Experience with stapedectomy in a developing country: a review of 200 cases

Since stapedectomy was first performed in 1956, many innovations have been described. We retrospectively analyzed 200 cases of stapedectomy that had been performed with standard otologic instruments. Of the 200 patients, 54 (27.0%) had significant sensory deafness associated with footplate fixation. In most cases, the footplate was partially removed (stapedotomy group); in the remainder, the footplate was removed in its entirety or subtotally (stapedectomy group). Of the 200 patients, 163 were available for short-term follow-up. The air-bone gap was closed to within 10 dB in roughly 83% of both groups. Although long-term follow-up was possible in only a limited number of cases, we believe that an experienced otologist working with standard equipment and a basic operating microscope can obtain satisfactory stapedectomy results with minimal complications.     

Reconstruction of the entire ossicular conduction mechanism

OBJECTIVES/HYPOTHESIS: Stapes fixation combined with fixation, absence, or malformation of the malleus-incus complex requires an uncommon surgical reconstruction and offers a unique combination of challenges and hazards. This situation may occur in the presence of severe tympanosclerosis, otosclerosis, congenital ossicular malformations, and revision surgery for either stapedectomy or chronic ear disease. In previous reports, this procedure has been grouped with total ossicular reconstruction without much distinction. However, the challenges unique to this problem deserve special consideration. The present report offers a treatment plan for a group of patients requiring reconstruction of the entire ossicular conduction mechanism including removal of the stapes footplate. STUDY DESIGN: Retrospective review. METHODS: Three thousand three hundred fifty (3350) charts of patients requiring total ossicular replacement prostheses (TORPs) were reviewed. Of this group of patients, only 21 of 3350 patients from 1977 to 1999 required TORP placement and removal of the stapes footplate. The patients were followed for an average period of 50 months. RESULTS: Hearing results indicated an overall improvement in the air-bone gap of 10 dB, with 52% achieving an air-bone gap of less than 20 dB. Of the 21 cases, 5 revision surgeries were performed. Three were performed because of a displaced TORP (14.2%). and 2 were performed because of extruded TORPs (9.5%). CONCLUSIONS: Reconstruction of the entire ossicular conduction mechanism including removal of the stapes footplate can be successfully achieved with improvement of the air-bone gap of less than 20 dB. Hearing results and extrusion rates are comparable to reported results of TORP placement on a mobile footplate. Successful stapedectomy and simultaneous ossicular chain reconstruction can be performed as a single or staged procedure. Special attention is paid to avoid intrusion of the prosthesis into the vestibule.     

Stapedotomy and anatomical variations of the facial nerve

Among the 595 stapedotomies performed between 1992 and 1999 (surgeon R. H?usler), there were 40 cases (6.7%) where the facial nerve had an abnormal course. In 32, a partial nerve prolapse over the oval window was noted with (6 cases, 1 being a duplicated nerve around the oval window) or without (26 cases) dehiscence in the long bony canal. In 8 cases, there was a total prolapse of the nerve over the oval window, with 2 special cases: facial nerve having an inferior course over the oval window and the promontory; facial nerve being widely spread over the oval window and the promontory. Concomitant anomalies of the stapes were seen and several patients had dysmorphic syndromes with conductive hearing loss since early childhood. Stapedotomy was performed in 39 patients. In the 32 cases of partial nerve prolapse, a small piston (0.4 mm) was placed in the lower part of the oval window which was sometimes enlarged towards the promontory, except when the nerve was duplicated: the prosthesis was placed into the footplate between the nerve branches. In the 8 patients with total facial nerve prolapse, the prosthesis was either placed directly in a burr hole into the promontory just below the oval window (6 cases), or, when the nerve ran over the promontory and over the oval window, the prosthesis was placed above the oval window at the site where the facial nerve is usually located (1 case). In the case where the nerve was spread widely over the oval window and the promontory, no prosthesis was placed. In the 39 patients where a stapedotomy was performed, the average hearing level gain ranged from -15 dB to 40 dB (average: 18 dB) at 0.5, 1, 2 and 4 kHz. The average residual air-bone gap was < 30 dB in 36 patients (92.3%), < 20 dB in 30 (77%) and < 10 dB in 16 (41%). A post-operative additional hearing loss > or = 10 dB occurred in 3 cases (10, 12.5 and 12.5 dB). There were no cases of post-operative deafness or facial palsy. This analysis shows that in many cases with an aberrant course of the facial nerve, stapedotomy using adequate and sometimes non-conventional techniques can give post-operative hearing improvement.     

