Surgery performed by Dr. Xavier Subirana
The complete surgery of intracordal injection of hydroxyapatite made by the Dr. Xavier Subirana, from the Mutua de Terrassa Hospital (Barcelona), can be seen in the online surgical training app SurgSchoolIn this case, we address a left vocal cord paralysis secondary to a mediastinal tumor in a 90-year-old patient, with severe dysphonia and swallowing impairment.
La intracordal injection of hydroxyapatite It constitutes a medialization technique indicated in unilateral paralysis with significant glottic hiatus, especially in frail or elderly patients in whom an effective, low-risk procedure with rapid recovery is prioritized over alternatives such as type I thyroplasty.
Clinical context and indication
The patient presented with a hypophonic voice, high-pitched tone, breathy timbre, and bitonality, with a maximum phonatory time of 1,2 seconds. He also reported an ineffective cough and choking on liquids.
Continuous-wave endoscopy revealed left paralysis with vocal cord atrophy and a glottic hiatus without phonation. Stroboscopy showed a longitudinal hiatus and mucosal flutter (“sail-like”), consistent with severe glottic insufficiency. Videoendoscopy of swallowing revealed mild residue in the vallecula and episodes of penetration with coughing and a wet voice, indicating impaired efficacy and safety.
In this context, the indication of medialization with calcium hydroxyapatite It seeks to improve glottic closure, cough efficiency, and swallowing safety.
Preoperative planning
The preoperative evaluation includes:
- Flexible laryngoscopy and stroboscopy to assess mobility, hiatus, and mucosal wave quality.
- Functional swallowing study.
- Individualized anesthetic assessment given advanced age.
The choice of material is important. Hydroxyapatite offers greater durability than resorbable materials (hyaluronic acid), with less rigidity than other permanent implants, providing stable medialization in patients with a limited life expectancy or in whom frequent reintervention is not anticipated.
Surgical approach
Dr. Subirana performs a suspension microlaryngoscopy under general anesthesia, with flexion-hyperextension positioning to optimize exposure.
Choosing a transoral approach under microscopic vision allows for precision in the depth and location of the injection, minimizing the risk of superficial (subepithelial) or excessively deep injection.
Compared to percutaneous injection in the office, this approach offers greater control in cases with marked atrophy and the need for three-dimensional remodeling.
Key surgical steps
The goal is not simply to "fill," but to rebuild the chordal volume while respecting the surface vibrating layer.
The first puncture is performed in the posterior third, directed towards the medial aspect of the vocal process of the arytenoid cartilage. This step is essential for correcting the posterior hiatus, which is frequently undertreated if only the membranous portion is addressed.
The second puncture is performed more anteriorly, aiming to expand the central vocal cord body. It is crucial to inject at the correct plane, usually into the thyroarytenoid muscle, avoiding the superficial lamina propria to prevent compromising mucosal vibration.
In this case, a third intermediate puncture is added to optimize the medial convexity and homogenize the contour. This intraoperative decision reflects dynamic adaptation based on the observed volumetric response.
Slight overcorrection is acceptable, considering possible tissue readjustment in the first few days.
Critical points and risks
Potential complications include:
- Extensive submucosal hemorrhage.
- Surface injection with vibratory rigidity.
- Excessive injection with respiratory obstruction.
- Migration or extrusion of the material.
Immediate stroboscopic examination reveals hemorrhage of the entire vocal cord and vestibule. This finding is not uncommon and should be interpreted with caution; the relevant factor is the improvement in glottic contact.
Prevention is based on:
- Aspiration before injecting.
- Slow and controlled injection.
- Continuous evaluation of the volume achieved.
Surgical Tips & Pearls
Posterior medialization directed towards the vocal process is crucial in complete paralysis; omitting this point leaves a residual gap.
Multiple strategic punctures are preferable to a single massive injection.
Observing the symmetry of the free edge during injection helps to avoid asymmetric overfilling.
In patients with severe atrophy, the goal is to restore medial convexity, not to create exaggerated protrusion.
Frequent errors
Limiting the injection to the mid-membranous zone without treating the posterior component leads to incomplete closure.
Injecting too superficially produces mucosal rigidity and worsens vocal quality.
Not considering swallowing function as part of the therapeutic goal underestimates the clinical impact of the procedure.
Results and evolution
In the immediate postoperative stroboscopy, more complete glottic contact and initial reappearance of mucosal undulation are already observed, despite the persistence of a high-pitched tone.
Clinically, the improvement in voice quality and cough effectiveness is rapid. In this case, the final voice outcome was optimal, with significant functional improvement in both phonation and swallowing safety.
Follow-up includes endoscopic monitoring and voice evaluation. Hydroxyapatite provides a prolonged effect, reducing the need for reintervention in elderly patients.
For whom is this surgery especially useful?
To ENT residentsThis case illustrates the correct technique of structured medialization by anatomical points.
To young assistantsIt shows the importance of treating the posterior hiatus and adapting the volume intraoperatively.
To experienced surgeons, emphasizes the value of comprehensive functional planning (voice and swallowing) in decision-making.
