Clinical results after stapedotomy: a comparison between the erbium: yttrium-aluminum-garnet laser and the conventional technique.

OBJECTIVE: The objective of this study was to assess whether the use of the erbium: yttrium-aluminum-garnet (Er:YAG) laser has negative effects on inner ear function and to compare the short- and long-term hearing outcome of patients undergoing conventional stapedotomy versus laser stapedotomy. STUDY DESIGN: Retrospective review of prospectively collected audiometric data of patients with otosclerosis operated on by one experienced surgeon. SETTING: Academic tertiary referral center. PATIENTS: A total of 266 stapes surgeries were evaluated for intraoperative findings, of which 209 patients were evaluated for preoperative and postoperative hearing thresholds after a 6- to 452-week (mean, 22 wk) audiological follow-up. INTERVENTION: One hundred fifteen (43%) of the operations were performed conventionally, using manual perforators for stapedotomy (Group A); in 115 (43%) surgeries, the perforators were used in combination with the Er:YAG laser (Group B), and in 36 (14%) operations, the Er:YAG was used exclusively for footplate perforation (Group C). MAIN OUTCOME MEASURES: Pure-tone audiometry was performed before surgery, 2 days postoperatively (bone conduction only) and at 5, 26, and 57 weeks postoperatively. RESULTS: A postoperative temporary threshold shift of the bone conduction could be found in all groups. In Group C, where the laser was used exclusively for footplate perforation, this threshold shift was not only the most significant, but also-in contrast to the other groups-not totally reversible. In all techniques, a satisfactory air-bone gap closure could be achieved. The best long-term results (96% of the patients had 相似文献   

Prospective clinical study on cochlear function after erbium:yttrium-aluminum-garnet laser stapedotomy

OBJECTIVE: To assess whether the application of the emitting erbium:yttrium-aluminum-garnet (Er:YAG) laser in stapedotomy has negative effects on vestibular and cochlear functions. DESIGN: Prospective, with 12 to 14 months follow-up. SETTING: Academic tertiary referral center. PATIENTS: Twenty-four patients undergoing stapedotomy (primary surgery) in otosclerosis. INTERVENTION: All patients underwent Er:YAG laser-assisted stapedotomy for otosclerosis between January 2000 and June 2002. MAIN OUTCOME MEASURES: Early (1-3 days after surgery) and late (12-14 months after surgery) postoperative bone-conduction thresholds and the presence of post-operative tinnitus and vertigo were analyzed. In addition, the relation between applied laser energy and postoperative bone-conduction thresholds was calculated. RESULTS: In 22 patients, unchanged preoperative minus early postoperative pure-tone bone-conduction averages at 1, 2, and 4 kHz were observed. In one patient, a slight early deterioration between 10 and 20 dB was seen. In 18 patients, unchanged preoperative minus late postoperative pure-tone bone-conduction averages at 1, 2, and 4 kHz were observed. In two patients, a slight late deterioration between 10 and 20 dB was seen. In two patients, a new postoperative tinnitus was observed. No patient suffered from vertigo at the time of second evaluation. No correlation between applied laser energy and both postoperative bone-conduction thresholds was found. CONCLUSIONS: The Er:YAG laser stapedotomy in otosclerosis is a safe technique. Vestibular and cochlear function is not significantly disturbed after Er:YAG laser stapedotomy.     

Small fenestra stapedotomies with and without KTP laser: a comparison

The results of 33 small fenestra stapedotomies performed using conventional techniques were compared with the results of 33 stapedotomies performed using the argon or KTP laser. The ossicular chain was reconstructed using a Teflon wire piston of 0.6 mm diameter, and follow-up was at least 1 year. Over-closure of the air-bone gap or closure to within 10 dB was accomplished in 91% of the laser-treated group versus 72% of the conventionally treated group (p less than 0.10). The hearing results were statistically better in the laser group (p less than 0.05). Transient delayed vestibular symptoms, lasting from 1 to 3 weeks, were present in 39% of the laser-treated group and in 12% of the patients treated by conventional techniques (p less than 0.05). The KTP laser stapedotomy, using a micromanipulator mounted on the microscope, is a safe, efficient technique that reduces some of the technical difficulties associated with conventional stapes surgery. The main advantage of the laser is that it enables the surgeon to make an atraumatic, bloodless opening in a fixed or mobile stapes footplate without mechanical manipulation of the stapes. Using a lower wattage to vaporize the footplate and waiting several seconds between laser bursts may decrease the incidence of postoperative vestibular symptoms. The use of the KTP laser in stapes surgery represents a major advance in surgery for otosclerosis.     

