Homologous Cartilage Grafts

The human immunodeficiency virus (HIV) crisis has all but eliminated the use of cartilage banks, where a surgeon would chemically sterilize with methiolate, alcohol, or other chemicals resected septal cartilage for use in subsequent patients.

Today, most homograft cartilage is irradiated costal cartilage. Cartilage is obtained from donors who meet the criteria required for organ donation. The specimens are tested for VDRL, hepatitis B, HIV, tuberculosis, and slow viruses. The cartilage is then placed in sterile saline and exposed to 30,000-60,000 Gy g-waves to destroy cellular elements and pathogens, including viruses.14 This approach has the advantage of ready availability and does not require an additional surgical harvesting site.

Resorption of homograft cartilage has long been cited as a major drawback to its use. Resorption often depends on the means of preservation of the cartilage. Studies have reported a 42% resorption of methiolate preserved cartilage, whereas irradiated cartilage has provided much greater survival rates.15

Schuller et al.15 reported experience with irradiated homo-graft costal cartilage implants, 22 of which were nasal; 1.4% had partial resorption, and 0% showed warping. These findings were consistent with those reported by Lefkovits,16 in which irradiated homograph costal cartilage was used in 27 patients; 83% had good to excellent results, 14% showed warping, and 0% demonstrated resorption.17

Resorption is related to granulation tissue surrounding the implant, which undergoes transformation into a fibrous capsule that halts further resorption. For this reason, it may be advantageous to avoid the use of systemic steroids in nasal surgery when homograft cartilage grafts are contemplated.

Advantages to the use of homograft cartilage are that no surgical site is required to harvest the grafts, and it does not preclude the use of autogenous cartilage grafts at a later date. The disadvantages of homograft cartilage are a potential immunologic response (i.e., it is not tolerated as well as host tissue), it must be contoured and shaped, and it is susceptible to warping and resorption.

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