Reconstructing the absent lenticular process

When a surgeon encounters an absent lenticular process of the incus, he must either reposition the incus or attempt to bridge the small gap between the remaining incus long process and the stapes capitulum. Our solution to this problem is to place a Lippy modified Robinson stapes prosthesis on the stapes footplate and attach it to the remaining long process, thus bypassing the stapes superstructure. This modified Robinson prosthesis has a portion of the well removed allowing the eroded long process to enter from the side. The hearing results of 63 cases at 6 months (two-thirds of which had a concurrent tympanoplasty) are 67% within 10 dB and 91% within 20 dB of the preoperative bone hearing level. The use of an existing and proven prosthesis provides both stability and, to date, the most successful hearing results for reconstructing the absent lenticular process.     

Stapedectomy for otosclerosis with malleus fixation

Malleus fixation, in addition to stapes fixation, presents a perplexing surgical problem. Should the incus replacement prosthesis procedure be performed or only a stapedectomy? The hearing results of a stapedectomy alone in 45 cases with both stapes and malleus fixation are 70% within 10 dB and 84% within 20 dB of the preoperative bone conduction hearing level.     

First experience with a new stapes clip piston in stapedotomy.

OBJECTIVE: Hearing results after 23 implantations of a newly designed titanium-clip stapes piston prosthesis (the àWengen Clip Piston prosthesis) in patients with otosclerosis were evaluated. This new type of stapes piston was designed to avoid the crimping onto the incus in stapedotomy. This one clip fits all designs and enables solid fixation by clicking the prosthesis onto the long process of the incus without crimping. STUDY DESIGN: A retrospective pilot study was carried out by microcomputer of the preoperative and postoperative audiological results of patients in whom the titanium-clip stapes piston prosthesis was implanted. SETTING: Ear, nose and throat department of Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. PATIENTS: 23 Patients underwent a stapedotomy for hearing improvement suffering from otosclerosis. implantations of a newly designed titanium-clip stapes piston prosthesis (the àWengen Clip Piston prosthesis) in patients with otosclerosis were evaluated. INTERVENTION(S): The stapedotomy was performed with the àWengen Clip Piston prosthesis. MAIN OUTCOME MEASURE(S): Pre and postoperative audiograms were used to evaluate the hearing gain improvement with the new stapes piston. Especially we looked at the airbone gap closure and the sensorineural hearing after the surgical procedure and compared these with the ones before surgery. RESULTS: The hearing results showed a closure of the pure-tone average air-bone gap to within 10 dB in 56.6% of cases (10 of 23 implantations) and to within 20 dB in 100% (23 of 23 implantations). A residual air-bone gap of greater than 20 dB was seen in the present pilot study. Postoperative overclosure of bone-conduction thresholds was discovered only for the frequency of 2 kHz. Sensorineural hearing loss greater than 10% did not occur, and there was no decline in the speech discrimination. CONCLUSIONS: The use of a newly designed titanium-clip stapes piston prosthesis with a diameter of 0.4 mm gives good results in cases of stapedotomy for otosclerosis. The titanium-clip design is a new development in the evolution of stapes piston prostheses. Surgical introduction, placement, and fixation are not always easy, depending on the anatomy of the middle ear and the thickness of the fixation area on the long process of the incus.     

镫骨足弓进行性萎缩和镫骨足弓鼓岬粘连

目的介绍二种少见镫骨病变-足弓与鼓岬粘连和足弓萎缩引起传导性耳聋及其处理的结果.方法例1,女性17岁,右耳进行性听力下降伴耳鸣2年半.手术见镫骨头在颈部与足弓脱离,足板活动,镫骨苍白.取耳道薄骨片,修成叉柱状,尖抵足板,紧贴足弓叉起砧骨长突.术后语言频率(0.5-2KHz)气骨导差闭合到10dB以内.例2男性16岁,右耳非渐进耳聋3年.手术见砧骨长突较长,镫骨与砧骨豆状突连接紧密,但镫骨过于倾斜,足弓与卵圆窗下缘的鼓岬紧贴粘连,致镫骨活动受限.分离砧镫关节,切断镫骨肌,分离粘连,将镫骨足弓向上方移位并抬高.术后气骨导差闭合.结果分别在2年和1年后随访,听力保持术后水平.结论镫足弓进行性萎缩可能是局部缺血所致退行变,镫骨弓与鼓岬粘连可能是先天解剖变异加上后天炎症肿胀引起,临床上都少见.用不切开足板的微创方法解决青少年镫骨病变较为有利.     

