So You Want to Talk About Implants?
So You Want to Talk About Implants?
The implant procedure is often the biggest barrier when it comes to discussing Bone Anchored Hearing Systems (BAHS) as a treatment option. The goal of this article is to provide you with all the necessary information to make an informed decision about BAHS and prepare for your quick 15-30 minutes implant procedure.
Before Your Procedure
Here are some tips to prepare yourself the day before:
- Follow all necessary instructions from your doctor before the procedure.
- Make sure to have a good night’s sleep and stay hydrated.
- It is natural to be nervous before the procedure, sharing your concerns with your doctor may ease your concerns.
- Have a family member/friend pick you up and drop you off or stay with you for support.
Types of Implants
In most cases, after trialing the device on a softband, people choose to go for a more permanent solution which involves an implant that integrates into the bone. The most common type of implanted BAHS is a percutaneous solution. The internal component is embedded into the skull and is attached to a piece that sticks slightly out of the skin called an abutment. The sound processor which contains the vibrating component is then clipped on the abutment and is not in contact with the skin.
Other implants involve using magnets to attach the external sound processor with the internal component. In one option, the vibrating piece is implanted (along with a magnet) and the sound processor is attached to the skin by a magnet. The other option still has an internal magnet; however, the vibrating piece remains in the external sound processor. In the latter, the sound must travel across the skin in the same way it does when wearing the device on a softband.
This article will explore the first type of implant surgery. The direct drive percutaneous solution. To learn more about the other bone conduction solutions, click here.
One type of procedure used by Oticon Medical is called MIPS (Minimally Invasive Ponto Surgery). It takes about 15 – 30 minutes to perform and often only requires local anesthesia. MIPS is a single stage procedure that reduces the risk of complications as it does not require a major incision or stitching afterwards. This minimizes scarring and encourages faster healing.
During MIPS, an otolaryngologist or Ear-Nose and Throat (ENT) doctor will do the following:
- Shave a very small area of hair behind the ear (1cm to 2 cm).
- Indicate the area where the implant will be placed, typically 50-55mm from the ear canal in the direction behind the ear.
- Measure skin thickness to determine abutment length.
- Receive a local anesthesia.
- Make a round hole with a skin (biopsy) punch about 5mm in diameter. Place the cannula to help guide the drill and minimize trauma to the surrounding area. A cannula is a thin tube inserted into a body cavity to help with the insertion of a surgical instrument.
- Drill a hole through the cannula into the skull bone.
- Screw a titanium implant into the bone. The implant is often attached to an abutment that sticks out through the skin. This is where the external part of the device will attach once the site is healed.
- Place a healing cap to ensure quick healing. It can be removed after 10-14 days or according to your surgeon’s instruction.
- Over time, the titanium implant integrates with the bone.
- After 4 weeks to 3 months (depending on healing process) the sound processor can then be attached onto the abutment and programmed by your audiologist.
This procedure is similar to that of MIPS however instead of using a biopsy skin punch, a linear incision behind the ear is made. A retractor pulls the skin apart to clear the way for the drilling of the hole and placement of the implant and abutment (typically already attached together for single stage).
Once the implant is in place, the surgeon will use the biopsy punch to punch a hole in the skin over where the abutment will poke through. The skin is then gently eased overtop of the abutment (lining up the hole with the abutment). The incision will then be sutured, and a healing cap placed.
Two stage procedures are often chosen for young children, individuals with thin or frail bone quality, or individuals with other medical conditions that may be contraindications for a single-stage procedure. In these cases, the abutment is not already attached to the implant when the implant is placed into the skull. Instead, a cover screw is attached to the implant and the incision site is sutured. After 3- 6 months allowing for appropriate osseointegration of the implant into the bone, the incision is opened, the cover screw is removed, and the abutment is installed. The incision is once again sutured, and a healing cap is placed.