Is it possible to predict diffuse obliterative otosclerosis preoperatively by audiologic examination

Patients with diffuse obliterative otosclerosis have more extensive footplate pathology than annular cases. As a result of this more skill is required for diffuse otosclerosis cases, and postoperative hearing results are usually worse than annular cases. In this retrospective study we compared the preoperative audiological features of annular and diffuse otosclerosis patients. The subjects were 60 patients with conductive hearing loss who had undergone stapedectomy. Annular and diffuse groups were comprised of 30 patients each. Annular otosclerosis was defined as the footplate pathology involving the annular ligament only, where the footplate of the stapes is very thin and retains its bluish color. On the other hand diffuse, obliterative otosclerosis was defined as the pathology involving the whole footplate and also in some cases extending beyond the confines of the annular ligament. In each group preoperative air- and bone-conduction levels at 125–6000 Hz and 500–4000 Hz were noted respectively. Average air-bone gap for the obliterative otosclerosis group was 37.5 dB; the same value for the annular group was 23.8 dB (p<0.05). The gap characteristics of the audiogram were different for the two groups. The annular group had an air-bone gap which was nearly constant for all the frequencies. In the diffuse otosclerosis group, the air-bone gap was more prominent in the low frequencies and it decreased at higher frequencies. No difference was noted in bone-conduction thresholds, and Carhart notch between the two groups. This study demonstrated that a large air-bone gap in patients with conductive hearing loss may be a sign of diffuse obliterative otosclerosis. This may warn the surgeon that a more challenging surgery is possible, and the patient may have a less favorable hearing result. Therefore, in the presence of a large air-bone gap, it may be appropriate to inform the patient of the strong possibility of diffuse otosclerosis.     

Is it possible to predict diffuse obliterative otosclerosis preoperatively by audiologic examination

Patients with diffuse obliterative otosclerosis have more extensive footplate pathology than annular cases. As a result of this more skill is required for diffuse otosclerosis cases, and postoperative hearing results are usually worse than annular cases. In this retrospective study we compared the preoperative audiological features of annular and diffuse otosclerosis patients. The subjects were 60 patients with conductive hearing loss who had undergone stapedectomy. Annular and diffuse groups were comprised of 30 patients each. Annular otosclerosis was defined as the footplate pathology involving the annular ligament only, where the footplate of the stapes is very thin and retains its bluish color. On the other hand diffuse, obliterative otosclerosis was defined as the pathology involving the whole footplate and also in some cases extending beyond the confines of the annular ligament. In each group preoperative air- and bone-conduction levels at 125-6000 Hz and 500-4000 Hz were noted respectively. Average air-bone gap for the obliterative otosclerosis group was 37.5 dB; the same value for the annular group was 23.8 dB (p<0.05). The gap characteristics of the audiogram were different for the two groups. The annular group had an air-bone gap which was nearly constant for all the frequencies. In the diffuse otosclerosis group, the air-bone gap was more prominent in the low frequencies and it decreased at higher frequencies. No difference was noted in bone-conduction thresholds, and Carhart notch between the two groups. This study demonstrated that a large air-bone gap in patients with conductive hearing loss may be a sign of diffuse obliterative otosclerosis. This may warn the surgeon that a more challenging surgery is possible, and the patient may have a less favorable hearing result. Therefore, in the presence of a large air-bone gap, it may be appropriate to inform the patient of the strong possibility of diffuse otosclerosis.     

Surgical treatment of chronic middle ear disease. 1. Myringoplasty and tympanoplasty

Results of myringoplasty or tympanoplasty were evaluated in 225 ears followed for at least one year after surgery. Repair of the tympanic membrane with an underlay connective tissue graft (fascia in 90%) was successful in 97% of the ears. One late perforation developed 3 years postoperatively. The average postoperative air-bone gap was 4.8 dB in 88 cases of myringoplasty, the series including three ears with a rigid footplate. Rigid incus and malleus should not be mobilized but subjected to resection and reconstruction. Poor tubal function caused adhesive changes in one ear (1%). In tympanoplasty the average postoperative air-bone gap was 11.3 dB in 100 ears with stapes present and 20.6 dB in 36 ears with only the footplate remaining. Of the 137 tympanoplasty ears, 10 (7%) showed prominent adhesive changes. In 36 ears with cholesteatoma there was one recurrence 3 years later (3%). An air-bone gap of less than 20 dB was postoperatively noted in 94% of the ears undergoing myringoplasty and in 69% of the ears undergoing tympanoplasty.     

