Immunodiffusion and Immuno-histochemical Investigations on the Reactivity of Oxide Ceramic Middle-Ear Implants

ORL ◽  
1993 ◽  
Vol 55 (4) ◽  
pp. 216-221 ◽  
Author(s):  
A. Schadel ◽  
G. Thun ◽  
L. Stork ◽  
R. Metzler
Keyword(s):  
Middle Ear ◽  
Oxide Ceramic ◽  
Middle Ear Implants

Interposed Cartilage as a Precaution against Extrusions of Ceramic Ossicular Replacement Implants

1987 ◽  
Vol 96 (2) ◽  
pp. 207-209 ◽  
Author(s):  
Christoph Zöllner
Keyword(s):  
Middle Ear ◽  
Ossicular Chain ◽  
Oxide Ceramic ◽  
Small Disk ◽  
Middle Ear Implant ◽  
Ossicular Replacement ◽  
Middle Ear Implants ◽  
Aluminum Oxide Ceramic ◽  
Postoperative Observation

Since 1980 we have used middle ear implants of aluminum oxide ceramic in some reconstructions of the ossicular chain. We had opportunities to examine 108 ears (91 patients); the longest period of postoperative observation was 4 years. Follow-up examinations showed that the rates of extrusion and liability to extrusion can be reduced by interposing a small disk of autologous cartilage and perichondrium. Moreover, interposing cartilage tends to improve audiometric results. On the basis of our study, we strongly recommend the interposition of a disk of autologous cartilage and perichondrium between the middle ear implant and eardrum when an Al2O3 implant is used.

scholarly journals Design Study of a Round Window Piezoelectric Transducer for Active Middle Ear Implants

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 946
Author(s):  
Dong Ho Shin
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Middle Ear ◽  
Piezoelectric Transducer ◽  
Round Window ◽  
Piezoelectric Element ◽  
Sensorineural Hearing ◽  
Flat Band ◽  
Middle Ear Implants ◽  
Output Characteristics

This report describes the design of a new piezoelectric transducer for round window (RW)-driven middle ear implants. The transducer consists of a piezoelectric element, gold-coated copper bellows, silicone elastomer (polydimethylsiloxane, PDMS), metal cylinder (tungsten), and titanium housing. The piezoelectric element is fixed to the titanium housing and mechanical resonance is generated by the interaction of the bellows, PDMS, and tungsten cylinder. The dimensions of PDMS and the tungsten cylinder with output characteristics suitable for compensation of sensorineural hearing loss were derived by mechanical vibrational analysis (equivalent mechanical model and finite element analysis (FEA)). Based on the results of FEA, the RW piezoelectric transducer was implemented, and bench tests were performed under no-load conditions to confirm the output characteristics. The transducer generates an average displacement of 219.6 nm in the flat band (0.1–1 kHz); the resonance frequency is 2.3 kHz. To evaluate the output characteristics, the response was compared to that of an earlier transducer. When driven by the same voltage (6 Vp), the flat band displacement averaged 30 nm larger than that of the other transducer, and no anti-resonance was noted. Therefore, we expect that the new transducer can serve as an output device for hearing aids, and that it will improve speech recognition and treat high-frequency sensorineural hearing loss more effectively.

Bone Resorption Induced by Middle-Ear Implants

1986 ◽  
Vol 112 (6) ◽  
pp. 635-641 ◽  
Author(s):  
M. D. McGinn ◽  
R. A. Chole ◽  
S. P. Tinling
Keyword(s):  
Bone Resorption ◽  
Middle Ear ◽  
Middle Ear Implants

Hydroxylapatite Ossicular Replacement Prostheses: A Four-Year Experience

1992 ◽  
Vol 106 (3) ◽  
pp. 261-269 ◽  
Author(s):  
Robert A. Goldenberg
Keyword(s):  
Surgical Technique ◽  
Middle Ear ◽  
Control Group ◽  
Hearing Results ◽  
Extrusion Rate ◽  
Hearing Result ◽  
Ossicular Replacement ◽  
Middle Ear Implants

Between 1987 and 1991, I have used 215 hydroxylapatite middle ear implants, in various styles, for hearing reconstruction. The first such implants were composed entirely of hydroxylapatite. Because of intraoperative difficulties in shaping and trimming these prostheses, hybrid prostheses using Plasti-Pore were developed. For each of four implant designs (incus, incus-stapes, PORP, and TORP), the head is constructed from hydroxylapatite and the shaft from Plasti-Pore. Extrusion rate for the hybrid prostheses is low (4.3%). Hearing results from 47 patients with the hybrid hydroxylapatite prostheses, 140 patients with total hydroxylapatite prostheses, and 75 control group patients with homograft bone or Plasti-Pore prostheses were compared. A “successful” hearing result was achieved in 51.1%, 51.4%, and 60.0% of the three groups, respectively. Surgical technique for use of the new hybrid hydroxylapatite prostheses is described.

Middle Ear Implants

Hearing ◽  
2015 ◽  
pp. 107-112
Author(s):  
Neil Donnelly
Keyword(s):  
Middle Ear ◽  
Middle Ear Implants

Middle Ear Implants

2018 ◽  
pp. 1169-1176
Author(s):  
Maarten J.F. de Wolf ◽  
Richard M. Irving
Keyword(s):  
Middle Ear ◽  
Middle Ear Implants

scholarly journals Comparative study of efficiency and characteristics of FMT and DRT installed in human cadavers for round-window stimulation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dong Ho Shin ◽  
Jong Hoon Kim ◽  
Peter Gottlieb ◽  
Yona Vaisbuch ◽  
Sunil Puria ◽  
...  
Keyword(s):  
Middle Ear ◽  
Hearing Aids ◽  
Round Window ◽  
Standard Of Care ◽  
Acoustic Hearing ◽  
Middle Ear Implants ◽  
Human Cadavers ◽  
Limited Frequency ◽  
Output Characteristics ◽  
Temporal Bones

AbstractAcoustic hearing aids generate amplified sound in the ear canal, and they are the standard of care for patients with mild to moderate sensorineural hearing loss. However, because of their limited frequency bandwidth, gain, and feedback, there is substantial room for improvement. Active middle ear implants, which directly vibrate the middle ear and cochlea, are an alternative approach to conventional acoustic hearing aids. They provide an opportunity to improve sound quality and speech understanding with amplification rehabilitation. For floating-mass type and direct-rod type (DRT) middle ear transducers, a differential floating-mass transducer (DFMT) and a tri-coil bellows transducer (TCBT), respectively, were fabricated to measure the output characteristics in four human temporal bones. Both were fabricated to have similar output forces per unit input and were placed in four human temporal bones to measure their output performances. The TCBT resulted in higher output than did the DFMT throughout the audible frequency range, and the output was more prominent at lower frequency ranges. In this study, we showed that DRT was a more effective method for round window stimulation. Because of its frequency characteristics and vibration efficiency, this implantation method can be utilized as a driving solution for middle ear implants.

scholarly journals Validation of methods for prediction of clinical output levels of active middle ear implants from measurements in human cadaveric ears

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Martin Grossöhmichen ◽  
Bernd Waldmann ◽  
Rolf Salcher ◽  
Nils Prenzler ◽  
Thomas Lenarz ◽  
...  
Keyword(s):  
Middle Ear ◽  
Validation Of Methods ◽  
Middle Ear Implants
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