Tympanic membrane repair with a dermal allograft.

OBJECTIVES: To assess the use of an acellular dermal allograft in the repair of chronic tympanic membrane perforations. Chronic tympanic membrane perforations are a common problem in otolaryngology, and although surgical tympanoplasty using either temporalis fascia or rice paper has proven to be highly successful, these materials are not without their own limitations. The search has continued for a simpler, yet equally effective, means of repairing persistent tympanic membrane perforations in an office setting. In this study we experimentally evaluated the use of an acellular dermis (AlloDerm, (LifeCell Corporation, The Woodlands, TX) as an alternative to traditional tympanoplasty materials. STUDY DESIGN: Prospective study using 28 adult chinchillas. METHODS: Subtotal tympanic membrane perforations were created bilaterally in 28 adult chinchillas. Animals with noninfected, stable perforations that showed no signs of epithelial regeneration after 5 to 8 weeks were used to compare the use of rice paper patch with AlloDerm in patch tympanoplasties. RESULTS: Eighteen of 23 tympanoplasties (78%) that were performed using AlloDerm showed no signs of perforation after 5 to 6 weeks. In those performed using rice paper control, 14 of 21 (66%) showed no signs of perforation after 5 to 6 weeks. In addition, histological evaluation of the healed tympanic membranes demonstrated that the acellular dermis had been incorporated within the middle fibrous layer of the tympanic membrane. CONCLUSIONS: The results and histological studies suggest that acellular dermis may be a suitable alternative to traditional materials currently used for patch tympanoplasty. Future studies to evaluate the efficacy of acellular dermis in humans are warranted.

Sphenoethmoid cerebrospinal fluid leak repair with hydroxyapatite cement.

Despite advances in neurological, reconstructive, and endoscopic sinus surgery, sphenoethmoid cerebrospinal fluid (CSF) fistulae continually pose difficult management problems. Standard surgical techniques for fistulae closure succeed approximately 78% to 90% of the time. To improve this success rate, hydroxyapatite cement (HAC), a Food and Drug Administration-approved substance for cranial defect repair, was applied to this problem in a clinical setting. Twenty-one patients with spontaneous, posttraumatic, or postoperative CSF leaks of the sphenoid sinus, cribriform plate, or ethmoid region were treated with HAC. Study participants were prospectively accrued at 5 tertiary care medical centers in the eastern United States. The CSF leaks of all 21 patients treated with HAC were successfully sealed by its initial application. The sites of CSF leakage included the nasal cavity (n = 2) and sphenoid sinus (n = 19). Fifteen of the patients had previously undergone a failed repair by standard methods. There have been no recurrent CSF leaks with a maximum follow-up of 72 months, and an average follow-up of 36 months. All patients have survived to date. The only HAC-related morbidity was the extrusion of the HAC when placed in the nasal cavity. Hydroxyapatite cement is an effective method of repair for postoperative, posttraumatic, and spontaneous sphenoid CSF leaks. The efficacy of HAC in sealing the CSF leak was unaffected by previous attempts at leak closure by standard methods or by its origin. Hydroxyapatite cement should not be applied transnasally for the treatment of an ethmoid region fistula owing to its high probability of extrusion. Correct patient selection and technical familiarity with HAC are necessary for successful application.

Acellular dermis for facial soft tissue augmentation: preliminary report.

OBJECTIVE: To evaluate the efficacy of acellular dermis as a viable alternative for soft tissue augmentation in facial reconstruction. DESIGN: A prospective, nonrandomized observational study consisting of 10 patients who underwent soft tissue augmentation with acellular dermis. SETTING: A tertiary care university medical center in an urban setting. PATIENTS: Ten patients who had undergone soft tissue augmentation using acellular dermis participated in this study. Postimplantation follow-up was 17 to 36 months. INTERVENTION: The amount and location for placement of the acellular dermis was left to the discretion of the surgeon. All implants were placed in the subdermal tissues. MAIN OUTCOME MEASURES: The adequacy of acellular dermis for soft tissue augmentation was assessed by subjective evaluation of implant volume persistence, postoperative complications, and the restoration of normal contour. RESULTS: Of 10 patients who underwent implantation, 9 had no complications and 1 had a recurrent sterile abscess or mucocele at the implantation site. A 22-month postimplantation tissue sampling of acellular dermis in a patient with recurrent tumor revealed approximately 80% to 85% volume persistence. CONCLUSION: Preliminary experience with acellular dermis indicates that it shows promise in soft tissue augmentation.