Understanding Cochlear Implants: Types and Choosing the Best Fit
- Lovedeep Kholia
- Jun 20
- 5 min read
One of the most transformative technologies for individuals with severe to profound hearing loss is the cochlear implant—a solution that goes far beyond traditional amplification. At Unicare, our audiology team has played an active role in multiple cochlear implantation programs across Delhi-NCR, and has undergone rigorous training at prestigious institutions both in India and internationally.
In this blog, we’ll explore the different types of cochlear implants available today, the unique features offered by leading manufacturers, and the critical factors to consider when choosing the implant that best suits a patient’s individual needs and lifestyle.
Cochlear Implants: A Breakthrough in Restoring Hearing and Communication
A cochlear implant is a sophisticated medical device designed to restore hearing in individuals with severe to profound sensorineural hearing loss who receive limited benefit from conventional hearing aids. Unlike hearing aids, which amplify sound, cochlear implants bypass the damaged hair cells in the inner ear and directly stimulate the auditory nerve using electrical signals. The system consists of an external sound processor and an internal implant that work together to capture, convert, and transmit sound. This technology not only improves sound perception but also significantly enhances speech understanding and communication abilities, especially in challenging listening environments. Cochlear implants have become a life-changing solution, enabling individuals to reconnect with their surroundings and lead more fulfilling, socially engaged lives.
Anatomy of a Cochlear Implant: How Its Parts Work Together to Restore Hearing
A cochlear implant system is composed of two main components—external and internal—that work in harmony to deliver sound directly to the auditory nerve. The external parts include a microphone, which picks up sound from the environment, a speech processor that analyzes and digitizes the sound signals, and a transmitting coil that sends these signals across the skin to the internal device via electromagnetic waves. The internal implant, surgically placed under the skin, consists of a receiver-stimulator that decodes the incoming signals and an electrode array that is carefully inserted into the cochlea. This array delivers electrical impulses to specific nerve fibers based on the frequency of sounds, allowing the brain to perceive them as meaningful audio input. Together, these components offer a sophisticated solution for individuals who cannot benefit from traditional hearing aids.
Understanding the Internal Implant
Inside our inner ear is a snail-shaped organ called the cochlea, which helps us hear. In people with severe hearing loss, the tiny hair cells inside the cochlea are damaged, so normal hearing aids don’t help much. That’s where a cochlear implant comes in.
The implant includes a thin wire called the electrode array, which is gently inserted into the cochlea during surgery. This wire has small metal parts (electrodes) that send tiny electric signals directly to the hearing nerve. Each part of the wire is placed in a way that matches different types of sounds—like high-pitched or low-pitched sounds.
When a person hears a sound, the outer device (worn on the ear) turns it into a special signal and sends it to the implant. The implant then sends this signal through the electrode array, helping the brain understand the sound. This lets people hear speech, sounds around them, and even enjoy music again.
Different types of internal implants
Internal cochlear implants come in various designs, each tailored to optimize performance, safety, and compatibility with different anatomical and medical needs.
Based on the placement of the electrode array within the cochlea, internal cochlear implants can be classified into three main types:
Lateral wall arrays: The lateral wall cochlear implant array is designed to lie along the outer wall of the cochlea, following its natural curvature with minimal insertion trauma. This type of electrode array is typically straight and flexible, allowing for a smoother insertion and reducing the risk of damage to the delicate structures within the cochlea, especially the modiolus and basilar membrane. It is often preferred in cases where preservation of residual hearing is a priority, such as in pediatric patients or individuals receiving electro-acoustic stimulation. Lateral wall arrays offer broad cochlear coverage and are suitable for varying cochlear anatomies, making them a reliable and widely adopted choice in many cochlear implantation programs.
Peri-modiolar arrays : A perimodiolar array is a type of cochlear implant electrode designed to closely hug the modiolus—the central core of the cochlea where the auditory nerve fibers are concentrated. This design allows for more focused electrical stimulation, potentially improving hearing outcomes by reducing the current spread and enhancing speech perception. Unlike lateral wall arrays that lie along the outer edge of the cochlea, perimodiolar arrays are pre-curved to wrap around the inner wall, bringing the electrodes closer to the target nerve structures. However, this proximity can also increase the risk of complications like tip fold-over or damage to delicate cochlear tissues if not inserted carefully. Advances like the Slim Modiolar electrode aim to minimize trauma while maintaining the benefits of perimodiolar placement. It's a fascinating intersection of engineering precision and auditory science.
Mid-scala arrays: A mid-scalar array is a type of cochlear implant electrode designed to sit midway between the lateral wall and the modiolus within the scala tympani of the cochlea. This positioning aims to strike a balance between the benefits of perimodiolar and lateral wall arrays—offering proximity to the auditory nerve fibers for effective stimulation while minimizing trauma to delicate cochlear structures. The HiFocus Mid-Scala electrode, for example, is pre-curved and engineered for atraumatic insertion, often via the round window, to preserve residual hearing and reduce the risk of translocation into other cochlear chambers. Its design supports a wide range of surgical techniques and patient anatomies, making it a versatile option in cochlear implantation. By maintaining a central path within the scala tympani, mid-scalar arrays can enhance speech perception outcomes while promoting long-term cochlear health. It's a thoughtful blend of precision and preservation.
Audiologist performing NRTs during cochlear implant surgery
MRI Compatibility in cochlear Implants
Cochlear implants are generally MRI-compatible, but with specific conditions depending on the implant model and the strength of the MRI scanner. Most modern implants are labeled MR Conditional, meaning they can safely undergo MRI scans if certain guidelines are followed—such as using a head wrap, removing the external sound processor, or even temporarily removing the internal magnet in some cases. Newer models, like the Cochlear™ Nucleus® Profile Plus Series, are designed to withstand both 1.5T and 3.0T MRI scans without magnet removal or discomfort, thanks to self-aligning magnets that reduce torque during imaging. It's essential for patients to carry their implant identification card and consult with radiology professionals to ensure the correct safety protocols are in place before undergoing an MRI. This compatibility ensures that recipients can still benefit from critical diagnostic imaging without compromising their hearing technology.
At Unicare Speech and Hearing Clinic in Delhi, cochlear implant services are led by a team of highly qualified specialists. Mr. Lovedeep Kholia, the chief audiologist, brings over 15 years of experience and holds a Master’s degree from the All India Institute of Speech & Hearing (AIISH), Mysuru. As President of the Delhi Speech & Hearing Association, he is widely respected for his expertise in cochlear implant mapping, auditory rehabilitation, and balance disorder management.
He is joined by Ms. Niyati Chopra, a seasoned audiologist and speech-language pathologist with more than 16 years of clinical experience. She has received advanced training in cochlear implant technology from Australia and Switzerland and plays a key role in post-implantation therapy at the clinic. Both Mr. Kholia and Ms. Chopra are certified Auditory Verbal Therapists (AVTs) and recognized experts in auditory training, ensuring that patients—especially children—receive comprehensive support in developing listening and spoken language skills after implantation. Their combined expertise makes Unicare a leading center for cochlear implant care and auditory rehabilitation.
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