to replace the incus but
 the stapedial superstructure as well.
      
 MECHANICS: The normal incudo-stapedial joint is subject to high stress.
 This stress is usually easily coped with in the normal ear with its
 synovial joints and supporting ligaments, but reconstruction introduces
 new geometry and interfaces.  The study by Lesser found that the stress
 levels at the implant-stapedial joint increases as the prosthesis is
 gradually moved down the malleus.  On the other hand, there is some
 evidence that there is an increase in sound transmission as the implant is
 moved down the malleus.  Achievement of the piston-like movement of the
 stapes footplate proved to be the most effective in producing displacement
 of the vestibular fluids.  Ossicular reconstructions which produce tilting
 of the stapes induce markedly less movement of vestibular fluids.
 Transmission of lower frequency stimuli is more efficient than for the
 higher frequencies.  In the malleus-stapes assembly reconstructions the
 position of the prosthesis is critical- the smaller the angle between the
 resolved components of the applied forces the greater the efficiency of
 transmission.  With the columellar systems the site of contact on the
 footplate is less critical to the magnitude of transmission, than the
 tension of the prosthesis.  This is seen in the ear where the malleus lies
 very anteriorly thus unavoidably angulating the prosthesis.  It also
 provides the explanation for the observation that a prosthesis place
 between the stapes head and the tympanic membrane (providing direct
 transmission from the TM to the stapes footplate) often produces better
 results.
      
 SYNTHETIC PROSTHESIS: Increased concern about the use of human donor
 tissue for biological implant led to the search for totally synthetic
 prosthesis for middle ear reconstruction.  This has been the result of
 increased awareness regarding the use of human banked tissue and the
 possibility of transmitting acquired immune deficiency syndrome or other
 infectious diseases.  In 1989, a survey of the American Otological Society
 showed that autograft bone and cartilage, homograft bone and cartilage,
 and Plasti-Pore PORPs and TORPs (which require a cartilage interface) were
 the most common types of implants used.  Of these nine prosthesis, six
 required the use of human tissue.  Despite no documented case of AIDS
 virus being transmitted through the use of homograft bone or cartilage the
 search for totally synthetic prosthesis was undertaken.  The synthetic
 prosthesis should ideally exhibit four basic characteristics.  It should
 be biocompatible, readily available, technically easy to use, and give the
 most advantageous hearing results possible.  Plasti-Pore prosthesis by
 Smith + Nephew Richards was developed  The Plasti-Pore is porous
 polyethylene which is biocompatible material in the middle ear, except
 when it touches the tympanic membrane directly.  It was commonly used
 synthetic prosthesis but required homograft or autograft cartilage
 interface to prevent extrusion.  Therefore, in 1986, the Richards Medical
 Company developed the hydroxylapatite prosthesis.  Prior the advent of
 hydroxyapatite, Plasti-Pore was the most frequently used synthetic
 material for hearing reconstruction.  The hydroxyapatite has
 characteristics of its bony counterparts and was used in the same fashion
 with an "incus interposition prosthesis" and "incus-stapes prosthesis."
 Hydroxylapatite belongs to a family of materials know as calcium phosphate
 ceramics.  These are among the most biocompatible materials available
 today.  Their elemental constituents closely resemble those of the mineral
 matrix of human bone.  Hydroxyapatite displays the same crystal structure
 as human bone.  These two previously mentioned characteristics account for
 its biocompatibility.  Living bone has been found to form a chemical bond
 to the surface of hydroxyapatite.  It is also seen that there is little-
 to-no biodegradation insitu.  Hydroxyapatite can be used directly against
 the tympanic membrane or tympanic membrane graft without the need for any
 cartilage or other tissue as an interface, unlike the previous material
 Plasti-pore which requires cartilage interface.  Grote was the first to
 report the clinical use of hydroxyapatite in middle ear reconstruction,
 and has reported excellent long-term hearing results.  Multiple prosthesis
 have been developed by Wehrs, Black Applebaum, and Goldenberg to name a
 few, most of which have found good long term hearing results.
 Hydroxyapatite has many of the ideal characteristics required to be a good
 prosthesis.  It is extremely biocompatible and exhibits a very low
 extrusion rate.  In a study by Goldenberg with 157 consecutive cases he
 found a very low extrusion rate for hydroxyapatite 2.6% when compared to
 Plasti-Pore at 6.5% and the homograft at 0%.  With the hydroxyapatite most
 where seen in revision surgery for cholesteatoma where retraction and
 atelectatic tympanic membranes were present and still resulted in low
 extrusion.  It is readily available as a biomaterial and may be shaped and
 molded by the manufacture into appropriate configurations.  It exhibits no
 problem with antigenicity or transmittal of disease.   Hearing results are
 comparable to other prosthesis (68-90% depending on the prosthesis type.)
 Using the criteria of Brackmann, an audiological successful result was
 defined as a postoperative air bone gap (residual conductive deficit) of
 15 dB or less when a PORP or incus prosthesis was placed or a 25 dB or
 less closure using a TORP or incus-stapes prosthesis.  However,
 hydroxyapatite is technically difficult to use intraoperatively because it
 is brittle and shatters easily when drilled or trimmed with a sharp
 instrument.  To get around this Plasti-Pore has been used as the shaft to
 fit onto the capitulum or footplate and the hydroxyapatite head which
 comes in contact with the tympanic membrane.  Plasti-Pore is easy to trim
 to desired configuration intraoperatively.  Goldenberg initially developed
 this modification.
      
