Cricothyroid Approximation (CTA)¶
An open-neck voice feminization technique that tilts the thyroid cartilage forward against the cricoid with permanent sutures, lengthening and tensing the vocal folds to raise pitch. Originally described by Isshiki in 1974 as Type IV thyroplasty for vocal fold paralysis with bowing; applied to transfeminine voice raising from the late 1980s.
In 2026 CTA is rarely a primary VFS in centers that also offer Wendler's Glottoplasty. It persists in three niches: as an adjunct to glottoplasty (the Yeson-style protocol — see Feminization Laryngoplasty), as a revision option for inadequate glottoplasty when re-operating intraorally is unattractive, and in centers that haven't adopted endoscopic glottoplasty.
Not the default in 2026
On the data, glottoplasty produces larger and more durable mean F0 gains than CTA in nearly every comparative dataset. CTA is a legitimate technique with a long history, but if you're choosing a primary VFS, the evidence favors glottoplasty unless you have a specific reason (reversibility, failed glottoplasty, surgeon expertise) to choose otherwise.
Mechanics¶
CTA is performed through a transverse cervical incision similar to a tracheal shave. The strap muscles are split to expose the thyroid and cricoid anteriorly. Permanent non-absorbable sutures (2-0 Prolene or Ethibond; stainless steel wire in older descriptions) are passed through the lower border of the thyroid cartilage and the anterior arch of the cricoid, then tied with the larynx tilted into approximation. Typically four sutures in two paramedian columns. The cricothyroid space is intentionally collapsed: the cricoid is drawn upward toward the thyroid, lengthening vocalis and tensing the vocal folds.
The procedure simulates sustained CT muscle contraction. Patients commonly describe a postoperative sensation of the larynx being "pulled down" — that description is anatomically accurate. Phonatorily, mean speaking F0 rises and the entire pitch range shifts upward, but vocal-fold mass and the formant profile are unchanged. Resonance work in speech therapy is still required for a fully feminine percept; see Recovery & Voice Training.
Some surgeons (notably the Yeson group) place a cartilage spacer or screw to prevent sutures from cutting through cartilage, which is the principal late-failure mode. Mastronikolis and others have described titanium mini-plate variants for the same reason.
Operative time, hospital stay, voice rest¶
| Parameter | CTA alone | Combined CTA + glottoplasty |
|---|---|---|
| Operative time | 60–120 min, general anesthesia | ~90–120 min total |
| Hospital stay | 1–2 nights historically; some 23-hour | 1–2 nights typical |
| Absolute voice rest | 3–7 days | 1 week (glottoplasty schedule governs) |
| Speaking voice return | 2–4 weeks | 2–4 weeks |
| Pitch stabilization | 3–6 months | 3–6 months |
Singing voice (if relevant) often does not fully recover for 6–12 months and may not return to pre-op range. Falsetto and head voice are commonly reduced because the CT mechanism is now mechanically pre-engaged.
Pitch gain by series¶
Reported mean F0 increases from the major published series:
| Series | Cohort | Mean F0 gain | Notes |
|---|---|---|---|
| Isshiki et al. 1983 | Early case reports | ~35 Hz | First transfeminine application of Type IV thyroplasty |
| Wendler 1990 / Gross 1999 | German series | 20–40 Hz typical | High inter-patient variance; pre-glottoplasty era |
| Brown, Perry, Cheesman, Pring 2000 | UK, n=14 | ~130 → 184 Hz (~54 Hz) | Short-term; same group documented later regression |
| Neumann & Welham 2004 | Mixed | Mean rise reported | Predictability poor — preop features explained little variance |
| Yeson group (Kim), combined glottoplasty + CTA | Large case series, 2000s+ | 60–90 Hz | Long-term stability claimed; durability credited to glottoplasty component |
A reasonable expectation for CTA alone in 2026 counseling: 20–40 Hz mean F0 gain at one year, with a meaningful subset regressing toward baseline by years 2–3. CTA is not a high-magnitude procedure on average; glottoplasty alone routinely produces larger durable gains.