Stapes prosthesis attachment: the effect of crimping on sound transfer in otosclerosis surgery

OBJECTIVES/HYPOTHESIS: Although in stapes surgery successful hearing improvement may be achieved in the majority of patients, unsatisfactory closure of the air-bone gap can be recorded. One of many reasons for unexpected failures of stapes surgery may be the insufficient crimping of a stapes prosthesis onto the incus. The objectives of the study were to assess the amount of sound transmission loss in response to the quality of prosthesis crimping and to identify a required loop attachment pattern to obtain good sound transmission results. STUDY DESIGN: Experimental. METHODS: A temporal bone model was developed to measure the sound transmission properties between incus and prosthesis on 17 fresh human temporal bones. The attachment of a titanium stapes piston was assessed without crimping, followed by loose crimping and tight fixation to the incus, using scanning laser Doppler interferometry, endoscopic photography, micro grinding technique, and scanning electron microscopy. An algorithm had to be developed to simulate acoustical stimulation using electromechanical stimulation. RESULTS: Optimal tight crimping of the stapes piston revealed consistent good sound transfer function ranging from 0 to 7 dB loss, and loss remained, on average, at 2 dB. The mean transmission losses for conditions of loose crimping and no crimping were surprisingly small (within 10 dB). However, these unusual crimping conditions allowed a wide range of losses up to 28 dB. A close coupling at least at two opposite points was obligatory to obtain consistently good results. CONCLUSIONS: Perfect hearing reconstruction necessitates ideal crimping of a prosthesis to obtain consistently good results. However, the final functional gain depends on many different intraoperative and postoperative factors.     

Ossiculoplasty with a cartilage-connecting hydroxyapatite prosthesis for tympanosclerotic stapes fixation

Many cases of tympanosclerotic stapes fixation are accompanied by fixation or erosion of malleus and/or incus. This status of the ossicular chain is one of the reasons that ossiculoplasty for tympanosclerotic stapes fixation is more difficult than that for otosclerosis. We conducted a retrospective review of seven patients who were operated on for tympanosclerotic stapes fixation between 2002 and 2006. All of the patients had abnormal conditions of the malleus and/or incus and underwent stapedectomy and total ossiculoplasty with hydroxyapatite prosthesis (Apaceram T-7 type), which has a planar-like head portion that contacts a piece of cartilage. Postoperative hearing results were assessed in all seven patients after at least 1 year. The postoperative air-bone gap (ABG) was closed within 10 dB in two of seven patients, and was less than 20 dB in six of seven patients. The mean postoperative ABG was closed within 10 dB at 1 and 2 kHz and less than 20 dB at low frequencies (0.25 and 0.5 Hz). There was almost no hearing improvement at high frequencies (4 and 8 kHz). There were no patients with postoperative sensorineural hearing loss. The present study shows that stapedectomy and total ossiculoplasty with cartilage-connecting hydroxyapatite prosthesis is effective and safe for stapes fixation accompanied by fixation or erosion of the malleus and/or incus.     

Malleus-stapes assembly: experience with two prostheses

Tympanoplasty is often a necessary part of middle-ear surgery, the most common defect being that between an intact, mobile stapes and the malleus handle. The most readily available tissue is the patient's incus, reshaped to bridge the space between an intact stapes and the malleus. When the incus cannot be used, the hydroxyapatite Wehrs incus prosthesis can be used as an alternative.Twenty-six patients had an autograft incus ossiculoplasty and 20 patients underwent modified Wehrs incus prosthesis ossiculoplasty. The average post-operative air-bone gaps (ABGs) were 16.2 dB hearing loss (dBHL) and 17.2 dBHL, respectively. Air-bone gap closure to within 15 dBHL was achieved for 48 per cent of incus autografts and for 57 per cent of Wehrs prostheses, and to within 20 dBHL for 77 per cent and 62 per cent, respectively. Over four years follow up, the reconstruction was stable for each group, the ABGs being 17.7 dBHL and 17.1 dBHL, respectively.     