 OUTCOME: Elimination of residual or recurrent disease is the primary
 prerequisite for ossicular reconstruction.  A frequent reason for
 reconstruction is the destruction of the ossicles from chronic infection
 and cholesteatoma.  This must be eradicated if the reconstruction is to be
 a success.  The surgeon must start by identifying the anatomical,
 pathological and functional situations involved with the patients ear
 which will be necessary to pick the proper prosthesis and timing of the
 surgery.  The anatomical factors to consider are the relation of the drum
 to ossicular remnant, the stapes profile and the angle between stapes and
 malleus handle.  Pathological factors with the type of ossicular defect,
 the lining of middle ear and function of the eustachian tube all need to
 be considered.  Otologist have lacked a detailed ability to assess the
 preoperatively the fate of an ossiculoplasty.  A study by Black looked
 into significant adverse clinical features to more accurately evaluate
 "risk content." It was found that five types of influences may complicate
 an ossiculoplasty: surgical, prosthetic, infection, tissue, and eustachian
 (the SPITE factors.) Previously the Otologist had limited methods of
 comparing the pathologic basis of ossiculoplasty.  Those included the
 Bellucci classification and Austin's ossicular classification.  The
 Bellucci system described the state of infection: 1. never infected; 2.
 intermittent discharge; 3. unremitting discharge, and 4. cleft palate and
 nasopharyngeal deformities.  The other classification is Austin's
 ossicular classification which is simple but an effective description of
 the status of the chain but, does not address the problem of the
 suitability of the malleus to receive a malleus-to-stapes assembly, or the
 problem of the fixed footplate.  Austin defines four types of ossicular
 defects depending on the presence or absence of malleus handle and
 stapedial arch.  In SPITE the first area to look at is the surgical skill
 of the surgeon and the complexity of the case.  This spills over into the
 type of defect present, therefore, the type of prosthesis needed for the
 different situations can affect hearing outcome.  The third area that is
 looked at by the SPITE criteria is infection such as unremitting otorrhea
 and it appears to have the highest adverse effect on outcome.  Tissue
 factors influence success.  It has been separated into vitality - general
 health condition of the patient, and dynamics - preoperative mucosal
 quality.  Eustachian tube dysfunction with effusion and atelectatic
 membranes point towards poor results.  The data attained from this will
 help in the assessment of patients and their likely outcome, but will also
 allow for comparisons between studies.  Results can be improved by
 awareness of the possibilities for reconstruction and making best use of
 available prosthesis.  The principles applied to improving tympanoplasties
 can contribute to ossiculoplasty success by preventing atelectasis or
 lateralization; these include graft placement, grommet insertion, silastic
 sheeting and staging.  One stage procedures should only be attempted in
 cases with intact tympanic membranes or intact and mobile stapes with a
 stable malleus and tympanic membrane remnants with no mucosal disease.  A
 study by Seife from Egypt, showed extensive incudal losses which was
 reconstructed with an interposition graft initially showed encouraging
 results with satisfactory closure (air bone Gap to 10- 20 dB) in 80.4%
 However, this deteriorated with time.  The problem with this technique is
 that the incus is not securely placed and may abutt against facial canal
 or promontory.  There is also a tendency for the graft to pull away from
 the incus or to separate it from the stapes.  Obstruction to aeration
 caused by the bulk of the incus may contribute to continued infection.
 The malleus stapes assembly circumvents the incus interposition problems
 and gave satisfactory results in 85.7%.  The problem with this assembly is
 that it does not allow for efficient sound transmission as the angle
 between the malleus and the stapes gets bigger.  In such situation the
 notched incus prosthesis or a PORP yields better results.  The malleus
 footplate assembly a satisfactory result was obtained in 80% of cases with
 60% excellent results (< 10 dB AB Gap).  Failures are due to inadequate
 length or to encroachment by the margins of the oval window.  Absence of
 the malleus handle poses a special problem as there is nothing to
 stabilize the graft tympanic membrane, which tends to pull away from the
 repositioned ossicle.  Staging is desirable in this situation and this
 author found that the Schuring ossicle cup prosthesis is suitable yet
 results are not perfect.  Total loss of the ossicular chain poses a very
 difficult problem with reconstruction.  Cartilage seems to provide the
 best results offering the ability to get the desired length, low frequency
 to extrude or to ankylose to the oval window niche.  TORPS initially
 showed encouraging results of 84.6% satisfactory hearing which
 deteriorated with time to 51%.
      
