Conventional Stapedotomy Research Articles

Endoscopic stapedotomy: A comparison between the conventional approach versus CO2 laser-assisted surgery.

Although the utility of laser fiber in microscopic stapes surgery has been documented in the past, their role can be highly emphasized in endoscopic stapes surgery, especially in difficult anatomical situations. This is a retrospective analysis of cases where a total of 46 patients (22 in conventional stapedotomy and 24 in CO2 laser-assisted stapedotomy) were included in the study. The clinical parameters were assessed both in the preoperative and postoperative periods in the respective groups and later compared 12 weeks after stapedotomy. A total of 90.90% (20/22) of the patients in the conventional stapedotomy and 95.83% (23/24) of patients in laser-assisted stapedotomy had <20 dB of AB gap in the postoperative period (P = 0.71). Canaloplasty was required in six patients in the conventional stapedotomy and none of the patients in the laser group needed the same (P = 0.01). Chorda tympani nerve was manipulated in 59.09% (13/22) and 25.00% (6/24) of cases in the conventional group and in the CO2 laser group, respectively (P = 0.01). Although the audiological outcomes with fiber-enabled CO2 laser in endoscopic stapedotomy are comparable to conventional surgery, it is a better tool in a narrow auditory canal, requiring minimal manipulation of the chorda tympani nerve.

Conventional approaches versus laser CO2 surgery in stapes surgery: a multicentre retrospective study.

To analyze and compare surgical and audiological outcomes of conventional approaches versus laser CO2 surgery in stapes surgery. 333 patients who underwent stapes surgery were enrolled in the study; the patient population was divided into three groups: group 1: 170 patients treated with conventional stapedotomy with manual microdrill (average age 49.13years); group 2: 119 patients treated with conventional stapedotomy with electrical microdrill (average age 51.06years); group 3: 44 patients (average age 50.4years) who underwent CO2 laser stapedotomy. Intra-operative, postoperative outcomes and audiological results were investigated. The average surgical time of laser CO2 surgery was longer than for other surgical procedures. No statistical differences emerged in post-operative abnormal taste sensation. There was also no difference in postoperative dizziness. Air-bone gap (ABG) went down from 29.7 ± 10dB (group 1) and 27.32 ± 9.20 (group 2) to 10 ± 6.9dB (group 1) and 10.7 ± 6.03dB (group 2). In group 3 the preoperative ABG was lowered from 28.3 ± 10.1 to 11.8 ± 10.9, with a statistical difference in auditory recovery (p = 0.0001); The group of patients treated with laser CO2 showed a percentage of patients with an ABG closure of between 0 and 10dB higher than in the group treated with manual microdrills (77.2% vs. 60%, respectively; p = 0.03). Overall surgical results of CO2 laser and conventional stapedotomy are comparable without any significant difference; however, the group treated with CO2 laser appears to have a percentage of patients with an ABG closure 0-10dB higher than the group treated using the conventional technique.

Endoscopic Stapedotomy: Overcoming Limitations of Operating Microscope

The study is aimed to assess the scope of endoscopic stapedotomy in overcoming technical challenges faced during conventional stapedotomy using operating microscope. Sixty-four patients with clinical and audiological diagnosis of otosclerosis were randomly assigned into one of the 2 groups-one underwent conventional stapedotomy using operating microscope, while the other group underwent endoscopic stapedotomy, the operating surgeon being the same for both groups, for all cases. The 2 groups were observed in terms of extent of the postero-superior canal bone curettage/drilling, chorda tympani repositioning, visualization of footplate area, surgical time from first incision to ear packing, post-operative morbidity in terms of post-operative pain, vertigo, hearing outcome, and changes in taste sensation. It was observed that irrespective of the width of the external auditory canal, endoscopic approach offered better access to the footplate area requiring lesser bone removal and chorda tympani repositioning. The operating time, post-operative pain, and changes in taste sensation were significantly less in the endoscopic group. However, no difference was noted in terms of the post-operative hearing outcome and incidence of vertigo. Endoscopic stapedotomy has clear advantages in terms of the technicality and accessibility to the working area as well as faster recovery.