The influence of Er. YAG laser application in fenestration to the inner ear

OBJECTIVE: Erbium (Er.) YAG laser may be usable for middle ear surgery because of its ability to ablate bony tissue. We investigated the inner ear damage caused by the fenestration to the inner ear with Er. YAG laser. DESIGN: We investigated the influence of Er. YAG laser on the inner ear using electrophysiological technique. RESULTS: Several cases had a decrease in endocochlear potential (EP) and cochlear microphonics (CM) after the fenestration to the inner ear. CONCLUSIONS: Er. YAG laser is safe if it is used for the small and superficial fenestration to the stapes footplate. However, a few extra pulses after fenestration are dangerous.     

Use of Er,Cr:YSGG versus standard lasers in laser assisted uvulopalatoplasty for treatment of snoring

Objectives: The aim of this study was to compare the effectiveness of the Er,Cr:YSGG (Waterlase) laser with KTP and CO₂ lasers in laser assisted uvulopalatoplasty (LAUP) for treatment of snoring. Study Design: This is a prospective study of 63 patients who were treated for snoring by LAUP either with Er,Cr:YSGG (n = 21) or with KTP (n = 21) or CO₂ lasers (n = 21). Histologic analysis was performed, and the effects of KTP and Waterlase on soft tissue were compared. Methods: Patients were examined by an ENT surgeon and tested with polysomnography. Probands who suffered from obstructive sleep apnea or had an apnea‐hypopnea index of 15 or greater were excluded from the study. The remaining patients were assigned to either Er,Cr:YSGG, KTP, or CO₂ laser therapy. The three lasers were compared from a postoperative recovery point of view by immunohistochemical examination. Results: Pain medications were used on average for 4.1, 6.5, and 10.1 days, and the times to return to normal diet were on average 4.5, 6.8, and 8.6 days in the Er,Cr:YSGG, KTP, and CO₂ groups, respectively. Two cases of bleeding were observed in the CO₂ group. Foreign body sensation occurred in 14%, 19%, and 19% of subjects in the Er,Cr:YSGG, KTP, and CO₂ groups, respectively. Velopharyngeal insufficiency was noticed in one KTP treated patient; however, it was transient. Snoring and apnea‐hypopnea index was significantly reduced in all groups. Significantly larger coagulation of soft tissue was found in the KTP group than in the Waterlase group. Conclusions: Patients treated with Waterlase recovered more quickly in comparison with patients in the KTP and CO₂ groups, which was confirmed by immunohistochemical findings. The laser techniques did not differ in effectiveness.     

��One-shot�� CO2 versus Er:YAG laser stapedotomy: is the outcome the same?

To assess and compare the functional results obtained by means of multiple-shot Erbium: yttrium?Caluminum?Cgarnet (Er:YAG) laser to those obtained using ??one-shot?? CO₂ laser stapedotomy in patients affected by otosclerosis. A retrospective case review was performed. Of the total number of 123 patients (114 ears) who underwent primary small-fenestra stapedotomy from January 2006 to September 2008, seven patients who received multiple-shot laser CO₂ stapedotomy were excluded from the study. The remaining 116 patients (104 ears) were sorted, and ??one-shot?? CO₂ laser stapedotomy (group A) was performed in 35/104 and Er:YAG laser stapedotomy (group B) in 69/104. After surgery, air conduction-pure tone average (AC-PTA) and air-bone gap (ABG) improved significantly in both groups, whereas sensorineural hearing loss (SNHL) and bone conduction (BC)-PTA did not change in both the groups. In group A, the postoperative ABG was significantly better (12.63 vs. 14.86?dB). Moreover, after ??one-shot?? stapedotomy, the AC-PTA significantly improved in all tested frequencies. On the contrary, in group B the AC-PTA improved significantly only in two frequencies (0.5 and 1?kHz). Consistent with previous reports, our findings confirm that laser stapedotomy is a safe and effective surgery, regardless of the technique. Based on our functional results, the ??one-shot?? CO₂ laser technique seems to be associated with a significantly better postoperative ABG if compared to Er:YAG laser stapedotomy.     

