Posterior Commissuroplasty

Posterior commissuroplasty, described by others and developed by Dr. Robert Bastian, is an endoscopic procedure designed for individuals who experience airway limitation due to bilateral vocal cord paralysis or bilateral vocal cord fixation. In these conditions, the vocal cords are immobile or fixed in a mostly adducted position, restricting airflow and often causing noisy inspiration (involuntary inspiratory phonation or stridor).

Concept and Rationale

The motivation for this procedure arose from two key observations:

1. Voice preservation was not very good using existing airway-widening techniques.
   • Arytenoidectomy reliably enlarged the airway but produced a very poor voice.
   • Lateral or transverse cordotomy (Kashima) often improved breathing, but voice results were inconsistent and frequently unsatisfactory.
   • Lichtenberger suture lateralization was technically awkward, prone to granulation tissue, and yielded unpredictable voice outcomes.
2. Posterior commissure divots caused by pressure necrosis from intubation might accompany a very good voice. More in detail: among long-term–intubated ICU patients, Dr. Bastian noted several injury patterns:
   
   1. Granulation tissue that resolved spontaneously and “completely”;
   2. Pressure necrosis creating small divots in the medial cartilaginous glottis with preserved arytenoid mobility;
   3. Interarytenoid synechia tethering the arytenoids; and
   4. Cricoarytenoid joint injury limiting motion.

Patients in category b.—those with healed posterior divots and normal joint mobility—retained excellent voice despite a visible posterior “keyhole.”

These observations led to the idea of intentionally creating small posterior commissure divots in the non-vibrating, cartilaginous portion of both cords while preserving joint mobility and membranous vibratory function.

Surgical Technique

Under general anesthesia, the patient is intubated with a small polyethylene tube. After deep anesthesia and hyperoxygenation, the tube is briefly removed. Using a CO₂ laser, the surgeon excises small posterior divots—ideally including a bit of cartilage—from the medial cartilaginous glottis (inhabiting the posterior third of each cord). A depot form of steroid (e.g. triamcinolone) may be injected into the area of the wound to forestall granulation response. The area can also be painted with mitomycin C for the same purpose.

The working principle is: “Start at 1, go to 3, and heal back to 2.”

That is, the created defect is roughly two or three times larger than the anticipated healed opening. The procedure enlarges the posterior glottic airway while sparing the membranous vocal folds and their oscillatory ability.

Perioperative Management

Patients are consented for possible tracheotomy, though this is rarely required. Preoperative steroids are administered to minimize swelling. Because the divots are taken from relatively non-edematous tissue, the risk of airway compromise is low. The narrow airway we entered the O.R. with is considerably larger upon leaving.

Postoperatively, CPAP (not BiPAP) is used for one-hour intervals—and as needed—at the highest tolerable pressure, often 12–15 cm H₂O. Exhalation against resistance acts as a physiologic equivalent of sequential compression devices for the larynx, reducing edema and maintaining airway patency.

Patients are typically observed overnight in a step-down ICU environment and discharged the next morning on a tapering steroid regimen.

Outcomes

In Bastian’s experience, posterior commissuroplasty routinely avoids tracheotomy for patients with bilateral paralysis and achieves the best balance between airway improvement and voice preservation among all current techniques. It is somewhat less effective when dense posterior scarring or fixation is present, yet even then, results are often favorable. The procedure can be repeated if the initial airway gain is less than the patient desired.