The effect of static force on round window stimulation with the direct acoustic cochlea stimulator

The Direct Acoustic Cochlea Stimulator Partial Implant (DACS PI, Phonak Acoustic Implants SA, Switzerland) is intended to stimulate the cochlea by a conventional stapedotomy piston that is crimped onto the DACS PI artificial incus. An alternative approach to the round window (RW) is successfully done with other devices, having the advantage of being also independent of the existence of middle ear structure (e.g. ossicles). Here the possibility of stimulating the RW with the DACS actuator is investigated including the impact of static force on sound transmission to the cochlea.The maximum equivalent sound pressure output with RW stimulation was determined experimentally in fresh human temporal bones. Experiments were performed in analogy to the ASTM standard (F2504.24930-1) method for the output determination of implantable middle ear hearing devices (IMEHDs) in human cadaveric temporal bones (TBs). ASTM compliant temporal bones were stimulated with a prosthesis having a spherical tip (∅0.5 mm) attached to the actuator. The stimulation was performed perpendicular to the round window membrane (RWM) at varying position relative to the RW and the resulting static force on the RW membrane was determined.At each position the displacement output of the DACS PI actuator and the stapes footplate (SFP) vibration in response to actuator stimulation was measured with a Laser Doppler Velocimeter (LDV). By comparison of the achieved output at the stapes footplate in response to sound and transducer stimulation the equivalent sound pressure level at the tympanic membrane at 1Vrms input voltage was calculated assuming that the SFP displacement in both conditions is a measure of perceived loudness, as it is done in the ASTM standard.Ten TB preparations within the acceptance range of the ASTM standard were used for analysis. The actuator driven stapes footplate displacement amplitude as well as the resulting equivalent sound pressure level was highly dependent on the static force applied to the RW. The sound transfer efficiency from the RW to the stapes footplate increased monotonically with increasing static load. At a moderate static force load (approx. 3.9 mN) the obtained average sound equivalent sound pressure level was 102–120 eq. dB SPL @ nominally 1Vrms input for frequencies ≤4 kHz. At higher frequencies (6–10 kHz) the achieved output dropped to ∼90 dB SPL.This output was obtained at loading conditions compatible with the actuator safe operating range, although it was possible to increase the output further by increasing the static force load.Our results demonstrate for a first time that static force applied to the RW is crucial for sound transmission efficiency. Further we could show that RW stimulation with the DACS PI actuator is possible having a maximum output that is sufficient to treat moderate and pronounced sensorineural hearing losses (SNHL).This article is part of a Special Issue entitled “MEMRO 2012”.

Clinical Results After Stapedotomy

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 ≤20 dB air-bone gap after 57 wk) could be found in Group B. Conclusion: If certain rules to minimize inner ear trauma are followed, the Er:YAG laser is a safe tool in middle ear surgery. Combining both the laser and the conventional technique, instead of the separate use of either technique, leads to superior postoperative hearing results.

Clinical Results After Stapedotomy

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. Retrospective review of prospectively collected audiometric data of patients with otosclerosis operated on by one experienced surgeon. Academic tertiary referral center. 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. 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). Pure-tone audiometry was performed before surgery, 2 days postoperatively (bone conduction only) and at 5, 26, and 57 weeks postoperatively. 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 <or=20 dB air-bone gap after 57 wk) could be found in Group B. If certain rules to minimize inner ear trauma are followed, the Er:YAG laser is a safe tool in middle ear surgery. Combining both the laser and the conventional technique, instead of the separate use of either technique, leads to superior postoperative hearing results.

Cochleaprotektion und chirurgische Präzision bei der Er:YAG-laserchirurgischen Stapedotomie

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. 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. 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. 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.

