Prevention of the Complication
Open TMJ Surgery
Penetration into the EAC can be avoided during open surgery by careful dissection of soft tissue while being mindful of the EAC proximity, direction, and orientation. The simplest way to avoid this complication is to maintain a plane of dissection anterior to the tragal cartilage down to the postglenoid tubercle. There is the possibility of entering the cartilaginous canal with this approach, but attention should be paid to following the natural angulation of the cartilage. Perforation of the bony canal is also possible particularly when removing bone during bony ankylosis release. In complex bony ankylosis cases, it is sometimes beneficial to utilize navigation surgery to confirm precise anatomic location in relation to surrounding vital structures including the EAC.
Arthroscopic TMJ Surgery
The risk of penetration into the EAC can be minimized during arthroscopic surgery by the use of appropriate force, direction, and precise spatial awareness. The greatest risk is during the initial arthroscopic puncture with the sharp trocar and cannula. McCain reported on a safe, repeatable, and effective puncture technique for single and multiple ports . Tanabe studied and reported the dangerous angles and depths associated with potential middle ear injury during arthroscopy .
The risk of inadvertent puncture into the EAC can be minimized by mindful consideration of puncture site, direction, depth, and force.