Argon laser in difficult stapedotomy cases

Objective: The success and safety of argon lasers in stapedotomy surgery is now well documented. This study reviews results in problematic situations in which the argon laser may be of particular advantage to successful completion of the stapedotomy procedure. Study Design: Retrospective chart review. Methods: A retrospective review of the author's most recent 200 stapedotomy cases was performed, identifying 32 patients who at surgery were either found to have a prolapsed dehiscent facial nerve (three cases), developed a floating footplate (eight cases), or were undergoing a revision stapedotomy (21 cases). Four-frequency, pure-tone average air and bone conduction thresholds were computed before and after surgery. Success was defined as closure of the air-bone gap to within 10 dB, while an air-bone gap within 20 dB was considered improvement. Results: Successful closure of the air-bone gap was achieved in all eight patients with a mobilized footplate, in all three patients with a prolapsed dehiscent facial nerve, and in 43% of the patients undergoing a revision stapedotomy. The rate of improved air-bone gap in the revision cases was 62%. In one revision stapedotomy patient a decrease in speech discrimination occurred. Otherwise, there were no cases of sensorineural hearing loss. Neither intraoperative nor postoperative dizziness was reported by any patient, and all were discharged on an outpatient basis. Conclusion: The argon laser was found to be safe, effective, and a valuable adjunct for the difficult stapedotomy cases when unexpected obstacles such as a prolapsed dehiscent facial nerve or a mobilized footplate are encountered, as well as for the planned, more difficult revision cases. Laryngoscope, 108:1669-1673, 1998     

Diode laser in otosclerosis surgery: first clinical results.

OBJECTIVE: To evaluate the functional results of otosclerosis surgery using diode laser. STUDY DESIGN: Retrospective cohort analysis. PATIENTS: One hundred seven patients operated on for otosclerosis with a diode laser (119 ears, all primary cases) and 141 patients operated on with a conventional technique (141 ears, all primary cases). Revision cases using the diode laser were also described. METHODS: Preoperative tomographic computed scan findings and intraoperative observations were collected. Pure-tone and vocal audiometry was performed preoperatively and postoperatively (at 3 mo and 1 yr). RESULTS: In the laser group, the air-bone gap was 29 +/- 0.8 dB (n= 112) preoperatively and 9 +/- 0.6 dB (n = 58) at 1 year. Air conduction was improved by 22 +/- 1.7 dB at 1 year (n = 58). In the conventional group, the air-bone gap was 32 +/- 0.9 dB (n=127) preoperatively and 10 +/- 0.6 dB (n = 127) at 1 year. Air conduction was improved by 25 +/- 1.1 dB (n = 127) at 1 year. No difference of hearing gain was observed between the 2 groups at 1 year. A decreased rate of footplate fracture was observed with the diode laser (3.6%) compared with the conventional technique (21.3%). CONCLUSION: Diode laser is a reliable and safe device for otosclerosis surgery. The functional results were similar to those reported in other series.     

Homograft microlathed femur prosthesis in stapedectomy

The use of homografts in ossiculoplasty has been well documented in the literature. In the early 1980s, nonossicular homograft otic capsule bone was used as a prosthetic material in stapedectomy. We began using homograft femur as a prosthetic material in the early 1990s. In this article, we report the results of a retrospective study of the use of homograft femur prostheses. A series of 300 stapedectomies was performed between Aug. 24, 1992, and Jan. 20, 2000. Total footplate removal with preservation of the posterior crus was our procedure of choice. However, in 116 of these cases, the posterior crus could not be used, and a homograft femur prosthesis was substituted. For these prostheses, all homograft femurs were obtained from the American Red Cross. All prostheses were prepared in the bone laboratory and stored in the bone bank until needed. After an adequate period of follow-up, we tabulated our results. We found that in 89 of 113 cases (78.8%) available for follow-up, the air-bone gap was completely closed. In addition, the air-bone gap was closed to within 5 dB in 11 patients (9.7%) and closed to within 10 dB in five patients (4.4%). In all, 105 of the 113 homograft femur prosthetic procedures (92.9%) resulted in a successful outcome.     