Reconstruction of the ossicular chain with hydroxyapatite prostheses

To achieve a lasting result in reconstruction of the ossicular chain, strict material and surgical criteria must be combined. The best biomaterial, apart from bone, is hydroxyapatite, the mineral matrix of living bone tissue. For the reconstruction, the assembly technique is used instead of a columella. Direct contact with the drum membrane is not reliable if a columella is used, and extrusion or lateralization may influence postoperative results. In the case of a missing incus, an assembly prosthesis of dense hydroxyapatite is placed on top of the stapes head and the handle of the malleus, in a pocket between drum membrane and the neck of the malleus. Long postoperative follow-up of 120 patients showed an air-bone gap closure within 20 dB for 83.3% of the patients, no extrusion was observed, and the hearing gain stayed constant. Reconstruction of a tympanic membrane perforation and posterior canal wall was performed in the same stage in sixty patients. In the case of a missing incus and stapes superstructure, an incus/stapes prosthesis of dense hydroxyapatite, as assembly between footplate and handle of the malleus, was used. Long postoperative follow-up of twenty-five patients showed an air-bone gap closure within 20 dB for 68% of the patients. Reconstruction of a tympanic membrane perforation and posterior canal wall was performed in sixteen patients. No extrusion was observed and the hearing gain stayed constant. Hydroxyapatite prostheses have proven to be a good alternative for autologous and homologous ossicles.     

Revision stapedectomy

The need for revision stapedectomy surgery still exists despite the many changes that have occurred in the surgical technique for the treatment of stapedial otosclerosis over the past 30 years. Sixty-six revision stapes operations were analyzed to determine the causes of failure of previously operated cases of stapedial otosclerosis, and to evaluate the hearing results following a revision stapedectomy. Failure was most often due to erosion of the incus (41%), displacement of the prosthesis from the incus (24%), or migration of the prosthesis from the center portion of the oval window (24%). Postoperative improvement of hearing was observed in 81% of ears operated on for a conductive hearing loss. Closure to within 10 dB, however, occurred in 61%. Two ears suffered a deterioration in the sensorineural hearing level following the revision surgery. Speech discrimination scores following revision surgery were improved in 5% of ears and unchanged in the remainder. Although the overall hearing results are less favorable than those seen in primary stapedectomy, revision stapedectomy surgery should continue to be offered to patients whose primary stapes surgery failed or whose initial good result declined over time.     

Stapes surgery performed for congenital stapes foot plate fixation--comparison of prosthesis fixation to the malleus vs. the incus

We report the surgical results of stapes surgery using the Schukneht-type wire piston prosthesis performed on 30 ears with fixation of the stapes footplate and absence of the long process of the incus. The prosthesis was reformed to avoid dislocation and fixed to the handle of the malleus. The surgical results in another 49 ears, the comparator group, in which the prosthesis was fixed to the long process of the incus because the anomaly was restricted to fixation of the footplate without other associated anomalies, were also analyzed for comparison. The mean postoperative air conduction hearing levels were 28.6dB in the subjects and 21.6dB in the comparator group, and the mean hearing improvements were 35.7dB and 29.7dB, respectively. The success rate of the operation, based on the criteria established by the Japan Otological Society, was 90% in the subjects and 98% in the comparator group. The mean postoperative air-bone gap in the subjects was 15.8dB, which was 4.3dB higher than that in the comparator group. The difference between the two groups was considered to be due to the difference in the effectiveness of the conduction mechanism after the surgery. We therefore concluded that the surgical procedure using the Schukneht-type wire piston prosthesis to fix the malleus handle is a useful surgical method that yields satisfactory results.     

