A cochlear implant is an advanced electronic hearing device that offers a sense of sound to individuals with severe hearing loss. The device is split into two parts, and only one is safe from moisture. The internal component is fully waterproof, but the external sound processor contains sensitive microelectronics and is highly susceptible to water damage unless specifically protected. Understanding the distinction between these components and following proper care protocols is necessary for maintaining the device’s function.
The Vulnerable Components of a Cochlear Implant
Cochlear implants consist of two main sections: the internal implant and the external sound processor. The internal implant is a receiver-stimulator surgically placed beneath the skin and hermetically sealed within a titanium casing. This robust seal ensures the internal device is entirely protected from bodily fluids and environmental moisture.
The external sound processor captures and processes sound signals before transmitting them to the internal component. This external unit includes the microphone, battery pack, and coil, all of which house sensitive electronics vulnerable to moisture. Even light rain, heavy perspiration, or humidity can cause issues, and full submersion will likely lead to damage if the processor is not specifically prepared. Most modern processors have some degree of water resistance, often indicated by an Ingress Protection (IP) rating, but this is not the same as being fully waterproof.
Protocols for Planned Water Activities
For intentional water exposure, such as showering or swimming, the external processor must either be removed or protected with manufacturer-approved accessories. Standard external processors should always be taken off before bathing, as even splashing water can damage the delicate components. Specialized waterproof accessories have been developed to allow users to hear while participating in water activities.
Waterproof Accessories and IP Ratings
These accessories, such as waterproof sleeves or cases like the AquaCase or WaterWear, encase the processor and coil in a watertight housing. Many specialized kits achieve a high-level IP rating, such as IP68, which signifies protection against continuous submersion in water up to a certain depth for a specified time. Some newer processors are rated IP68 without an accessory, meaning they can be submerged in fresh water for up to an hour at a depth of one meter.
When using these accessories for swimming, certain non-zinc-air batteries may be required, as zinc-air batteries need oxygen to function. After swimming, follow post-exposure care instructions, especially if the accessory or processor was exposed to saltwater or chlorinated water. This involves thoroughly rinsing the waterproof accessory with fresh water before drying, as chlorine and salt residue can be corrosive.
Emergency Care for Accidental Wetting
If the external sound processor is unintentionally exposed to water, immediate action is required to prevent permanent damage. The first step is to power off the device completely and remove the battery; disposable batteries should be discarded immediately.
Next, use a soft, lint-free cloth to gently wipe the exterior of the processor, focusing on the microphone ports and the battery compartment to remove visible moisture. The processor should then be placed in a specialized electronic drying unit, such as a dehumidifier or a desiccant kit, for an extended period, usually overnight. These kits use a gentle warming cycle or a desiccant material, like silica gel, to draw out microscopic moisture from the internal circuitry.
It is important to never attempt to speed up the drying process using heat sources like a hairdryer or oven, as intense heat can melt or warp the plastic casing and damage the internal components. After the recommended drying time, insert a fresh battery and test the device. If the processor shows signs of intermittent function, static, or fails to turn on, contact an audiologist or cochlear implant clinic for professional inspection or repair.