The regression problem¶
The dominant reason CTA fell out of favor as a stand-alone VFS is loss of pitch over time. The permanent sutures bear continuous tension; over months to years three failure modes accrue:
| Failure mode | What happens |
|---|---|
| Suture cut-out | Suture cheese-wires through cartilage, especially non-calcified younger cartilage. Each millimeter of cut-through partially relaxes the approximation. |
| Suture creep / knot slippage | Even non-absorbable monofilament has measurable creep under sustained load. |
| Cartilage remodeling | The cartilage deforms around fixed hardware, accommodating to a less-approximated resting geometry. |
Documented regression rates:
- Brown et al. 2000 and follow-up reports from the same UK group: a substantial fraction of patients lost most of their initial gain by 2 years.
- Yang, Palmer, Murray, Meltzner, Hillman 2002: long-term F0 measurements showed mean drop of roughly half the initial gain by 2 years in some series.
- The widely-quoted counseling figure — "about 50% of patients lose more than half of their initial gain by 2 years" — comes from synthesis of Brown, Yang, and Neumann/Welham follow-up data and is consistent across groups.
Combined CTA + glottoplasty regresses less. This is the rationale for the Yeson protocol: the glottoplasty component (anterior web formation, which physically shortens the vibrating glottis) heals as scar tissue and is durable, while CTA provides additional acute lift. Even if CTA partially regresses, the glottoplasty floor protects against return to baseline.
CTA as a revision option¶
Patients who underwent Wendler glottoplasty with insufficient pitch rise — or regression as the anterior web stretches or partially dehisces — sometimes pursue CTA as salvage:
- Re-doing intraoral glottoplasty in scarred tissue is technically difficult and carries higher dysphonia risk.
- CTA approaches the larynx externally and works on a different mechanism (length/tension rather than vibrating-segment shortening), so the two are mechanically additive.
- Surgeons who offer CTA-as-revision cluster in European and Korean centers; in North America it is less common because most VFS surgeons specialize in one approach.
The reverse — glottoplasty as revision after failed CTA — is also performed and is arguably more common, given glottoplasty's better long-term durability.
Reversibility — the genuine advantage¶
CTA's one mechanical advantage over Wendler glottoplasty is that it is, in principle, reversible. The sutures can be cut and removed via a second open neck procedure, releasing the approximation and allowing the larynx to return to its native geometry. In practice:
- Reversal is most predictable in the first 6–12 months, before significant cartilage remodeling.
- Late reversal (>2 years) often does not fully restore pre-operative voice — cartilage has remodeled, scar tissue has formed, the CT joint capsule may be permanently altered.
- Wendler glottoplasty creates a healed anterior web of scar tissue; reversal would require re-cutting the web and is rarely attempted because the new vibratory edge does not reliably re-form.
For a patient who places high value on the option of returning to pre-op voice, CTA is the more reversible choice. For a patient who wants the most durable feminization, glottoplasty is the more durable choice. That is the central tradeoff.