Stapedectomy outcomes: titanium versus teflon wire prosthesis

OBJECTIVE: To compare the effectiveness of two stapes prostheses in hearing improvement of patients undergoing stapes surgery for otosclerosis. STUDY DESIGN: Retrospective chart review. METHODS: Titanium and Teflon wire stapes prostheses were compared with regard to effectiveness in closing the air-bone gap. The charts of 461 stapedectomies performed by one surgeon from 1996 to 2001 were reviewed. Patients who underwent stapedectomy for reasons other than otosclerosis, revision cases, and those with inadequate preoperative or postoperative bone-conduction threshold data were excluded. Small fenestra technique using either laser or drill was used for all patients. Inclusion criteria were met by 218 patients. Patients were then grouped according to type of prosthesis used, and hearing outcomes were compared. Measured outcomes were four frequency air-bone gap closure, pure-tone threshold, and rate of sensorineural hearing loss (SNHL). RESULTS: The study group was comprised of 35 titanium and 183 Teflon wire prostheses. Closure of the air-bone gap to less than 10 dB was achieved in 86% of the patients with Teflon prosthesis compared with 71% of those with titanium prostheses. The groups were equivalent in regard to site of otosclerotic disease as well as technique, laser or drill, used to create the fenestra. Rate of SNHL was low for both groups and not significantly different. CONCLUSIONS: Both prostheses provided comparable results, although the Teflon platinum wire prosthesis was slightly superior. The smaller numbers in the titanium group may confound these results. The design of the titanium prosthesis provides a crimp that is circumferential around the incus, and that prosthesis was selected in cases with a narrow incus. The selection bias may also influence the results seen in this study.     

Bone Cement Reconstruction of the Ossicular Chain: A Preliminary Report

Objective: To determine the feasibility and efficacy of using a bone cement, Oto-Cem, to reconstruct the ossicular chain. Study Design: Prospective clinical trial on nine consecutively chosen adult patients with ossicular chain defects. Patients and Setting: Nine patients with ossicular chain defects involving the long process of the incus were treated at the Carolina Ear and Hearing Clinic. The ossicular chain was reconstructed using bone cement by itself or in conjunction with a stapes prosthesis. Main Outcome Measures: Preoperative audiograms were compared with audiograms 3, 6, and 12 months after reconstruction. Results: There was a mean pure-tone average (PTA) improvement of 15 dB in patients undergoing incus to stapes suprastructure reconstruction with the bone cement. The incus to mobile footplate reconstruction (using a stapes prosthesis attached to the newly reconstructed incus) resulted in a 34-dB PTA postoperative improvement. Two of the three patients with incus to oval window repairs experienced a 10-dB improvement in PTA. One of the three patients experienced a loss in speech discrimination and a 2-dB loss in PTA. Conclusions: Despite the limited number of patients, this preliminary study demonstrates the effectiveness of Oto-Cem in reconstructing a foreshortened incus. There was a substantial hearing improvement in all but one patient in the incus to stapes or the incus to footplate categories.     

A novel implantable hearing system with direct acoustic cochlear stimulation

A new implantable hearing system, the direct acoustic cochlear stimulator (DACS) is presented. This system is based on the principle of a power-driven stapes prosthesis and intended for the treatment of severe mixed hearing loss due to advanced otosclerosis. It consists of an implantable electromagnetic transducer, which transfers acoustic energy directly to the inner ear, and an audio processor worn externally behind the implanted ear. The device is implanted using a specially developed retromeatal microsurgical approach. After removal of the stapes, a conventional stapes prosthesis is attached to the transducer and placed in the oval window to allow direct acoustical coupling to the perilymph of the inner ear. In order to restore the natural sound transmission of the ossicular chain, a second stapes prosthesis is placed in parallel to the first one into the oval window and attached to the patient's own incus, as in a conventional stapedectomy. Four patients were implanted with an investigational DACS device. The hearing threshold of the implanted ears before implantation ranged from 78 to 101 dB (air conduction, pure tone average, 0.5-4 kHz) with air-bone gaps of 33-44 dB in the same frequency range. Postoperatively, substantial improvements in sound field thresholds, speech intelligibility as well as in the subjective assessment of everyday situations were found in all patients. Two years after the implantations, monosyllabic word recognition scores in quiet at 75 dB improved by 45-100 percent points when using the DACS. Furthermore, hearing thresholds were already improved by the second stapes prosthesis alone by 14-28 dB (pure tone average 0.5-4 kHz, DACS switched off). No device-related serious medical complications occurred and all patients have continued to use their device on a daily basis for over 2 years.     

