RESUMO
HYPOTHESIS: The use of a material made of bacterial cellulose with the aim of obtaining vocal fold medialization has not hitherto been fully investigated. Although the material has been tested in other animal models, the evaluation did not include the larynx; hence, situations, such as tissue reaction, material absorption, and extrusion, need to be addressed to evaluate its usefulness as a material for laryngeal reconstruction. OBJECTIVE: To evaluate the medialization, tissue response, and healing of rabbit vocal folds, after the implantation of a membrane of bacterial cellulose. STUDY DESIGN: Experimental study. METHODS: A total of 32 rabbits were used, two of which were used to check out the adequacy of the implant location. The animals were followed for 4 months and grouped according to follow-up times of 2, 4, and 16 weeks. All test animals received an implant of bacterial cellulose in one vocal fold and the injection of distilled water in the other, both performed by videoendoscopic cervicotomy. At the end of the follow-up, the presence of inflammatory and medial displacement was evaluated. RESULTS: No statistically significant difference in the inflammatory parameters between the study and control vocal folds or among follow-up times was found. All animals receiving cellulose presented medial displacement of vocal folds, and all retained this material at the implant site up to study endpoint. CONCLUSION: Bacterial cellulose is a useful material for laryngeal medialization, showing no signs of rejection or absorption.
Assuntos
Celulose , Laringe/cirurgia , Implantação de Prótese , Animais , Disfonia/cirurgia , Masculino , Coelhos , CicatrizaçãoRESUMO
UNLABELLED: Based on the functional matrix concept, scientists developed the hypothesis that soft tissue acting on certain bone pieces determines the process of facial growth. The possibility to modify muscle influence in the phase of facial development, or in postoperative of corrective surgery is of great preventive importance and it should be better investigated, since it could reduce the number and impact of these procedures. STUDY DESIGN: experimental in rabbits. AIM: to estimate the relevance of facial muscle activity on facial bones in lab rabbits. MATERIALS AND METHODS: 37 rabbits of two months of age were studied, divided in a study group and a control group, were followed up for a period of 4 months. The study group animals had their facial nerves cut at the cervical root in one side. The facial mesostructure of the animals was removed in block for later morphometric studies through computer graphics made out of the digital pictures of the specimens. Results were submitted for comparative statistical analysis. CONCLUSION: The lack of muscle activity in half of the face produces an ipsilateral shift of the facial mesostructure in developing rabbits.
Assuntos
Ossos Faciais/crescimento & desenvolvimento , Músculos Faciais/fisiologia , Paralisia Facial/cirurgia , Desenvolvimento Maxilofacial/fisiologia , Animais , Face/anatomia & histologia , Paralisia Facial/fisiopatologia , Modelos Animais , Coelhos , Distribuição AleatóriaRESUMO
The granular cell tumor (GCT) is an uncommon neoplasm, with slow progression, usually benign, that can be found in any organ. The most common region for GCT involvement is in the head and neck. Laryngeal involvement is uncommon and accounts for 6 to 10% of all cases reported. Among the major theories of origin and based on the strongest evidence, the most accepted one is that the tumor stems from neuronal tissue. The GCT has a higher incidence in African-descendent patients, and most commonly in their 4th and 6th decades of life. The posterior larynx is the most common laryngeal site. Pediatric laryngeal GCT is rare, anterior subglottis involvement has been described and extensive glottic involvement may occur. Affected patients typically present with hoarseness, dysphagia, cough, haemoptysis, stridor and pain. The GCT presents as a small, firm nodule, sessile or polypoid, with intact mucosa, well outlined but not encapsulated. Cytoplasm granules are typically seen under light microscopy, and the cells are positive for S100 immunoperoxidase and neuron-specific enolase. Treatment of laryngeal GCT is based on surgical excision. This paper describes a pediatric patient with GCT and its clinical course before and after surgical treatment, stressing the importance of GCT diagnosis in the pediatric population. We review clinical course, pathology characteristics and treatment.