CTA vs Wendler glottoplasty¶
| Dimension | CTA | Wendler glottoplasty |
|---|---|---|
| Approach | Open neck, external | Endoscopic, intraoral |
| Mechanism | Tilt cartilages, lengthen/tense folds | Shorten vibrating segment via anterior web |
| Mean F0 gain | 20–40 Hz typical | 40–80 Hz typical |
| Durability | Significant regression in many patients by year 2 | Durable in most patients; web can partially relax |
| Reversibility | Reversible (cut sutures), best within 1 year | Effectively non-reversible |
| External scar | Yes, cervical | No |
| Voice rest | Shorter (3–7 days) | Longer (1–2 weeks strict) |
| Effect on falsetto/range | Often reduces upper range | Often reduces upper range |
| Combined option | CTA + glottoplasty (Yeson) | Standalone or with CTA |
| Primary use in 2026 | Adjunct or revision | First-line in most centers |
Risks and complications¶
Detailed catalog in Risks & Complications. The CTA-specific issues:
| Complication | Notes |
|---|---|
| Suture cut-out / progressive pitch loss | The dominant late complication. Mini-plate or spacer variants address it directly. |
| Suture extrusion or infection | Through skin or into airway; uncommon but reported. |
| Anterior cervical scar | Visible horizontal scar. Patients also pursuing tracheal shave may already accept it. |
| Dysphagia and globus | Altered laryngeal geometry; usually weeks to months, can be permanent. |
| Loss of upper range / falsetto | Pre-tensioned CT mechanism reduces voluntary dynamic range. Singers often regret CTA. |
| Vocal fatigue and strain | Reported in a subset; CT muscle now works against an already-tensioned baseline. |
| Recurrent laryngeal nerve injury | Rare with experienced surgeons; possible given the surgical field. |
| Granuloma formation | At suture sites. |
| Failure to raise pitch | Predictability is the explicit weakness highlighted by Neumann & Welham 2004. |
Singers should be especially cautious
The CT mechanism is the primary lengthening/tensing system used for falsetto and head voice. Pre-engaging it surgically reduces the range a singer can voluntarily produce on top of baseline. Several published series and clinical reports describe singers who regretted CTA for exactly this reason. If singing voice matters to you, weigh that explicitly.
Why CTA is rarely the primary choice in 2026¶
- Glottoplasty produces larger mean F0 gains in nearly every comparative dataset.
- Glottoplasty is more durable, with most patients retaining their gain at 2+ years versus documented regression in CTA.
- No external scar with glottoplasty matters to many patients, especially those not also pursuing tracheal shave.
- Outcome predictability is poor for CTA — Neumann & Welham 2004 is explicit that preop features predict postop F0 weakly.
- The combined Yeson-style protocol captures most of CTA's additive benefit while pairing it with glottoplasty's durability — so even when CTA is used, it is rarely used alone.
CTA remains a legitimate technique with a long published history. For a specific patient — someone who values reversibility, has had a failed glottoplasty, or is operating with a surgeon who specializes in open techniques — it can be the right choice. The default 2026 recommendation for primary VFS is glottoplasty, with or without CTA augmentation, not CTA alone.
Sources¶
- Isshiki N, Morita H, Okamura H, Hiramoto M. Thyroplasty as a new phonosurgical technique. Acta Otolaryngol. 1974;78(5–6):451–457. — original description of the four thyroplasty types, including Type IV / CTA.
- Isshiki N, Taira T, Tanabe M. Surgical alteration of the vocal pitch. J Otolaryngol. 1983;12(5):335–340.
- Brown M, Perry A, Cheesman AD, Pring T. Pitch change in male-to-female transsexuals: has phonosurgery a role to play? Int J Lang Commun Disord. 2000;35(1):129–136. — the UK 14-patient series with documented short-term gain and later regression.
- Yang CY, Palmer AD, Murray KD, Meltzner GS, Hillman RE. Cricothyroid approximation to elevate vocal pitch in male-to-female transsexuals: results of surgery. Ann Otol Rhinol Laryngol. 2002;111(6):477–485.
- Neumann K, Welham NV, Kruse E. Cricothyroid approximation as voice raising surgery: clinical outcomes and prediction of postoperative voice characteristics. J Voice. 2004 — predictability data; preop features explain little variance in postop F0.
- Van Damme S, Cosyns M, Deggouj N, Van Borsel J. The effectiveness of pitch-raising surgery in male-to-female transsexuals: a systematic review. J Voice. 2017;31(2):244.e1–244.e5. — systematic review covering CTA, glottoplasty, and combined procedures.
- Song TE, Jiang N. Transgender phonosurgery: a systematic review and meta-analysis. Otolaryngol Head Neck Surg. 2017;156(5):803–808.