 HEARING EVALUATION: The danger of too early evaluation of hearing results
 in terms of air-bone gap closure can not be over emphasized.  There is
 continued hearing loss over time irrespective of the type of
 reconstruction employed.  Most reports on the success or failure of
 reconstruction of the ossicular chain employ air bone gap closure.  This
 is useful information when comparing the performance of one material to
 another, but it may be inappropriate from the point of view of the
 patient.  Improvement of the patient's overall auditory performance is the
 aim of ossiculoplasty and this is what reduces the patients auditory
 disability not the closure of an air bone gap.  In general the degree of
 disability is determined by the status of the better ear.  The ideal of
 bilateral normal hearing is often unattainable, and so in advising
 patients regarding surgery for hearing gain it is important not to forget
 the contribution of the other ear.  In most cases the proposed surgery the
 worst ear is selected, but unless the this can restore symmetrical or
 nearly symmetrical hearing, or convert the operated ear into the better
 ear, the patient is unlikely to experience a reduction in disability.  The
 requirements for patient benefits to be achieved the postoperative air
 conduction average over the speech frequencies (0.5, 1, 2, and 4 KHz) must
 be <30 dB or the interaural difference reduced to < 15 dB.  15dB
 corresponds to the cross-attenuation effect of the skull.
      
 SURGICAL TECHNIQUE:
      