Cochlear protection and surgical precision in stapedotomy with Er:YAG laser

BACKGROUND: Using laser in stapedotomy has attracted a lot of attention since the nineties. It aims at minimizing complications due to hand-operated equipment, especially inner ear lesions, and achieving higher precision. We analyzed the clinical effect of Er:YAG laser with the question whether the postulated cochlea protection and foot plate perforation, optimized for better sound conduction, are achieved, compared to conventional stapedotomy. PATIENTS AND METHODS: We evaluated retrospectively audiometrical data including pre- and postoperative bone and air conduction thresholds of 114 consecutive patients, on whom we had performed stapedotomy and had inserted platinum-teflon prostheses. The intervention was done conventionally in 72 cases and in 42 cases with Er:YAG laser. RESULTS: In the lower and middle frequencies, laser technique resulted in a more pronounced improvement of bone conduction thresholds compared to conventional stapedotomy. The improvement of air conduction was more distinct in ears after laser surgery; also, the difference between air and bone conduction was reduced at a higher degree. CONCLUSION: Er:YAG laser in stapedotomy is coupled with cochlea protection, as demonstrated under clinical conditions, and allows higher hearing benefit of air conduction compared to conventional stapedotomy. Our results emphasize the impact of innovative laser technique on stapedotomy.     

Laser stapedotomy.

Thirty-four ears with conductive hearing loss due to otosclerosis were operated upon using the laser stapedotomy technique. Audiological results were compared with the results of 316 non-laser stapedotomies. The post-operative air-bone gap, calculated as the difference between the post-operative air and bone conduction levels, was smaller with the laser stapedotomy group. Also, the bone conduction showed significant improvement with the use of laser. Significant sensorineural hearing loss was not found in any of the laser-treated patients. According to our results, we concluded that laser is of benefit in stapes surgery for improving the hearing results and minimizing the inner ear trauma.     

Bilateral stapedotomy in patients with otosclerosis: a disability-orientated evaluation of the benefit of second ear surgery

This study reports the evaluation of the results of 80 stapedotomies in patients with bilateral otosclerosis. All pre- and postoperative audiological data, together with all relevant information of the operations, were stored in a database and analysed retrospectively. A new approach has been developed in order to evaluate the benefit of second ear stapes surgery in a more disability-orientated way using the AMA-criteria in the Guides to the Evaluation of Permanent Impairment. In all patients the percentage of Binaural Hearing Impairment (BHI) and the percentage of Impairment of the Whole Person (IWP) were determined according to the AMA-criteria. In patients who had both operations at the Academic Medical Centre it was found after the first operation that there was an important decrease in the BHI-percentage (from 26% to 10%) as well as for the IWP-percentage (from 9% to 4%). In addition, the percentages dropped significantly after the second operation (from 11% to 7% and from 4% to 2%, respectively). During follow-up there were no serious complications. It is concluded that bilateral stapedotomy is a safe procedure with good results.     

Hearing outcome following laser-assisted stapes surgery

This article reports the postoperative results of 76 operations addressing otosclerosis. All procedures were performed by the same surgeon and took place within a 4-year period. We compared the postoperative audiometric results of 54 laser-assisted procedures with those of 22 nonlaser operations. Our findings revealed a statistically significant improvement in the air-bone gap closure of the laser-operated patients: the air-bone gap was narrowed to within 10 dB in 72% of laser-operated cases versus 54% in nonlaser cases. Furthermore, laser use does not induce high-frequency sensorineural hearing loss. We believe that a laser entails less risk of inner ear microtrauma and improves the accuracy and reliability of stapedotomy.     

