Use of regenerative tissue matrix as an oral layer for the closure of recalcitrant anterior palatal fistulae: a pilot study

OBJECTIVES: To evaluate the effectiveness of regenerative tissue matrix (Alloderm) as an oral layer for difficult anterior palatal fistula closure. MATERIALS AND METHODS: The authors have tested the feasibility of a novel surgical technique of adding a regenerative tissue matrix (Alloderm) as an oral layer for closure of recalcitrant large anterior palatal fistulae and report the outcome of the first 12 patients in this pilot study. Patients with recurrent large fistula who otherwise would require either a local pedicled flap, free flap, or an obturator were treated with this technique and followed up for at least 6 months to monitor the progress of healing. RESULTS: Of the 12 patients, 8 patients (66.7%) had complete closure of the fistula, and 2 patients (16.7%) showed reduction in size of the fistula to the extent that symptoms were eliminated, for an overall success rate of 83.3% (10/12 patients). Premature graft loss and recurrence of the fistula were noted in 2 patients (16.7%). CONCLUSION: Alloderm provided an adequate barrier allowing healing to occur unimpeded and allowed closure of the palatal fistula. In our experience, this new technique using regenerative tissue matrix as an adjunct to the oral layer in large anterior palatal fistula has an advantage compared to other more invasive complex procedures and has been shown to provide satisfactory results.

Uso de Matriderm para cobertura cutânea pós-ressecção de úlcera de Marjolin / Use of Matriderm for skin coverage after Marjolin’s ulcer resection

Introdução: Úlcera de Marjolin é um termo comumente referenciado à degeneração maligna de feridas crônicas não cicatrizadas ou cicatrizadas por segunda intenção e a maioria dos casos descritos refere-se a carcinoma espinocelular. A matriz dérmica Matriderm® consiste numa estrutura tridimensional composta de fibras de colágeno bovino e elastina e não existem ainda relatos na literatura do seu uso após ressecções tumorais. O objetivo deste estudo é relatar um caso de úlcera de Marjolin secundária à queimadura de longa data (com 63 anos de evolução), submetido a ressecção e cobertura cutânea com utilização de matriz dérmica de origem bovina (Matriderm®). Relato de Caso: Paciente do sexo masculino, 73 anos, com lesão ulcerada em coxa direita secundária a queimadura por combustão de álcool há 63 anos, com diagnóstico histopatológico de carcinoma espinocelular bem diferenciado, no qual foi realizada ressecção cirúrgica com margens amplas (2 cm) e cobertura do leito cirúrgico com utilização de matriz dérmica bovina (Matriderm®). Conclusão: A utilização da matriz dérmica a celular se mostrou como uma boa opção para cobertura após a ressecção do tumor, com bom resultado estético imediato; porém, ainda tem seu uso limitado, em decorrência do alto custo.

Introduction: Marjolin’s ulcer is a term commonly referred to malignant degeneration of chronic wounds unhealed or healed by secondaryintention and most of the cases described refers to squamous cell carcinoma. The dermal matrix Matriderm® consists of a three-dimensional structure composed of fibers of bovine collagen and elastin, and there are still no reports in the literature of its use after tumor resection. The objective of this study is to report a case of Marjolin’s ulcer secondary to burn of a long time (with 63 years of evolution), who underwentresection and skin coverage with the use of bovine dermal matrix (Matriderm®). Case Report: Patient, male, 73 years, with an ulcerated lesion on the right thigh secondary to burn of alcohol combustion 63 years ago, with histological diagnosis of well-differentiated squamous cell carcinoma, which we performed surgical resection with wide margins (2 cm) and coverage of the surgical site with use of bovinedermal matrix (Matriderm®). Conclusion: The utilization of acellulardermal matrix proved to be a good option for coverage after tumor resection, with good immediate aesthetic result, but still has limiteduse due to high cost.

Comparative study on cell extraction with different reagents in porcine aortic valves / 中华胸心血管外科杂志

Objective To remove cellular compenents from porcine aortic valve with different reagents, providing acellular tissue matrix(ACTM) scaffolds for tissue engineering of heart valve. Methods Different detergents (TritonX-100、Sodium dodecyl sulfate and sodium deoxycholate) and enzyme (trypsin) were used to remove cells and its, compenents from porcine aortic valves, respectively. According to the different detergents, specimens of porcine aortic valve were divided into three groups(Sodium dodecyl sulfate, sodium deoxycholate, and Triton X-100). Specimens were observed grossly uncroscopically. Haematoxylin-eosin and DNA assay was performed to confirm the removal of cells. Transmission electron microscope was used to observe the integrity of collagen and elastin. The changes of mechanical properties were also studied. Results The cells were removed effectively from cusps and roots of porcine aortic valves by Triton X-100 and sodium dodecyl sulfate in 96 h. Sodium deoxycholate could not effectively remove the cells from the root of aortic valve. Treatment with SDS disrupted collagen fiber structure of porcine aortic valve, resulting in poor mechanical properties. Treatment with TritonX-100 result in an acellular porcine aortic valve matrix with retention of near normal structure and mechanical properties. Conclusion Porcine aortic valve can be successfully decellularised with retention of near normal structure and mechanical properties by Triton X-100.