Objectives: To determine the optimum donor site and preparation technique for injecting human autologous cartilage as a potentially permanent implant material for vocal fold medialization.
Study Design: Prospective ex vivo experimental model.
Methods: Human nasal septal and auricular cartilage was obtained from eight surgical cases after institutional review board approval. The auricle and nasal septum were chosen as potential donor sites because of ease of accessibility, volume of cartilage potentially available, and minimal subsequent cosmetic deformity after the tissue harvesting procedure. Various preparation techniques readily available in most operating rooms were tested for their efficacy in generating an injectable cartilage slurry. The various cartilage slurries were injected through sequentially smaller needles and examined cytologically.
Results: The best injection properties for both nasal septal and auricular cartilage were obtained by drilling the cartilage down with a 5 mm otologic cutting bur, which allowed free passage through an 18 gauge needle. Cytologic examination of drilled septal cartilage showed good uniformity of cartilage pieces with a mean largest dimension of 0.44 ± 0.33 mm, and 33% of lacunae contained viable-appearing chondrocytes. Cytologic examination of drilled auricular cartilage was similar, exceptonly 10% of lacunae were occupied by chondrocytes. Other techniques tested (knife, morselizer, and cartilage crusher) did not yield injectable cartilage slurries.
Conclusions: Both nasal septal and auricular cartilage can be prepared for injection via an 18 gauge needle using a cutting otologic bur. Further testing of in vivo viability and long-term volume retention is needed.