Can Temporal Implants Cause Injury To The Facial Nerve?
Q: Dr. Eppley, I have read and is interested in your procedures concerning temporal implants, I have read that if placed on top the fascia the temporal branch that moves the forehead can be damaged, now I know there is also another nerve in that area which controls the upper eyelid muscles, so can this nerve also be injured if the implant is placed on top the deep fascia?
A: You are correct in assuming that the frontal branch of the facial nerve has the potential to be injured with placement of an implant on top of the deep temporal fascia. This small singular nerve branch is known to course through the tissue layer just above the deep temporalis fascia. While that tissue is easily raised off of the deep temporalis fascia, it can still be potentially injured during this dissection or even from the pressure of an implant beneath it. With frontal branch nerve injury, movement of the forehead (frontalis muscle) will be affected. If this nerve should be injured, recovery may or may not occur as this nerve branch has no cross-innervation from other nerve branches. For this reason, I generally place temporal implants deep to the fascia. But in some cases to get the desired aesthetic result, the implant must be placed on top of the deep fascia. and the potential risk of nerve injury must be accepted.
Frontal branch nerve injury, as might occur with a temporal implant placed above the deep temporal fascia, does not usually affect the eyelids. Sensory innervation of the eyelids is through terminal branches of the ophthalmic nerve (cranial nerve 1) and maxillary divisions of the trigeminal nerve. (cranial nerve 5) The levator palpebra superioris (upper eyelid levator nuscle) is innervated by the superior branch of the oculomotor nerve. (cranial nerve 3) This is why when one looks upward, the eyelid moves upward as well.
Dr. Barry Eppley