Complications of Various Materials for Injection Laryngoplasty: Systematic Review and Meta-Analysis.

Objective: The purpose of this review is to investigate the complications of various common materials for injection laryngoplasty (IL): autologous fat (AF), calcium hydroxylapatite (CaHA), hyaluronic acid (HA), and carboxymethylcellulose (CMC).

Methods: The literature was queried for articles reporting complications in patients undergoing IL with AF, CaHA, HA, or CMC. Outcome measures include proportions (%) with 95% confidence intervals (CI) of procedural complications (inflammation, granuloma, hematoma, delayed cyst, misplaced/superficial injection, extrusion/migration, and inadvertent overinjection), airway compromise (stridor, dyspnea), and postinjection intervention (steroid treatment, intubation, and tracheotomy). A comparison of proportions, expressed as difference (Δ) and 95% CI, was completed between materials.

Results: Of 551 abstracts identified, 58 studies (N = 2868 patients) were included. Procedural complications following CaHA-IL (11.03% [CI: 4.7-19.5]) occurred at a significantly higher rate than AF-IL (Δ5.97 [CI: 3.1-8.6], P = 0.0001), HA-IL (Δ5.60 [CI: 3.2-8.0], P < 0.0001), and CMC-IL (Δ7.68 [CI: 1.3-10.7], P = 0.024). The highest incidence of airway compromise occurred in HA-IL (3.73% [CI: 1.6-6.6]), followed by AF-IL (1.85% [CI: 0.86-3.5]) and CaHA-IL (0.69% [CI: 0.23-1.6]). Airway compromise was significantly higher following HA-IL compared with CaHA-IL (Δ3.05 [CI: 1.6-4.6], P < 0.0001). There was no significant difference in airway compromise between AF-IL and CaHA-IL (Δ1.17 [CI: -0.07-2.0], P = 0.058) or AF-IL and HA-IL (Δ1.88 [CI: -0.08-3.6], P = 0.055). There was no significant difference in frequency of postinjection intervention in patients undergoing AF-IL (3.53% [CI: 1.8-6.2]) and HA-IL (2.52% [CI: 1.6-3.8]) (Δ1.01 [CI: -1.0-3.9], P = 0.360).

Conclusions: IL is generally safe with the commonly used materials (AF, CaHA, HA, and CMC), with a low overall complication rate across materials. CaHA demonstrates a higher rate of procedural complications, while HA carries a mildly higher risk for airway compromise. Clinicians should select injection material based on patient factors with an awareness for the likelihood of risks based on material.