Short- and long-term results of stapedotomy and stapedectomy with a teflon-wire piston prosthesis

We analyzed the results of 604 cases of primary stapes surgery performed between 1974 and 1997 with replacement of the stapes by a 0.6- or 0.8-mm Schuknecht Teflon-wire piston. At long-term follow-up (1 to 21 years; mean, 7 years), the residual air-bone gap was 10 dB or less in 79% of the cases. The hearing results and postoperative complications were comparable to those reported by authors who used the same evaluation criteria. Although the aim of the surgery was to perform a small stapedotomy with a narrow footplate perforation (0.8 mm), a large stapedotomy or a stapedectomy was performed in 134 cases (22.2%) because of surgical or anatomic conditions. Our results show that the larger footplate perforations allowed a better correction of the air-bone gap at the lower frequencies. The ears with larger perforations did not show a higher incidence of sensorineural hearing loss.     

Endoscopic stapedotomy: our view point

Use of endoscope in middle ear surgery is not new, yet there is resistance to its use in stapedotomy. This is due to perceived long learning curve in shifting from conventional microscope to the endoscope and fear of one-handed work. (1) to present a case series of endoscopic stapedotomies and analyze the operative findings. (2) Discuss the merits and demerits of same. 20 patients with otosclerosis underwent stapedotomy over 5 years using 0°, 4 mm nasal endoscope of 18 cm length. Visualization of middle ear structures, surgical steps, operative time, hearing results and complications were analyzed. In all 20 cases, (13 males, 7 females, age: 32.7 years) manipulation of endoscope within the canal was easy facilitating endomeatal incision and elevation of tympanomeatal flap. An optimum exposure of incudo-stapedial joint was obtained in 88.24 % cases. Adequate exposure of crura was obtained in 82.35 % and the footplate in 95 %. The removal of postero-superior bony wall was required in 30 % and chorda tympani mobilization in 25 % of cases. The average operative time was 31 min. Audiometry done at 6 weeks showed, complete air–bone gap closure in 55 %, mild conductive hearing loss (up to 20 dB) in 30 % and mixed hearing loss in 2 cases (BC up to 30 dB and air–bone gap up to 20 dB). In one patient who initially had hearing improvement post operatively, developed moderate conductive hearing loss at 10 weeks. Performing fully endoscopic stapedotomy using a 4 mm nasal endoscope is a feasible option giving excellent visualization with good results.     

A new L-shaped titanium prosthesis for total reconstruction of the ossicular chain.

OBJECTIVE: To describe the technique used for total ossiculoplasty with the Fisch titanium total prosthesis and evaluate the 1-year postoperative functional results in patients presenting with the stapes (or footplate) without the malleus handle. STUDY DESIGN: Prospective trial with preoperative and postoperative comparison. SETTING: Academic and private practice tertiary care center for otologic surgery. PATIENTS: Forty-nine consecutive patients operated on from September 1996 to December 2000. SURGERY:: Staged ossicular reconstruction with a Fisch titanium total prosthesis placed between the footplate and the tympanic membrane without regard to the presence or absence of the stapes arch. Coupling of the prosthesis to the footplate was achieved by various techniques, including perforation, foot and spike on the footplate without perforation, and shaft alone (without foot) with tragal cartilage fixation (disc or small wedges). There was no interposition of cartilage between the prosthesis head and the tympanic membrane. MAIN OUTCOME MEASURES: Pre- and postoperative air and bone-conduction thresholds and air-bone gaps for pure-tone averages of three and four frequencies and for single frequencies. RESULTS: Postoperative air-bone gap closures within 20 dB distributed equally (50%) between 0.5, 1, and 4 kHz and reached the highest rate (89%) at 2 kHz (p < 0.05). The postoperative air-bone gaps for pure-tone averages reached 0 to 20 dB in 57% and 0 to 30 dB in 87% of the cases. There were no dead ears and no partial or total extrusions of prostheses. The best functional results were achieved through perforation coupling of the spiked foot to the footplate in large oval windows and after fixation of the shaft (without foot) with tragal cartilage disc in narrow oval windows. CONCLUSION: The functional results of the L-shaped Fisch titanium total prosthesis implanted in ears with the stapes but no malleus handle are best at 2 kHz and better than those of comparable columellar titanium prostheses over the remaining tested frequencies.     