Comparison of argon and CO2 laser stapedotomy in primary otosclerosis surgery

PURPOSE: The primary use for the laser in otosclerosis surgery is to create a stapes footplate fenestration that obviates the need for mechanical footplate removal. Experimental studies that evaluate the potential safety of visible (argon and potassium-titanyl-phosphate [KTP]) and invisible (CO2) light laser systems in stapes surgery report conflicting results. The purpose of this study is to compare the clinical safety and efficacy of the CO2 and argon laser systems when used for primary laser stapedotomy. MATERIALS AND METHODS: A retrospective case review of 124 primary laser stapedotomies using either the argon (n = 59) or CO2 (n = 65) laser was performed. Data consisted of pre- and postoperative air and bone conduction audiometry, speech discrimination scores (SDS), intraoperative findings, and postoperative complications. Between group differences (argon v CO2) were sought using standard statistical methodology. RESULTS: The argon and CO2 laser groups were comparable with regards to age, sex, preoperative air-bone gap, and laterality. Mean preoperative air and bone conduction pure-tone average (PTA) and SDS were somewhat higher in the CO2 laser group (P < .05). Postoperatively, both groups showed similar results in mean change in air conduction PTA, air-bone gap, and SDS, as well as in the frequency of complications. There were no anacoustic ears in either group. CONCLUSIONS: The results suggest that the argon and CO2 laser systems are comparable with regards to safety and efficacy when used by experienced surgeons for stapedotomy.     

Use of a microsecond Er:YAG laser in laryngeal surgery reduces collateral thermal injury in comparison to superpulsed CO2 laser

Despite causing significant thermocoagulative insult, use of the carbon dioxide (CO₂) laser is considered gold standard in surgery for early stage larynx carcinoma. Limited attention has been paid to the use of the erbium:yttrium–aluminium-garnet (Er:YAG) laser in laryngeal surgery as a means to reduce thermal tissue injury. The objective of this study is to compare the extent of thermal injury and precision of vocal fold incisions made using microsecond Er:YAG and superpulsed CO₂ lasers. In the optics laboratory ex vivo porcine vocal folds were incised using Er:YAG and CO₂ lasers. Lateral epithelial and subepithelial thermal damage zones and cutting gap widths were histologically determined. Environmental scanning electron microscopy (ESEM) images were examined for signs of carbonization. Temperature rise during Er:YAG laser incisions was determined using infrared thermography (IRT). In comparison to the CO₂ laser, Er:YAG laser incisions showed significantly decreased epithelial (236.44 μm) and subepithelial (72.91 μm) damage zones (p < 0.001). Cutting gaps were significantly narrower for CO₂ (878.72 μm) compared to Er:YAG (1090.78 μm; p = 0.027) laser. ESEM revealed intact collagen fibres along Er:YAG laser cutting edges without obvious carbonization, in comparison to diffuse carbonization and tissue melting seen for CO₂ laser incisions. IRT demonstrated absolute temperature rise below 70 °C for Er:YAG laser incisions. This study has demonstrated significantly reduced lateral thermal damage zones with wider basal cutting gaps for vocal fold incisions made using Er:YAG laser in comparison to those made using CO₂ laser.     

Thermal Effects of Laser Stapedectomy in an Animal Model: CO2 Versus KTP

Although use of the laser for stapedectomy has become common in recent years, controversy remains regarding whether the CO₂ or visible-spectrum lasers (argon and KTP) are best suited for this operation. The main concern has been the potential for thermal injury to the inner ear with the visiblespectrum lasers attributable to their absorption characteristics. To further investigate this issue, the author performed 20 laser stapedectomies on adult chinchillas. Following placement of a 0.127-mm-diameter copper/constantan thermocouple (sampling at 12 Hz) beneath the footplate on the medial wall of the vestibule via a distant fenestration site, thermal changes with a micromanipulator-based CO₂ and fiberoptic KTP system were compared. This was the first live animal model comparison of these two lasers. There was no statistical difference in the mean temperature elevation between the two systems ( P = 0.395).     

The argon laser in surgery for chronic ear disease and otosclerosis

The use of the argon laser in chronic ear disease and otosclerosis surgery is reviewed. Its advantages and limitations are discussed, and safe parameters for use established. The argon laser is an effective tool to remove, cut, and coagulate tissue. It was used in over 500 microsurgical otologic procedures without deleterious effects. One hundred primary laser stapedotomies were performed, and the audiological results were compared to those obtained using conventional small fenestra stapedectomy techniques. No significant statistical difference was present in the audiologic results after 1 year of observation. The clinical course of the laser stapedotomy patients suggested this technique was less traumatic than conventional techniques.     

