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the long process of the incus. Now comparative studies with other types of rithm had to be developed to simulate acoustical stimulation using electro-
prostheses and a longer follow-up are required to assess the long-term results. mechanical stimulation.
Results: Optimal tight crimping of the stapes piston revealed consistent
good sound transfer function ranging from 0 to 7 dB loss, and loss re-
K- PIS T ON mained, 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
Diagnostic Findings in Stapes Revision Surgery- up to 28 dB. A close coupling at least at two opposite points was obligatory
A Retrospective of 26 Years to obtain consistently good results.
Schimanski G., Schimanski E., Berthold M.R. Conclusions: Perfect hearing reconstruction necessitates ideal crimping of
a prosthesis to obtain consistently good results. However, the final function-
Published: Otology & Neurotology: April 2011 - 32(3): 373-383. al gain depends on many different intraoperative and postoperative factors.
DOI: 10.1097/MAO.0b013e3182096da1
Objectives: The aim of the study is to obtain a detailed overview of the Retrospective analysis of early postoperative hearing
revision findings after stapes operations and to draw conclusions on a stapes results obtained after stapedotomy with implantation of a
prosthesis that can be recommended. new titanium stapes prosthesis
Study Design: Retrospective case series. Setting: Tertiary otologic referral Zuur C. L., de Bruijn A. J. G., Lindeboom R., Tange R. A.
center.
Published: Otology & Neurotology 24:863-867 (2003)
Methods: Approximately 12,000 middle ear operations within a period of
26 years were evaluated. The findings of the revisions were classified into Objective: To evaluate the early postoperative hearing results of a new
surgeon related, prosthesis related, and other causes. titanium stapes prosthesis (K-Piston) implanted in patients with otosclerosis.
Results: Three hundred forty-three stapes revisions were done. Many differ- Study Design: A retrospective analysis of preoperative and early postopera-
ent prostheses were found: the most common were Schuknecht prostheses tive hearing thresholds. Setting: One tertiary referral and teaching hospital.
and Teflon platinum, gold, and titanium pistons. Polyethylene strut, Teflon Patients: Eighteen men and 40 women, mean age 47 years, with otosclero-
wire pistons, Shea (Teflon) pistons, and other techniques, such as columel- sis. Intervention: Primary stapedotomy.
la or malleovestibulopexy, were rarely found. There are specific findings
correlating to certain prostheses: Schuknecht prostheses were too short in Main Outcome Measure: Main outcome measures were the mean gains
50% of the revisions (surgeon related), Teflon platinum caused necrosis or in bone-conduction and air-conduction pure-tone thresholds, and pure-tone
arrosion of the long incudal process (prostheses related) in 69%, and gold averages for different frequency combinations. Success and failure of the
caused reparative granuloma sometimes combined with necosis of the incus individual cases were presented using Amsterdam Hearing Evaluation Plots.
in 70% (prostheses related). There was no specific diagnostic finding with
titanium pistons, neither surgeon nor material related. Results: The overall postoperative air-bone gap for the frequency combi-
nation 0.5-1-2-4 kHz was 8.4 (standard deviation: 5.2) dB. In 79% of the
Conclusion: An analysis of revision findings over an extended observation patients the postoperative air-bone gap was less than 10 dB. Air-conduction
period can enable middle-ear surgeons to improve their surgical techniques improved even in higher frequencies, while the Carhart effect was not seen
and to select the best suited prosthesis. Self-fabricated stapes prostheses in most cases. In three patients a deterioration of bone-conduction was ob-
(e.g., Schuknecht) do not conform to required quality standards and should served ranging from 11 to 16 dB sound pressure level (SPL), and in four
not be used. GoPi, which is no longer available, and TPlPi showed prosthe- patients the gain in air-conduction was insufficient (3-29 dB SPL) to close
sis-related diagnostic findings. The titanium prostheses used by the authors the preoperative air-bone gap to within 20 dB.
have proven to be excellently compatible and can therefore be recommend-
ed as safe stapes prostheses. Conclusion: The new low-weight, full-titanium stapes prosthesis with its
slight rough surface and its good mechanical stability and biocompatibility
can safely and successfully restore the function of the middle ear when im-
Stapes Prosthesis Attachment: The effect of Crimping on planted in patients with otosclerosis.
Sound Transfer in Otosclerosis Surgery

Huber A. M., Ma F., Felix H., Linder T.
SOFT CLIP
Published: Laryngoscope 2003 May;113(5):853-8. Poster Abstract (German)
DOI: 10.1097/00005537-200305000-00015
Experimental study on admissible forces at the
Objectives/Hypothesis: Although in stapes surgery successful hearing incudomalleolar joint
improvement may be achieved in the majority of patients, unsatisfactory
closure of the air-bone gap can be recorded. One of many reasons for unex- Lauxmann M., Heckeler C., Beutner D., Lüers J. C.,
pected failures of stapes surgery may be the insufficient crimping of a stapes Huettenbrink K.-B., Chatzimichalis M., Huber A., Eiber A.
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 Published: Otol Neurotol. 2012 Aug;33(6):1077-84
crimping and to identify a required loop attachment pattern to obtain good DOI: 10.1097/MAO.0b013e318259b34b
sound transmission results.
Hypothesis: The forces that cause rupture of the incudomalleolar joint
Study Design: Experimental. during the fixation of stapedial prostheses can be determined by means of
load-deflection measurements at the long process of the incus. As in other
Methods: A temporal bone model was developed to measure the sound tissues, 3 ranges of forces can be defined: micro rupture, rupture, and short-
transmission properties between incus and prosthesis on 17 fresh human term maximum.
temporal bones. The attachment of a titanium stapes piston was assessed
without crimping, followed by loose crimping and tight fixation to the Background: A crucial step in stapes surgery is the attachment of the stape-
incus, using scanning laser Doppler interferometry, endoscopic photogra- dial prosthesis to the long process of the incus. It is unknown which forces
phy, micro grinding technique, and scanning electron microscopy. An algo- occur during the crimping process that increase the risk of damage to the

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