 INCUS REPLACEMENT PROSTHESIS: Incus replacement prosthesis is used in
 defects in the ossicular chain due to incus pathology.  In replacement of
 the incus the stapes must be prepared.  If the lenticular process of the
 incus is attached it must be removed or left inplace if the stapes is
 extremely mobile to prevent trauma to the inner ear.  It is important to
 remove all squamous epithelium, scar tissue, and mucous membrane.   The
 distance between the head of the stapes and malleus is evaluated.  A
 single notched incus replacement is used unless the malleus is directly
 over the stapes or extremely far forward.  80% of the cases the height is
 2-3mm.  The prosthesis is introduced lying on its side on the promontory
 with the notch just off the tip of the malleus and the hole in the base
 near the stapes head.  With a right angled pick, the manubrium of the
 malleus is elevated and the body of the prosthesis is engaged with a
 gently curved pick the notch is slid up along the undersurface of the
 malleus.  The hole in the prosthesis should then engage the stapedial
 head.  the prosthesis is adjusted until it is vertical to the stapes and
 appears stable.  Is should be slightly loose, if wedged to tightly it will
 have insufficient movement and not produce good hearing results.
      
 INCUS-STAPES PROSTHESIS: Incus-stapes prosthesis is used to reconstruct
 the ossicles when the stapes superstructure is absent.  The stapes
 footplate should be evaluated to determine mobility and any scar or mucosa
 should be removed.  The height between the malleus and the footplate
 determines the length of the prosthesis and the distance from the center
 of the stapes to the malleus determines the position of the notch.  80% of
 the prosthesis are single notched.  The prosthesis is place on the
 promontory with the shaft on the implant on the stapedial footplate and
 the notch off the tip of the malleus.  With the right angle pick, the
 manubrium of the malleus is elevated, and a gentle curved pick is placed
 under the implant. The notch is slid up on the malleus.  The surgeon
 should be extremely careful not to exert undue pressure on the stapedial
 footplate or wedge the prosthesis tightly in place. Again it should be
 loose, yet not fall over without support.  The long process should be
 centered on the stapedial footplate by advancing it toward the anterior
 crus.  This maneuver will secure a prosthesis that appears slightly to
 loose.  A prosthesis that is a little too long, tends to tip forward and
 the long process will be on the posterior part of the footplate.  This
 prosthesis should be removed and no attempt at forcing the prosthesis in
 place because it will fracture or dislocate the footplate.
      
 MALLEAR DEFECTS: The malleus head may be fixed in the epitympanum which
 will decrease the mobility of the ossicular chain.  Management consist of
 first separating the incudostapedial joint to prevent inner ear injury.
 Next, the mobility of the stapes is ascertained to be sure it is not
 fixed.  The incudomallear joint is engaged with a right angle pick, and
 the incus is mobilized and remove. After exposing the head of the malleus
 its short process is removed with a malleus nipper.  The ossicular chain
 is then rebuilt with the incus replacement prosthesis.  Another mallear
 defect is erosion and shortening of the manubrium of the malleus.  Often
 the incus is normal and mobile.  In this situation it is recommended that
 the incus be removed as well as the head of the malleus and the neck.
 Reconstruction is carried out with homograft malleus and incus prosthesis.
 A two stage operation is recommended since the tensor tympani tendon is no
 longer present to stabilize and the malleus will not be secure.
      
 COMBINED DEFECTS OF MALLEUS AND OSSICLES: Erosion of the incus and loss of
 the stapes superstructure constitute the most common multiple defect of
 the ossicular chain.  This requires the incus-stapes prosthesis.   Another
 is a completely fixed ossicular chain.  First the incudostapedial joint
 must be separated.  If the stapes is fixed this requires a stapedotomy.
 When the stapes is mobile, the incus should be removed and the mobility of
 the malleus is ascertained.  If mobile the incus prosthesis will due it
 not it must be removed.  The most severe is the loss of all ossicles
 except the footplate which occurs with cholesteatoma.  These can be
 rebuilt with homograft malleus and tympanic membrane and IS prosthesis.
 PORPS can are frequently used in this situation.
      