Functional results of 394 bilateral stapedotomies evaluated with the Glasgow Benefit Plot

This study aimed to evaluate the results of 394 bilateral stapedotomies according to the American Academy of Otolaryngology–Head and Neck Surgery (AAO–HNS) guidelines and with the Glasgow Benefit Plot (GBP) and also analyze the benefit of a second-ear stapedotomy in achievement of normal and symmetrical hearing using retrospective chart review. The charts of 1,369 stapedotomies performed by senior author (J.H.) from 1991 to 2006 were reviewed. Results of 394 bilateral stapedotomies were included. The hearing results were evaluated according to the 1995 AAO–HNS Committee on Hearing and Equilibrium (CHE) guidelines and the GBP criteria. Success rates after the first and second ear surgeries were separately analysed. ABG closure ≤20 dB was demonstrated in 98% of cases after both first and second procedures. Postoperative AC gain was higher in the first ear surgery compared with the second ear surgery in all groups of preoperative hearing impairment. As a result of first ear surgery, 142 (72%) patients changed into the category of unilateral hearing loss. As a result of second ear surgery, 125 (64%) patients changed into the category of normal and symmetric hearing. In this study the largest group of 394 primary bilateral stapedotomies was simultaneously evaluated according to AAO–HNS guidelines and GBP criteria. The results showed that the first ear surgery was more successful in achievement of normal hearing in the operated ear. Second ear surgery was more beneficial in providing symmetric hearing.     

Influence of pulsed laser irradiation on the morphology and function of the guinea pig cochlea

Recent experimental and clinical studies have demonstrated that several pulsed laser systems are also suitable for stapedotomy. The aim of the study was to investigate morphological and functional inner ear changes after irradiating the basal turn of the guinea pig cochlea with two pulsed laser systems of different wavelengths. The Er:YSGG (lambda=2.78 mcm) and Ho:YAG (lambda=2.1 mcm) lasers were used applying the laser energies necessary for perforating a human stapes footplate. The cochleas were removed 90 min, 1 day, 2 weeks, or 4 weeks after laser application. Acoustic evoked potentials (compound action potentials) were measured before and after laser application and at the above times immediately before removal of the cochleas. The organ of Corti was examined by scanning electron microscopy. Application of Er:YSGG laser parameters effective for stapedotomy had no adverse effects on Corti's organ in the guinea pig cochlea. On the other hand, effective Ho:YAG laser parameters cause damage to the outer hair cells with fusion of stereocilia and formation of giant cilia leading to partial or total cell loss. The inner hair cells and supporting cells were usually normal. These morphological data show a good correlation with the electrophysiological measurements. Our results clearly demonstrate that, besides achieving efficient bone management, the Er:YSGG laser has high application safety. On the other hand, the Ho:YAG laser is not well tolerated in our animal study. Its use in stapedotomy would be unreliable and dangerous for the inner ear.     

Experimentelle und klinische Erfahrungen mit dem Er:YAG-Laserotoskop

BACKGROUND AND OBJECTIVE: Laserotoscopes are suitable for low-pain outpatient surgery of otitis media with effusion (OME) under topical anesthesia. The myringotomy perforations should have a diameter greater than 2 mm to ventilate the middle ear for approximately 3 weeks. PATIENTS/METHODS: In this study, the clinical applicability of a prototype of an Er:YAG laserotoscope (Baasel Lasertechnik, Starnberg, Germany) was tested. Formalin-fixed human tympanic membranes yielded the parameters suitable for clinical application of an Er:YAG laserotoscope in patients. With a focussed laser beam (beam diameter 500 microns), one is able to achieve perforations of 50-micron diameter with one single laser pulse applying pulse energies of 70 mJ (energy density 36 J/cm2). The ablation rate, i.e., the tissue layer that is ablated per laser pulse, is 100 microns using pulse energies of 70 mJ. This means that formalin-fixed human tympanic membrane can be perforated with one single laser pulse. RESULTS: Ten patients with OME (otitis media with effusion) were treated under topical anesthesia of the tympanic membrane (8% tetracainbase in Isopropanol for 15 min) with focussed laser pulses (beam diameter 500 microns) with energies of 100 mJ (energy density 52 J/cm2). A sufficient perforation diameter of 2 mm could be achieved with an average of 15 juxtaposed laser applications. The enlargement of the perforations was made difficult by extruding middle ear secretions and slight bleeding of the tympanic membrane. Between laser applications, the target tissue had to be cleaned by suctioning using the operation microscope. The healing of the tympanic membrane was verified and compared in postoperative clinical follow-ups. With a perforation diameter of 2 mm, the Er:YAG laser myringotomies healed within 14 days. The used parameters did not generate side effects such as inner ear hearing loss. CONCLUTIONS: An effective, easy, and practical performance of laser myringotomy is not currently possible with the Er:YAG laserotoscope.     