Revision surgery for otosclerosis

The outcome of surgery was analyzed in 76 otosclerosis patients (82 operations) undergoing revisions during the period 1986-89. The ears were divided into 3 groups based on preoperative A-B gaps 1) larger than 25 dB, 2) between 10 to 25 dB, and 3) less than 10 dB. A final hearing gain of more than 11 dB was recorded in 76%, 40% and 10% of the ears in groups 1, 2 and 3, respectively. In the groups with conductive component none of the ears deteriorated. In the sensorineural group 2 patients suffered further loss of 10 and 29 dB, respectively, and one ear became deaf. At revision the most common causes of conductive impairment were found to be dislocation of the prosthesis, remnants of footplate or new bone growth. Fistula was suspected in 10 ears and verified in 5. Several reconstruction methods must be mastered.     

胆脂瘤型和骨疡型中耳炎Ⅰ期鼓室成形术的疗效观察

目的：探讨胆脂瘤型和骨疡型中耳炎Ⅰ期鼓室成形术的可行性及疗效影响因素。方法：52例(52耳)慢性化脓性中耳炎(胆脂瘤型30耳，骨疡型22耳)患者在清除病变的同时行鼓室成形术，其中单纯鼓室成形术12耳，乳突根治加鼓室成形术40耳。结果：全部病例均干耳，无一例胆脂瘤复发。语频段听力提高30dB以上者5耳，提高20～29dB者9耳，提高10～19dB者31耳，小于10dB者7耳，无听力下降者。结论：胆脂瘤型和骨疡型中耳炎可行Ⅰ期鼓室成形术，鼓膜有效振动面积、镫骨及镫骨底板的活动度是影响听力的重要因素，咽鼓管功能不良是手术失败的主要原因。     

Surgical treatment of tympanosclerosis

OBJECTIVE: To report the hearing results of the surgical treatment of tympanosclerosis. STUDY DESIGN: A retrospective review of surgically treated cases of tympanosclerosis. SETTING: A tertiary referral center. PATIENTS: One hundred fifteen patients with middle ear tympanosclerosis operated on between 1987 and 1996, with an average age of 36 years (range 18-59 years). Cases were classified into four groups according to Wielinga and Kerr. Those with an associated cholesteatoma were excluded. INTERVENTION: Depending on the ossicular status, either mobilization of the major ossicles or epitympanic bypass procedure, mobilization of the stapes or stapedectomy. MAIN OUTCOME MEASURES: The postoperative pure-tone average was compared with the preoperative levels by use of conventional audiometry. The air-bone gap was measured. RESULTS: The average postoperative air-bone gap was 18.0+/-10.21 dB in the type II group (attic fixation of the malleus-incus complex with a mobile stapes). 21.8+/-9.5 dB in the type III group (mobile malleus-incus complex, if present, with stapes footplate fixation), and 22.92+/-10.03 dB in the type IV group (fixation of both the stapes footplate and the malleus-incus complex). Patients with a fixed malleus and mobile stapes had significantly better hearing results than those with stapes fixation (p = 0.042, Mann-Whitney U test). CONCLUSION: In ossicular attic fixation, atticotomy and mobilization of ossicles yielded better results than did the epitympanic bypass procedure. The difference, however, did not reach statistical significance. Patients with fixed stapes treated with stapedectomy displayed good hearing results immediately after surgery, but the air-bone gap deteriorated after some time.     

Studies on the mechanics of the normal human middle ear

The middle ear was studied in temporal bone preparations using a laser-Doppler interferometer. For measurements at a sound level of 80 dB SPL this method proved to be very reliable, as was shown by good reproducibility of results in experiments over more than 6 hours. The vibrations of the tympanic membrane and stapes footplate were studied from 200 Hz to 10 KHz and the results demonstrate a piston-like movement of the stapes footplate up to 120 dB SPL. The damping effect of the normal ear is located mainly at the footplate/cochlea level and the middle ear cavity per se does not contribute significantly to the stiffness of the middle ear system.     