 COMPLICATION: Intraoperative immediate complication consist of using a
 prosthesis with too much height or forcing it into place.  With the incus
 prosthesis it could result in fracture of the stapes superstructure,
 dislocation of the stapes, tear of the annular ligament with a
 perilymphatic fistula, severe or total SNHL.  With the incus-stapes
 prosthesis complication could consist of stapedial footplate fracture or
 pushing the footplate into the vestibule.  To prevent these complications
 the prosthesis must be handled gently and sudden undue pressure avoided.
 If a resulting tear in the annular ligament or crack in the footplate
 occurs, a tissue seal of fat or fascia should be place as a seal.  The
 ossicular reconstruction must be aborted at that time with a second stage
 done at later date.  Immediate post operative complication might be
 vertigo which is related to unrecognized oval window trauma.  If the
 reconstruction was difficult, the possibility of perilymph fistula is
 possible.  Exploration may be necessary if conservative therapy fails to
 resolve symptoms.  Potential delayed postoperative complications might be
 erosion or extrusion of the prosthesis.  The cause may be recurrent middle
 ear cholesteatoma, poor skin or tympanic membrane.  If this occurs and the
 hearing remains good, the surgeon may elevate the tympanomeatal flap and
 carry the elevation over the prosthesis leaving a perforation that can be
 fixed by conventional means.  If hearing is poor the prosthesis should be
 removed and replaced.
      
 STAPES REPLACEMENT: INTRODUCTION: Otosclerosis is an abnormal resorption
 and deposition of bone in the labyrinthine capsule and the middle ear.  It
 is noted in 1% of the white population and is primarily transmitted
 autosomal dominant with incomplete penetrance.  Carhart's notch is a 10-30
 dB loss in bone conduction at 2000Hz is presumed to be secondary to
 stapedial fixation.  This disease is the most common cause of stapes
 fixation.
      
 HISTORY: Shea in the late 50's replaced the stapes with a polyethylene
 prosthesis and a vein graft for coverage of the oval window.  Schuknecht
 modified this procedure to combined fat or connective tissue and wire
 prosthesis.  House, in 1962, started using gelatin sponge to rest the wire
 prosthesis which has not been used due to the increased risk of granuloma
 formation.  Hough, describe the anterior crurotomy technique.
      
  SURGICAL TECHNIQUE:  A standard tympanomeatal flap is elevated.
 Usually the scutum area of bone must be removed with a curet to expose the
 oval window and stapes superstructure.  The surgeon assess the mobility of
 the ossicular chain, and the stapes footplate region is then inspected to
 confirm footplate fixation from the otosclerotic lesion.  Various
 techniques are preformed to mobilize the stapes.  Anterior crurotomy with
 partial stapedectomy involves the removal of the anterior footplate and
 the anterior crus.  This is good for patients with isolated anterior
 fixation.  The footplate is fractured in the midportion and only the
 anterior half is removed.  A connective tissue graft is then placed over
 the exposed area.  The incudostapedial joint is left intact and stapedial
 tendon is left undivided.  In many patients more extensive disease is
 present and complete stapedectomy or stapedotomy is needed.  Then the
 stapedial tendon with a sharp instrument is severed and a control hole in
 the footplate is made prior to separation of the incudostapedial joint.
 The superstructure of the stapes is fractured and extracted.  The entire
 footplate is then removed in a piece meal fashion using small hooks. The
 oval window is sealed with a graft and the prosthesis is place.  In
 obliterative otosclerosis removal of the footplate is not feasible due to
 severe fixation.  A fine microstapes drill is used to place a 0.8 to 1 mm
 opening which allows a prosthesis to be place over a connective tissue
 graft.  Stapedotomy is now used on less severe cases with good surgical
 results.  The surgical technique is to created a fenestra in the
 midportion of the stapes using a drill, pick or laser.  A piston
 prosthesis is then positioned and connective tissue is placed to prevent
 fistula.  This technique has show less frequency of postoperative cochlear
 deafness and improved AB gap closure at 2000 Hz.
      
 PROSTHESIS: A variety of prosthesis have been developed.  Earlier
 prosthesis with a sharp or beveled end have been found to cause
 postoperative fistulas and are not used.  House gelatin sponge wire
 prosthesis is not use due to the increased risk for reparative granulomas.
 The design that has proven itself is the wire prosthesis and connective
 tissue graft.  The prosthesis design includes a wire crimped tightly
 around the incus, a wire teflon piston, and a Robinson-type bucket handle.
      
