Ear Center: MAXUM Hearing Implant

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Introduction: The Power to Hear
MAXUM Video 1: How the MAXUM works

How the MAXUM works
How the MAXUM is implanted
MAXUM Video 2: How the MAXUM surgery procedure is performed

Custom-Fit MAXUM sound processor
Clinical results
What are the indications and contraindications for the MAXUM
Screening Medical History Questionnaire for the Maxum Hearing Implant - download a copy

View Maxum Videos - click on the video below that you want to watch...


Introduction: The Power to Hear

The new MAXUM Hearing Implant is an FDA approved, semi-implantable electromagnetic middle ear implant for treatment of adults 18 years and older with moderate to severe sensorineural hearing loss, discrimination (word recognition ability) of equal to or greater than 60%, and who have had difficulty understanding speech using conventional hearing aids.

The MAXUM system (second generation) consists of two components:

  • Internal component: a tiny, titanium-encased, rare earth magnet that is surgically implanted in the middle ear (coupled to the ossicular chain)
  • External component: a deep insertion, completely-in-the-canal, open-fit, electromagnetic sound processor (IPC) that is worn in the external auditory canal, similar to a conventional hearing aid. The IPC sound processor is "speaker-less" and does not make any audible sounds or noises.


 MAXUM Sound Processor in the right ear canal. MAXUM magnetic implant attached to the hearing bones.

MAXUM Video 1: How the MAXUM Works

Please click on the "arrow" to view a video with subtitles about how the MAXUM works.


How the MAXUM Works: a semi-implantable middle ear implant

Two Components: The MAXUM system works with an internal component that consists of a magnetic implant that is attached to the hearing bones in the middle ear. A second component, an electromagnetic sound processor (IPC or Integrated Processor and Coil) is worn in the ear canal. The vented, custom-fit IPC looks like a long "In-the-Canal" hearing aid..

Direct Cochlear Stimulation: The IPC contains sound processing electronics, a battery, and an electromagnetic coil. The IPC receives sound from the ear canal, processes the sound signal for the individual's hearing loss, and transmits an electromagnetic signal from its tip (coil), through the eardrum, to a magnetic implant that has been attached to the hearing bones. The processed electromagnetic signal causes the magnetic implant to vibrate which, in turn, causes the hearing bones to vibrate. The sound vibrations then travel though the inner ear and stimulate hair cells and nerves that send impulses to the brain that are interpreted as meaningful sounds and speech.

Electromagnetic Advantages: Because the MAXUM device generates safe, inaudible, electromagnetic signals (speaker-less) in contrast to audible acoustic signals produced by the speakers of conventional hearing aids, the MAXUM is able to overcome the intrinsic functional limitations of acoustic hearing aids through direct cochlear stimulation:

  • Increased Power: can deliver more power and bandwidth than a conventional hearing aid (up to 60 dB of functional gain, from 125 - 12,000 Hz)
  • Little or No Feedback: has little or no feedback because there is no acoustic sound to leak back to a microphone
  • Increased Comfort: has large vents that prevent ear canal occlusion problems
  • Increased Fidelity due to Low Distortion: direct cochlear stimulation provides a clear signal with improved sound quality and speech understanding because acoustic distortion is reduced or eliminated.
  • Good for High Frequency Hearing Loss: is particularly good for patients with high frequency hearing loss, a condition that is difficult to treat with conventional hearing aids.


How the MAXUM is Implanted: a minimally invasive outpatient procedure

Outpatient Procedure Under Local Anesthesia: At the Ear Center, the procedure is performed as same-day-surgery at the SCA Surgical Center of Greensboro, an ambulatory surgery center. The MAXUM is implanted using a minimally invasive operation performed as an outpatient and usually takes less than one hour.

Operation: Using local anesthesia with sedation and operating through the ear canal, the middle ear is exposed, and the magnetic implant is coupled to the hearing bones. Either a "twist & split" coupling is used as shown below or a Nitanol "split ring" coupling is used. The hearing bones are not separated during the procedure. No crimping is necessary. The procedure is reversible; the magnetic implant can be removed if necessary.

Right middle ear before MAXUM implant.
MAXUM implant attached to hearing bones.
MAXUM implant secured with cement.


Postoperative Care: Patients are discharged the same day after a brief recovery period. Overnight stay is not required. Postoperative medications include mild pain relievers and gentle ear drops for one week. Patients may return to work the next day, may not fly in an airplane for three weeks, and should avoid water exposure of their ear for 3 weeks. Implant turn-on is performed approximately 4 weeks postoperatively to permit complete healing.


MAXUM Video 2: How the MAXUM Surgery Procedure is Performed

Please click on the "arrow" to view a video about how the MAXUM surgery procedure is performed.


Custom-Fit MAXUM Digital Sound Processor: Integrated Processor & Coil (IPC)

Orientation: The MAXUM sound processor uses electromagnetic principles instead of acoustic principles like a conventional hearing aid. Because of this, the tip of the sound processor extends into the ear canal further than a conventional hearing aid and must be oriented correctly for optimum function. Proper orientation requires an adequate sized ear canal without sharp bends or narrowings, healthy skin, and a custom-fit sound processor.

