Hypoglossal Nerve Transfer Surgery

In order to restore the resting symmetry or “tone” of the face, the hypoglossal nerve may be used as a donor nerve. The hypoglossal nerve helps to move the tongue.  In order to preserve this important function, the hypoglossal nerve can be partial cut on its side and connected to the facial nerve (see Figure 1). Due to the importance of tongue movement to speech and swallowing, the hypoglossal nerve is not cut completely, but is instead partially cut to allow nerves to grow into the facial nerve without cutting the entire hypoglossal nerve. This typically preserves normal tongue movement.  Patients will notice improved tone at rest about one year after the procedure, as shown in Figure 2.

Figure 1: illustration of a hypoglossal nerve transfer surgery. Note that the facial nerve is cut and redirected to the side of the hypoglossal nerve. This usually preserves the function of the hypoglossal, which moves part of the tongue.

Figure 2: patient of Dr. Pepper’s before and after hypoglossal nerve transfer surgery

Is this procedure for me?

In general, patients must have facial paralysis for no more than two years prior to this procedure.  After about two years of facial paralysis, the nerve may scar shut and no longer accept a new nerve supply.  Patients must also have a hypoglossal nerve that works normally.  In some cases of tumor or trauma, the hypoglossal nerve or the trigeminal nerve may not work normally and may not be usable for nerve transfer surgery.  In addition, patients who have difficulty swallowing are typically not good candidates for hypoglossal nerve transfer surgery.  In general, this procedure is effective for improving facial symmetry at rest, but will not provide restoration of smile.