Feminization Laryngoplasty (FemLar)¶
Feminization Laryngoplasty (FemLar) is the most extensive of the modern voice feminization surgeries. It is an open procedure performed through a transverse neck incision and combines vocal-fold shortening — the same mechanical principle as Wendler's Glottoplasty — with shortening of the thyroid cartilage frame itself. The technique was developed and popularized at the Yeson Voice Center in Seoul by Hong-shik Choi and Kim Hyung-tae, who together published the canonical operative descriptions and the largest case series.
FemLar produces the largest mean fundamental frequency (F0) gains documented in the VFS literature, at the cost of an external scar, longer recovery, and travel to one of a very small number of centers worldwide that perform it.
For the simpler endoscopic technique see Wendler's Glottoplasty. For the older external pitch-raising procedure see Cricothyroid Approximation. The same incision is routinely shared with Tracheal Shave.
What FemLar adds beyond glottoplasty¶
A standard endoscopic glottoplasty shortens the vibrating length of the vocal folds by suturing the anterior third together after de-epithelialization. The cartilaginous laryngeal frame is left untouched. Mean post-op F0 gain in published series is roughly +30–50 Hz.
FemLar starts from the same mechanical premise but adds two structural moves:
- Anterior commissure advancement (ACA). The anterior commissure — where the two vocal folds meet at the inside of the thyroid notch — is surgically advanced forward, increasing tension on the folds.
- Thyroid cartilage shortening (anterior wedge resection). A vertical midline wedge of cartilage is removed from the thyroid lamina and the cut edges are reapproximated. This narrows the frame side-to-side and shortens the antero-posterior dimension of the larynx.
The combined effect is shorter, tenser vocal folds anchored in a smaller cartilage cage. The result is a higher resonant pitch ceiling than glottoplasty alone can achieve, because the cartilage itself — not just the soft tissue — is reshaped.
The Yeson protocol¶
The Yeson Voice Center protocol, published by Choi and Kim (Journal of Voice, 2017, with follow-up papers), is the reference technique. The operative sequence:
- General anesthesia with a small endotracheal tube routed inferior to the surgical field. Some Yeson cases use a translaryngeal jet ventilation variant.
- Transverse cervical incision, ~4–6 cm, placed in a natural skin crease over the thyroid cartilage. The same incision serves a tracheal shave if combined.
- Subplatysmal flaps raised; strap muscles split in the midline and retracted.
- Exposure of the thyroid cartilage, with careful preservation of the external branch of the superior laryngeal nerve.
- Midline vertical incision through the thyroid cartilage down to but sparing the inner perichondrium.
- The anterior commissure tendon is identified and freed; the anterior thirds of both vocal folds are de-epithelialized through this open exposure (analogous to the Wendler de-epithelialization step but performed externally).
- Anterior thirds of the vocal folds are sutured together to create a surgical anterior commissure web — the vocal-fold-shortening step.
- Anterior wedge of thyroid cartilage resected on either side of the midline, typically a few millimeters per side.
- The anterior commissure is advanced and re-anchored to the new shortened thyroid cartilage edge with non-absorbable sutures, increasing vocal-fold tension as the cartilage closes around it.
- Cartilage edges reapproximated and sutured. Strap muscles, platysma, and skin closed in layers; small drain may be placed.
Thyroid cartilage shortening — the unique element¶
Thyroid cartilage shortening is what most distinguishes FemLar from every other VFS technique. Cricothyroid Approximation tilts the cartilages relative to one another to stretch the folds; glottoplasty shortens only the soft tissue. FemLar physically removes cartilage to make the larynx smaller.
The wedge is taken anteriorly from the thyroid lamina. Width varies with patient anatomy and target pitch but is typically a few millimeters per side. The cut edges are drawn together and fixed, narrowing the thyroid notch angle and reducing the front-to-back length of the vocal folds in concert with the soft-tissue ACA work. This is a second mechanical lever on pitch that glottoplasty alone does not have.
A practical secondary effect: the same cartilage work that shortens the frame also reduces the prominence of the laryngeal cartilage — a partial built-in shave. Most surgeons still perform a formal Tracheal Shave step for full cosmetic correction.
