Selective Myectomy for Facial Synkinesis
Selective myectomy is a targeted microsurgical procedure that selectively transects or partially excises hyperactive facial muscle fibers to eliminate post-paralytic synkinesis, muscle tightness, and dynamic asymmetry. By permanently reducing excessive resting tone in antagonistic muscles—such as the depressor anguli oris, platysma, or buccinator—this surgery restores natural smile excursion without paralyzing underlying facial expression.
What is Selective Myectomy Surgery?
Following incomplete recovery from facial nerve paralysis (Bell's palsy, Ramsay Hunt syndrome, or acoustic neuroma resection), regenerating nerve fibers frequently trigger aberrant co-contractions. Patients experience severe tightness, involuntary eyelid closure during smiling, or downward pulling of the lip corner. While selective neurectomy modulates the nerve signals driving these contractions, selective myectomy acts directly on the target effector muscle, physically debulking or dividing the hypertonic muscle tissue to establish balance between the paralyzed and healthy sides of the face.
How is Selective Myectomy Performed?
Selective myectomy is performed under general anesthesia or local anesthesia with twilight sedation, typically utilizing hidden intraoral or submental incisions:
- Preoperative Dynamic Vector Mapping: High-resolution clinical video and dynamic palpation isolate the exact muscle slips generating antagonistic vectors (e.g., identifying whether downward pull is driven by the DAO, platysma bands, or both).
- Concealed Incision Access: Depending on the targeted muscle group, access is gained through an intraoral mucosal incision (inside the lower lip/cheek for DAO and buccinator) or a discrete submental crease incision (for cervical platysma bands), preventing visible facial scarring.
- Microsurgical Muscle Isolation: Using surgical loupes or an operative microscope, the surgeon dissects the superficial tissue planes to expose the hyperactive muscle belly while carefully identifying and preserving adjacent motor nerve branches with handheld electrostimulation.
- Targeted Resection (Debulking / Transection): A measured strip of the hyperactive muscle is excised (partial myectomy) or transected to permanently reduce its contractile force. In cases of contralateral lower lip asymmetry, a controlled resection of the non-paralyzed depressor labii inferioris (DLI) may be performed to restore full dental show symmetry during speech and smiling.
- Multi-Layer Mucosal Closure: The intraoral or submental incision is closed using fine, rapidly absorbable sutures, eliminating the need for postoperative suture removal.
Targeted Facial Muscles in Selective Myectomy
Synkinesis presents with distinct muscle-specific movement restrictions. Treatment plans are customized to address specific functional limitations:
- Depressor Anguli Oris (DAO): The primary downward-pulling muscle at the corner of the mouth. Hyperactivity of the DAO suppresses the zygomaticus major, preventing the lip from lifting into a natural smile. Excision of the DAO frees the oral commissure to rise effortlessly.
- Platysma Muscle: Hypertonicity in the platysma causes tight neck bands, chronic cervical stiffness, and lower lip retraction during speech. Platysma myectomy relieves lower face tension and restores smooth contour to the neck.
- Buccinator Muscle: Involuntary spasm of this deep cheek muscle causes internal cheek biting during mastication and creates a persistent feeling of midface tightness. Partial myectomy resolves deep cheek hypertonicity.
- Contralateral Depressor Labii Inferioris (DLI): In chronic facial palsy, the paralyzed lower lip fails to depress during smiling, while the healthy side pulls downward normally. Performing a partial DLI myectomy on the healthy side creates balanced lower teeth exposure and restores smile symmetry.
Selective Myectomy vs. Targeted Muscle Destruction
Choosing between muscle resection, nerve transection, and chemical denervation depends on the chronicity of the synkinesis and previous response to therapy.
| Treatment Modality | Primary Target | Longevity | Primary Clinical Indication |
|---|---|---|---|
| Selective Myectomy | Muscle tissue (resection of hyperactive muscle slips). | Permanent surgical alteration. | Structural muscle tightness, neck bands, DAO smile obstruction, or lower lip asymmetry. |
| Selective Neurectomy | Peripheral nerve branches (selective ablation of aberrant twigs). | Permanent (with minimal recurrence risk under precise mapping). | Widespread multi-focal synkinesis (e.g., involuntary eye closure during smile). |
| Botulinum Toxin (Botox) | Neuromuscular junction (acetylcholine release inhibition). | Temporary (3 to 4 months per treatment). | Early-stage synkinesis, dynamic calibration, or patients seeking non-surgical management. |
Postoperative Recovery and Care Protocol
Because myectomies are frequently performed via intraoral incisions, local hygiene and soft diet adherence are critical during early tissue consolidation:
- Oral Hygiene Management: Rinse with prescribed antiseptic chlorhexidine mouthwash 4–5 times daily after meals for the first 7 days. Avoid aggressive toothbrushing near intraoral suture lines.
- Dietary Modification: Consume soft, non-acidic, room-temperature foods for 7 to 10 days to minimize mechanical stress on the buccal and lower lip incisions.
- Swelling and Ecchymosis Control: Mild lower lip and cheek edema peaks between 48 and 72 hours. Apply cold compresses externally to the jawline and maintain head elevation at 30 degrees during sleep.
- Activity Resumption: Most patients return to desk work and low-impact social activities within 3 to 5 days. High-intensity workouts and contact sports should be postponed for 3 weeks.
Frequently Asked Questions
Is selective myectomy permanent, or can the muscle grow back?
Yes, the results are permanent. Striated facial muscle fibers that have been surgically excised or transected do not regenerate across the resection gap. This provides a long-term alternative for patients seeking freedom from recurring botulinum toxin injections.
Will I have visible scars on my face after myectomy?
No visible facial scars remain. The majority of selective myectomies (including DAO, DLI, and buccinator procedures) are performed entirely inside the mouth through the oral mucosa. When platysma myectomy is performed, incisions are concealed within natural submental (under the chin) skin creases.
Can selective myectomy be combined with other facial reanimation procedures?
Yes. Selective myectomy is routinely combined with modified selective neurectomy, depressor transfers, or static fascial suspensions to address both dynamic nerve misdirection and deep resting muscle tightness in a single operative setting.
How does contralateral DLI myectomy improve smile symmetry?
When the paralyzed side cannot pull the lower lip downward, the healthy lower lip pulls down vigorously, creating severe asymmetry during smiling or showing teeth. By selectively weakening the depressor labii inferioris on the unaffected side, both sides match dynamically, producing a centered, balanced smile.
To learn more about surgical management of facial synkinesis or to evaluate your candidacy for muscle-balancing surgery, schedule a clinical consultation with Dr. Berke Özücer, specialist in facial paralysis treatment.