Total implantation of the active hearing implant TICA for middle ear disease: a temporal bone study

A subpopulation of hearing-impaired patients has conductive hearing loss that cannot be improved by classic tympanoplasty. Other patients have a mixed hearing loss and cannot be helped by present forms of ear surgery or by hearing aids. Possible help for some patients may come from current implantable hearing devices if these are modified for the patient's specific anatomic situation. The TICA LZ 3001 is a hearing implant for total implantation used to treat moderate to severe sensorineural hearing loss. Most patients who use it have a normal ossicular chain that allows coupling of the implant to the incus. The present temporal bone study demonstrates that the TICA can also be used in patients with an interrupted ossicular chain. If the incus long process shows a defect, the TICA may be coupled to the incus body, and connection between the stapes and the long process of the incus can be achieved with a commercially available titanium-angle prosthesis or liquid ionomeric cement. In cases of an absent incus, the coupling axis of the transducer may be coupled to the stapes head via a modified coupling element. With an absent stapes, the coupling axis may be coupled directly to the perilymph by a coupling element similar to a gold stapes prosthesis.     

The use of malleus allografts in ossiculoplasty

OBJECTIVE: To assess the functional performance of remodeled malleus allografts in a malleus-footplate assembly in terms of hearing results and mid long-term stability. STUDY DESIGN: A retrospective study of 60 consecutive patients who underwent a malleus allograft ossiculoplasty from 1993 until 2000. In all cases the incus and the stapedial arch were missing as the result of cholesteatoma (49), chronic otitis (5), incus necrosis resulting from stapes prosthesis (5), and congenital ossicular malformations (1). In all cases malleus allografts were remodeled to form a malleus-stapes assembly. RESULTS: The audiometric results, using such an ossiculoplasty, revealed an overall median gain of 18.3 dB at 2 months, 22.3 dB at 6 months, and 25 dB 1 year postoperatively on Fletcher frequencies. An air-bone gap closure within 20 dB was achieved in 81% of all cases 1 year postoperatively. No cases of extrusion have been seen in our series. CONCLUSION: Our findings suggest that malleus allografts are capable of generating good and stable functional results as malleus-stapes assembly.     

Surgery for tympanosclerotic stapes fixation accompanied by malleus fixation at the anterior malleus: report of 2 cases

Most tympanosclerotic stapes fixation involves fixation or erosion of the malleus and/or incus. This status of the ossicular chain is one reason that ossiculoplasty for tympanosclerotic stapes fixation is more difficult than that for otosclerosis. In some cases, the malleus is fixed only at the anterior, while the incus is intact. In such cases, anterior spinotomy can recover mobilization of the malleus, then a prosthesis can be used for the long process of the incus during ossiculoplasty. We conducted stapedectomy with anterior spinotomy on 3 ears in 2 patients. Over 15 dB of hearing was regained in all 3 ears 6 months after surgery. No significant sensorineural hearing loss was seen in any ear. To adapt this surgical procedure, it is necessary to evaluate preoperative CT findings and the status of the ossicular chain during surgery.     

Success rate in revision stapes surgery for otosclerosis.