Pitch outcomes¶
FemLar has the highest published pitch-gain numbers in the VFS literature.
| Technique | Typical mean F0 gain | Typical post-op speaking F0 | Notes |
|---|---|---|---|
| FemLar (Yeson series) | +80–110 Hz | 180–220 Hz | Some individuals approach +120–140 Hz; numbers reported at ≥6 months |
| Wendler's Glottoplasty | +30–50 Hz | 150–180 Hz | Endoscopic, no external scar |
| Cricothyroid Approximation | +20–40 Hz | Variable | Frequent regression at 6–12 months |
Single-center evidence base
Yeson is one high-volume center reporting on its own technique. The headline pitch numbers have not been reproduced at the same scale by independent groups. F0 alone is also an incomplete measure of perceived voice gender — resonance, intonation, and vocal weight are not addressed by any VFS, FemLar included. Some pitch settling and partial regression in the first 6–12 months is expected, similar to other VFS procedures.
External incision and scar¶
Unlike endoscopic glottoplasty, FemLar requires an external neck scar. The incision sits in a horizontal cervical skin crease, typically 4–6 cm long, and most patients report it heals well-hidden. Scar maturation follows the usual 12–18-month timeline; silicone sheeting and sun protection are recommended.
For patients prioritizing scarlessness, this is a meaningful tradeoff against the larger pitch gain. The same incision serves a combined tracheal shave — often the deciding factor for patients who want both procedures and don't want two scars.
Combining with tracheal shave¶
Because FemLar exposes the thyroid cartilage from the outside, tracheal shave is naturally combined in the same operative session via the same incision. Most Yeson patients elect this combination.
- One scar instead of two.
- One anesthesia, one recovery period.
- Operative time goes up by ~30–45 minutes for the shave step.
- The shave portion still requires careful intra-op laryngoscopic confirmation of the anterior commissure level so that cartilage above the vocal-fold insertion is preserved. See Tracheal Shave.
A patient considering FemLar plus shave at Yeson should expect both procedures quoted as a single combined operation.
Operative time, anesthesia, hospital stay¶
| Parameter | FemLar alone | FemLar + tracheal shave |
|---|---|---|
| Operative time | 3–5 hours | 3.5–5+ hours |
| Anesthesia | General; small ETT or jet ventilation per surgeon preference | Same |
| Hospital stay (Yeson) | 2–4 days inpatient | 2–4 days inpatient |
| Total time in Korea | ~2 weeks | ~2 weeks |
Yeson's standard package includes inpatient stay plus several days of local hotel-based follow-up before flying home. The two-week window covers surgery, drain removal, suture removal, and the first post-op laryngoscopy.
Recovery¶
For the broader VFS recovery picture and structured voice work see Recovery & Voice Training. FemLar-specific points:
- Strict voice rest: 2–4 weeks. Longer than the 1–2 weeks typical for endoscopic glottoplasty, reflecting both the soft-tissue suture line and cartilage healing.
- Whisper is also restricted. Whispering loads the folds.
- Drain removed at 24–48 h.
- Sutures removed at ~7 days.
- Soft diet for the first week; aggressive throat clearing, coughing, and Valsalva discouraged.
- First voicing at the end of voice rest, gentle phonation under speech-pathology guidance. Yeson provides structured post-op voice therapy as part of the package.
- Pitch trajectory: voice initially sounds breathy and weak; volume and projection return over weeks to months. Final pitch settles at 6–12 months, slightly later than glottoplasty.
- Return to work: desk work feasible at 2–3 weeks with continued voice conservation; jobs requiring heavy voice use (teaching, performance) push out to 2–3 months.
Risks and complications¶
Beyond the standard VFS risks covered in Risks & Complications, FemLar carries open-procedure-specific risks:
- External scar — visible if it heals poorly, hypertrophic, or hyperpigmented.
- Hematoma / seroma under the skin flap.
- Wound infection — uncommon but possible with any open neck procedure.