 POSTOPERATIVE RESULTS: Postoperative hearing result reveal
 closure of the AB gap to within 10 dB or the preoperative bone conduction
 level in about 90% of the patients.  Ten percent of the patients
 experience no improvement in hearing and some postoperative cochlear loss
 (3 percent persistent profound SNHL).  Postoperative follow up suggest a
 progressive high-frequency SNHL in some post stapedectomy patients.  It
 still remains unclear whether this is due to cochlear otosclerosis or
 long- term postsurgical effect.
      
 COMPLICATING FACTORS: Anatomical variations such as aberrant jugular bulb
 and stapedial artery causing bleeding.  Profuse perilymph gusher found in
 patients with cochlear aqueduct seen with congenital footplate fixation.
 Fracture of the long process of the incus can occur.  A floating footplate
 which requires a control hole to be placed and the  use of a small hook to
 remove the footplate.  If it becomes severely depressed into the vestibule
 and surgical attempts at removal should be avoided due to the high
 incidence of cochlear deafness.  Revision stapedectomy is needed with
 prosthesis failure due to displacement or incus tip erosion.  Other
 failures are footplate refixation, perilymph fistula, otosclerotic
 regrowth, and lateralization of the oval window membrane.  This procedure
 improves the patient in less than 65% of the cases and postoperative
 cochlear deafness is 7x more prevalent.
      
 COMPLICATIONS: The primary risk of stapedectomy is postoperative cochlear
 deafness (1-3%)  Postoperative balance disorders are usually transitory
 but occasionally can be persistent. Also altered taste, tympanic
 perforation, facial nerve injury. Tinnitus following stapedectomy is
 somewhat unpredictable and is not necessarily related to the success of
 the procedure.
      
 CONCLUSION: There are many different prosthesis and techniques to use to
 reconstruct the middle ear ossicles.  It is also changing with the
 development of new synthetic materials and alterations of old techniques.
 The ossicular chain reconstruction is a good procedure which is very
 beneficial to many patients. 
      
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                              BIBLIOGRAPHY    
      
 Applebaum, EL. "An Hydroxyapatite Prosthesis for Defects of the Incus Long
 Process." LARYNGOSCOPE, 103; March 1993: 330-332.
           
 Bailey BJ. Head and Neck Surgery - Otolaryngology, Vol II: J.B.
 Lippincott. 1993: 1667-1675.
      
 Black B. "Ossiculoplasty Prognosis: The SPITE Method of Assessment." THE
 AMERICAN JOUNRNAL OF OTOLOGY, 13(6); November 1992: 544-551.
      
 Goldenberg, RA. "Hydroxylapatite Ossicular Replacement Prosthesis: Results
 in 157 Consecutive Cases." LARNYGOSCOPE, 102; October 1992: 1091- 1096.
           
 Goldenberg, RA. "Hydroxylapatite ossicular Replacement Prosthesis: A
 Four-year Experience." OTOLARYNGOLOGY- HEAD AND NECK SURGERY, 106; March
 1992: 261-269.
      
 House JW. "Stapedectomy Technique." OTOLARYNGOLOGY CLIN NORTH AMERICA,
 26(3); June 1993: 389-93.
      
 Lesser TH. "Mechanics and Materials in Middle Ear Reconstuction." CLIN
 OTOLARYGOL, 16; 1991: 29-32.
      
 Nikolaou A. "Ossiculoplasty with the use of autografts and synthetic
 prosthetic materials: A comparison of results in 165 cases." THE JOURNAL
 OF LARYNGOLOGY AND OTOLOGY, 22; April 1992: 692- 694.
      
 Seifi EL. "Options in Ossiculoplasy." EAR NOSE AND THROAT JOURNAL, 70(11);
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 Toner JC. "Realities in Ossiculoplasy." JOURNAL OF LARYNGOLOGY AND
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