Erbium: Yttrium-Aluminum-Garnet Laser Application in Stapedotomy

To assess clinical safety and efficacy of the erbium: yttrium-aluminum-garnet (Er:YAG) laser in the stapes surgery; to define and optimize parameters that render the procedure safe for the inner ear. Retrospective study. A microscope-integrated Er:YAG laser stapedotomy was performed on 29 patients and a conventional stapedotomy on 41 patients. An early (within 1 to 3 days after stapes surgery) and late (at least 6 weeks) pure-tone bone-conduction threshold audiogram was obtained. No statistically significant differences were found by Student's t test over all measured frequencies between pre- and postoperative bone-conduction thresholds in each group. There was no statistically significant difference for all frequencies between early (3 days) and late postoperative mean bone-conduction thresholds. The results of our preliminary clinical study showed that erbium laser poses no risk to inner ear function. However, the lack of standardization obliges further investigation to establish safe clinical parameters of the Er:YAG laser.

Laser stapedotomy minus prosthesis (laser STAMP): absence of refixation.

To determine what percentage of patients with otosclerosis could successfully undergo a laser stapedotomy minus prosthesis over a 5-year period, and to determine the percentage of patients in whom refixation develops during follow-up. Retrospective case review of 136 patients (137 ears) who underwent primary surgery for otosclerosis. An otology/neurotology tertiary referral center. Patients were chosen if they had clinical evidence of otosclerosis without a history of otologic surgery. A standard stapes approach was used for all patients. For the laser stapedotomy minus prosthesis, a hand-held laser probe was used to vaporize the anterior crus of the stapes and perform a linear stapedotomy across the anterior one third of the footplate. If otosclerosis was confined to the fissula ante fenestram, the stapes became completely mobile. The stapedotomy opening was sealed with an adipose tissue graft from the ear lobe. Pure-tone audiometry with appropriate masking and auditory discrimination testing was performed before surgery, 6 weeks after surgery, and every year thereafter. Of the 137 cases, favorable anatomy and minimal otosclerosis allowed 46 (33.6%) of these patients to undergo laser stapedotomy minus prosthesis. Fifty-seven patients (41.6%) could not undergo the procedure because of extensive otosclerosis. The remaining 34 patients (24.8%) did not receive laser stapedotomy minus prosthesis because of other anatomic or technical difficulties. Of the 34 patients in the laser stapedotomy minus prosthesis group with more than 4 months follow-up, the average air-bone gap was closed from a mean of 22 dB (SD 10 dB) to 6 dB (SD 4 dB) 6 weeks postoperatively. Follow-up periods ranged from 5 months to 53 months (mean 767 days, SD 437 days). The long-term air-bone gap improved slightly to an average of 5 dB (SD 6 dB) in comparison with the sixth postoperative week value. Laser stapedotomy minus prosthesis is a minimally invasive procedure, which over the follow-up period has a very low incidence of refixation, as evidenced by a lack of progressive conductive hearing loss. The success of this procedure depends on the correct selection of cases. This procedure has been successfully performed on 33.6% of patients undergoing primary stapes surgery. Laser stapedotomy minus prosthesis seems to be a viable alternative to conventional stapedotomy that yields good results without evidence of refixation over an extended time.

Is the Er:YAG laser damaging to inner ear function?

To assess whether the use of the Er:YAG laser in middle ear surgery has negative effects on inner ear function. Prospective. Forty-nine patients with a 4- to 18-month postoperative audiologic follow-up were included in the study (24 stapedotomies, 23 malleostapedotomies, 1 surgery for congenital ear atresia, and 1 tympanoplasty). Twenty patients with conventional stapedotomy formed a control group. No statistically significant differences in preoperative and postoperative bone conduction thresholds and no impairment of postoperative air conduction thresholds were found. There was no significant difference between the results of the laser and the conventional stapedotomy. In addition, no relevant correlation between applied laser energy and postoperative hearing results were found. In summary, the authors were unable to find a negative effect of the Er:YAG laser on inner ear function at the 4- to 18-month audiometric follow-up. The clinical use of the Er:YAG laser with the system used in this study poses no risk to inner ear function if the total amount of energy is kept within the limits applied in this study.