- Injury to the external branch of the superior laryngeal nerve — weakness of the cricothyroid muscle and loss of upper pitch range; uncommon at experienced centers.
- Cartilage healing failure / nonunion at the wedge resection site — rare; can require revision.
- Suture granuloma / web breakdown at the anterior commissure — same failure mode as glottoplasty; can require revision suture.
- Loss of vocal projection / power — particularly notable for singers; loss of chest-voice and lower range is intrinsic to the technique, not a complication.
- Persistent breathiness or diplophonia — most resolve over months but some persist.
- Pitch over- or under-correction — under-correction is more common than over-correction; revision is possible but technically difficult after open work.
Yeson's published complication rates are low (single-digit percent for most of the above). Independent verification at comparable volumes does not exist.
Geographic concentration¶
FemLar remains heavily concentrated at one center. Yeson Voice Center (Seoul) is by an order of magnitude the largest provider and the originator of the modern technique. A small number of laryngologists outside Korea offer variants of the open thyroid-cartilage-shortening approach, but volumes and published outcomes are far below Yeson's. Patients seriously considering FemLar should expect to travel to Korea.
| Region | Centers offering FemLar or close variants | Notes |
|---|---|---|
| South Korea (Seoul) | Yeson Voice Center | Originator; largest published series; English-language international program |
| United States | A handful of laryngologists | Hybrid open techniques inspired by FemLar; outcomes data sparse |
| Europe | Very limited | Isolated practitioners; case numbers and acoustic data should be requested |
| Surgeon / group | Center | Published technique |
|---|---|---|
| Hong-shik Choi, Kim Hyung-tae | Yeson Voice Center, Seoul | Canonical FemLar protocol — anterior commissure advancement + thyroid cartilage wedge resection |
| Other Yeson laryngologists | Yeson Voice Center, Seoul | Same protocol, high case volume |
| Various | US / EU laryngology programs | Hybrid open feminization laryngoplasty variants; limited published outcomes |
Practical implications of the Korea-centric model
Travel of ~2 weeks minimum. Yeson runs an English-language international patient program with video consultations. Revision and significant complication management is most easily handled by returning to Korea — domestic laryngologists may be unfamiliar with post-FemLar anatomy. A handful of US- and Europe-based laryngologists offer "open feminization laryngoplasty" or hybrid open techniques inspired by FemLar; request specific case numbers and pre/post acoustic data before committing.
For pricing and how to compare programs see Surgeons & Cost.
What to ask in consult¶
| Question | Why it matters |
|---|---|
| What's your FemLar case volume and published outcome data? | Yeson volumes are an order of magnitude above any other center; new programs should disclose theirs. |
| Pre/post acoustic data on your last 20–50 patients? | F0 numbers should be on hand, not anecdotal. |
| Do you combine Tracheal Shave in the same session? | Most Yeson patients do; ask whether the shave is included or quoted separately. |
| What's your specific complication rate for nerve injury and cartilage nonunion? | These are the FemLar-specific bad outcomes; pooled literature is thin. |
| If I need revision, do you do open revisions yourself? | Open-revision expertise is rarer than primary FemLar capability. |
| What does post-op voice therapy look like, and is it included? | Yeson includes structured therapy; not all centers do. |
Sources¶
Canonical Yeson series¶
- Kim HT. Vocal feminization for transgender women: current strategies and patient perspectives. Yeson Voice Center, Seoul. Canonical FemLar technique description and outcome series.
- Choi HS, Kim HT, et al. Yeson group publications on anterior commissure advancement and thyroid cartilage shortening for pitch elevation, Journal of Voice, 2017 and follow-up.
- Yeson Voice Center patient-facing technical descriptions and outcome summaries (yesonvc.com).
Comparative VFS reviews¶
- Song and Cho — comparative review of VFS techniques positioning FemLar against Wendler glottoplasty, CTA, and LAVA.
- Van Damme et al. — VFS outcome review with pitch-gain comparison across techniques.
- Nuyen et al. — VFS technique and outcome review.
Standards¶
- Coleman E et al. WPATH Standards of Care v8 (2022) — voice surgery considerations.