晚期耳硬化症的治疗效果

目的探讨镫骨手术对晚期耳硬化症的治疗效果。方法随机抽取300例1970年至1999年间的耳硬化症手术病例，对符合晚期耳硬化症标准[500—2000Hz骨导听阈（听力级，下同）均值≥40dB，气导听阈均值≥70dB的混合性聋]的68例（77耳）进行回顾性分析。结果68例（77耳）术后，500—2000Hz纯音平均听阈：气导（听力级，下同）由术前的77．32dB减至53．70dB，提高23．62dB；71耳（92．21％）气导提高≥10dB，其中46耳（59．74％）气骨导差闭合。500～4000Hz纯音平均听阈：气导由79.01dB减至58．23dB，提高20。78dB；68耳（88．31％）气导提高≥10dB，其中32耳（41．56％）气骨导差≤10dB（闭合）。随访5～25年，听力稳定的有67耳，听力下降4耳（均为镫骨提高术患者，再次手术后听力均有提高），听力较术后进一步提高的有28耳。结论镫骨手术是治疗耳硬化症的有效手段，也是治疗晚期耳硬化症或极晚期耳硬化症的有效方法之一。镫骨手术对改善晚期耳硬化症或极晚期耳硬化症患者的听力有较大帮助。     

Ossiculoplasty with intact stapes and absent malleus: the silastic banding technique.

OBJECTIVE: To report an original method of ossicular reconstruction with intact stapes and absent malleus. Ossiculoplasty is performed with a total ossicular replacement prosthesis positioned from the stapes footplate to the under-surface of the tympanic membrane, using a Silastic banding technique to stabilize the prosthesis. STUDY DESIGN: A prospective study of ossicular reconstruction using the Silastic banding technique. A consecutive series of cases with intact stapes superstructure and missing malleus handle (Austin-Kartush Group C) is presented. SETTING: One tertiary referral center. PATIENTS: Ninety-nine patients who underwent total ossicular reconstruction with Silastic banding technique were enrolled in the study from January 2000 to December 2002. INTERVENTIONS: Ossiculoplasty with total ossicular replacement prostheses with Silastic Rubber Band for chronic otitis media and non-inflammatory disease. MAIN OUTCOME MEASURES: Preoperative and postoperative audiometric evaluation using conventional audiometry. Air-bone gap, bone-conduction threshold, and air-conduction threshold were assessed. Postoperative audiometry was performed at the 6th, 9th, 12th, 18th, 24th, and 36th months. RESULTS: Overall, a postoperative air-bone gap closed to within 10 dB was achieved in 61.5% of cases. An air-bone gap smaller than 20 dB was obtained in 77% of cases. Postoperative improvement of air-conduction thresholds by at least 20 dB was found in 51% of cases. There was no case of postoperative sensorineural hearing loss. One case of extrusion of the prosthesis was seen (1%). CONCLUSION: Stabilizing the total ossicular replacement prosthesis with the Silastic banding technique when performing ossicular reconstruction is a safe, effective method when the stapes supra-structure is present and the malleus absent.     

Three-dimensional stapes footplate motion in human temporal bones

The literature provides conflicting information on whether the motion of the stapes footplate is piston-like or some other type of motion, such as rotational or rocking. Examination of the three-dimensional (3D) motion of the stapes footplate appears to be an excellent way to understand this complicated motion. Five microsphere reflective targets were placed on the stapes footplate in ten fresh human cadaver temporal bone preparations, and their vibration measured through an extended facial recess approach using a laser Doppler vibrometer. The five target sites on the stapes footplate were center, anterior, posterior, superior and inferior. The stimulus was a sound input of 80-120 dB SPL at the tympanic membrane over a frequency range of 0.1 to 10 kHz. The 3D motion of the stapes footplate was calculated using the velocity amplitude and phase obtained for each target. For frequencies up to 1.0 kHz the vibration of the stapes footplate was primarily piston-like; this motion became complex at higher frequencies, with rotary motion along both the long and short axis of the footplate. When the cochlea was drained, stapes footplate motion became essentially piston-like for all frequencies.     

CO2激光辅助人工镫骨技术治疗耳硬化24例报告

目的：应用CO2激光辅助Ugo Fisch人工镫骨技术治疗耳硬化并观察其疗效。方法：技术关键：①首先解离砧镫关节；②根据面神经水平段与镫骨上结构之间的间隙大小选用0．3或0．4mm的人工镫骨；③在镫骨底板开窗，安装人工镫骨后处理镫骨上结构及镫骨肌腱；④以CO2激光行镫骨底板开窗、处理镫骨肌腱及镫骨上结构。结果：术后言语频率气骨导差≤15dB者23例，占95．8％；言语频率气骨导差≤10dB者21例，占87、5％，平均8．5dB；术后反应轻微，无恶心、呕吐及明显眩晕，22例患者术后即刻可下床走动。结论：CO2激光辅助Ugo Fisch人工镫骨技术是治疗耳硬化的可靠技术，疗效显著、安全系数高、术后反应轻微是其突出的优点。