OBJECTIVE: The aim of this study was to evaluate the hearing results of revision stapes surgery performed because of previously failed operations and to determine the causes of failure. STUDY DESIGN: Retrospective review of revision stapes operations. SETTING: Tertiary referral center. PATIENTS: Sixty-three consecutive revision stapes operations were performed in 56 patients over a period of 12 years (1992-2004). The indication for revision surgery was recurrent or persistent air-bone gap greater than 20 dB after primary surgical treatment of otosclerosis of the oval window. RESULTS: All patients were operated on to improve hearing. Sixty-three revision stapes operations resulted in closure of the air-bone gap to 10 dB or less in 52.4% of cases. The average postoperative air-bone gap was 13.1 dB, and the mean pure-tone average improvement was 12.9 dB. In six patients (9.5%), revision surgery produced no change in hearing, and in four (6.3%) the hearing decreased by 5 dB or more. In one patient, the operation resulted in a profound hearing loss. Prosthesis malfunction was the most common primary cause of failure (60.3%). The original prosthesis was replaced with a new one in 48 cases. In 30 of these (62.5%), closure of the air-bone gap to within 10 dB was achieved. In 15 cases, the prosthesis was not replaced, and in only four of these (26.7%), closure of the air-bone gap within 10 dB was obtained (p < 0.022). CONCLUSION: Revision stapes surgery is less likely to be successful than the primary operation. Closure of the air-bone gap to within 10 dB was achieved in 52.4% of patients. The success rate was better in cases where the original prosthesis was replaced with a new one. The risk for decreased bone-conduction threshold does not seem to be higher than in primary surgery.     

Revision stapes surgery: the malleus to oval window wire-piston technique

OBJECTIVE: To determine the effectiveness of the malleus to oval window wire-piston revision stapes surgery technique. STUDY DESIGN: A retrospective analysis of 243 stapes procedures performed by the senior author over a 10-year period identified 15 revisions. Five patients underwent a malleus to oval window wire-piston technique. All patients were followed for at least 6 months. The surgical outcome including audiologic data and complications are noted. METHODS: Stapes surgery was performed on an ambulatory basis by way of a transcanal approach under local anesthesia with monitored sedation by the same surgeon using a laser technique and a stapes wire-piston prosthesis. RESULTS: Among revision stapes procedures, there was no significant difference in the air-bone gap closure or complication rate between the incus to oval window and the malleus to oval window techniques. The average preoperative air-bone gap in all revisions was 32 dB, whereas the mean postoperative gap was 10 dB hearing loss. CONCLUSIONS: In experienced hands, revision stapes surgery using the malleus to oval window stapes wire-piston prosthesis is safe and effective.     

Stapes surgery: the diameter of the long process of the incus.

HYPOTHESIS: The aim of this study was to examine the long process of the incus in respect of its shape and its dimensions at the site of the attachment of a stapes prosthesis. BACKGROUND: One of the complications in stapes surgery is the erosion of the long process of the incus at the site of the attachment of the prosthesis, resulting in a fluctuating conductive hearing loss. Knowing the dimensions of the attachment site of the prosthesis at the long process of the incus will make it possible to optimize the size of the prosthesis loop. METHODS: The incus was obtained from 11 patients who had undergone middle ear surgery for hearing improvement or cholesteatoma removal. The ossicles were kept in 4% paraformaldehyde and were processed for histological examination after decalcification in ethylenediamine tetra-acetic acid. The 5-microm slices were stained with toluidine blue and examined in the light microscope. Using digitized video images of the histological slices, the diameters, circumference, and surface of the specimens were determined. RESULTS: The diameter of the long process of the incus at 1.4+/-0.28 mm from the tip, which is the average site of prosthesis attachment, showed an oval shape with a minimum diameter of 0.66+/-0.05 mm, a maximum diameter of 0.81+/-0.1 mm, and a circumference of 2.46+/-0.23 mm. CONCLUSION: The loop of a stapes prosthesis should have the following dimensions: diameter 0.9 mm, loop length of 2.2 mm, and opening of loop 0.7 mm. However, the material of the prosthesis and its malleability are also important factors.     

Repair of the ossicular chain with an ionomer cement by an inadequate incus after prior stapes surgery for otosclerosis

Use of an ionomer bone cement is described for repairing the ossicular middle ear system in revision stapes surgery. The cement was used to enlarge an eroded inadequate incus to allow placement of a new stapes prosthesis. Reconstruction of the incus with this new bone cement was readily performed and hearing results after 2 years of follow-up have been promising.