Custom-Fit Sound Processor: In order to create a custom-fit sound processor for each individual, it is necessary to make a mold of the ear canal. The mold is made at the Ear Center by an audiologist and takes about 30 minutes. The ear canal is cleaned, anesthetized with a topical anesthetic solution, lubricated, and injected with mold material. After curing, the mold is removed and measured to determine if a sound processor can be made that will properly fit the ear canal. Some individuals with extremely narrow ear canals or sharp bends may not be able to wear a MAXUM sound processor and would not be able to receive a MAXUM.

Individualized Programming: After your custom-fit MAXUM digital sound processor has been manufactured, one of our specially trained audiologists will computer program your device using MAXUM software. Programming will be tailored to your hearing loss and individual preferences. If your hearing should change, your sound processor may be reprogrammed at any time.

Battery: The MAXUM sound processor uses a standard hearing aid battery and is user replaceable.

Clinical Results

In a recent clinical study, MAXUM improved patients' gains, when compared to their hearing aids, by an increase of 7.0 - 7.9 dB in pure tone averages and 9.2 - 10.8 dB in the high frequencies. Every 3 dB change is a doubling of the power. Individual results may vary depending on multiple variables.

Most patients in the clinical trial reported less ear canal occlusion, better sound quality, less feedback, and greater satisfaction with the MAXUM as compared to their hearing aids.



What are the Indications and Contraindications for the MAXUM?


  • Adults, 18 years or older
  • Moderate to severe sensorineural hearing loss
  • Unaided word recognition scores of 60% or greater at PB Max (Power intensity function or UCL-5 recommended)
  • Adequate size ear canal to accommodate the MAXUM sound processor
  • Normal middle ear anatomy

Maxum Implant Fitting Profile:


The Maxum FDA approved fitting profile expanded to thresholds of 100 dB at 2 KHz and above.

Recommendations for Audiologists:

  • While in the sound field, test the patient's monaural Aided WRS @ 50 dB HL for each ear (plug contralateral ear)
  • Calculate the "Speech Performance Gap": SPGap = PB Max - Aided WRS
  • Complete Candidacy Worksheet

Ideal Candidates (at least two of the following):

  • Unaided PB Max score > 60%
  • Aided WRS at 50 dB HL < 80%
  • Speech performance gap
  • Dissatisfaction with hearing aids


  • Less than 18 years of age
  • Conductive or mixed hearing loss
  • Retrocochlear or central auditory disorders
  • Active middle ear infections
  • Eardrum (tympanic membrane) perforations associated with frequent infections
  • Disabling ringing (tinnitus)
  • Absent hearing bones
  • Need for MRI scanning
  • Inadequate ear canal for Maxum Sound Processor (determined by preoperative Maxum ear mold) 


Screening Medical History Questionnaire for the Maxum Hearing Implant


Click here to download a copy of our Screening Medical History Questionnaire for the Maxum Hearing Implant,



1. Hough JV, Dyer RK, Matthews P, Wood MW. Semi-implantable electromagnetic middle ear hearing device for moderate to severe sensorineural hearing loss. Otolaryngol Clinics NA 2001;34(2):401-16.

2. Hough JVD, Matthews P, Wood MW, Dyer RK. Middle ear electromagnetic semi-implantable hearing device: results of the phase II SOUNDTEC direct system clinical trial. Otol Neurotol 2002;23(6):895-903.

3. Dyer RK, Dormer KJ, Hough JVD, Nakmali U, Wickersham R. Biomechanical influences of magnetic resonance imaging on the SOUNDTEC Direct System implant. Otol HNS 2002;127(6):520-30.

4. Dyer RK, Nakmali D, Dormer KJ. Magnetic resonance imaging compatibility and safety of the SOUNDTEC Direct System. Laryngoscope 2006;116(8):1321-33.

5. Dyer K. The SOUNDTEC direct system: surgical technique. Cochlear Implants International. 2005;6 Suppl 1:69-72.

6. Hough JV, Dyer RK, Matthews P, Wood MW. Early clinical results: SOUNDTEC implantable hearing device phase II study. Laryngoscope 2001;111(1):1-8.


MAXUM, electromagnetic, active middle ear implant, middle ear, ossicular chain, glass-ionomer cement, titanium, hearing results, hearing loss, sensorineural hearing loss, rare earth magnet, direct driving of the ossicular chain, low distortion, digital sound processor, functional gain, Speech Performance Gap.

For more information concerning the MAXUM, please visit www.myMAXUM.com/ or call 877-410-HEAR or 281-203-0250. You may visit the manufacturer's website at www.ototronix.com/.

For more information concerning the MAXUM implant at The Ear Center, please call us at 1-336-273-9932 and ask to speak to an audiologist.

Last revised August 28, 2015