Comparative analysis of the histologic alterations caused by microflap technique, microflap with microsuture and microflap with fibrin glue in vocal cord surgery

• Grant number: 09/06918-4
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2009
• End date: January 31, 2012
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Agrício Nubiato Crespo
• Grantee: Agrício Nubiato Crespo
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Benign lesions of the vocal cords are an important cause of dysphonia and represent a significant number of patients attended by the Ear Nose and Throat specialist. In the past decades several techniques have been described for the surgical treatment of these lesions with variable outcome. Satisfactory vocal quality is imperative when considering a good or bad surgical outcome. To achieve satisfactory vocal quality the complex vibratory movement of the vocal cords must be preserved and kept at its best. Scar formation on the vocal cords may compromise vocal outcome and this is the main challenge in microphonosurgery nowadays. Several treatments have been described to solve the problem of scar formation on the vocal cords. Nevertheless satisfactory long-term vocal quality has been describe as quite dissapointing. Studies have focused on the early stages of the scarring process of the vocal cords and on the refinement of surgical techniques as a way to prevent or minimize scar formation. Several authors have searched ways of trying to interrupt the production of substances that may alter the vibratory qualities of the vocal cords during the process of scar formation. There is, on the other hand, a lack of studies comparing diferent surgical techniques and their impact on scar formation. Laryngologists with large series of patients that have been operated by one or other technique have published their results but none have compared different techniques. Clinical reports tend to favor one or other technique but these vary depending on the surgeons personal experience and training, instrumentation and material availability. There is a consensus on the need of maximum preservation of the epithelium and superficial lamina própria and minimal exposure of vocal ligament. On the other hand the need of microsuture or glue to cover the wound is very controversial. The authors propose a comparative study of two variations of the microflap technique one using microsuture and the other using fibrin glue to close the wound. The techniques will be performed on an experimental model to evaluate the effects of each technique on vocal cord healing and scar formation. Healing will be evaluated histologically 10, 30 and 90 days after surgical intervention. A semi-quantitative evalation of the scarring process will be carried out regarding the intensity and extension of inflammatory tissue and the presence of fibrosis. (AU)