A recent study raises the possibility of treating damaged laryngeal cartilage by replacing it with a cartilage scaffold.
The paired arytenoid cartilages of the larynx provide attachment for the vocal folds and together they serve to open and close the airway.
Chondritis or chondropathy is a condition of the arytenoid cartilage, seen especially in young Thoroughbreds. It may result in abscess formation with granulation tissue protruding into the lumen of the airway. Severe cases may result in deformity and dysfunction.
If medical treatment is unsuccessful the affected cartilage can be removed. But this is not without risk of complications such as inhalation of food material and the dynamic collapse of the soft tissue surrounding the larynx during exercise.
The possibility of using a cartilage scaffold to replace the defect was investigated in a study published in the journal Tissue Engineering (Part A).
Dr Marta Cercone and colleagues report the use of an acellular cartilage scaffold, which was produced by treating the cartilage to remove the cells, leaving just the cartilage matrix.
These scaffolds were then implanted into full-thickness defects in both arytenoid cartilages of eight horses. Before implantation, one of the two implants for each horse was seeded with bone marrow-derived nucleated cells (BMNC) collected from each recipient.
The research team found that, two months after the procedure, mucosal epithelium had grown across the surface of the implant and the cartilage had become integrated into the recipient’s arytenoid cartilage. They detected minimal adverse cellular reaction.
They report that pre-seeding the scaffold with BMNC increased the rate at which the scaffold was broken down and incorporated into the recipient cartilage.
They conclude that replacing a portion of the arytenoid cartilage with a tissue-engineered cartilaginous graft pre-seeded with BMNC is surgically feasible in the horse. The procedure is “well tolerated, results in appropriate integration within the native tissue and prevented laryngeal collapse during exercise.”
An exploratory study into the implantation of arytenoid cartilage scaffold in the horse. Marta Cercone, Bryan Brown, Elizabeth C Stahl, Lisa M Mitchell, Lisa Fortier, Hussni O Mohammed, Norm G Ducharme. Tissue Eng Part A (2020). DOI: 10.1089/ten.TEA.2019.0295