Laserstapedotomie

In addition to hearing aids, stapesplasty represents the standard treatment of otosclerosis-induced hearing loss. In this procedure, the stapes superstructure is replaced by a prosthesis that is attached to the long process of the incus and communicates through a perforation in the footplate with the perilymphatic space of the inner ear. The removal of the stapes superstructure and perforation of the footplate are the critical steps of this surgical procedure. With the introduction of laser-assisted perforation techniques, the surgical safety of this method has been improved compared to conventional techniques. KTP, argon, as well as diode, Er:YAG and CO(2) lasers are used for stapedotomy. By using the CO(2) laser in conjunction with a scanner system, the number of laser applications required for the perforation of the footplate has been markedly reduced. In contrast to other systems, a more reproducible perforation diameter of the stapes footplate is achieved with a CO(2) laser equipped with a scanner. Complications such as uncontrolled leakage of perilymph, irradiation of inner ear structures or the occurrence of pressure waves with subsequent damage to the inner ear can be reduced by using a CO(2) laser. In this review, the surgical technique of CO(2) laser stapedotomy, including clinically established variants and paying particular attention to the one-shot technique, are described and discussed in comparison to other laser systems.     

30 years of stapes surgery

This study reports the results of otosclerosis surgery performed during the past thirty years (1973-2002) in the ENT Clinic in Katowice. The authors present difficult anatomic relationships in the tympanic cavity which might have an influence on stapes surgery. Audiometric evaluation of 100 bilateral stapedotomies performed in 50 patients revealed that a small--hole stapedotomy is a safe technique and could be performed bilaterally. The group of 55 stapedotomies with stapedial tendon preserved was compared to the group of 55 stapedotomies with dissected tendon. SRT was better in the group where the tendon was preserved. In the group of 32 patients ABR before and after stapedotomy was recorded. The latency of V wave after the operation was reduced to the normal values what indicated a correct function of the ossicular chain postoperatively. In the group of 60 patients DPOAE prior and after stapedotomy was evaluated. Prior to the operation no signal of otoacoustic emission was registered, in 37 patients out of 60 the signal was present after the operation. DPOAE obtained postoperatively indicated successful ossicular chain restoration and inner ear function. Audiometric evaluation in reference to the group of 905 stapedotomies performed in years 1992-2001 showed that most of the patients were in group B--443/905 and C--402/905 according, in A group--60/905 according to Shambaugh. A-B gap < or = 10 dB was obtained in 469/905 (51.8%), the mean of the hearing threshold at 500, 1000, 2000 and 4000 Hz was 24.3 dB (+/- 8.3, med. 25.0) in A group and 32.0 dB in B and C group. The result of stapedotomy in reference to tinnitus based on the patients' subjective opinion. We may conclude that the key to the stapes surgery lies in the training and skillfulness of the surgeon using save small hole technique with stapedial tendon preservation to obtain the optimal physiologic function of the middle ear and to gain the best hearing results.     

Technical and functional hearing results after unilateral stapes surgery for otosclerosis at Cluj-Napoca University Hospital

The aim of this study was to assess the hearing results after unilateral stapes surgery for otosclerosis at Cluj-Napoca University Hospital, and to evaluate surgical trauma to the inner ear in these patients. The medical records of 387 consecutive patients who underwent unilateral stapes surgery were reviewed. Hearing results were evaluated according to the 1995 American Academy of Otolaryngology-Head and Neck Surgery Committee on Hearing and Equilibrium guidelines and the Glasgow benefit plot. In addition we used Amsterdam plot to give an overview on air conduction gain and bone-conduction differences on an individual level. Results were analyzed separately for patients with preoperative unilateral, bilateral asymmetrical, and bilateral symmetrical hearing loss. Despite good technical hearing results after surgery (closure of the air-bone gap to ≤20 dB in 92 % of patients, air conduction gain of 24 ± 10.00 dB), only 37 % of patients achieved functionally normal, symmetrical hearing. Our results indicated that the pattern of preoperative hearing impairment in patients with otosclerosis can predict postoperative functional hearing results. The type of preoperative hearing impairment had.